An Aerosol Generating Article and an Aerosol Generating System

Abstract

An aerosol generating article for use with an aerosol generating device including a magnetic field generator includes first and second compartments configured to contain respectively a first aerosol generating substance and a second aerosol generating substance, and an inductively heatable susceptor configured to be inductively heated by the magnetic field generator. The inductively heatable susceptor has a first part positioned in the first compartment and a second part positioned in the second compartment. Each of the first and second aerosol generating substances includes a solid matrix and the first and second parts of the inductively heatable susceptor are secured in the solid matrix.

Claims

1. An aerosol generating article for use with an aerosol generating device including a magnetic field generator, the aerosol generating article comprising: first and second compartments containing respectively a first aerosol generating substance and a second aerosol generating substance; an inductively heatable susceptor configured to be inductively heated by the magnetic field generator, the inductively heatable susceptor having a first part positioned in the first compartment and a second part positioned in the second compartment; wherein each of the first and second aerosol generating substances comprises a solid matrix and the first and second parts of the inductively heatable susceptor are secured in the solid matrix.

2. The aerosol generating article according to claim 1, wherein the solid matrix of each of the first and second aerosol generating substances comprises at least one of a porous ceramic and a foam material.

3. The aerosol generating article according to claim 1, wherein the first and second parts of the inductively heatable susceptor are configured to be heated to first and second temperatures respectively, and one of the first and second temperatures is higher than the other of the first and second temperatures.

4. The aerosol generating article according to claim 3, wherein the first and second parts of the inductively heatable susceptor are positioned in use with respect to the magnetic field generator so that the first part is heated to the first temperature more rapidly than the second part is heated to the second temperature.

5. The aerosol generating article according to claim 1, wherein the first and second parts of the inductively heatable susceptor are separated from each other and both the first and second parts comprise an inductively heatable material.

6. The aerosol generating article according to claim 1, wherein the inductively heatable susceptor is a continuous susceptor in which the first and second parts are continuous with each other.

7. The aerosol generating article according to claim 6, wherein the first part of the inductively heatable susceptor comprises an inductively heatable material and the second part of the inductively heatable susceptor comprises a non-inductively heatable material which is configured to be heated conductively by heat generated in the first part.

8. The aerosol generating article according to claim 6, wherein the first and second compartments are separated by a partition wall and the continuous inductively heatable susceptor extends through the partition wall.

9. An The aerosol generating article according to claim 1, wherein one of the first and second aerosol generating substances releases a nicotine vapour when heated and the other of the first and second aerosol generating substances releases a second vapour when heated, and wherein the nicotine vapour reacts with the second vapour to form an aerosol comprising nicotine salt particles.

10. An aerosol generating system comprising: a magnetic field generator comprising a substantially helical induction coil; and the aerosol generating article according to claim 1, wherein: the first and second compartments are positioned inside the substantially helical induction coil; and the first part of the inductively heatable susceptor is positioned closer to an inner circumference of the substantially helical induction coil than the second part of the inductively heatable susceptor.

11. The aerosol generating system according to claim 10, wherein a distance between the first part of the inductively heatable susceptor and the inner circumference of the substantially helical induction coil is smaller than a distance between the first part of the inductively heatable susceptor and a central longitudinal axis of the substantially helical induction coil.

12. The aerosol generating system according to claim 10, wherein the first and second parts of the inductively heatable susceptor are plate susceptors which extend in a direction substantially parallel to a longitudinal axis of the substantially helical induction coil.

13. The aerosol generating system according to claim 10, wherein: the first and second parts of the inductively heatable susceptor are configured to be heated to first and second temperatures respectively, and one of the first and second temperatures is higher than the other of the first and second temperatures; and the first and second parts of the inductively heatable susceptor are positioned with respect to the magnetic field generator so that the first part is heated to the first temperature more rapidly than the second part is heated to the second temperature.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] FIG. 1 is a diagrammatic cross-sectional view of an aerosol generating device;

[0046] FIG. 2 is a diagrammatic cross-sectional view of a first example of an aerosol generating article for use with the aerosol generating device of FIG. 1; and

[0047] FIG. 3 is a diagrammatic cross-sectional view of a second example of an aerosol generating article for use with the aerosol generating device of FIG. 1.

DETAILED DESCRIPTION OF EMBODIMENTS

[0048] Embodiments of the present disclosure will now be described by way of example only and with reference to the accompanying drawings.

[0049] Referring initially to FIG. 1, there is shown diagrammatically an example of an aerosol generating device 10 for use with a “pod-type” aerosol generating article, and in particular the first and second examples of the aerosol generating articles 1, 2 illustrated in FIGS. 2 and 3. The aerosol generating device 10 has a proximal end 12 and a distal end 14 and comprises a device body 16 which includes a power source 18 and a controller 20 which may be configured to operate at high frequency. The power source 18 typically comprises one or more batteries which could, for example, be inductively rechargeable.

[0050] The aerosol generating device 10 is generally cylindrical and comprises a generally cylindrical aerosol generating space 22, for example in the form of a cavity, at the proximal end 12 of the aerosol generating device 10. The cylindrical aerosol generating space 22 is arranged to receive a correspondingly shaped generally cylindrical aerosol generating article 1, 2 as described below in connection with FIGS. 2 and 3.

[0051] The aerosol generating device 10 comprises a magnetic field generator 24 for generating an electromagnetic field. The magnetic field generator 24 comprises a substantially helical induction coil 26. The induction coil 26 has a circular cross-section, extends around the cylindrical aerosol generating space 22 and has a longitudinal axis. The induction coil 26 can be energised by the power source 18 and controller 20. The controller 20 includes, amongst other electronic components, an inverter which is arranged to convert a direct current from the power source 18 into an alternating high-frequency current for the induction coil 26.

[0052] The aerosol generating device 10 includes one or more air inlets 28 in the device body 16 which allow ambient air to flow into the aerosol generating space 22. The aerosol generating device 10 also includes a mouthpiece 30 having an air outlet 32. The mouthpiece 30 is removably mounted on the device body 16 at the proximal end 12 to allow access to the aerosol generating space 22 for the purposes of inserting or removing an aerosol generating article 1, 2.

[0053] Referring to FIG. 2, there is shown a first example of an aerosol generating article 1 for use with the aerosol generating device 10. The induction coil 26 of the aerosol generating device 10 is also shown in FIG. 2 to clearly indicate how the aerosol generating article 1 is positioned relative to the induction coil 26 when the aerosol generating article 1 is positioned in the aerosol generating space 22.

[0054] As noted above, the aerosol generating article 1 is a “pod-type” article and has a substantially circular bottom wall 40, a substantially circular top wall 42 and substantially cylindrical side wall 44. The bottom wall 40 and the top wall 42 are typically air-permeable and can include a plurality of openings or perforations or can comprise a material with a porous structure which allows air to flow through the bottom wall 40 and the top wall 42 without the need for the openings or perforations.

[0055] The aerosol generating article 1 comprises first and second compartments 46, 48. The first and second compartments 46, 48 are discrete compartments which are separated by a partition wall 50 that can be substantially fluid-impermeable.

[0056] The first and second compartments 46, 48 contain respectively a first aerosol generating substance 52 and a second aerosol generating substance 54, and in some embodiments one of the first and second aerosol generating substances 52, 54 can comprise a nicotine source and the other of the first and second aerosol generating substances 52, 54 can comprise a delivery enhancing compound, such as pyruvic acid or lactic acid. In the illustrated first example, one of the first and second aerosol generating substances 52, 54 is a type of solid or semi-solid material and typically comprises plant derived material, and in particular tobacco. One or both of the first and second aerosol generating substances 52, 54 may also comprise an aerosol-former.

[0057] The aerosol generating article 1 includes an inductively heatable susceptor 56 which is configured to be inductively heated by the magnetic field generator 24, and in particular by the induction coil 26. The inductively heatable susceptor 56 comprises a first part 58 positioned in the first compartment 46 and a second part 60 positioned in the second compartment 48. The inductively heatable susceptor 56 comprises a plate susceptor which is generally L-shaped, with the second part 60 extending in a direction which is substantially perpendicular to the first part 58. In the first example of the aerosol generating article 1, the second part 60 of the inductively heatable susceptor 56 extends through the partition wall 50 from the first compartment 46 into the second compartment 48.

[0058] In a first implementation, the first and second parts 58, 60 of the inductively heatable susceptor 56 both comprise an inductively heatable material. As will be understood by one of ordinary skill in the art, when the induction coil 26 is energised during use of the aerosol generating device 10, an alternating and time-varying electromagnetic field is produced. This couples with the first and second parts 58, 60 of the inductively heatable susceptor 56 and generates eddy currents and/or magnetic hysteresis losses in the inductively heatable susceptor 56 causing the first and second parts 58, 60 to heat up. The heat is transferred from the first part 58 of the inductively heatable susceptor 56 to the first aerosol generating substance 52 in the first compartment 46, for example by conduction, radiation and convection. In a similar manner, the heat is transferred from the second part 60 of the inductively heatable susceptor 56 to the second aerosol generating substance 54 in the second compartment 48, for example by conduction, radiation and convection. Thus, the first and second aerosol generating substances 52, 54 are heated independently by the corresponding first and second parts 58, 60 of the inductively heatable susceptor 56. The partition wall 50 can comprise a thermally insulating material that is configured to minimise heat transfer between the first and second compartments 46, 48, so that the heating of the first and second aerosol generating substances 52, 54 can be carefully controlled.

[0059] The first and second aerosol generating substances 52, 54 are heated by the corresponding first and second parts 58, 60 of the inductively heatable susceptor 56 without being burned. The heating of the first and second aerosol generating substances 52, 54 releases one or more volatile compounds and generates first and second vapours (e.g. a nicotine vapour and a second vapour) which tend to mix and which may react as they flow through the air outlet 32 and which cool and condense to form an aerosol which can be inhaled by a user of the aerosol generating device 10 through the mouthpiece 30.

[0060] In the first implementation, the first and second parts 58, 60 of the inductively heatable susceptor 56 are configured to have different orientations from each other with respect to the induction coil 26, for example by virtue of the L-shaped geometry of the inductively heatable susceptor 56, when the aerosol generating article 1 is positioned in the aerosol generating space 22. In particular, the first part 58 of the inductively heatable susceptor 56 is configured so that it extends in a direction that is substantially parallel to the longitudinal axis of the induction coil 26, thereby ensuring a strong electromagnetic coupling between the first part 58 and the induction coil 26. Conversely, the second part 60 of the inductively heatable susceptor 56 is configured so that it extends in a direction that is substantially perpendicular to the longitudinal axis of the induction coil 26 to provide a weaker electromagnetic coupling between the second part 60 and the induction coil 26. The stronger electromagnetic coupling between the first part 58 of the inductively heatable susceptor 56 and the induction coil 26 may enable the first part 58 to be inductively heated to a first temperature which is higher than a second temperature to which the second part 60 is inductively heated by virtue of the weaker electromagnetic coupling between the second part 60 and the induction coil 26. Alternatively or in addition, the first part 58 may be heated to the first temperature more rapidly than the second part 60 is heated to the second temperature by virtue of the stronger electromagnetic coupling between the first part 58 and the induction coil 26. By heating the first and second parts 58, 60 to different first and second temperatures and/or at different rates, the heating within the first and second discrete compartments 46, 48 can be adapted for the different first and second aerosol generating substances 52, 54 so that an aerosol with improved characteristics can be generated.

[0061] In a second implementation, the first part 58 of the L-shaped inductively heatable susceptor 56 comprises an inductively heatable material and the second part 60 of the inductively heatable susceptor 56 comprises a non-inductively heatable material. Accordingly, when the induction coil 26 is energised during use of the aerosol generating device 10, the electromagnetic field generated by the induction coil 26 couples with the first part 58 of the inductively heatable susceptor 56 and inductively heats the first part 58 to a first temperature in the manner described above. A proportion of the heat generated in the first part 58 is transferred to the first aerosol generating substance 52 in the first compartment 46, for example by conduction, radiation and convection. A proportion of the heat generated in the first part 58 is also transferred by conduction to the second part 60, so that the second part 60 is heated conductively to a second temperature by the heat generated in the first part 56. Because the second part 60 is heated conductively, rather than inductively, the second part 60 is typically heated to a lower second temperature than the first temperature to which the first part 58 is inductively heated and/or the second part 60 is heated at a slower rate than the first part 58.

[0062] Referring to FIG. 3, there is shown a second example of an aerosol generating article 2 for use with the aerosol generating device 10. The induction coil 26 of the aerosol generating device 10 is also shown in FIG. 3 to clearly indicate how the aerosol generating article 2 is positioned relative to the induction coil 26 when the aerosol generating article 2 is positioned in the aerosol generating space 22. The aerosol generating article 2 is similar to the aerosol generating article 1 described above with reference to FIG. 2, and corresponding components are identified using the same reference numerals.

[0063] The aerosol generating article 2 comprises first and second compartments 46, 48 separated by a partition wall 50 and an inductively heatable susceptor 56 having first and second parts 58, 60. The first compartment 46 contains a first aerosol generating substance 52 and the first part 58 of the inductively heatable susceptor 56. The second compartment 48 contains a second aerosol generating substance 54 and the second part 60 of the inductively heatable susceptor 56.

[0064] Each of the first and second aerosol generating substances 52, 54 comprises a solid matrix 62, 64 and the first and second parts 58, 60 of the inductively heatable susceptor 56 are secured respectively in each solid matrix 62, 64. Each solid matrix 62, 64 typically comprises at least one of a porous ceramic and a foam material, for example in the form of a reconstituted tobacco mousse or an e-liquid mousse, which ensures that the first and second parts 58, 60 of the inductively heatable susceptor 56 are held securely in place in the respective first and second compartments 46, 48.

[0065] The first and second parts 58, 60 of the inductively heatable susceptor can be separate inductively heatable parts which are separated from each other in the first and second compartments 46, 48 and both of the first and second parts 58, 60 can comprise an inductively heatable material. When the aerosol generating article 2 is positioned in the aerosol generating space 22 during use of the aerosol generating device 10 and the induction coil 26 is energised, an alternating and time-varying electromagnetic field is produced. This couples with the first and second parts 58, 60 of the inductively heatable susceptor 56 and generates eddy currents and/or magnetic hysteresis losses in the inductively heatable susceptor 56 causing the first and second parts 58, 60 to heat up independently. The heat is transferred from the first part 58 of the inductively heatable susceptor 56 to the first aerosol generating substance 52 in the first compartment 46, for example by conduction, radiation and convection. In a similar manner, the heat is transferred from the second part 60 of the inductively heatable susceptor 56 to the second aerosol generating substance 54 in the second compartment 48, for example by conduction, radiation and convection. Thus, the first and second aerosol generating substances 52, 54 are heated independently by the corresponding first and second parts 58, 60 of the inductively heatable susceptor 56.

[0066] The first and second aerosol generating substances 52, 54 are heated by the corresponding first and second parts 58, 60 of the inductively heatable susceptor 56 without being burned. The heating of the first and second aerosol generating substances 52, 54 releases one or more volatile compounds and generates first and second vapours which tend to mix as they flow through the air outlet 32 and which cool and condense to form an aerosol which can be inhaled by a user of the aerosol generating device 10 through the mouthpiece 30.

[0067] As will be apparent from FIG. 3, the first and second parts 58, 60 of the inductively heatable susceptor 56 are plate susceptors and are both arranged so that they extend in a direction substantially parallel to the longitudinal axis of the induction coil 26, which is the optimum orientation for coupling with the electromagnetic field generated by the induction coil 26. In addition, the first part 58 is positioned closer to an inner circumference of the induction coil 26 than the second part 60 and due to the fact that the magnetic flux density increases from a minimum along a central longitudinal axis of the induction coil 26 to a maximum close to the inner circumference of the induction coil 26, the first part 58 of the inductively heatable susceptor 56 is inductively heated to a first temperature which is higher than a second temperature to which the second part 60 is inductively heated. Alternatively or in addition, the first part 58 may be heated to the first temperature more rapidly than the second part 60 is heated to the second temperature by virtue of its closer proximity to the inner circumference of the induction coil 26. As explained above, by heating the first and second parts 58, 60 to different first and second temperatures and/or at different rates, the heating within the first and second compartments 46, 48 can be adapted for the different first and second aerosol generating substances 52, 54 so that an aerosol with improved characteristics can be generated.

[0068] Although exemplary embodiments have been described in the preceding paragraphs, it should be understood that various modifications may be made to those embodiments without departing from the scope of the appended claims. Thus, the breadth and scope of the claims should not be limited to the above-described exemplary embodiments.

[0069] Any combination of the above-described features in all possible variations thereof is encompassed by the present disclosure unless otherwise indicated herein or otherwise clearly contradicted by context. For example, the L-shaped inductively heatable susceptor 56 described in connection with the first example of FIG. 2 could be employed in the second example of FIG. 3, such that the first and second parts 58, 60 are secured in a solid matrix 62, 64 provided in each of the first and second compartments 46, 48. In this case, both the first and second parts 58, 60 of the inductively heatable susceptor 56 could comprise an inductively heatable material or the first part 58 could comprise an inductively heatable material whilst the second part 60 could comprise a non-inductively heatable material which is heated conductively by the first part 58. Conversely, an inductively heatable susceptor 56 comprising separate first and second parts 58, 60 as described in connection with the second example of FIG. 3 could be employed in the first example of FIG. 2.

[0070] Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like, are to be construed in an inclusive as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.