US20070102013A1 - Electrical smoking system - Google Patents

Abstract

A tobacco mass is heated to a temperature of about 150° to about 220° C. to release flavorful tobacco volatiles, which are entrained in air passing through the tobacco mass, and condensed to form an inhalable aerosol. The tobacco mass may have a rotationally symmetric shape, with at least part of its surface in heat transfer relationship with a heater. The heater may be an external shell, an internal rod, or a plate. A shell can enclose the heater and tobacco mass and define a preheating chamber for inflowing air. A mouthpiece, with or without a filter, may be arranged in fluid communication with the tobacco mass to direct the aerosol from the heating system.

Description

FIELD OF THE DISCLOSURE
• This disclosure relates generally to tobacco smoking systems using electrical energy rather than combustion. More particularly, the smoking system disclosed here generates an aerosol through conductive and/or convective combustionless heating of tobacco by an electrical heating source.
SUMMARY
• A quantity of tobacco is placed in contact with a heating system. Passageways are provided for air to move through the heating system and the tobacco. The heating system raises the temperature of the tobacco to the range of about 150 to about 220° C. by direct contact with the tobacco, by convective heat transfer to the tobacco, and/or by heating the air which in turn heats the tobacco. The heated tobacco releases volatiles which subsequently cool to form an aerosol for delivery from the heating system.
• The tobacco may have a variety of shapes including without limitation a pillow shape, a generally rotationally symmetric shape, a generally cylindrical plug, a generally cylindrical shell, a generally circular disk, a plug shape, a pellet shape, a cigarette shape, and the like.
• The heating system may also have a variety of configurations. By way of example, and without limitation, the heating system may include a heating element such as a generally cylindrical heated shell with both ends open, a generally cylindrical heated shell with a closed end, an insertable heating element, a heated disk, a pair of heated disks, or the like. Such heating elements may be fabricated from an electrically resistive material which heats when electrical current passes through it. Such heating elements may also include either internal or external heating devices such as wires. Air may pass axially through the tobacco and the heating system. Alternatively, air may enter the tobacco radially and exit substantially axially. In addition, the heating system may be arranged such that air is preliminarily heated before being directed into the tobacco.
• If desired, a mouthpiece, with or without a filter, may be used with the heating system both to define a cooling region for the tobacco volatiles, and to direct the resulting aerosol to the consumer.
BRIEF DESCRIPTION OF THE DRAWINGS
• The accompanying drawings depict several embodiments of the electrically heated tobacco smoking system of this disclosure. In the accompanying drawings, like reference numerals are applied to like elements.
• FIG. 1 is a cross-sectional view of an electrically heated tobacco smoking system.
• FIG. 2 is a cross-sectional view of the electrically heated tobacco smoking system taken along the line2-2 ofFIG. 1.
• FIG. 3 is a cross-sectional view of another embodiment of the electrically heated tobacco smoking system.
• FIG. 4 is a cross-sectional view taken along the line4-4 ofFIG. 3.
• FIG. 5 is a cross-sectional view of the electrically heated smoking system ofFIG. 1 including a mouthpiece.
• FIG. 6 is an end view of the electrically heated tobacco smoking system ofFIG. 5.
• FIG. 7 is a cross-sectional view of a third embodiment of the electrically heated tobacco smoking system.
• FIG. 8 is an end view of the electrically heated tobacco smoking system ofFIG. 7.
• FIG. 9 is a cross-sectional view of an electrically heated tobacco smoking system using a pillow of tobacco material.
• FIG. 10 is an end view of the electrically heated tobacco smoking system ofFIG. 9.
• FIG. 11 is a cross-sectional view of an electrically heated tobacco smoking system having radial inflow of air.
• FIG. 12 is an end view of the electrically heated tobacco smoking system ofFIG. 11.
• FIG. 13 is a cross-sectional view of an electrically heated tobacco smoking system having counter-current heat exchange.
• FIG. 14 is an end view of the electrically heated tobacco smoking system ofFIG. 13.
• FIG. 15 is a cross-sectional view of an electrically heated tobacco smoking system with a toroidal tobacco mass.
• FIG. 16 is a cross-sectional view taken along line16-16 ofFIG. 15.
DETAILED DESCRIPTION
• Turning toFIG. 1, an electrically operatedtobacco smoking system20 according to this disclosure is depicted. Thesmoking system20 includes at least aheating system22 and a tobacco mass that may comprise aplug24 of cut filler tobacco. The heating system may be an inductively heated arrangement, a resistively heated arrangement, a radiantly heated arrangement, or a convectively heated arrangement. Here, resistively heated arrangements will be described as currently preferred embodiments. Thetobacco plug24 preferably weighs in the range of 5 to 500 mg. For single and multiple puff applications, weights in the range of 5 to 150 mg. are more preferable. Weights in the range of 300 to 500 mg. are more preferable where tobacco is to be used on multiple occasions. The tobacco mass may be made from any type of tobacco, or from any portion of the tobacco plant including, without limitation, sheet products, dust, leaf, stem, and combinations thereof. In the final form, the tobacco mass could involve any type of common tobacco processing steps including, without limitation, blending, flavoring, and the like.
• If desired, thetobacco plug24 may include a paper or mesh cover or carrier to facilitate handling. When paper is used around the tobacco plug, the paper substrate may have porosity and weight selected according to the particular shape of the heating chamber and the manner in which thetobacco plug24 is to be used. For example, where thetobacco plug24 is replaceable, the paper needs to have sufficient strength to maintain integrity of the tobacco plug during handling, removal, and insertion. Moreover, where the paper covers the principal movement of air through the smoking system, the paper needs to have sufficient porosity to allow air movement therethrough. Where a mesh material is selected, mesh opening should be sized small enough to contain a substantial majority, if not all, of the cut filler tobacco particles.
• The tobacco mass may also be formed from tobacco particles. Whether particles or other tobacco cuts are used, the tobacco itself may function as a binder to hold tobacco pieces in a preferred shape. If desired, the tobacco used in the system can be pretreated to enhance flavor generation. Similarly, if desired, flavorants can be provided on the tobacco surface.
• The tobacco mass may be rotationally symmetric in shape or configuration. Moreover, the tobacco mass may be generally cylindrical, disk-like, or generally toroidal. Where a cylindrical configuration is adopted, it may be solid or shell-like with an open center. The particular shape of the tobacco mass is preferably adapted to the shape of the heating apparatus.
• Theheating system22 substantially encloses or surrounds a substantial portion of the tobacco mass such that at least part of the surface of the tobacco mass conforms to the heating apparatus. An actuation system connected with theheating system22 is operable to electrically energize theheating system22. The actuation system may include a source of electrical energy such as one ormore batteries37. To preserve battery life and to control activation of theheating system22, asuitable switch38 may be connected in series with thebatteries37. Depending on the application, theswitch38 may be a push-button switch, a flow sensing device, or a puff sensing device. Asuitable conductor36 connects thebatteries37, theswitch38, and theheating system22 in series.
• Theheating system22 is operable to heat the tobacco mass to a temperature in the range of about 150° to about 220° C. to release flavorful volatiles without reaching the tobacco kindling temperature and without generating smoke and/or ash. Further, the heating system defines a heat transfer channel or pathway through which air is directed.
• As shown, theheating system22 may comprise a generally cylindrical shell having both ends open. As best seen inFIG. 2, the generally cylindrical shell surrounds the sides of thetobacco plug24. Theheating system22 is electrically energized to generate heat. To that end, theheating system22 may be connected to a suitable source of electrical energy, such as, for example, domestic power grid, portable power generating devices like an automobile cigarette lighter, batteries, and any other suitable conventional source. The source of energy must be capable of delivering heat from theheating system22 to thetobacco plug24 so that the tobacco in the plug is raised to a temperature in the range of about 150° C. to about 220° C. Within this temperature range, the tobacco releases flavorful volatiles that produce a satisfying experience while generating little to no visible smoke.
• Theheating system22 may operate continuously for a period of time corresponding to the length of time normally used to smoke a cigarette. Conventionally, that length of time is typically taken as about 5 to 10 minutes. Alternatively, theheating system22 may operate intermittently, on demand, for example in response to puffs by the system user.
• In use, theheating system22 is activated, for example, by a puff sensor or a suitable “on-off” device.Ambient air26 is drawn through theopen end28 of theheating system20 and into thetobacco plug24. Theheating system22 closely conforms to the periphery of thetobacco plug24 and heats thetobacco plug24 to the desired temperature range (about 150° C. to about 220° C.) by conductive and/or convective heat transfer to release flavorful volatiles from the tobacco. As theambient air26 moves through thetobacco plug24, theair26 entrains the released tobacco volatiles and distills those volatiles by cooling them. As the air with entrained volatiles leaves the second end of theheating system22, seearrow30, exposure to ambient air further cools the entrained volatiles to form anaerosol32 which is delivered from theheating system22.
• If desired, an aerosol former may be added to thetobacco plug24. Suitable aerosol formers include, for example, glycerol, propylene glycol, triacetin, and the like, as well as mixtures thereof. Concentrations of aerosol former in the range of about 0 to about 25% by weight can be used. The aerosol formers also enhance tobacco involvement in the aerosol formation.
• After thetobacco plug24 has been used, it may be removed from theheating system22 and replaced with a fresh plug or cartridge. The spenttobacco plug24 may be discarded.
• It will be appreciated by those skilled in the art that the electric tobacco smoking system described herein provides numerous advantages. For example, a smaller amount of tobacco is used so tobacco supplies can be extended. By using less tobacco, the disposable waste from the smoking experience is also reduced. In addition, since the heating system releases principally the flavorful volatiles from the tobacco which may be perceived as more pleasing than the sidestream aroma resulting from cigarette combustion.
• Thetobacco plug24 is not subject to actual combustion as occurs with lit-end smoking articles. Because the electric tobacco smoking system described here does not have a smoldering coal, it presents less risk of starting a fire when carelessly handled than a conventional lit-end cigarette. For the same reason, the smoking system herein described requires less cleaning as there is essentially no ash with which to contend. Furthermore, the disposable waste which does exist has less residual aroma due to the lack of combustion. Moreover, absence of smoke should obviate non-smoker objections to second-hand smoke.
• Of course, various other embodiments of the electric tobacco smoking system are not only possible but also are within the scope of this disclosure. For example (seeFIG. 3), thetobacco plug24 may be substantially enclosed by theheating system22. In this embodiment, the heating system may include aheater40 that is received within a generallycylindrical shroud42. The actuation system ofFIG. 3 is like that ofFIG. 1 and includesconductors36,batteries37, and aswitch38.
• To provide one or more channels for air flow around theheater40, theheater40 and/or theshroud42 may include two or more radially outwardly extendingribs44,46 (seeFIG. 4) which are operable to space theheater40 from theshroud42. Theribs44,46 may extend longitudinally along the outer surface of theheater40. Theribs44,46, cooperate with theshroud42 and theheater40 to define a pair of preheating chambers orchannels48,50 through which air can enter the smoking system as indicated by the arrows inFIG. 3. At least one of theribs44,46 also extends axially beyond theheater40 and functions as a spacer to hold theheater40 away from theend wall52 of theshroud42.
• The cross-sectional area of thechannels48,50 may be selected as desired. For example, it may be desired to provide a flow area around theheater40 which is equivalent to the flow area through the inside of theheater40. Or, it may be desired to provide a flow area equivalent to the flow area through thetobacco plug24. Regardless of the flow area selected, theheater40 is preferably spaced from theend wall52 by a sufficient distance that the flow area at the inner end of theheater40 is at least as large as the flow area through thechannels48,50. In this manner, the puff resistance (resistance-to-draw) is defined by the tobacco plug rather than by the assembly of theheater40 and theshroud42.
• With the arrangement ofFIGS. 3 and 4, air entering the electric tobacco smoking system, seearrows54, flows axially through the preheating chambers orchannels48,50 between theheater40 and theshroud42. During that time, the air is heated by thermal energy that might otherwise escape from the outer surface of theheater40. That air then passes around the end of the heater, and flows through thetobacco plug24 where it picks up flavorful volatiles from the tobacco heated by theheater40. As theair54 leaves theheater40, it cools so that the volatiles condense and form theaerosol56 for delivery from theheating system22.
• If desired, the spacing between theheater40 and theshroud42 may be accomplished with structures other than the longitudinal ribs described above. For example, discontinuous ribs, radially extending pins, and baffles may be used as desired. Baffles might be used to improve heat transfer to air under some circumstances.
• Thus, the embodiment ofFIGS. 3 and 4 improves the heat transfer to air and is more efficient than embodiments without theshroud42.
• The electric tobacco smoking system of this disclosure may also include a mouthpiece60 (seeFIGS. 5 and 6) having an end in fluid communication with the tobacco mass. Themouthpiece60 may be constructed and arranged such that it has a cross-sectional configuration corresponding to the cross section of theheater assembly22. In addition, themouthpiece60 may include a generallycylindrical shell62 and anattachment sheath64. Theshell62 preferably extends outwardly from thetobacco plug24, has an open interior, and provides a channel or passage to deliver theaerosol32. Theshell62 also functions to provide structural support for theheater22 andtobacco plug24. Thesheath64 preferably surrounds theshell62 and may be constructed from paper or any other suitable conventional material.
• Thesheath64 extends beyond the end of theshell62 and into an opening within theheating assembly22, which opening may be between theheating assembly22 and the tobacco mass. By attaching thesheath64 to the electrictobacco smoking system20, the combination of thesmoking system20 and themouthpiece60 cosmetically resembles a conventional cigarette.
• When more than onemouthpiece60 will be used with thesmoking system20, or when onemouthpiece60 will be used with more than onesmoking system20, the sheath may be fabricated from a sufficiently rigid material that the mouthpiece can be removably attached to thesmoking system20 by inserting the extending portion of thesheath64 between theheating assembly22 and thetobacco plug24. For some applications, it may also be desirable to provide a suitable filter (not shown) such as a plug of cellulose acetate in the discharge end of themouthpiece60. Typically, such a filter would be located at an end of the mouthpiece. The actuation system ofFIG. 5 is like that ofFIG. 1 and includesconductors36,batteries37, and aswitch38; however, inFIG. 5, theswitch38 may be a puff sensing device or an air flow sensing device.
• Another arrangement for the heating assembly is shown inFIGS. 7 and 8. In this embodiment, the heating assembly includes anend piece70 and aprojection72. Theprojection72 may, for example, be a rod constructed and arranged so that it can be inserted into and received by thetobacco plug24. The axial length of theprojection72 is selected so that it does not extend all the way through the tobacco plug. The end piece orheater disk70 includes air passages oropenings74,76 through which air can be introduced into thetobacco plug24. At least one of theend piece70 and theprojection72 may be energized to generate heat, e.g., by resistance heating or induction heating. Presently it is contemplated that both theend piece70 and theprojection72 are capable of generating heat. However, if thetobacco plug24 has a small diameter compared to the transverse dimensions of theprojection72, sufficient heat may be generated by theprojection72 that additional heat from theend piece70 is not needed. The actuation system ofFIG. 7 is like that ofFIG. 1 and includesconductors36,batteries37, and aswitch38.
• While theend piece70 is depicted with two openings, the number, arrangement, and shape of the openings can vary. For example, a pattern of circular holes could be used if desired. Where theend piece70 is heated, heat transfer to the air passing through the openings can be increased by using smaller openings.
• If desired, theheating assembly70,72 and the associatedtobacco plug24 may be enclosed in other structures. For example, a cylindrical shell may surround the tobacco plug, or the tobacco plug along with theend piece70. Such a cylindrical shell could also include a mouthpiece portion.
• The embodiments discussed above include a generally cylindrical plug of tobacco; however, that shape for the tobacco is not critical. The cross section may be circular, as shown. Alternatively, the cross section can be uniform or non-uniform and can have any desired shape such a polygonal, elliptical, oval, toroidal, and the like. Moreover, the tobacco can have other suitable shapes as will be apparent to those skilled in the art. For example, the tobacco can be shaped as a pillow, i.e., a unit having a depth which is small compared with the transverse dimension. The pillow may be circular, rectangular, polygonal, polygonal with rounded corners, toroidal, or the like.
• A generally circular embodiment of the pillow arrangement is depicted inFIGS. 9 and 10. Here, thepillow80 is fashioned from cut filler tobacco. As desired, thepillow80 may include a permeable membrane surrounding it to hold its shape and facilitate handling. The thickness of thepillow80 may be in the range of 10-80% of a nominal transverse dimension of thepillow80. In the context ofFIG. 9, the nominal transverse dimension would be measured in the vertical direction and would correspond to the diameter of thepillow80. The pillow thickness would be measured in the horizontal direction, axially in the direction of airflow.
• Theheating system82 for this embodiment comprises a heating plate in heat transfer relationship with thetobacco pillow80. The actuation system ofFIG. 9 is like that ofFIG. 1 and includesconductors36,batteries37, and aswitch38. Theplate82 may be a generally circular disk and may include a plurality ofopenings84 to permit air to flow into thepillow80. Thoseopenings84 may have any desired shape. In some applications, theopenings84 will be sized to provide heat transfer from theheating plate82 to air (see arrows86) before the air enters thetobacco pillow80.
• Thermal energy from theplate82 is applied to thetobacco pillow80 by conduction and convection so that the temperature of the pillow is raised to release the flavorful volatiles. As with other embodiments, that temperature lies in the range of about 150° to about 220° C. As air leaves the tobacco pillow with the entrained flavorful volatiles (see arrows88), the flavorful volatiles cool to form an aerosol (see arrow90).
• Apillow80 having radial air inflow and axial outflow is shown inFIGS. 11 and 12. In this embodiment, the heating arrangement may include a disk-shapedheater92 and anannular heater94. Thedisk heater92 and theannular heater94 are spaced from one another by a distance corresponding to the thickness of thepillow80 and sandwich the pillow therebetween. Both thedisk heater92 and theannular heater94 have heat transfer relationship with thepillow80 so that theheaters92,94 can raise the temperature of tobacco in thepillow80 to a temperature sufficient to release the flavorful volatiles (i.e., about 150° to about 220° C.). The actuation system ofFIG. 11 is like that ofFIG. 1 and includesconductors36,batteries37, and aswitch38.
• In this arrangement, ambient air enters thepillow90 in a generally radial direction, for example, in response to inhalation. As the ambient air passes through thepillow80, its temperature rises by heat transfer from one or both of theheaters92,94 and it entrains volatiles released from the tobacco. Air with the flavorful tobacco volatiles, turns axially and leaves the assembly through a generally circular orifice or opening96 in the center of theannular heater94. The air with entrained tobacco volatiles cools as it leaves the heater and condenses to form an aerosol (arrow98).
• To enhance the heating efficiency of the embodiment ofFIGS. 11 and 12, the assembly of atobacco pillow80, thedisk heater92, and theannular heater94 may be enclosed in a housing100 (seeFIGS. 13 and 14). Thehousing100 may include awall102 fabricated from an insulating material to reduce heat loss from thedisk heater92. Preferably the insulatingwall102 is substantially coextensive with thedisk heater92. Thehousing100 also includes abaffle portion103 attached to the insulatingwall102 and operable to direct airflow into the tobacco mass. Thebaffle103 is spaced radially from both thedisk heater92 and theannular heater94. Moreover, thebaffle103 is spaced axially in front of theannular heater94. Although the actuation system is not schematically shown inFIG. 13, the actuation system forFIG. 13 is like that ofFIG. 1 and includes conductors, batteries, and a switch.
• With that arrangement, thebaffle103 forms aninternal channel104, which receives ambient air through anannular opening106 and directs that ambient air radially outwardly through a preheating passage, defined between theannular heater94 and the baffle, to a collector substantially surrounding the peripheral edge of thepillow80. As the air passes theannular heater94 in thechannel104, the air is heated thereby reducing energy loss or waste from theannular heater94. The heated air then passes radially inwardly through thepillow80 between thedisk heater92 and theannular heater94 and leaves through the generallycircular opening96.
• A generallycylindrical connector tube108 with a generally circular cross section is fitted into theopening96 and provides a passageway for heated air with entrained tobacco volatiles leaving thepillow80 through theopening96. In addition, thetube108 cooperates with thecentral opening110 of thebaffle103 to define anannular inlet opening106. As air leaves thetube108, it cools and the entrained tobacco volatiles form an aerosol.
• Use of a generally toriodal tobacco mass is depicted inFIGS. 15 and 16. Here, the structural characteristics of the electric tobacco heater are essentially the same as those of the heater described above in connection withFIGS. 13 and 14. Although the actuation system is not schematically shown inFIG. 15, the actuation system forFIG. 15 is like that ofFIG. 1 and includes conductors, batteries, and a switch. The principal difference being the tobacco mass, which is used. Here thetobacco mass120 is generally toroidally shaped, i.e., shaped like a donut. Thetobacco donut120 is sandwiched between thedisk heater92 and theannular heater94 so that the tobacco donut contacts both heaters. In this way, air is forced to travel through thetobacco donut120. Preferably, the tobacco donut does not extend outwardly to touch theshell103 so that the passageway for air is not obstructed.
• The electric tobacco heater (FIG. 15) is shown with amouthpiece122 attached at one end to thetube108. At the other end, themouthpiece122 may include asuitable filter124.
• It is also contemplated that the tobacco mass may be arranged so that successive portions of the tobacco mass can be advanced to the heating system. Individual tobacco mass portions may be used for a time corresponding generally to one puff, to multiple puffs, or to correspond to a time comparable to the smoking of a conventional cigarette. The embodiments ofFIGS. 9-12 are particularly well suited for such applications. For example, successive tobacco mass portions may be carried on a tape and advanced into position relative to the heating system by a suitable indexing arrangement. Alternatively, the tobacco mass portions may be carried by a cassette, or may comprise discrete packages.
• The terms and phases used herein are not to be interpreted with mathematical or geometric precision, rather geometric terminology is to be interpreted as meaning approximating or similar to the geometric terms and concepts. Where the term “about” is used in relation to a number, it is intended that such number has a tolerance of plus or minus 5%. Similarly, such terms as “generally” and “substantially” are intended to encompass both precise meanings of the associated terms and concepts as well as to provide reasonable latitude which is consistent with form, function, and/or meaning.
• It will now be apparent to those skilled in the art that this specification describes a new, useful, and nonobvious smokeless electric tobacco smoking system. It will also be apparent to those skilled in the art that numerous modifications, variations, substitutes, and equivalents exist for various aspects of the invention that have been described in the detailed description above. Accordingly, it is expressly intended that all such modifications, variations, substitutions, and equivalents that fall within the spirit and scope of the invention, as defined by the appended claims, be embraced thereby.

Claims (20)

1. A combustionless tobacco smoking system comprising:

a tobacco mass; and

heating apparatus, substantially enclosing the tobacco mass, electrically operated, operable to heat the tobacco mass to a temperature in the range of 150 to 220° C., defining a heat transfer channel through which air is directed.

2. The combustionless tobacco smoking system ofclaim 1 wherein:

(a) the tobacco mass has a rotationally symmetric shape;

(b) the tobacco mass is enclosed in a carrier; and/or

(c) at least part of the surface of the tobacco mass conforms to the heating apparatus.

3. The combustionless tobacco smoking system ofclaim 2, wherein:

(a) the tobacco mass has a generally cylindrical shape;

(b) the tobacco mass has a disk shape; or

(c) the tobacco mass is generally toroidal.

4. The combustionless tobacco smoking system ofclaim 3, wherein:

(a) the cylindrical shape is solid; or

(b) the cylindrical shape is hollow.

5. The combustionless tobacco smoking system ofclaim 2, wherein:

(a) the carrier is paper; or

(b) the carrier is a mesh material.

6. The combustionless tobacco smoking system ofclaim 2, wherein:

(a) the heating apparatus includes a substantially cylindrical heating element;

(b) the heater includes a rod, the rod being received by the tobacco mass;

(c) the heater includes a heater plate; and/or

(d) the heater includes an annular plate and a disk-shaped plate, and wherein the tobacco mass is sandwiched between the annular plate and the disk-shaped plate.

7. The combustionless tobacco smoking system ofclaim 6, further including a shroud which receives the substantially cylindrical heating element.

8. The combustionless tobacco smoking system ofclaim 7, wherein the substantially cylindrical heating element and the shroud define a preheating chamber for air.

9. The combustionless tobacco smoking system ofclaim 2, further including a mouthpiece having an end in fluid communication with the tobacco mass.

10. The combustionless tobacco smoking system ofclaim 9, wherein:

(a) the mouthpiece includes a second end having a filter; and/or

(b) the mouthpiece is attached between the tobacco mass and the heater.

11. The combustionless tobacco smoking system ofclaim 6, wherein the heater rod has an end extending from the tobacco mass, and wherein a heater disk is attached to the heater rod.

12. The combustionless tobacco smoking system ofclaim 11, wherein the heater disk includes air passages.

13. The combustionless tobacco smoking system ofclaim 6, wherein:

(a) the heater plate is generally circular; and/or

(b) the heater plate includes air passages therethrough.

14. The combustionless tobacco smoking system ofclaim 6, further including:

(a) an insulation plate generally coextensive with the heater plate; and/or

(b) a baffle substantially surrounding the tobacco mass and operable to direct airflow into the tobacco mass.

15. The combustionless tobacco smoking system ofclaim 14, further including an annular heating plate.

16. The combustionless tobacco smoking system ofclaim 15, wherein the baffle and the annular heating plate define a preheating passage.

17. The combustionless tobacco smoking system ofclaim 14, further including a connector tube which defines an airflow passage for air leaving the smoking system.

18. The combustionless tobacco smoking system ofclaim 17, further including a mouthpiece.

19. The combustionless tobacco smoking system ofclaim 18, wherein the mouthpiece includes a filter.

20. A method of producing a tobacco aerosol comprising:

establishing a stream of air;

contacting a tobacco mass with said stream of air while heating said tobacco mass to a temperature in the range of 150 to 220° C., defining a heat transfer channel through which air is directed.

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