LIQUID-CONVEYING SUSCEPTOR ASSEMBLY FOR CONVEYING AND INDUCTIVELY HEATING AN AEROSOL-FORMING LIQUID

Abstract

A liquid-conveying susceptor assembly is provided for conveying and inductively heating an aerosol-forming liquid under an influence of an alternating magnetic field, the assembly including: an array of inductively heatable longitudinal filaments arranged side by side; and an array of transverse filaments arranged side by side and crossing the longitudinal filaments transverse to a length extension of the longitudinal filaments, in which the transverse filaments only extend along a length portion of the longitudinal filaments such that the assembly further includes at least one grid portion and at least one non-grid portion, in which in the grid portion the transverse filaments and the longitudinal filaments cross each other, in which in the non-grid portion the assembly only includes the longitudinal filaments, but no transverse filaments, and in which length dimension of the non-grid portion is at least 20 percent of a length dimension of the longitudinal filaments.

Claims

1.-15. (canceled)

16. A liquid-conveying susceptor assembly for conveying and inductively heating an aerosol-forming liquid under an influence of an alternating magnetic field, the liquid-conveying susceptor assembly comprising: an array of inductively heatable longitudinal filaments arranged side by side; and an array of transverse filaments arranged side by side and crossing the array of inductively heatable longitudinal filaments transverse to a length extension of the inductively heatable longitudinal filaments, wherein the array of transverse filaments only extends along a length portion of the array of inductively heatable longitudinal filaments such that the liquid-conveying susceptor assembly further comprises at least one grid portion and at least one non-grid portion, wherein in the grid portion the array of transverse filaments and the array of inductively heatable longitudinal filaments cross each other, wherein in the non-grid portion the liquid-conveying susceptor assembly only comprises the inductively heatable longitudinal filaments, but no transverse filaments, and wherein a length dimension of the at least one non-grid portion along the length extension of the inductively heatable longitudinal filaments is C 20 percent of a length dimension of the inductively heatable longitudinal filaments.

17. The liquid-conveying susceptor assembly according to claim 16, wherein the at least one grid portion is located at one of two longitudinal end portions of the array of inductively heatable longitudinal filaments, or wherein the at least one grid portion is located between both of the two longitudinal end portions of the array of inductively heatable longitudinal filaments.

18. The liquid-conveying susceptor assembly according to claim 16, wherein the at least one non-grid portion is located at a longitudinal end portion of the array of inductively heatable longitudinal filaments, or wherein the at least one non-grid portion is located between both of two longitudinal end portions of the array of inductively heatable longitudinal filaments.

19. The liquid-conveying susceptor assembly according to claim 16, wherein a length dimension of the non-grid portion along the length extension of the inductively heatable longitudinal filaments is at least 30 percent of a length dimension of the inductively heatable longitudinal filaments.

20. The liquid-conveying susceptor assembly according to claim 16, wherein a length dimension of the non-grid portion along the length extension of the inductively heatable longitudinal filaments is at least 80 percent of a length dimension of the inductively heatable longitudinal filaments.

21. The liquid-conveying susceptor assembly according to claim 16, wherein a length dimension of the grid portion along the length extension of the inductively heatable longitudinal filaments is at most 90 percent of a length dimension of the inductively heatable longitudinal filaments.

22. The liquid-conveying susceptor assembly according to claim 16, wherein a length dimension of the grid portion along the length extension of the inductively heatable longitudinal filaments is at most 20 percent of a length dimension of the inductively heatable longitudinal filaments.

23. The liquid-conveying susceptor assembly according to claim 16, wherein the array of inductively heatable longitudinal filaments has a substantially cylindrical shape or a substantially hollow cylindrical shape or a substantially conical shape or a substantially frusto-conical shape or a substantially hollow conical shape or a substantially hollow frusto-conical shape.

24. The liquid-conveying susceptor assembly according to claim 16, wherein the array of transverse filaments has a substantially ring shape.

25. The liquid-conveying susceptor assembly according to claim 16, wherein a mean center-to-center distance between adjacent inductively heatable longitudinal filaments is in a range between 0.1 millimeter and 2 millimeters.

26. The liquid-conveying susceptor assembly according to claim 16, wherein a mean center-to-center distance between adjacent inductively heatable longitudinal filaments is in a range between 0.025 millimeter and 0.5 millimeter.

27. The liquid-conveying susceptor assembly according to claim 16, wherein at least one of the inductively heatable longitudinal filaments and the transverse filaments comprise one or more first filaments including a first susceptor material, and a plurality of second filaments including a second susceptor material, and wherein the second susceptor material comprises one of a ferrimagnetic material or a ferromagnetic material.

28. The liquid-conveying susceptor assembly according to claim 16, further comprising a fan-out portion at at least one longitudinal end portion of the array of the inductively heatable longitudinal filaments, wherein the inductively heatable longitudinal filaments diverge from each other.

29. An inductive heating assembly for conveying and inductively heating an aerosol-forming liquid, the inductive heating assembly comprising: at least one liquid-conveying susceptor assembly according to claim 16; and at least one induction source configured and arranged to generate an alternating magnetic field in a heating section of the at least one liquid-conveying susceptor assembly.

30. The inductive heating assembly according to claim 29, wherein the at least one induction source is further configured and arranged to generate the alternating magnetic field in a heating section of the non-grid portion.

31. The inductive heating assembly according to claim 30, wherein the heating section of the non-grid portion has a length of at least 5 percent of a length dimension of the non-grid portion along the length extension of the inductively heatable longitudinal filaments.

32. The inductive heating assembly according to claim 30, wherein the heating section of the non-grid portion has a length of at least 80 percent of a length dimension of the non-grid portion along the length extension of the inductively heatable longitudinal filaments.

33. An aerosol-generating article for an inductively heatable aerosol-generating device, the aerosol-generating article comprising: at least one reservoir comprising an outlet and being configured to store aerosol-forming liquid; and at least one liquid-conveying susceptor assembly according to claim 16 and being configured to deliver the aerosol-forming liquid from the at least one reservoir through the outlet into a region outside the at least one reservoir.

34. The aerosol-generating article according to claim 33, wherein the at least one liquid-conveying susceptor assembly comprises at least one soaking section arranged in the at least one reservoir, and wherein the at least one soaking section is part of the grid portion or wherein the grid portion is part of the at least one soaking section.

35. An aerosol-generating system, comprising: an inductively heatable aerosol-generating device; an aerosol-generating article for the aerosol-generating device; and an inductive heating assembly according to claim 29, wherein the at least one induction source of the inductive heating assembly is part of the inductively heatable aerosol-generating device, and wherein the at least one liquid-conveying susceptor assembly of the inductive heating assembly is part of the aerosol-generating article.

Description

[0172] Examples will now be further described with reference to the figures in which:

[0173] FIG. 1 schematically illustrates an inductive heating assembly comprising a susceptor assembly according to a first embodiment of the present invention;

[0174] FIG. 2 shows a cross-section through the susceptor assembly according to FIG. 1 along line A-A;

[0175] FIG. 3 shows a cross-section through the susceptor assembly according to FIG. 1 along line B-B;

[0176] FIG. 4 schematically illustrates a susceptor assembly according to a second embodiment of the present invention;

[0177] FIG. 5 schematically illustrates a susceptor assembly according to a third embodiment of the present invention;

[0178] FIG. 6 schematically illustrates a susceptor assembly according to a fourth embodiment of the present invention;

[0179] FIG. 7 schematically illustrates a susceptor assembly according to a fifth embodiment of the present invention;

[0180] FIG. 8 schematically illustrates an exemplary embodiment of an aerosol-generating article according to the present invention; and

[0181] FIG. 9 schematically illustrates an exemplary embodiment of an aerosol-generating system according to the present invention.

[0182] FIG. 1 schematically illustrates an inductive heating assembly 1 comprising a liquid-conveying susceptor assembly 10 according to a first embodiment of the present invention. In general, the susceptor assembly 10 comprises two filament arrays 20, 30 crossing each other only partially such that the susceptor assembly 10 comprises one grid portion 11, in which the two filament arrays 20, 30 cross each other, and a non-grid portion 12, in which the two filament arrays 20, 30 do not cross each other.

[0183] In the present embodiment, one of the two arrays 20, 30 is formed by an array 20 of inductively heatable longitudinal filaments 21, 22 which are arranged parallel to each other side by side in a hollow cylindrical configuration in which the longitudinal filaments 21, 22 extend substantially along the cylinder axis forming the wall of the hollow cylindrical configuration. The other array is formed by an array 30 of transverse filaments 31, 32 which are arranged side by side in the form of a plurality of circular rings circumferentially surrounding the hollow cylindrical configuration of the array 20 of longitudinal filaments 21, 22 such as to cross the array 20 of longitudinal filaments 21, 22, transverse to a length extension of the longitudinal filaments 21, 22. According to the invention, the array 30 of transverse filaments 31, 32 only extends along a length portion of the array 20 of longitudinal filaments 21, 22 such that the susceptor assembly 10 comprises a grid portion 11 and a non-portion 12, as described above.

[0184] The susceptor assembly 10 is capable to perform two functions: conveying and heating aerosol-forming liquid. For that purpose, the array 20 comprises a plurality of first filaments 21 and a plurality of second filaments 22, wherein the plurality of first filaments 21 comprise a first susceptor material and the plurality of second filaments 22 comprise a second susceptor material. Likewise, the array 30 comprises a plurality of first filaments 31 and a plurality of second filaments 32, wherein the plurality of first filaments 32 comprise the first susceptor material in the plurality of second filaments 32 comprises a second susceptor material. Preferably, the first and the second susceptor materials of the filaments 21, 22, 31, 32 of both arrays 20, 30 are identical. Due to the susceptive nature of the filament materials, the first filaments 21, 32 and the second filaments 22, 32 are capable to be inductively heated in an alternating magnetic field and thus to heat an aerosol-forming liquid in thermal contact with the filaments. Furthermore, due to the arrangement of the first and second filaments 21, 22, 31, 32 and the susceptor assembly 10 and due to the small diameter of the filaments 21, 22, 31, 32, narrow spaces are formed between the filaments 21, 22, 31, 32 which provide capillary action in both portions, in the grip portion 11 and the non-grid portion 12, in particular along the longitudinal direction X of the susceptor assembly 10. Thus, as an example, if one longitudinal end portion 23 of the array 20 of longitudinal filaments 21, 22 is immersed into an aerosol-forming liquid, liquid may be conveyed to the opposite longitudinal end portion 24 the array 20 of longitudinal filaments 21, 22, where the conveyed liquid may be vaporized and exposed to an air path to be drawn out as an aerosol.

[0185] For vaporizing the liquid, the heating assembly 1 further comprises an induction source 3 including an induction coil 4. In the present embodiment, the induction coil 4 is a double-layer helical coil, each layer having six windings, which is capable to generate a substantially homogeneous alternating magnetic field. As can be seen in FIG. 1, the induction coil 4 is arranged around the end portion 24 of the filament bundle 18 such as to generate an alternating magnetic field which locally penetrates the susceptor assembly at the longitudinal end portion 24 only. As a consequence, the susceptor assembly 10 is locally heated in a heating section 17 at the longitudinal end portion 24. Due the missing transverse filaments, the non-grid portion 11 only comprises those filaments 21, 22 whose geometry and orientation is optimized with regard to the orientation of the alternating magnetic field used for heating the susceptor assembly. In particular, the longitudinal filaments 21, 22 are arranged substantially parallel to the magnetic field penetrating the susceptor assembly 10 at the longitudinal end portion 24.

[0186] In contrast, the array 30 of transverse filaments 31, 32 primarily only serves to keep the array 20 of longitudinal filaments 21, 22 such as to provide a good filament bond as well as an improved mechanical and dimensional stability of the susceptor assembly 10.

[0187] The strength of the magnetic field is chosen such that heating section 17 is heated up to temperature sufficient to vaporize the aerosol-forming liquid conveyed through the susceptor assembly 10. In contrast, due to the only local heating, the remaining section 16 of the susceptor assembly 10, in particular the longitudinal end portion 23 stays at temperatures below the vaporization temperature. Hence, in use of the heating assembly 1, the susceptor assembly 10 comprises a temperature profile along its length direction X with sections of higher and lower temperatures as shown in the lower part of FIG. 1. More specifically, the temperature profile shows a temperature increase from the longitudinal end portion 23 to the heating section 17 at the opposite longitudinal end portion 24, from temperatures below a vaporization temperature T_vap of the aerosol-forming liquid to temperatures above the respective vaporization temperature T_vap. Advantageously, having the remaining section 16 below the vaporization temperature T_vap prevents boiling of aerosol-forming liquid within that part of the susceptor assembly 10. Even more, in case the remaining section 16 or at least a part of thereof is used as a soaking section 16 to be immersed into a liquid reservoir, boiling of aerosol-forming liquid within the reservoir is also prevented. As can be seen in FIG. 1, the heating section 17 is part of the non-grid portion 12, whereas the grid portion 12 is part of the remaining section 16 which may be used as soaking section 16.

[0188] The actual temperature profile forming up in use of the susceptor assembly 10 depends on the thermal conductivity and the length dimension of the array 20 of longitudinal filaments 21, 22. Accordingly, in order to have sufficient temperature gradient between the longitudinal end portion 23 and the longitudinal end portion 24, the longitudinal filaments 21, 22 require a certain total length. With regard to the present embodiment, the length dimension of the longitudinal filaments 21, 22 may be in a range between 5 millimeter and 50 millimeter, in particular between 10 millimeter and 40 millimeter, preferably between 10 millimeter and 30 millimeter, more preferably between 10 millimeter and 20 millimeter. This applies for each filament type, that is, the plurality of first filaments 21 and the plurality of second filaments 22.

[0189] FIG. 2 shows a cross-section through the susceptor assembly 10 along line A-A in FIG. 1, that is, through the non-grid portion 12. Likewise, FIG. 3 shows a cross-section through the susceptor assembly 10 along line B-B in FIG. 1, that is, through the grid portion 11. Both, the plurality of first filaments 21, 31 and the plurality of second filaments 22 of each array 20, 30 are solid material filaments having a substantially circular cross-section. Due to the specific filament arrangement, capillary spaces are formed between the pluralities of filaments 21, 22, 31, 32. Other cross-sectional shapes of the plurality of first and second filaments 21, 22, 31, 32 of are also possible, for example, oval, elliptical triangular rectangular, quadratic, hexagonal or polygonal cross-sections.

[0190] In order to provide a sufficient capillary action, the mean center-to-center distance D20 between adjacent longitudinal filaments 21, 22 may be in a range between 0.1 millimeter and 0.2 millimeter. Likewise, as indicated in FIG. 1, the mean center-to-center distance D30 between adjacent transverse filaments 31, 32 is at most 1 millimeter, preferably at most 0.5 millimeter.

[0191] The capillary action is promoted also by a small radius of curvature, and thus by a small diameter of the first and second filaments 21, 22, 31, 32. Accordingly, the first and second filaments 21, 22, 31, 32 may have a diameter of at most 0.025 millimeter, at most 0.05 millimeter, at most 0.1 millimeter, at most 0.15 millimeter, at most 0.2 millimeter, at most 0.25 millimeter, at most 0.3 millimeter, at most 0.35 millimeter, at most 0.4 millimeter, at most 0.45 millimeter or at most 0.5 millimeter. However, the diameter of the first and second filaments 21, 22, 31, 32 should be still larger than twice the skin depth in order to induce a sufficient amount of eddy currents and thus to generate a sufficient amount of heat energy when the susceptor assembly 10 is exposed to an alternating magnetic field. Accordingly, depending on the materials and the frequency of the alternating magnetic field used, the first and second filaments 11, 12 may have a diameter of at least 0.015 millimeter, at least 0.02 millimeter, at least 0.025 millimeter at least 0.05 millimeter, at least 0.075 millimeter, at least 0.1 millimeter, at least 0.125 millimeter, at least 0.15 millimeter, at least 0.2 millimeter, at least 0.3 millimeter or at least 0.4 millimeter.

[0192] In the present embodiment, the first and second filaments 21, 22, 31, 32 of both areas 20, 30 comprise a liquid-adhesive surface coating (not shown). The liquid adhesive surface coating further enhances capillary action of the susceptor assembly 10.

[0193] The first susceptor material of the plurality of first filaments 21, 31 is optimized with regard to heat generation. For example, the first susceptor material may be a ferromagnetic stainless steel causing the plurality of first filaments 21, 31 to be inductively heated by eddy currents as well as by hysteresis losses. The Curie temperature of the ferromagnetic first susceptor material is chosen such as to be above the vaporization temperature, preferably above 300 degree Celsius. In contrast, as described further above, the plurality of second filaments 22, 32 mainly serve as temperature markers. For that purpose, the second susceptor material may be a ferromagnetic or ferrimagnetic material which preferably has a Curie temperature at about a predefined operating temperature of the susceptor assembly 10. Accordingly, when the susceptor assembly 10 reaches the Curie temperature of the second susceptor material, the magnetic properties of the second susceptor material change from ferromagnetic or ferrimagnetic to paramagnetic, accompanied by a temporary change of its electrical resistance. Thus, by monitoring a corresponding change of the electrical current absorbed by the induction source 3 that is used to generate the alternating magnetic field it can be detected when the second susceptor material has reached its Curie temperature and, thus, when the predefined operating temperature has been reached. Suitable materials for the second susceptor material may be mu-metal or permalloy. To sufficiently work as temperature markers, only a few second filaments 22, 32 are required. Accordingly, the number of first filaments 21 may be larger, in particular two times or three times or four times or five times or six times or seven times or eight times or nine times or ten times larger than the number of second filaments 12. In the present embodiment, the array 20 of longitudinal filaments 21, 22 exemplarily comprises fifteen first filaments 21 and four second filaments 12. Likewise, the array 30 of transverse filaments 31, 32 exemplarily comprises six first filaments 31 and one second filament 32. However, since the grid portion 11 is not intended to be heated, the array 30 of transverse filaments does not necessarily need to comprise any second filaments 32. Even more, the array 30 of transverse filaments does not necessarily need to comprise any filaments being inductively heatable.

[0194] As can be also seen in FIG. 2, the plurality of second filaments 22 are randomly distributed throughout the array 20 of longitudinal filaments 21, 22. Advantageously, a random distribution requires only little effort during manufacturing of the susceptor assembly 10. As can be further seen in FIG. 2, the array 20 of longitudinal filaments 21, 22 has a substantially circular, in particular ring-shaped cross-section which is particularly easy to manufacture.

[0195] Again with reference to FIG. 1, the first and second filaments 21, 22 are arranged in parallel to each other such as to form a parallel-bundle portion along the entire length extension of the array 20 of longitudinal filaments 21, 22. That is, the array 20 of longitudinal filaments 21, 22 is an unstranded in which the first and second filaments 21, 22 are neither stranded nor twisted and, thus, do not cross each other. The parallel-bundling is particularly advantageous to provide sufficient capillary action along the entire length extension of the array 20 of longitudinal filaments 21, 22. Furthermore, such a susceptor assembly 10 is easy and cost-effective to manufacture.

[0196] FIG. 4 shows a second embodiment of the susceptor assembly 110 according to the present invention. In general, the susceptor assembly 110 according to FIG. 4 is similar to the susceptor assembly 10 shown in FIG. 1-3. Therefore, identical or similar features are denoted with the same reference signs, yet incremented by 100. In contrast to the first embodiment shown in FIG. 1-3, the array 130 of transverse filaments 131 of the susceptor assembly 110 according to FIG. 4 is divided into parts. This configuration results in a susceptor assembly comprising one non-grid portion 112 that is located between both longitudinal end portions 123, 124 of the array 120 of longitudinal filaments 121, 122, and two grid portions 111 at the longitudinal end portions of the array of longitudinal filaments 123, 124, one at each end. Advantageously, the two grid portions 111 at each longitudinal end portion 123, 124 may be used as soaking sections for conveying as a form liquid from two sides towards the non-grid portion 112 where the aerosol-forming liquid may be vaporized. Due to this, the liquid conveying capacity of the susceptor assembly 110 is increased. Further in contrast to the susceptor assembly 10 according to FIG. 1-3, the array 130 of transverse filaments 131 only comprises one type of filaments which necessarily do not need to be inductively heatable.

[0197] FIG. 5 shows a third embodiment of the susceptor assembly 210 according to the present invention. In general, the susceptor assembly 210 according to FIG. 5 is similar to the susceptor assembly 10 shown in FIG. 1-3. Therefore, identical or similar features are denoted with the same reference signs, yet incremented by 200. In contrast to the first embodiment shown in FIG. 1-3, the susceptor assembly 210 recorded FIG. 5 has a substantially frusto-conical shape, in particular a substantially hollow frusto-conical shape. In this configuration, the length axis of the frustoconical shape extends substantially along the length extension of the longitudinal filaments. However, the array 220 of longitudinal filaments 221, 222 forms the shell surface of the frustoconical shape.

[0198] FIG. 6 shows a fourth embodiment of the susceptor assembly 310 according to the present invention which is similar to the susceptor assembly 210 according to FIG. 5. Therefore, identical or similar features are denoted with the same reference signs, yet incremented by 100. In contrast to the third embodiment shown in FIG. 5, the susceptor assembly 310 according to FIG. 6 has a substantially conical shape, in particular hollow conical shape, in which the longitudinal filaments 321, 322 converge at one of the longitudinal end portion 323 of the array 320 of longitudinal filaments 321, 322.

[0199] With reference to both embodiments shown in FIG. 5 and FIG. 6, a conical or frusto-conical shape provides an inherent mechanical dimensional stability. Furthermore, the longitudinal filaments 321, 322, 421, 422 diverge from each other towards the base of the conical shape or frustoconical shape. Accordingly, a conical or frustoconical array of longitudinal filaments facilitates providing a fan-out portion at one longitudinal end portion 224, 324 of the array 320 of longitudinal filaments 321, 322.

[0200] FIG. 7 shows a fifth embodiment of the susceptor assembly 410 according to the present invention which is similar to the susceptor assembly 210 according to FIG. 5. Therefore, identical or similar features are denoted with the same reference signs, yet incremented by 200. In contrast to the third embodiment shown in FIG. 5, the susceptor assembly 310 according to FIG. 6 has a substantially cylindrical, in particular substantially hollow cylindrical shape along the grid portion 411 at the longitudinal end portion 423 of the array 420 of longitudinal filaments 421, 422. In contrast, in the grid portion 412, longitudinal filaments 421, 422 are curved such as to diverge from each towards the opposite longitudinal end portion 423 of the array 420 of longitudinal filaments 421, 422. As a result, like the susceptor assembly 220 shown in FIG. 5, the susceptor assembly 410 according to FIG. 7 also comprises a fan-out portion at the longitudinal end portion 424 of the array 420 of longitudinal filaments 421, 322. To this extent, the susceptor assembly 410 according to FIG. 7 may also considered as to have a frustoconical shape including a shell surface which is curved along the length extension of the longitudinal filaments 421, 422.

[0201] In any of these configurations shown in FIG. 4-7, the array of transverse filaments preferably has a substantially ring shape. That is, the transverse filaments extend along the circumference of the cylindrical, conically, or frustoconically (in particular hollow-cylindrical, hollow-conically or hollow-frustoconically) shaped array of longitudinal filaments in the grid portions 111, 211, 311, 411 of the susceptor assembly 110, 210, 310, 410.

[0202] FIG. 8 schematically illustrates an exemplary embodiment of an aerosol-generating article 40 according to the present invention. As will be described further below with regard to FIG. 9, the aerosol-generating article 40 is configured for use with an inductively heating aerosol-generating device. The article comprises 40 comprises a rigid article housing 43 made of a liquid impermeable material. Together with a bushing 44 the article housing 43 forms a liquid reservoir 41 which contains an aerosol-forming liquid 51. The bushing 44 comprises an ring-shaped opening forming an outlet of the liquid reservoir 41. The article 40 further comprises a liquid-conveying susceptor assembly 10 which substantially corresponds to the susceptor assembly 10 shown in FIG. 1-3. The hollow-cylindrical susceptor assembly 10 passes through the ring-shaped opening in the bushing 44 such as to be partially arranged in the liquid reservoir 41 and partly arranged in a vaporization cavity 45 which is formed by the article housing 43 and the bushing 44 adjacent to the liquid reservoir 41. Due to this, the susceptor assembly 10 is capable to deliver aerosol-forming liquid 51 from the liquid reservoir 41 through the outlet into a region outside the liquid reservoir 41, that is, into the vaporization cavity 45. There, the conveyed liquid 51 may be vaporized by inductively heating that part of the filament bundle 18 which is arranged in the vaporization cavity 45. Accordingly, that part of the filament bundle 18, which includes the grid-portion 11 and is arranged in the liquid reservoir 41 such as to be immersed into the aerosol-forming liquid 51, acts as a soaking section 16. The length of the soaking section 16 may be advantageously used to a control the amount of aerosol-forming liquid being soaked and conveyed from the liquid reservoir 41 into the vaporization cavity 45. In the present embodiment, the soaking section 16 has a length of about 60% of the total length of the filament bundle 18.

[0203] Likewise, that part of the susceptor assembly, which is part of the non-grid-portion 12 and is arranged in the vaporization cavity 45, acts at least partially as a heating section 17 when being exposed to an alternating magnetic field as described before with regard to FIG. 1.

[0204] As can be further seen in FIG. 8, the article 40 comprises air inlets 46 through the article housing 43 into the vaporization cavity 45 enabling air to enter into the vaporization cavity 45. The air inlet 46 may be configured to provide airflow at or around the heating section 16 of the susceptor assembly 10. The air inlet 46 may be a hole through the reservoir body. Likewise, the air inlet 46 may be a nozzle that is configured to direct airflow to a specific target location at the susceptor assembly 10. In addition, the article 41 comprises a mouthpiece 47 forming the proximal end portion of the vaporization cavity 45. The mouthpiece 47 has a tapered shape including an air outlet 48 at its very end, thus allowing a user to directly inhale an aerosol from the article. Preferably, the mouthpiece comprises a filter (not shown). Hence, when a user takes a puff, aerosol-forming liquid vaporized from the heating section 17 is exposed to the airflow having entered the vaporization cavity 45 through the air inlets 46 such as to form an aerosol which may be drawn out through the air outlet 48 in the mouthpiece 47.

[0205] In general, the aerosol-generating article 40 may be an aerosol-generating article for single use or an aerosol-generating article for multiple uses. In the latter case, the aerosol-generating article 40 may be refillable. That is, the liquid reservoir 41 may be refillable with aerosol-forming liquid 51 after depletion.

[0206] FIG. 9 schematically illustrates an exemplary embodiment of an aerosol-generating system 80 according to the present invention. The system 80 comprises an inductively heating aerosol-generating device 60 and an aerosol-generating article 40 for use with the device 60. In the present embodiment, the aerosol-generating article 40 corresponds to the article shown in FIG. 8. In particular, the article 40 comprises a susceptor assembly 10 for conveying and heating aerosol-forming liquid 51 contained in the article 40. The aerosol-generating device 60 is an electrically operated device that is capable of interacting with the article 40 in order to generate an aerosol by inductively heating the aerosol-forming liquid via the susceptor assembly 10. For this, the aerosol-generating device 60 comprises a receiving cavity 62 formed within the device housing 61 in a proximal portion of the device 60. The receiving cavity 62 is configured to removably receive at least a portion of the aerosol-generating article 40. For heating the susceptor assembly 10, the aerosol-generating device 60 comprises an induction source including an induction coil 4. In the present embodiment, the induction coil 4 is a single helical coil which is arranged and configured to generate a substantially homogeneous alternating magnetic field. As can be seen in FIG. 1, the induction coil 4 is arranged around the proximal end portion of the receiving cavity 62 such as to surround a portion of the non-grid portion of the susceptor assembly 10, when the aerosol-generating article 40 is received in the receiving cavity 62. In particular, the induction coil 4 is arranged such as to generate an alternating magnetic field that locally penetrates the susceptor assembly, in particular the non-grid portion only in the heating section 17. In contrast, due to the local heating, the soaking section 16 of the filament bundle 18 stays at temperatures below the vaporization temperature. Thus, boiling of aerosol-forming liquid 51 within the liquid reservoir 41 is prevented.

[0207] Together, the induction source of the aerosol-generating device 60 and the susceptor assembly 10 of the aerosol-generating article 44 form an inductive heating assembly according to the present invention.

[0208] The aerosol-generating device 60 further comprises a controller 64 for controlling operation of the aerosol-generating system 80, in particular for controlling the heating operation.

[0209] Furthermore, the aerosol-generating device 60 comprises a power supply 63 providing electrical power for generating the alternating magnetic field. Preferably, the power supply 63 is a battery such as a lithium iron phosphate battery. The power supply 63 may have a capacity that allows for the storage of enough energy for one or more user experiences.

[0210] Both, the controller 64 and the power supply 63 arranged in a distal portion of the aerosol-generating device 60.

[0211] For the purpose of the present description and of the appended claims, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term “about”. Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein. In this context, therefore, a number A is understood as A±5 percent of A. Within this context, a number A may be considered to include numerical values that are within general standard error for the measurement of the property that the number A modifies. The number A, in some instances as used in the appended claims, may deviate by the percentages enumerated above provided that the amount by which A deviates does not materially affect the basic and novel characteristic(s) of the claimed invention. Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein.