US20150101606A1 - Devices for vaporizing and delivering an aerosol agent - Google Patents

Abstract

A device for vaporizing and delivering an aerosol agent includes a heat generator, a heat conductor in fluid (airflow) communication with the heat generator, and a substrate holder in heat conducting relation with the heat conductor. The heat generator is a handheld, portable torch and the heat conductor defines an annular heat conducting chamber surrounding a substrate disposed within the substrate holder that supports the aerosol agent and an aerosol forming agent. Another device is a handheld, battery-powered heat generator including a heating element in heat conducting relation with a substrate holder. The heating element is a nichrome heating coil wound about the substrate disposed within the substrate holder and electrically coupled to the battery. Another device further includes an auxiliary heat generator having an auxiliary heating element formed by a finely woven wire mesh positioned adjacent the substrate and electrically coupled to the battery.

Description

FIELD OF THE INVENTION
• The present invention relates generally to devices for vaporizing and delivering an aerosol agent. In exemplary embodiments, the invention is a handheld, portable device for vaporizing and delivering an aerosol agent, for example a therapeutic drug in the form of an aerosol to a patient, or nicotine in the form of an aerosol to a smoker.
BACKGROUND OF THE INVENTION
• Therapeutic agents, and in particular drugs, are commonly delivered to a patient, via a pill, capsule, tablet or the like that is ingested orally and absorbed into the bloodstream. A therapeutic agent may also be introduced directly into the bloodstream via an intravenous solution. Therapeutic agents that are ingested orally and absorbed require a longer period of time before the effects of the agent are realized by the patient. Furthermore, agents delivered to a patient via a pill, capsule, tablet or the like suffer from a loss of therapeutic effect due to hepatic metabolism. Intravenous drug delivery, however, is generally inconvenient for a patient that is not resident in a health care facility and can be painful under certain circumstances. Delivery of a therapeutic agent in the form of an aerosol by inhalation overcomes the disadvantages of both delivery methods, but has yet to gain widespread acceptance and use. One possible reason for the limited role of inhalation drug delivery despite its increased efficacy, convenience and painless administration is the lack of a suitable device for portable, reliable, repeatable and simplistic vaporization and delivery of a variety of different drugs in an aerosol form. Existing devices for vaporizing and delivering a therapeutic agent in the form of an aerosol are suitable for use with only a limited class of therapeutic drugs, such as drugs for the treatment of asthma. In addition, none of the existing aerosol agent delivery devices are sufficiently portable, reliable, repeatable and easy to use.
• The adverse health risks associated with smoking cigarettes have been recognized for decades. Accordingly, approximately seventy percent (70%) of smokers today desire to reduce the amount of cigarettes they smoke, or want to quit altogether. Despite the known risks, only an estimated six percent (6%) of smokers are able to quit smoking entirely. The low rate of success is believed to be due to the highly addictive nature of nicotine present in conventional cigarettes. Nicotine gum and nicotine patches for the delivery of nicotine without the harmful by products of combustion have been available for years. Nicotine gum and nicotine patches, however, have proven to be largely unsuccessful smoking cessation devices due to their failure to satisfy the smoker's hand-to-mouth and inhalation urges. In the past few years, nicotine delivery devices in the form of combustion-free electronic cigarettes, commonly referred to as “smokeless cigarettes,” “e-cigarettes” or “e-cigs,” have been developed and introduced to the consuming public.
• Popular brands of e-cigarettes include BLU ECIGS® offered by Lorillard Technologies, Inc. of Greensboro, N.C., VUSE® offered by Reynolds Innovations, Inc. of Winston-Salem, N.C., MARK 1O™ offered by Phillip Morris, Inc. of Richmond, Va., and NJOY® offered by NJOY, Inc. of Scottsdale, Ariz. Each of the aforementioned commercially available e-cigarettes replicate the hand-to-mouth and inhalation experiences of a combustion cigarette desired by smokers. At the same time, they satisfy a smoker's craving for the addictive nicotine without exposing the smoker to the carcinogenic by-products (e.g. tar) produced by the combustion of tobacco, as well as by-standers to second-hand smoke. As a result, e-cigarettes are credited with providing a healthier nicotine delivery option to smokers and a healthy environment to by-standers subjected to second-hand smoke by significantly reducing, and potentially eliminating, the harmful effects of the carcinogens present in the smoke that would otherwise be produced and dispersed by lighting and smoking a traditional combustion cigarette.
• Traditional combustion cigarettes are made of a combustible material that is ignited with a flame to cause tobacco to burn. The burning tobacco releases smoke containing nicotine that is inhaled by the smoker to deliver the nicotine to the lungs. In contrast, e-cigarettes heat a liquid, referred to as “e-liquid,” containing nicotine, and in some instances flavoring, to convert the liquid into a vapor that is inhaled by the smoker to deliver the nicotine to the lungs. E-cigarettes generally include a battery, an atomizer and a hollow, re-fillable cartridge that contains the liquid nicotine. Due to the frequency required to re-fill the cartridge, an advanced type of e-cigarette has been developed that combines the atomizer and the cartridge into a single “cartomizer” connected to the battery. Cartomizers allow for a greater length of time between e-liquid re-fills. The vaporization process is initiated by the smoker inhaling on the cartridge or cartomizer, or alternatively, by the smoker depressing a manual switch that activates the atomizer or cartomizer. The atomizer heats the e-liquid and converts the liquid into a nicotine vapor in the form of an aerosol. The nicotine vapor is inhaled through a mouthpiece provided on the tip of the cartridge or cartomizer to deliver the nicotine to the lungs of the smoker. The smoker then exhales the residual vapor in the form of cigarette smoke without any combustion by-products.
• Despite the reduced health risks, there remain certain disadvantages with the current e-cigarettes. In particular, the e-liquid contained within the cartridge or cartomizer typically contain a solution of propylene glycol, vegetable glycerin (VG), and/or polyethylene glycol 400 (PEG400) mixed with concentrated flavors and a highly variable concentration of nicotine. However, the liquid solutions of certain e-cigarettes still have been found to contain known cancer-causing agents, referred to as tobacco-specific nitrosamines (TSNAs), as well as tobacco-specific impurities, such as anabasine, myosmine, and β-nicotine. In fact, in a recent study the Food and Drug Administration (FDA) detected diethylene glycol, a poisonous and hygroscopic liquid commonly used in anti-freeze solutions, in the e-liquid of one brand of e-cigarette, and measurable levels of nicotine in e-liquid cartridges that claimed to be nicotine-free. These findings are particularly disturbing since the cartridges and cartomizers of e-cigarettes are inherently susceptible to leakage and/or breakage owing to their small size and relative fragility. As a result, the danger exists that a cartridge or cartomizer could leak or break and cause a user to directly inhale a harmful dosage of the liquid solution or a full nicotine delivery without vaporization. It is also possible for a leaking e-liquid to damage the electronics and/or corrode the battery of the electronic nicotine delivery device. Furthermore, the majority of e-cigarettes utilize a rechargeable lithium battery that can potentially explode if the smoking device is mistakenly exposed to the flame from a match, lighter, torch or the like.
• Accordingly, an improved device that is both effective, convenient and easy to use is needed for vaporizing and delivering an aerosol agent, for example a therapeutic drug in the form of an aerosol to a patient, or nicotine in the form of an aerosol to a smoker. Such a device must be capable of vaporizing and delivering a wide range of aerosol agents in a portable, reliable, repeatable and easy to use manner. As used herein, the term “aerosol” is intended to include vapors, gases, fine particles, and the like, both visible and invisible, generated by a heat source acting upon a means for forming an aerosol in a manner consistent with the present invention. As so defined, the term “aerosol” specifically includes any pharmacologically or physiologically active agents, and any desired additives, such as an aerosol forming agent, irrespective of whether they produce a visible aerosol. As used herein, the term “in heat conducting relation” is intended to mean a physical arrangement of two or more components whereby heat is transferred by conduction or convection from a heat generating source (e.g., a heating element) to a thermally conductive component (e.g., a heat conductor or a substrate) substantially throughout the heat generating period of the heat source. A heat conducting relation can be achieved by locating the components in fluid communication, direct physical contact or in close proximity to one another during operation of the heat source.
BRIEF SUMMARY OF THE INVENTION
• To achieve the foregoing and other objects, and in accordance with the purposes of the invention as broadly described herein, the present invention provides devices for vaporizing and delivering an agent in the form of an aerosol, referred to herein as “an aerosol agent.” In the exemplary embodiments shown and described herein, the aerosol agent delivery devices provide a portable, effective, convenient, easy to use device for reliably and repeatedly vaporizing and delivering a wide range of aerosol agents, for example a therapeutic drug in the form of an aerosol to a patient, or nicotine in the form of an aerosol to a smoker.
• In one exemplary embodiment, the invention is a handheld, portable torch for vaporizing an aerosol agent and delivering the aerosol agent to a user. By way of example and not limitation, the handheld torch may be used to vaporize and deliver a therapeutic drug in the form of an aerosol to a patient, or alternatively, nicotine in the form of an aerosol to a smoker. Broadly, the torch includes a heat generator operably coupled with a heat conductor defining a heat conducting chamber, and a generally hollow substrate holder operably coupled with the heat conducting chamber. The heat conductor has a first opening for receiving a heating element of the heat generator and for communicating heat generated by the heat generator to the heat conducting chamber. The heat conductor has a second opening for receiving an end of the substrate holder in heat conducting relation with the heat conducting chamber. The heat conductor has a third opening for allowing ambient air to be drawn through the heat conductor and the substrate holder when a user inhales on an opposite open end of the substrate holder. The heat generator is activated to ignite the heating element and thereby generate heat within the heat conductor that is communicated into the heat conducting chamber. The heat within the heat conducting chamber is conducted to a substrate disposed within the substrate holder that supports at least the aerosol agent and an aerosol forming agent. The conducted heat vaporizes the aerosol agent from the substrate to form an aerosol that is available along with ambient air to be inhaled by the user through the open end of the substrate holder.
• The heating element of the heat generator of utilizes a fuel source consisting essentially of a combustible liquefied gas to generate heat. The combustible liquefied gas preferably is selected from liquefied petroleum gas (LPG or LP-gas), propane, propylene, butylenes, butane, isobutene, methyl propane and n-butane. The substrate may be any heat absorbing material that is non-combustible at the temperature of the heat conducted to the substrate. By way of example and not limitation, the substrate may be formed of a semi-porous cellulose paper material or a finely woven wire mesh material having the aerosol agent and the aerosol forming agent applied to the substrate material. The aerosol forming agent is a polyol preferably selected from glycerin, glycerol, propylene glycol, 1,3-butylene glycol, triethylene glycol, glycryl esters, such as triacetin, propylene carbonate, and mixtures thereof. The aerosol agent may be a therapeutic drug in the form of a heat stable pharmaceutical having less than about 10% alteration and/or degradation under normal transport and storage conditions for treatment of a patient. Alternatively, the aerosol agent may be nicotine for inhalation by a smoker.
• In another exemplary embodiment, the invention is a handheld, portable, battery-powered aerosol agent delivery device for vaporizing an aerosol agent and delivering the aerosol agent to a user. By way of example and not limitation, the aerosol agent delivery device may be used to vaporize and deliver a therapeutic drug in the form of an aerosol to a patient, or alternatively, nicotine in the form of an aerosol to a smoker. Broadly, the aerosol agent delivery device includes a heat generator operably coupled in heat conducting relation with a generally hollow substrate holder. The substrate holder includes an end that is inserted into the heat generator in fluid communication with the ambient air and an opposite open end configured for use by a user to inhale the aerosol agent along with the ambient air. The heat generator includes a heating element disposed about the substrate holder and having an electrical connection with a battery. The heating element generates heat when electrically connected to the battery by a switch. Heat from the heating element is conducted to a substrate disposed within the substrate holder that supports at least the aerosol agent and an aerosol forming agent. The heat vaporizes the aerosol agent from the substrate to form an aerosol that is available to be inhaled by the user along with the ambient air through the open end of the substrate holder.
• If desired, the aerosol agent delivery device may further include an auxiliary heat generator positioned adjacent the substrate disposed within the substrate holder. The auxiliary heat generator includes a generally hollow housing having an open end in fluid communication with the ambient air and an opposite end that is partially closed by an auxiliary heating element. The auxiliary heating element is electrically connected to the battery of the heat generator to produce an electrical current therethrough. Accordingly, the auxiliary heating element generates heat when electrically connected to the battery by the switch of the heat generator. Heat from the auxiliary heating element is conducted to the substrate disposed within the substrate holder adjacent the auxiliary heat generator that supports at least the aerosol agent and the aerosol forming agent. The heat generated by the auxiliary heating element, either alone or in combination with the heat generated by the heating element of the heat generator and likewise conducted to the substrate, vaporizes the aerosol agent from the substrate to form an aerosol that is available to be inhaled by the user along with the ambient air through the open end of the substrate holder.
BRIEF DESCRIPTION OF THE DRAWINGS
• These and other features, aspects and advantages of the invention are better understood and appreciated when considered in light of the following detailed description of the invention with reference to the accompanying drawings.
• FIG. 1 is an environmental perspective view of an exemplary embodiment of a device for vaporizing and delivering an aerosol agent to a user constructed according to the invention illustrating the user utilizing the device to inhale the aerosol agent.
• FIG. 2 is an exploded partial perspective view showing the heat generator, the heat conductor and the substrate holder of the device ofFIG. 1 in a disassembled configuration.
• FIG. 3 is an elevation view showing the heat conductor and the substrate holder of the device ofFIG. 1 in an assembled configuration.
• FIG. 4 is a partial sectional view of the device ofFIG. 1.
• FIG. 5 is a detailed perspective view of the substrate holder of the device ofFIG. 1.
• FIG. 6 is an exploded perspective view showing a coupler and an alternative heat conductor for use with the device ofFIG. 1 in a disassembled configuration.
• FIG. 7 is a perspective view showing the coupler and the alternative heat conductor ofFIG. 6 in an assembled configuration.
• FIG. 8 is a perspective view of another exemplary embodiment of a device for vaporizing and delivering an aerosol agent constructed according to the invention.
• FIG. 9 is a sectional view of the device ofFIG. 8.
• FIG. 10 is a detailed perspective view of the substrate holder and a receiver portion of the heat generator of the device ofFIG. 8.
• FIG. 11 is a detailed perspective view of an auxiliary heat generator for use with the device ofFIG. 8.
• FIG. 12 is a sectional view of the device ofFIG. 6 further including the auxiliary heat generator ofFIG. 11.
• FIG. 13 is a perspective view of a substrate for use with a device constructed according to the invention.
• FIG. 14A illustrates a substrate material for forming a substrate suitable for use with a device constructed according to the invention.
• FIG. 14B illustrates another substrate material for forming a substrate suitable for use with a device constructed according to the invention.
• FIG. 14C illustrates another substrate material for forming a substrate suitable for use with a device constructed according to the invention.
• FIG. 14D illustrates another substrate material for forming a substrate suitable for use with a device constructed according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
• The invention will be described more fully hereinafter with reference to the accompanying drawings in which one or more exemplary embodiments are shown. However, it is to be understood that the invention may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. Exemplary embodiments of the invention are provided herein so that this disclosure will fully and completely convey the broad scope of the invention and to enable one of ordinary skill in the art to make, use and practice the invention without undue experimentation. Like reference numbers in the description and accompanying drawing figures refer to the same or similar elements of the invention.
• The exemplary embodiments provided herein show and describe devices for vaporizing and delivering an agent in the form of an aerosol, also referred to herein as an “aerosol agent,” to a user. As used herein, the term “aerosol” is intended to include vapors, dense gases, fine suspended particles, and the like, both visible and invisible. As so defined, “aerosol” specifically includes any pharmacologically or physiologically active agents, and any desired additives, such as an aerosol forming agent, irrespective of whether they produce a visible aerosol. Ideally, the aerosol has a density consistent with cigarette smoke and a small particle size on the order of about 0.2-3.0 microns. As used herein, the term “aerosol drug” refers to a therapeutic drug in the form of an aerosol available for delivery to a patient for use in inhalation therapy. Similarly, the term “aerosol nicotine” refers to nicotine in the form of an aerosol available for delivery to a smoker for use in smoking a combustion-free electronic cigarette, commonly referred to as a “smokeless cigarette,” “e-cigarette” or “e-cig.” The aerosol agent, and more specifically the aerosol drug or the aerosol nicotine, is preferably formed by an aerosol forming agent activated by heat generated by a heating element and conducted by a heat conductor. An aerosol agent delivery device for vaporizing and delivering an aerosol agent according to the invention provides a portable, effective, convenient, simple to use device for reliably and repeatedly vaporizing and delivering a wide range of aerosol agents to a user. Such devices may be particularly useful for vaporizing and delivering a therapeutic drug in the form of an aerosol drug to a patient, or alternatively, nicotine in the form of aerosol nicotine to a smoker.
• An environmental perspective view of an exemplary embodiment of a device10 for vaporizing and delivering an aerosol agent according to the invention is shown inFIG. 1.FIG. 2 is an exploded perspective view showing the device10 disassembled. The device (also referred to herein as an aerosol agent delivery device)10 comprises aheat generator20, aheat conductor30 and asubstrate holder40.FIG. 3 is an elevation view showing theheat conductor30 and thesubstrate holder40 assembled.FIG. 4 is a partial sectional view of the device10 showing theheat conductor30 and thesubstrate holder40 in greater detail.
• Theheat generator20 may be any means for reliably and repeatedly generating a relatively clean source of heat. As shown and described herein, theheat generator20 is a handheld, portable torch. In a particularly advantageous embodiment, theheat generator20 is a modified form of a commercially available micro butane torch that is capable of generating a localized flame of up to about 2400° F. Examples of a suitable micro butane torch include the BernzOmatic Micro Flame Butane Torch, the Weller ML100 Magna-Lite Butane Torch, and the Blazer PT-4000 Pencil Butane Torch. The specific type, style and brand of theheat generator20, however, are not considered essential to the invention. Regardless, an existingheat generator20 that has proven to be suitable to achieve the primary objectives of the invention is a Weller® Portasol® PSI100 handheld butane heat torch available from Cooper Tools of Apex, N.C. “Weller” is a registered trademark of Cooper Industries, Inc., and “Portasol” is a registered trademark of Oglesby and Butler Ltd.
• As best shown inFIG. 2, theheat generator20 comprises a generallyhollow housing22 configured to contain anignition system23, for example a piezo electronic igniter, aheating element24 and aswitch25 electrically connected to the ignition system for igniting the heating element. If desired, theheat generator20 may also comprise a base, or stand,21 for supporting the aerosol agent delivery device10 in an upright orientation. Theheating element24 comprises a fuel source consisting essentially of a combustible liquefied gas that generates heat when ignited by theigniter23 in response to activation of theswitch25. The combustible liquefied gas preferably is selected from liquefied petroleum gas (LPG or LP-gas), propane, propylene, butylenes, butane, isobutene, methyl propane and n-butane. The combustible liquefied gas comprises hydrocarbons, and in particular, aliphatic hydrocarbons such as carbon alkenes, which are gases at normal atmospheric temperatures and pressures, but are typically compressed to a liquid for storage and transport. Such a combustible liquefied gas is readily available, economical to use and burns cleanly as compared to carbonaceous and fossil fuels. When ignited in the presence of sufficient oxygen, the combustible liquefied gas burns to produce essentially water vapor (H₂O) and carbon dioxide (CO₂). When free oxygen is limited, the ignited combustible liquefied gas also produces small amounts of carbon soot and carbon monoxide (CO). As a result, there is little or no opportunity for the user to inadvertently inhale any harmful or unhealthy by-products or combustion gases produced from ignition of theheating element24.
• As previously mentioned, theheat generator20 may be any suitable device or apparatus for generating heat from a combustible liquefied gas. Preferably, however, theheat generator20 is sufficiently small and lightweight to be held by the user in one or both hands during vaporization and delivery of the aerosol agent. The entire aerosol agent delivery device10, including theheat generator20, theheat conductor30 and thesubstrate holder40 should be small enough and sufficiently lightweight to be portable so that a user can conveniently transport and use the device in any location. Activating (for example, by depressing) theswitch25 causes theigniter23 to ignite theheating element24 and produce a high temperature open flame F (FIG. 4) adjacent a heat discharge end, or tip,26 of theheat generator20. Conversely, deactivating (for example, by releasing) theswitch25 extinguishes the open flame F adjacent thetip26 of theheat generator20. If desired, theheating element24 may be removable from thehousing22 of theheat generator20 for safe storage, as well as for the purpose of replacing an expendable heating element. As shown inFIG. 2, thehousing22 and thetip26 of theheat generator20 define anannular recess28 for receiving theheat conductor30 in a permanent connection, or alternatively, in a temporary relatively tight interference fit attachment, as will be described hereinafter.
• Theheat conductor30 comprises a generallyhollow housing32 configured to be received within therecess28 defined by theheat generator20.Housing32 defines a first opening, or recess,31 at one end adapted for receiving the heat discharge end, or tip,26 of theheat generator20 such that the flame F is disposed within therecess31 of the heat conductor30 (FIG. 4). As shown,recess31 is bounded by anannular lip33 that is configured to removably cooperate with therecess28 defined by thehousing22 and thetip26 of theheat generator20 in a relatively tight interference fit. In this manner,heat generator20 andheat conductor30 are separable for replacement, repair, maintenance and/or cleaning as needed, yet are securely attached so as to remain in physical contact with one another in an airtight connection during use. Regardless,recess31 is in fluid (i.e. airflow) communication with an internal heat conducting chamber34 (FIG. 4) defined by thehousing32 ofheat conductor30. More particularly,housing32 defines a relatively thin, double-walled,annular chamber34 that is in heat communicating relation withrecess31 ofheat conductor30. As a result, heat generated by theheating element24 ofheat generator20 is communicated from therecess31 defined byhousing32 into annularheat conducting chamber34. Combustion gases and excess heat generated byheat generator20 are expelled from the annularheat conducting chamber34 and absorbed into the ambient atmosphere through a plurality of vent holes35 formed through the outer wall of thehousing32 of theheat conductor30 at circumferentially spaced apart locations.
• Housing32 ofheat conductor30 further defines a second opening, or recess,36 (FIG. 2) configured for receiving an end of thesubstrate holder40. It should be noted that in the exemplary embodiments shown and described herein therecess36 does not extend through the entire longitudinal length of thehousing32 ofheat conductor30. Instead,recess36 terminates adjacent, but slightly spaced from, the opposite side of thehousing32 so that thesubstrate holder40 cannot pass through theheat conductor30 if inserted too far intohousing32. As will be readily appreciated by those skilled in the art, it is preferred that the outer surface of thesubstrate holder40 forms a slight interference fit with the inner surface of thehousing32 ofheat conductor30 that definesrecess36. By way of example and not limitation, the diameter ofrecess36 may be tapered in a decreasing manner along the longitudinal length of the recess from the outside ofhousing32 in the direction of the interior of the housing. In this manner, the end of thesubstrate holder40 will remain securely engaged with theheat conductor30 when the substrate holder is inserted into therecess36, as will be described.Heat conductor30 and/orsubstrate holder40 may be made of any substantially rigid material, such as metal, hard plastic, ceramic, glass or the like. In an advantageous embodiment, theheat conductor30 and/or thesubstrate holder40 are formed from Pyrex® glass of the type available from Sigma-Aldrich Company of St. Louis, Mo., or R&H Filter Co., Inc. of Georgetown, Del. “Pyrex” is a registered trademark of Corning, Incorporated of Corning, N.Y.
• As shown,housing32 ofheat conductor30 further defines a third opening, or recess,38 opposite and in fluid (i.e. airflow) communication withrecess36.Recess38 is also in fluid (i.e. airflow) communication with the ambient atmosphere such that ambient air can be drawn viarecess38 into and through thehollow substrate holder40 that is aligned with therecess38 when the end of thesubstrate holder40 is positioned within therecess36. Alternatively,recess38 may be substituted by a plurality of smaller diameter openings each likewise being in fluid (i.e. airflow) communication with the ambient atmosphere and withrecess36 defined byhousing32. Regardless, it is important to note that the overall size (e.g. cross-sectional area and diameter) of therecess38 is smaller than the overall size (e.g. cross-sectional area and diameter) of therecess36 so that the end of thesubstrate holder40 disposed within therecess36 cannot pass through therecess38 formed in thehousing32 of theheat conductor30, as previously mentioned.
• If desired, at least a portion of thehousing32 of theheat conductor30 may be covered by aheat insulator39, such as ceramic, insulating plastic or the like, so as to reduce the temperature generated by theheat generator20 on the exterior surface of the housing. A knownheat insulator39 that can be employed in practicing the invention is a porous, resilient jacket formed from one or more layers of an insulating material. Alternatively, theheat insulator39 could be an expanded metal jacket with or without perforations that is attached to theheat conductor30 and may be spaced from the exterior surface of thehousing32 by an air gap. Preferably, theheat insulator39 extends over substantially the entire outer periphery of thehousing32 of theheat conductor30. Insulating materials which can be used in accordance with the present invention generally comprise inorganic or organic fibers such as those made out of glass, alumina, silica, vitreous materials, mineral wool, carbons, silicon, boron, organic polymers, cellulosics, and the like, including mixtures of these materials. Nonfibrous insulating materials, such as silica aero gel, pearlite, glass, and the like, formed in mats, strips or other shapes can also be used. Preferred insulating materials should have a softening temperature below about 650° C. and should not burn, char or decompose during use. Preferred insulating materials for the heat conductor30 (and similarly thehousing22 of the heat generator20) include ceramic fibers, such as glass fibers available from the Manning Paper Company of Troy, N.Y., under the commercial designations Manniglas 1000 and Manniglas 1200.
• As shown,substrate holder40 comprises an elongate, cylindrical, generally hollowaerosol delivery tube42 having an end configured to be received within therecess36 formed in theheat conductor30. As previously mentioned, the end of thesubstrate holder40 preferably engages therecess36 in an interference fit so that the substrate holder and theheat conductor30 are securely attached to one another during use. Alternatively, the end of thesubstrate holder40 and therecess36 may be provided with a spiral groove and cooperating thread, a light adhesive or any other means suitable for removably securing the end of the substrate holder to thehousing32 of theheat conductor30. As shown herein,substrate holder40 further comprises anannular heat sink44 adjacent and circumferentially disposed about the end of theaerosol delivery tube42 that is inserted into therecess36 of theheat conductor30. Theheat sink44 is made of any solid or semi-porous, non-combustible, thermally conductive material suitable for transferring heat from the annularheat conducting chamber34 into a substrate45 (FIG. 4) disposed within thesubstrate holder40. By way of example and not limitation, theheat sink44 may be a relatively thin, annular ring made of a thermally conductive metal or an impervious silicon or ceramic. Alternatively, theheat sink44 may be a somewhat thicker ring formed from a cellulose material. In other instances, theheat sink44 may be a finely woven wire mesh or perforated metal ring. Typically, however, the selection of the thermal conductivity, porosity, thickness and material of theheat sink44 will be determined by the volatility of the aerosol agent and the aerosol forming agent utilized with the device10.
• Regardless, theheat sink44 is operable to transfer the heat generated by theheat generator20 and communicated to the annularheat conducting chamber34 by theheat conductor30 to thesubstrate45 disposed within thesubstrate holder40. Theheat sink44 is in heat conducting relation with the annularheat conducting chamber34 and with thesubstrate45 to transfer heat from the heat conducting chamber to the substrate by conduction or convection means readily understood and appreciated by those having ordinary skill in the art. In some instances, theheat sink44 is further operable to support thesubstrate45 within thesubstrate holder40. By way of example and not limitation, theheat sink44 is a non-combustible, thermally conductive metal ring that is in direct physical contact with the inner wall of thehousing32 that defines the annularheat conducting chamber34. As a result, heat generated by theheating element24 of theheat generator20 and communicated to the annularheat conducting chamber34 of theheat conductor30 is transferred through the inner wall of thehousing32 into theheat sink44, and subsequently transferred from the heat sink into thesubstrate45.
• As best shown inFIG. 4, thesubstrate holder40 further comprises thesubstrate45 that is disposed within the hollowaerosol delivery tube42 generally concentric with theannular heat sink44. Thesubstrate45 is disposed within theaerosol delivery tube42 in heat conducting relation with theheat sink44. In other words, thesubstrate45 is in direct physical contact with theheat sink44, or is immediately adjacent the heat sink so that heat (i.e., thermal energy) generated by theheating element24 and communicated to the annularheat conducting chamber34 is transferred across the inner wall of thehousing32 to the heat sink and conducted into the substrate. Thesubstrate45 may be made of any suitable thermally stable material having sufficient surface area and/or porosity to contain the aerosol agent and the aerosol forming agent, and furthermore, to permit vaporization aerosol formation by the application of heat. As used herein, “thermally stable” is intended to mean capable of withstanding the high temperatures (e.g., about 200° C. to about 600° C.) generated by theheating element24 of theheat generator20, transferred by theheat conducting chamber34 to theheat sink44 and conducted into thesubstrate45 without causing decomposition or burning of the material of the substrate. Useful thermally stable materials include thermally stable adsorbent carbons, such as porous grade carbons, graphite, activated or non-activated carbons, carbon fibers, carbon yarns, and the like. Other suitable materials include inorganic solids such as ceramics, glass, aluminum pellets, alumina, vermiculite, clays such as bentonite, and the like. In the exemplary embodiments shown and described herein, thesubstrate45 is made from a cellulose-based paper material and/or a metal wire formed as a finely woven wire mesh or screen.
• Thesubstrate45 may have any desired size and shape sufficient to contain at least a single dosage amount of the aerosol agent and enough aerosol forming agent to volatilize (i.e. vaporize) the aerosol agent in the form of an aerosol. In an advantageous embodiment, thesubstrate45 is generally cylindrical and formed from a cellulose-based paper material suitable for low temperature vaporization and aerosol formation at temperatures below the decomposition threshold of cellulose. By way of example and not limitation, thesubstrate45 may be a semi-porous cellulose paper of the type commercially available from EMI Specialty Papers, Inc. of Redding, Conn. The cellulose paper is impregnated with a liquid mixture of the aerosol agent and the aerosol forming agent, or alternatively, the liquid mixture is deposited on the cellulose paper and absorbed. In another advantageous embodiment, thesubstrate45 is made of a metal wire material formed as a finely woven wire mesh comprising one or more layers of wire mesh weaves. An example of such asubstrate45 is a metal filter available from G. BOPP USA, Inc. of Hopewell Junction, N.Y., commercially known as Twilled Dutch Weave Wire Cloth having a 510×3600 warp to weft weave with a warp wire diameter of about 0.025 mm and a weft wire diameter of about 0.015 mm. The preferred BOPP Twilled Dutch Weave Wire Cloth has a nominal filter rating of less than about 1 micron and an absolute filter rating of between about 5 and about 6 microns. The Twilled Dutch Weave Wire Cloth provides extremely small openings to maximize heat conduction and convection, while increasing the surface area available for deposition of the aerosol agent and the aerosol forming agent by as much as 8-fold. The specific weave and warp/weft wire diameter of the metal filter cloth, however, is determined by the optimum delivery characteristics of a particular aerosol agent, and in particular, the boiling point, vaporization rate and aerosol formability of the combination aerosol agent and aerosol forming agent.
• Regardless of the material, the outer periphery ofsubstrate45 is preferably in direct contact with theannular heat sink44 to provide a heat transfer relation between theheat conductor30 and the substrate containing the aerosol agent and the aerosol forming agent. Thus, heat transfer to thesubstrate45 and the resultant production of the aerosol agent for delivery to the user in the form of an aerosol is maximized. Because the aerosol agent and the aerosol forming agent are physically separated from theheating element24 of theheat generator20 by the annularheat conducting chamber34 and theannular heat sink44, the agents are exposed to a lower temperature than the open flame F generated by the heating element within therecess31 of theheat conductor30. Accordingly, the possibility of thermal degradation of the aerosol agent is unlikely.
• FIG. 5 is a perspective view showing thesubstrate holder40 in greater detail. As shown, thesubstrate45 is inserted into the end of thesubstrate holder40 and positioned adjacent and concentric with theheat sink44. The oppositeother end41 of theaerosol delivery tube42 is open to the ambient atmosphere and configured as a relatively small diameter cylinder to engage the mouth of the user (FIG. 1). Alternatively, theopen end41 of theaerosol delivery tube42 may comprise an irregular shaped mouthpiece (not shown) sized to comfortably engage the mouth of the user. Regardless, the length of theaerosol delivery tube42 and optional mouthpiece is selected so that theswitch25 of theheat generator20 is located at a convenient distance from the user, while at the same time theheat generator20 is sufficiently distant from the mouth of the user to limit the ambient temperature. As previously mentioned, thesubstrate45 is made of semi-porous material, for example cellulose paper or finely woven wire mesh, so that the user can draw air from the ambient atmosphere through therecess38 formed inhousing32 ofheat conductor30 and along the longitudinal length of the hollowaerosol delivery tube42. As shown, a relativelysmall diameter hole46 may be formed through the center of thesubstrate45 to increase the amount of ambient air that the user is able to draw through therecess38 and down the longitudinal length of theaerosol delivery tube42, and consequently, significantly reduce the effort required of the user to deliver the aerosol agent to his or her lungs.
• As previously described, the aerosol agent and the aerosol forming agent are deposited onto thesubstrate45 so that the aerosol forming agent can subsequently volatilize the aerosol agent in the form of an inhalable aerosol, or vapor, when heat is applied to the substrate. The aerosol agent and the aerosol forming agent are preferably combined into an admixed solution that is impregnated into or deposited onto thesubstrate45. Regardless, the admixed solution may be applied to thesubstrate45 in any convenient and suitable manner using any conventional means or process. By way of example and not limitation, the admixed solution may be applied to thesubstrate45 by coating, spraying, brushing, dipping, vapor deposition, electrostatic deposition, chemical deposition, or the like such that the admixed solution forms a relatively thin film on the substrate consisting essentially of the aerosol agent and the aerosol forming agent. The aerosol agent may be any thermally stable, non-combustible agent, for example a therapeutic drug or nicotine, capable of being aerosolized and delivered to a user for vapor inhalation. The aerosol forming agent may be any thermally stable, inert aerosol former and/or carrier that is capable of volatilizing the aerosol agent and forming a vapor suitable for delivery to a user of an aerosol agent delivery device according to the present invention. Aerosol forming agents useful in the present invention are capable of forming an aerosol at the temperatures present in theheat conducting chamber34, transferred to theheat sink44 and subsequently transferred into thesubstrate45 when heat is generated by theheating element24. Such agents preferably are composed of carbon, hydrogen and oxygen, but they can include other elements and/or compounds.
• The aerosol forming agent can be in solid, semisolid, or liquid form. Substances having these characteristics include polyhydric alcohols, such as glycerin and propylene glycol, as well as aliphatic esters of mono-, di-, or poly-carboxylic acids, such as methyl stearate, dimethyl dodecandioate, dimethyl tetradecandioate, and others. Preferably, the aerosol forming agent is a polyhydric alcohol, or a mixture of polyhydric alcohols. By way of example, and without limitation, preferred aerosol formers include glycerin, glycerol, propylene glycol, 1,3-butylene glycol, triethylene glycol, glycerol esters, propylene carbonate, and mixtures thereof. As much as possible of the aerosol agent and the aerosol forming agent carried on thesubstrate45 should be delivered to the user. Preferably, above about 50 weight percent, more preferably above about 80 weight percent, and most preferably above about 90 weight percent of the admixed solution is delivered to the user. Thesubstrate45 containing the admixed solution of the aerosol agent and the aerosol forming agent may be provided to the user separately from the device10 as single-dose unit of the aerosol agent, for example a single-dose of a therapeutic aerosol drug to a patient, or alternatively, a single-dose of aerosol nicotine to a smoker. In addition, a plurality ofsubstrates45 may be provided to the user in the commonly used packaging commercially known as a “blister pack” with each substrate vacuum packaged, sealed and individually removable for insertion into thesubstrate holder40 before the substrate holder is inserted into therecess36 of theheat conductor30.
• FIG. 6 is a perspective view showing acoupler30A and analternative heat conductor30B suitable for use with a device10 according to the invention disassembled. Thecoupler30A and thealternative heat conductor30 are advantageous for use when the open flame F generated by theheating element24 ofheat generator20 is subject to extinguishing due to an insufficient amount of oxygen (i.e. air) available within therecess31 of theheat conductor30 to sustain the flame. Thecoupler30A comprises a generallyhollow housing32A having alip33A at one end that defines arecess31A configured to receive thehousing22 of theheat generator20. More specifically,housing32A comprises anannular lip33A at the one end that is sized and shaped to engage the outer surface of thecylindrical housing22 of theheat generator20 in a slight interference fit. Similarly, thealternative heat conductor30B comprises a generallyhollow housing32B having alip33B at one end that defines arecess31B configured to receive the opposite end of thehousing32A of thecoupler30A. More specifically,housing32B comprises anannular lip33B at one end that is sized and shaped to engage the outer surface of thehousing32A of thecoupler30A in a slight interference fit.Coupler30A is provided with slottedopenings37A through thehousing32A andalternative heat conductor30B is provided with like slottedopenings37B through thehousing32B. As shown inFIG. 7,openings37A ofhousing32A andopenings37B ofhousing32B are aligned vertically and overlap to some extent when thecoupler30A and thealternative heat conductor30B are assembled. The slight interference fit between thecoupler30A and thealternative heat conductor30B may be overcome to rotate thehousings32A,32B relative to one another, and thereby vary the extent of the overlap of theopenings37A,37B. The extent of overlap of theopenings37A,37B determines the amount of ambient air available to the open flame F of theheating element24 of theheat generator20. Increasing the extent of the overlap of theopenings37A,37B correspondingly increases the amount of ambient air available to the open flame F disposed within therecess31A of thecoupler30A.
• A perspective view of another exemplary embodiment of adevice50 for vaporizing and delivering an aerosol agent according to the invention is shown inFIG. 8.FIG. 9 is a sectional view of thedevice50, whileFIG. 10 is an enlarged perspective view of a portion of the device. The device (also referred to herein as an aerosol agent delivery device)50 comprises aheat generator60 and a substrate holder, such as thesubstrate holder40 previously shown and described with respect to device10. Theheat generator60 comprises a generallyhollow housing62 configured for containing a conventional battery64 (FIG. 9) and the internal electronics of aswitch65 for activating aheating element68 in heat conducting relation with thesubstrate45 disposed within thesubstrate holder40. As shown herein, a positive terminal of thebattery64 is electrically connected to the electronics of theswitch65 by afirst power wire61, while a negative terminal of thebattery64 is electrically connected to the electronics of theswitch65 by asecond power wire63. Theheating element68 may be any component, structure or material suitable for conducting heat generated by theheat generator60 into thesubstrate45 of thesubstrate holder40. In a particularly advantageous embodiment, theheating element68 comprises a nichrome heating coil made of a length of nichrome wire that is wound around anannular receiver62A depending outwardly from thehousing62 of theheat generator60. The exterior surface of theannular receiver62A may be provided with a spiral groove for assisting to retain the nichrome wire on the receiver. Regardless, one end of thenichrome heating coil68 is electrically connected to the electronics ofswitch65 by afirst heater wire67, while the other end of thenichrome heating coil68 is electrically connected to the electronics of theswitch65 by asecond heater wire69. As will be readily understood and appreciated by those skilled in the art, an electrical current flows through thenichrome heating coil68 whenswitch65 is activated (for example, by depressing the switch) to electrically couple the positive and negative terminals of thebattery64 between theheater wire67 and theheater wire69 of the nichrome heating coil.
• Thereceiver62A may be a structural extension of thehousing62 of theheat generator60. Alternatively, thereceiver62A may be a separate cylindrical component that is permanently secured within a suitably sized and shaped recess formed in thehousing62. Regardless,receiver62A defines an open end configured for receiving an end of thesubstrate holder40 therein. As previously mentioned, one end of theaerosol delivery tube42 of thesubstrate holder40 is removably engaged with the open end of thereceiver62A of theheat generator60. By way of example and not limitation, the end of theaerosol delivery tube42 may engage the open end of thereceiver62A in a slight interference fit. Alternatively, thesubstrate holder40 may be secured to thereceiver62A of theheat generator60 by a tapered press fit, a temporary adhesive, a spiral groove and cooperating thread, or the like. As shown inFIG. 10, the end of theaerosol delivery tube42 may also be provided with alocking tab48 and thereceiver62A of theheat generator60 may be provided with an L-shapedlocking slot49 such that thesubstrate holder40 can be removably locked to thehousing62 of theheat generator60 via thereceiver62A in the well known manner of a bayonet style lock. As previously described, theaerosol delivery tube42 of thesubstrate holder40 is preferably made of a substantially rigid material, such as metal, hard plastic, ceramic, glass or the like, and theopen end41 of the aerosol delivery tube may be provided with a mouthpiece. Furthermore, the end of thesubstrate holder40 that is inserted into thereceiver62A of theheat generator60 may also comprise theheat sink44 for transferring heat produced by thenichrome heating coil68 into thesubstrate45. In yet another embodiment, thenichrome heating coil68 may be replaced by theheat sink44 and the heat sink eliminated from thesubstrate holder40. In still another embodiment, theheating element68 may comprise a relatively thin cylinder formed from the finely woven wire mesh previously described with reference to thesubstrate45 that is attached to the inner or the outer surface of thereceiver62A by, for example, an adhesive. Regardless, theheating element68 transfers heat generated by theheat generator60 into thesubstrate45 disposed within thesubstrate holder40 and having at least an aerosol agent and an aerosol forming agent applied thereto.
• As previously mentioned, and as illustrated inFIG. 10, thesubstrate45 may be formed of cellulose-based paper impregnated with the aerosol agent and the aerosol forming agent. Furthermore, thesubstrate45 may be provided with thelongitudinally extending hole46 for drawing ambient air from the surrounding atmosphere through thehousing62 and/orreceiver62A of theheat generator60, and down theaerosol delivery tube42 of thesubstrate holder40 into the mouth of the user. Alternatively, thesubstrate45 may be formed of the finely woven wire mesh previously described having the aerosol agent and the aerosol forming agent deposited thereon. If desired, a particle filter (not shown) may also be provided, for example within thereceiver62A between thehousing62 and thesubstrate45, and/or between thesubstrate45 and theopen end41 of thesubstrate holder40. Such a particle filter would be useful to filter foreign particulate matter that may be present in the ambient air. Preferably, the particle filter comprises a screen configured to prevent the passage of particulate matter having a mean diameter greater than about 20 microns. In particular, the particle filter is intended to filter any un-vaporized particles of the aerosol agent or the aerosol forming agent and any combustion by-products that may be drawn along with the ambient air into the device10 utilizing the micro butanetorch heat generator20 after being expelled from the annularheat conducting chamber34 into the ambient atmosphere through the vent holes35.
• FIG. 11 is an enlarged perspective view showing anauxiliary heat generator70 for use with thedevice50 described hereinabove.FIG. 12 shows a sectional view of theheat generator60 as previously described further including theauxiliary heat generator70 and operably coupled with an alternative embodiment of anothersubstrate holder80 suitable for use in the present invention. Theauxiliary heat generator70 comprises a generallyhollow housing72 made of a substantially rigid material, such as metal, hard plastic, ceramic, glass or the like.Housing72 defines anannular lip71 at one end configured to be loosely received within thereceiver62A of thehousing62 ofheat generator60 in alignment with a recess,66 formed inhousing62 that is in fluid (i.e. airflow) communication with the ambient atmosphere.Auxiliary heat generator70 comprises anauxiliary heating element74 that is positioned adjacent the opposite other end of thehousing72. As shown,auxiliary heating element74 is formed by a finely woven wire mesh having a firstauxiliary heater wire73 and a secondauxiliary heater wire75 for electrically connecting the woven wire mesh to the electronics of theswitch65 disposed withinhousing62 ofheat generator60 in the manner previously described with respect toheater wire67 andheater wire69 ofnichrome heating coil68. As a result, electric current flows throughauxiliary heating element74 whenswitch65 is activated (for example, by depressing the switch) to electrically couple thebattery64 to theauxiliary heating element70. As shown,hollow housing72 defines a longitudinally extending, axial opening, or recess,76 for a purpose to be described hereinafter.
• Thesubstrate holder80 is inserted into thereceiver62A of thehousing62 ofheat generator60 and secured in a suitable manner previously described. Similar to thesubstrate holder40 discussed hereinabove,substrate holder80 comprises anaerosol delivery tube82 and asubstrate85 containing the aerosol agent and the aerosol forming agent. Theauxiliary heating element74 is located withinreceiver62A adjacent to and in close proximity to thesubstrate85. Thus,substrate85 is simultaneously heated by both theheating element68 of theheat generator60 and theauxiliary heating element74 of theauxiliary heat generator70 when a user activates switch65 (for example by depressing the switch). Heating thesubstrate85, and more particularly, the aerosol agent and the aerosol forming agent applied to thesubstrate85, causes the aerosol agent to be vaporized and made available to theaerosol delivery tube82. As shown herein, thesubstrate holder80 is provided with alongitudinally extending hole86 that is axially aligned with therecess76 formed in thehollow housing72 of theauxiliary heat generator70 and therecess66 formed in thehousing62 of theheat generator60 and in fluid communication with the ambient atmosphere. Accordingly, the aerosol agent is delivered to a user in the form of an aerosol when the user draws ambient air from the surrounding atmosphere through therecess66, therecess76, thesubstrate85, and thehole86 provided in thesubstrate holder80. If desired,substrate85 may be provided with a longitudinally extending through hole that is axially aligned withhole86 ofsubstrate holder80 in the manner previously described with reference tohole46 formed throughsubstrate45 ofsubstrate holder40. As will be readily appreciated, thesubstrate holder80 includingsubstrate85 is intended to be removable from thereceiver62A ofheat generator60 for convenient storage and transport, as well as for the purpose of replacing an expendable substrate. Accordingly,substrate holder80 includingsubstrate85 may be intended for a single use (i.e. disposable), and replaceable with anew substrate holder80 including anew substrate85 having an aerosol agent and an aerosol forming agent applied thereto for each use by a patient or smoker.
• FIG. 13 is a perspective view showing thesubstrate holder80 illustrated inFIG. 12 for use with theauxiliary heat generator70. Thesubstrate85 of thesubstrate holder80 may comprise a shredded cellulose-based material, such as die-cut shredded paper. Alternatively, thesubstrate85 may comprise an expanded starch-based material, such as puffed grain.Substrate85 may also be formed of a combination of a cellulose-based material and an expanded starch-based material in a manner well known to those skilled in the art of conventional cigarette manufacture. As shown, theaerosol delivery tube82 of thesubstrate holder80 may further comprise afiller portion84 adjacent thesubstrate85 and anoptional filter portion88 adjacent the opposite end of the substrate holder, such that thefiller portion84 is medially disposed between thesubstrate85 and thefilter portion88. Furthermore, the lengthwise, longitudinally extendinghole86 may also be formed through thefiller portion84 and through thefilter portion88.Hole86 functions to increase the amount of ambient air that the user is able to draw through therecess66 formed inhousing62 ofheat generator60, therecess76 of theauxiliary heat generator70,substrate85 andaerosol delivery tube82, and thereby significantly reduce the amount of effort required to deliver the aerosol agent to the user's lungs in the manner previously described with reference tohole46 formed throughsubstrate45 ofsubstrate holder40. If desired,hole86 may likewise extend throughsubstrate85 in the same manner that hole46 extends throughsubstrate45.Filler portion84 may be made of a version of the shredded cellulose-based material and/or expanded starch-based material of thesubstrate85 having a significantly reduced density. Conversely,filter portion88 may be made of a similar material as thesubstrate85 having a somewhat greater density. Theaerosol delivery tube82 containingsubstrate85,filler portion84 andfilter portion88 may be formed from a cellulose-based material, such as thin film paper, in the same manner as the wrapping of a conventional cigarette. In addition, thesubstrate holder80 may further include aheat sink44 made of a thermally conductive material, such as a cylindrical metal band or a finely woven wire mesh screen in the form of a hollow cylinder, disposed concentrically about thesubstrate85, as previously described with reference tosubstrate holder40.
• FIGS. 14A-14D illustrate examples of materials that may be utilized to form thesubstrate45 ofsubstrate holder40 or thesubstrate85 ofsubstrate holder80 shown and described herein.FIG. 14A illustrates strips or shreds of an expanded starch-based material and/or cellulose-based material that forms the substrate.FIG. 14B illustrates nuggets, chips or shards of an expanded starch-based material and/or cellulose based material that forms the substrate.FIG. 14C illustrates a relatively thin sheet, layer or film of an expanded starch-based material and/or cellulose-based material that is formed into a generally hollow, cylindrical substrate. Likewise,FIG. 14D illustrates a relatively thin sheet, layer or film of a finely woven wire mesh material that is formed into a generally hollow, cylindrical substrate. In each instance, the aerosol agent and the aerosol forming agent are applied to the material of the substrate in a suitable manner that facilitates vaporization of the aerosol agent from the substrate of the substrate holder. As previously mentioned hereinabove, the finely woven wire mesh material may also, or alternatively, be utilized to form the thermallyconductive heat sink44 of thesubstrate holder40, theheating element68 of theheat generator60, and/or theauxiliary heating element74 of theauxiliary heat generator70.
• The aerosolagent delivery devices10,50 of the present invention are each designed to deliver a wide range of aerosol agents to a user, for example a therapeutic drug in the form of an aerosol to a patient for inhalation therapy, or nicotine in the form or an aerosol to a smoker. Regardless, the aerosol agent is provided to the user in an effective, yet convenient, portable and simple to use device for repeatedly and reliably vaporizing and delivering the aerosol agent. The aerosol agent delivered to the user consists essentially of air, the aerosol agent (e.g. therapeutic drug, nicotine, etc.) and the aerosol forming agent. The aerosol agent may also contain any desired flavorant or inert additive for improving the taste, consistency or texture of the aerosol agent, thereby making the inhalation therapy more palatable to a patient or to a smoker. The aerosol agent should have no significant mutagenic activity as measured by the industry standard Ames test. An aerosol agent delivery device10 according to the present invention, when used properly, should deliver very low levels of carbon monoxide, preferably less than about 1 mg total CO delivery over the life of the device, more preferably less than about 0.5 mg total CO delivery, and most preferably essentially no total CO delivery.
• The foregoing is a description of various embodiments of the invention that are given here by way of example only. Although aerosol agent delivery devices for vaporizing and delivering an aerosol agent to a user have been described herein with reference to the accompany drawing figures in which exemplary embodiments are shown, other embodiments of the invention may exist or become later known that perform similar functions and/or achieve similar results. All such equivalents are within the spirit and scope of the present invention, and thus, are intended to fall within the broadest reasonable interpretation of the appended claims consistent with this specification.

Claims (24)

1. A device for vaporizing and delivering an aerosol agent to a user, the device comprising:

a heat generator operable for generating heat;

a heat conductor configured to be in heat conducting relation with the heat generator, the heat conductor having an annular portion operable for conducting heat generated by the heat generator;

a substrate holder configured to be received by the heat conductor in heat conducting relation with the annular portion of the heat conductor;

a substrate disposed within the substrate holder and positioned concentrically relative to the annular portion of the heat conductor with the substrate holder received by the heat conductor, the substrate supporting an aerosol agent and an aerosol forming agent thereon, the aerosol forming agent operable for vaporizing the aerosol agent in response to heat generated by the heat generator and conducted to the substrate via the annular portion of the heat conductor, and the substrate holder operable for delivering the aerosol agent to the user in the form of an aerosol through the substrate holder.

2. The device according toclaim 1, wherein the annular portion of the heat conductor defines an annular heat conducting chamber.

3. The device according toclaim 1, wherein the heat generator is a handheld, portable torch comprising a heating element activated by a switch that utilizes a fuel source consisting essentially of a combustible liquefied gas.

4. The device according toclaim 3, wherein the combustible liquefied gas is selected from the group comprising liquefied petroleum gas (LPG or LP-gas), propane, propylene, butylenes, butane, isobutene, methyl propane and n-butane.

5. The device according toclaim 3, wherein the combustible liquefied gas is ignited by a piezo electronic igniter.

6. The device according toclaim 2, wherein the annular heat conducting chamber of the heat conductor is defined by a relatively thin, double-walled housing.

7. The device according toclaim 6, wherein the housing is made of a substantially rigid material selected from the group consisting of metal, hard plastic, glass, ceramic and the like.

8. The device according toclaim 7, wherein the heat conductor defines a first recess for receiving the heat generator therein, a second recess for receiving an end of the substrate holder therein, and a third recess in fluid communication with the second recess and with the ambient atmosphere.

9. The device according toclaim 1, wherein the substrate is made of a semi-porous material selected from the group consisting of cellulose-based material and expanded starch-based material adsorbed with an admixed solution of the aerosol agent and the aerosol forming agent.

10. The device according toclaim 1, wherein the substrate comprises a finely woven wire mesh having the aerosol agent and the aerosol forming agent deposited thereon.

11. The device according toclaim 1, wherein the aerosol forming agent is a polyol selected from the group consisting of glycerin, glycerol, propylene glycol, 1,3-butylene glycol, triethylene glycol, glycerol esters, propylene carbonate, and mixtures thereof.

12. The device according toclaim 1, wherein the heat generator comprises a battery and a heating element electrically coupled to the battery, the heating element comprising a nichrome heating coil formed by an elongate length of a nichrome wire wound about the annular portion of the heat conductor, the substrate being positioned concentrically relative to the nichrome heating coil.

13. The device according toclaim 12, wherein the heating element is activated by a switch electrically connected between the battery at least one end of the elongate length of the nichrome wire.

14. The device according toclaim 13, further comprising an auxiliary heat generator comprising an auxiliary heating element positioned adjacent the substrate disposed within the substrate holder and electrically connected to the battery through the switch.

15. The device according toclaim 14, wherein the auxiliary heating element is formed by a finely woven wire mesh.

16. The device according toclaim 1, wherein the substrate is made of at least one of a shredded cellulose-based material and an expanded starch-based material.

17. The device according toclaim 1, wherein the substrate holder comprises an elongate, cylindrical, generally hollow aerosol delivery tube and an annular heat sink made of a thermally conductive material that is disposed between the heat conductor and the substrate and positioned concentrically relative to the annular portion of the heat conductor.

18. The device according toclaim 1, wherein the substrate holder comprises an elongate, cylindrical, generally hollow aerosol delivery tube configured for containing the substrate at one end thereof, a filter portion at an opposite end thereof, and a filler portion disposed medially between the substrate and the filter portion, each of the aerosol delivery tube, substrate, filter portion and filler portion being made of a cellulose-based material.

19. An aerosol agent delivery device comprising:

a heat generator comprising a heating element operable for generating heat utilizing a fuel source consisting essentially of a combustible liquefied gas;

a heat conductor in fluid communication with the heating element of the heat generator, the heat conductor having an annular portion defining an annular heat conducting chamber operable for conducting heat generated by the heating element;

an elongate, cylindrical, generally hollow substrate holder configured to be received by the annular portion of the heat conductor and in heat conducting relation with the heating element of the heat generator via the annular portion of the heat conductor; and

a substrate disposed within the substrate holder, the substrate holder being received by the heat conductor such that the substrate is positioned concentrically relative to the annular portion of the heat conductor, the substrate supporting an aerosol agent and an aerosol forming agent thereon, the aerosol forming agent being adapted for vaporizing the aerosol agent in response to heat generated by the heating element of the heat generator and conducted to the substrate via the annular portion of the heat conductor, and the substrate holder being adapted for delivering the aerosol agent to the user in the form of an aerosol when the aerosol forming agent vaporizes the aerosol agent supported on the substrate in response to the heat generated by the heating element of the heat generator and conducted to the substrate through the annular portion of the heat conductor.

20. An aerosol agent delivery device comprising:

a heat generator operable for generating heat, the heat generator comprising a battery, a heating element and a switch for electrically connecting the heating element to the battery;

a heat conductor in heat conducting relation with the heat generator, the heat conductor having an annular receiver operable for conducting the heat generated by the heating element of the heat generator;

an elongate, cylindrical, generally hollow substrate holder heat configured to be received by the annular receiver of the heat conductor in heat conducting relation with the heating element of the heat generator; and

a substrate disposed within the substrate holder and positioned concentrically relative to the annular receiver of the heat conductor, the substrate supporting an aerosol agent and an aerosol forming agent thereon, the aerosol forming agent being adapted for vaporizing the aerosol agent in response to the heat generated by the heating element of the heat generator and conducted to the substrate via the annular receiver of the heat conductor, and the substrate holder being adapted for delivering the aerosol agent to the user in the form of an aerosol when the heating element of the heat generator heats the substrate through the annular receiver of the heat conductor and the substrate holder.

21. The device according toclaim 1, wherein the substrate holder comprises an elongate, annular aerosol delivery tube and wherein the substrate defines a central opening for drawing ambient air through the substrate and the aerosol delivery tube.

22. The device according toclaim 19, wherein the substrate holder comprises an elongate, annular aerosol delivery tube and wherein the substrate defines a central opening for drawing ambient air through the substrate and the aerosol delivery tube.

23. The device according toclaim 20, wherein the substrate holder comprises an elongate, annular aerosol delivery tube and wherein the substrate defines a central opening for drawing ambient air through the substrate and the aerosol delivery tube.

24. An aerosol agent delivery device, comprising:

a heat generator operable for generating heat and in heat conducting relation with an annular portion of a heat conductor; and

a substrate holder in heat conducting relation with the annular portion of the heat conductor, the substrate holder comprising:

an annular aerosol delivery tube defining a longitudinally extending first central opening; and

an annular substrate disposed within the substrate holder and positioned concentrically relative to the annular portion of the heat conductor, the substrate being formed of a semi-porous material selected from the group consisting of a cellulose-based material, an expanded starch-based material, and a finely woven wire mesh material comprising an aerosol agent, the substrate defining a longitudinally extending second central opening in fluid communication with the first central opening of the aerosol delivery tube and with a source of ambient air to permit a user to draw the ambient air through the substrate and the aerosol delivery tube and thereby deliver the aerosol agent when the heat generated by the heat generator is conducted to the substrate via the annular portion of the heat conductor and the aerosol agent is vaporized.

Images