WO2024003365A1

WO2024003365A1 - Aerosol generating assembly comprising a heat conducting element

Info

Publication number: WO2024003365A1
Application number: PCT/EP2023/068033
Authority: WO
Inventors: Jaakko MCEVOY; Alec WRIGHT
Original assignee: Jt International Sa
Priority date: 2022-07-01
Filing date: 2023-06-30
Publication date: 2024-01-04

Abstract

The present invention concerns an aerosol generating assembly comprising a cavity (52) extending along a device axis (Z) and configured to receive an aerosol generating article. The assembly (10) comprises: - a heat conducting element configured to heat a tobacco portion (15) of the aerosol generating article; and - a heater (62) configured to generate heat and transfer it to the heat conducting element; wherein the heat conducting element comprises a first longitudinal part (74A) arranged to form or to face at least partially a wall delimiting the cavity (52) along the device axis (Z); wherein the heater (62) is fixed transversally at a closed end of the cavity (52) or longitudinally substantially at the center of the first longitudinal part (74A) of the heat conducting element.

Description

Aerosol generating assembly comprising a heat conducting element

FIELD OF THE INVENTION

The present invention concerns an aerosol generating assembly comprising a heat conducting element. According to one embodiment of the invention, the aerosol generating assembly corresponds to an aerosol generating device configured to operate with an aerosol generating article. According to another embodiment, the aerosol generating assembly comprises an aerosol generating device and an aerosol generating article configured to operate with such a device.

The aerosol generating article in the meaning of the invention comprises for example a solid substrate able to form aerosol when being heated. Thus, the aerosol generating device configured to operate with such an article, also known as a heat-not-burn device, is adapted to heat, rather than burn to generate aerosol for inhalation.

BACKGROUND OF THE INVENTION

The popularity and use of reduced-risk or modified-risk devices (also known as vaporisers) has grown rapidly in the past few years. Various devices and systems are available that heat or warm vaporizable substances as opposed to burning tobacco in conventional tobacco products.

A commonly available reduced-risk or modified-risk device is the heated substrate aerosol generation device or heat-not-burn device. Devices of this type generate aerosol or vapour by heating an aerosol substrate that typically comprises moist leaf tobacco or other suitable vaporizable material to a temperature typically in the range 150°C to 350°C. Heating an aerosol substrate, but not combusting or burning it, releases aerosol that comprises the components sought by the user but almost not by-products of combustion and burning. Furthermore, the aerosol produced by heating the tobacco or other vaporizable material does not typically comprise the taste resulting from combustion and burning that can be bit unpleasant for the user and so the substrate does not therefore require the sugars and other additives that are typically added to such materials to make the smoke and/or vapour more palatable for the user. To ensure the heating of the aerosol generating substrate, known aerosol generating devices comprise generally a heater made for example of ceramics. Ceramic heaters are commonly used in the devices due to their low cost, durability, high temperature application and many available form factors. However, a large downside of ceramic heaters is the thermal inertia that they carry, which results in increased time and energy to reach the desired temperature. Additionally, since this energy consumption is linked directly to the mass and therefore the volume, and since the volume of the device scales cubically, any small change in length, width, depth, etc. of the heater results in significant reductions in heat up energy.

Thus, usage of existing ceramic heaters leads to a large energy consumption and consequently to large requirements for batteries. Additionally, any variation of the shape or a dimension of a ceramic heater leads to large variations of its heating up capacity and heating efficiency.

SUMMARY OF THE INVENTION

One of the aims of the invention is to provide an aerosol generating assembly providing a decreased energy consumption and being less sensible to different variations of the heater’s shape and/or dimensions.

For this purpose, the invention relates to an aerosol generating assembly comprising a cavity extending along a device axis between a closed end and an open end, and configured to receive an aerosol generating article the aerosol generating article extending along an article axis and comprising a tobacco portion and a mouthpiece portion arranged successively along the article axis; the assembly comprising:

- a heat conducting element configured to heat the tobacco portion of the aerosol generating article; and

- a heater configured to generate heat and transfer it to the heat conducting element; wherein the heat conducting element comprises a first longitudinal part arranged to form or to face at least partially a wall delimiting the cavity along the device axis; wherein the heater is fixed transversally at the closed end of the cavity or longitudinally substantially at the center of the first longitudinal part of the heat conducting element. Thanks to these features, the heater in the aerosol generating assembly according to the invention may be provided with smaller dimensions in comparison with heaters conventionally used in similar type of aerosol generating assemblies. This reduces its power consumption and battery requirements while keeping a good heating efficiency. Particularly, according to the present invention, the heat conducting element is adapted to ensure a good heating efficiency of the tobacco portion by heat transfer from the heater. Thus, the heater can present reduced dimensions and different variations of its shape and/or dimensions have less influence on the global heating efficiency of the assembly. It is clear for a person skilled in the art that the heater may present any convenient shape/dimensions and not only the shape/dimensions corresponding to those of the tobacco article, as it is done conventionally in the art.

When the heater is fixed at the center of the first longitudinal part of the heat conducting element, it is understood that its center according to its longitudinal dimension coincides substantially with the center of the first longitudinal part of the heat conducting element according to the same longitudinal dimension. By “substantially coincide”, it is understood that the centers can be in offset according to the corresponding longitudinal dimension which is less than 30%, advantageously 20% and preferably 10% and even more preferably 5%, than the longitudinal dimension of the first longitudinal part of the heat conducting element. A similar definition can be used in relation with the center of a second longitudinal part, when it is applicable.

When the heater is fixed transversally at the closed end of the cavity, it can be fixed substantially perpendicularly to the first longitudinal part of the heat conducting element. In this case, the first longitudinal part may be free of direct contact with a heater or may be in contact with another heater, which may be fixed to the first longitudinal part at any position in respect with this part, as it will be explained in further detail below.

At either arrangement of the heater in respect with the first longitudinal part, the heat conducting element may form at least partially a wall delimiting the cavity of the device receiving the aerosol generating article. In other words, in this case, the heat conducting element is integrated into the aerosol generating device. According to another embodiment, the heat conducting element only faces a wall delimiting the cavity of the device receiving the aerosol generating article. In this case, it means that the heat conducting element is integrated into the aerosol generating article. According to some embodiments, the heater comprises a heating surface arranged adjacent to the heat conducting element.

Thanks to these features, the heater can be in direct contact with the heat conducting element that improves considerably heat transfer from the heater to the heat conducting element.

According to some embodiments, wherein the heating surface presents a longitudinal dimension, the ratio between the length of the first longitudinal part of the heat conducting element and said longitudinal dimension of the heating surface being greater than 2, advantageously greater than 3 and preferably greater than 4.

Thanks to these features, the dimensions of the heater can be significantly reduced while ensuring a good heating efficiency of the assembly. Additionally, as mentioned above, the heating surface of the heater can have any convenient shape, as for example a rectangular, an oval, a circular, a star or any other regular or irregular shape. The shape of the heating surface can for example be adapted to optimize heat transfer from the heater to the heat conducting element.

According to some embodiments, the first longitudinal part is the only longitudinal part of the heat conducting element.

In other words, in this case, the heat conducting element extends only along one side of the aerosol generating article so as only one side of the tobacco portion can be heated. This is for example particularly suitable for a flat-shaped aerosol generating article. In this case, the heater can be arranged according to one of the embodiments explained above, i.e. transversally at the closed end of the cavity or longitudinally substantially at the center of the first longitudinal part of the heat conducting element. The non-heated side of the tobacco portion can be covered by a thermal insulator to minimize heat losses. According to this embodiment, the aerosol generating device can have a particularly thin shape.

According to some embodiments, the heat conducting element further comprises a second longitudinal part arranged facing the first longitudinal par.

Thanks to these features, both longitudinal parts of the heat conducting element are used to heat the tobacco portion of the aerosol forming article. Thus, the tobacco portion can be heated more evenly that improves the quality of the aerosol generated by the assembly. Additionally, this configuration of the heat conducting element is particularly advantageous in case of a flat-shaped tobacco article having wide walls at least several times (for example at least 5 times or 10 times) wider than its narrow walls. In this case, the first and the second longitudinal parts of the heat conducting element may at least partially form or face the wide walls of the aerosol generating article.

According to some embodiments, the heat conducting element further comprises a transversal part arranged to form a transversal wall of the cavity and connecting the first and the second longitudinal parts.

Thanks to these features, the first and the second longitudinal parts can be connected between them. This ensures heat transfer between these parts. In addition, this transversal part also heats the tobacco portion of the aerosol forming article as same as the first and the second longitudinal parts. It may lead the improvement of heating efficiency.

According to some embodiments, the heater is the unique heater of the assembly and is arranged adjacent to the transversal part of the heat conducting element.

Thanks to these features, the first and the second longitudinal parts of the heat conducting element may heat the tobacco portion by heat transfer from the transversal part. In this case, the aerosol generating device may present particularly compact dimensions (regarding for example its thickness) since the only heater is arranged at the closed end of the cavity. Additionally, since no heater is provided on a side of the aerosol generating device, less insulation is required on this side. This can make the device even thinner.

According to some embodiments, comprising at least two different heaters arranged adjacent to different parts of the heat conducting element.

Thanks to these features, the tobacco portion can be heated more evenly using at least two heaters arranged adjacent to different parts of the heat conducting element. For example, the device can comprise three heaters arranged adjacent to the transversal part of the heat conducting element and each of the longitudinal parts.

According to some embodiments, comprising only two different heaters arranged adjacent to the first and the second longitudinal parts of the heat conducting element. Thanks to these features, the tobacco portion can be heated from its opposite sides. Thus, an even heating inside the tobacco portion can be achieved. Additionally, this configuration of the heaters is particularly advantageous in case of a flat-shaped tobacco article having wide walls at least several times (for example at least 5 times or 10 times) wider than its narrow walls. In this case, the heaters may be arranged to face the opposite wide walls of the aerosol generating article that makes particularly efficient the heating of the tobacco portion.

According to some embodiments, the length of the or each longitudinal part of the heat conducting element is equal or greater to/than the length of the tobacco portion of the aerosol generating article.

According to some embodiments, ,when the aerosol generating article is received in the cavity, the or each longitudinal part of the heat conducting element covers entirely the tobacco portion.

Thanks to these features, the tobacco portion of the aerosol generating article can be covered entirely by at least one longitudinal part of the heat conducting element. It is thus possible to optimize heat transfer from the heat conducting element to the tobacco portion and ensure even heating of this tobacco portion.

Additionally, when the length of the or each longitudinal part of the heat conducting element is greater than the length of the tobacco portion of the aerosol generating device, the tobacco portion can be covered entirely even if the user has insufficiently inserted the aerosol generating article into the cavity. Since the tobacco portion is not rigid object, the complete insertion is not easy for some users. Thus, such configuration may improve usability for these users. In this case, the or each longitudinal part can be several millimeters (for example 1 , 2 or 3 mm) longer than the tobacco portion.

According to some embodiments, the length of the or each longitudinal part of the heat conducting element is less than the length of the tobacco portion of the aerosol generating article.

According to some embodiments, when the aerosol generating article is received in the cavity, an uncovered part of the tobacco portion is formed at the open end of the cavity. Thanks to these features, it is possible to suppress excess aerosol generated during a vaping session. In this case, the or each longitudinal part can be several millimeters (for example 1 , 2 or 3 mm) shorter than the tobacco portion. In a general case, the difference between said lengths may be adapted to ensure an optimized aerosol generation during a vaping session. This difference can for example be determined empirically.

According to some embodiments, the heater defines a center and forms a shape symmetric in respect to the center; preferably the heater forms a circular or a donut shape.

Thanks to these features, it is possible to avoid over-heating in the center part of the heater. Additionally, in such a configuration, the heat can be spread more evenly along the heat conducting element. Moreover, in some embodiments, the center of the heater can coincide with the center of the heat conducting element. For example, the heater’s arrangement and shape can be adapted so as each point of the heat conducting element is substantially equally distanced from the heater. In this case, heaters having a symmetric shape in respect to the center, like for example a circular, square or donut shape, can be particularly advantageous since the heat can be spread more evenly along the heat conducting element.

According to some embodiments, the heat conducting element is made from graphene or aluminum.

Thanks to these features, it is possible to achieve a very fast heat transmission along the heat conducting element. For example, the thermal conductivity of aluminum may achieve 204 W/m.K and of graphene 1 800 W/m.K. This offers almost instantaneous heating of the heat conducting element. Thus, the heat up phase of the aerosol generating article can be shortened.

According to some embodiments, at least a part of the heat conducting element is integrated into an aerosol generating device configured to operate with the aerosol generating article.

Thanks to these features, it is possible to attach firmly the heater to the heat conducting element so as to ensure their contact. Thus, heat transfer between these elements can be optimized. Additionally, in this case, it is not necessary to provide a heat conducting element/material in the aerosol generating article. The cost of such an article can consequently be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention and its advantages will be better understood upon reading the following description, which is given solely by way of non-limiting example and which is made with reference to the appended drawings, in which:

- Figure 1 is a schematic view of an aerosol generating assembly according to a first embodiment of the invention, the aerosol generating assembly corresponding to an aerosol generating device configured to operate with an aerosol generating article;

- Figure 2 is a perspective view of the aerosol generating article of Figure 1 ;

- Figure 3 shows schematic views of different examples of arrangement of a heater in respect with a heat conducting element inside the aerosol generating device of Figure 1 ;

- Figure 4 shows schematic views of different examples of arrangement of the heat conducting element in respect with the aerosol generating article of Figure 1 ;

- Figure 5 is a schematic view of an aerosol generating assembly according to a second embodiment of the invention, the aerosol generating assembly comprising an aerosol generating device (shown separately in the top part of the figure) and an aerosol generating article (shown received in the aerosol generating device in the bottom part of the figure); and

- Figure 6 is a side view of the aerosol generating article of Figure 5.

DETAILED DESCRIPTION OF THE INVENTION

Before describing the invention, it is to be understood that it is not limited to the details of construction set forth in the following description. It will be apparent to those skilled in the art having the benefit of the present disclosure that the invention is capable of other embodiments and of being practiced or being carried out in various ways. As used herein, the term “aerosol generating device” or “device” may include a vaping device to deliver an aerosol to a user, including an aerosol for vaping, by means of a heater element explained in further detail below. The device may be portable. “Portable” may refer to the device being for use when held by a user. The device may be adapted to generate a variable amount of aerosol, e.g. by activating the heater element for a variable amount of time (as opposed to a metered dose of aerosol), which can be controlled by a trigger. The trigger may be user activated, such as a vaping button and/or inhalation sensor. The inhalation sensor may be sensitive to the strength of inhalation as well as the duration of inhalation to enable a variable amount of vapour to be provided (so as to mimic the effect of smoking a conventional combustible smoking article such as a cigarette, cigar or pipe, etc.). The device may include a temperature regulation control to drive the temperature of the heated aerosol generating substance (aerosol pre-cursor) to a specified target temperature and thereafter to maintain the temperature at the target temperature that enables efficient generation of aerosol.

As used herein, the term “aerosol” may include a suspension of vaporizable material as one or more of: solid particles; liquid droplets; gas. Said suspension may be in a gas including air. Aerosol herein may generally refer to/include a vapour. Aerosol may include one or more components of the vaporizable material.

As used herein, the term “vaporizable material” or “precursor” may refer to a smokable material which may for example comprise nicotine or tobacco and an aerosol former. Tobacco may take the form of various materials such as shredded tobacco, granulated tobacco, tobacco leaf and/or reconstituted tobacco. Suitable aerosol formers include: a polyol such as sorbitol, glycerol, and glycols like propylene glycol or triethylene glycol; a non-polyol such as monohydric alcohols, acids such as lactic acid, glycerol derivatives, esters such as triacetin, triethylene glycol diacetate, triethyl citrate, glycerin or vegetable glycerin. In some embodiments, the aerosol generating agent may be glycerol, propylene glycol, or a mixture of glycerol and propylene glycol. The substrate may also comprise at least one of a gelling agent, a binding agent, a stabilizing agent, and a humectant.

By term “longitudinal dimension” or “length” of an element, it is understood the length of this element according to the device axis when the aerosol generating device is assembled together with the aerosol generating article. FIRST EMBODIMENT OF THE INVENTION

Figure 1 shows an aerosol generating assembly 10 according to the first embodiment of the invention. According to this embodiment, the assembly 10 corresponds to an aerosol generating device 1 1 adapted to operate with an aerosol generating article 12, also called tobacco article 12, which is shown in more detail in Figure 2.

The aerosol generating article 12 extends along an article axis X and a transversal direction Y perpendicular to the article axis X. In the example of Figure 2, the aerosol generating article 12 has a flat shape and its transversal direction Y presents a rectilinear axis which is perpendicular to the article axis X and forms with this article axis X an extension plane of the aerosol generating article 12. By “flat shape” of such an aerosol generating article it is understood that its depth (i.e. dimension extending perpendicularly to the extension plane) is several times less (for example at least 5 times or at least 10 times) than its any other dimension measured in the extension plane (as for example length or width).

According to other embodiments, the aerosol generating article 12 presents any other suitable shape, as for example a cylindrical shape having a substantially circular crosssection. In this last case, the transversal direction Y is understood as a circumferential direction extending around the article axis X.

In reference to Figure 2, the aerosol generating article 12 presents a cuboid extending along the article axis X and having external dimensions LxWxD. In a typical example, the length L of the article 12 according to the article axis X is around 30 mm while its width W and depth D are substantially is respectively around 10 mm and around 1 ,0 mm. According to different examples, the values L, W and D can be selected within a range of +/- 40%, for example. The depth D of the tobacco article 12 is formed by a pair of parallel walls 13A, 13B, called hereinafter narrow walls 13A, 13B, and the width W of the substrate is formed by a pair of parallel walls 14A, 14B, called hereinafter wide walls 14A, 14B. In some embodiments, the edges between the wide and narrow walls 13A, 13B, 14A, 14B can be rounded.

The aerosol generating article 12 comprises a tobacco portion 15 and a mouthpiece portion 16 arranged successively along the article axis X. The tobacco portion 15 may for example be longer than the mouthpiece portion 16. For example, the length L2 of the tobacco portion 15 according to the article axis X may be around 25 mm and the length L1 of the mouthpiece portion 16 according to the article axis X may be around 8 mm. These dimensions are given only as examples and can vary considerably depending on different examples of the invention. The tobacco portion 15 defines a tobacco end 18 of the article 12 and the mouthpiece portion 16 defines a mouth end 20 of the article 12. The tobacco portion 15 and the mouthpiece portion 16 may be fixed one to the other by a wrapper 21 extending around the substrate axis X. The wrapper 21 forms the narrow and wide walls 13A, 13B, 14A, 14B of the tobacco article 12. In some embodiments, the wrapper 21 is formed from a same wrapping sheet. In some other embodiments, the wrapper 21 is formed by separate wrapping sheets wrapping separately the portions 15, 16 and fixed one to the other by any other suitable mean. The wrapper 21 may, for example, comprise paper and/or non-woven fabric and/or aluminium foil. The wrapper 21 may be porous or air impermeable and forms a plurality of airflow channels extending inside the article 12 between the tobacco end 18 and the mouth end 20. Advantageously, the wrapper 21 does not cover transversal faces 25, 26 of the tobacco article 12 extending perpendicularly to the article axis X and formed respectfully by the tobacco portion 15 at the tobacco end 18 and the mouthpiece portion 16 at the mouth end 20.

The mouthpiece portion 16 comprises a core 27 intended to act for example as a cooler and/or filter to cool and/or filter slightly the vapour before it is inhaled by the user and may comprise for this purpose for example corrugated paper. The core 27 may be formed through an extrusion and/or rolling process into a stable shape. Advantageously, the core 27 is arranged inside the mouthpiece portion 16 to be entirely in contact with the internal surface of the wrapper 21 delimiting this mouthpiece portion 16. In other words, no gap is formed in the mouthpiece portion 16 between the internal surface of the wrapper 21 and the core 27. The core 27 also may secure the mechanical strength of the aerosol generating article 12.

In a particular embodiment of the invention (not shown), the mouthpiece portion 16 defines a plurality of venting holes arranged for example according to the whole perimeter of the mouthpiece portion 16 along two axis perpendicular to the article axis X. In other words, according to this particular embodiment, the venting holes are arranged on each wall of the substrate among the narrow walls 13A, 13B and the wide walls 14A, 14B. According to another example, the venting holes are arranged only on the wide walls 14A, 14B or preferably, only on one of the wide walls 14A, 14B. In both examples, the venting holes may be aligned perpendicularly to the article axis X on the or each corresponding wall of the article 12, and can be spaced by a same distance. The venting holes allow fresh air entering inside the article 12 to achieve particular vaping/tasting effects. In a preferred embodiment of the invention, no venting hole is provided.

The tobacco portion 15 comprises a vaporizable material as defined above. Notably, the tobacco portion 15 comprises shredded tobacco and/or tobacco particles.

In a possible embodiment, the tobacco portion 15 is formed of pressed layer of aerosol material comprising tobacco particles and/or inhalable agent, which contains at least one of stimulant and/or flavor, a gelling agent for gelling the material and a degradation preventing and/or thickening stabilizer and an aerosol forming agent such as described in WO 2021094365. The gelling agent may be a non-protein containing polysaccharide and/or comprise gellan gum, lecithin, agar or mixtures thereof. The aerosol former may be comprised between 20 and 70 wt. % of the total weight of the vaporizable material. The aerosol forming agent may be glycerol, propylene glycol, ethanol, water or a combinations thereof. The degradation preventing and/or thickening stabilizer may be carboxymethylcellulose and/or hydroxy alkylated carbohydrates. Preferably, it is purified CMC such as Ceroga 4550 C or CEOKOL 2000 (C.E. Roeper GmBH).

Referring again to Figure 1 , the aerosol generating device 1 1 comprises a device body 50 defining a cavity 52 extending along a device axis Z between a closed end 53A and open end 53B and configured to receive at least partially the tobacco article 12 through its open end 53A. Particularly, the cavity 52 forms a complementary shape to the shape of the tobacco article 12. Additionally, in case of a flat-shaped tobacco article, the cavity 52 is configured to receive the tobacco article 12 according to two different ways in which the article axis X coincides with the device axis Z and the mouthpiece portion 16 protrudes from the cavity 52 or is arranged in the cavity’s opening. The two different ways of insertion of the tobacco article 12 are obtained one from the other by rotation the tobacco article 12 around the article axis X by 180°.

The device body 50 delimits an internal space of the device 11 receiving various elements designed to carry out different functionalities of the device 1 1 . This internal space can for example receive a battery 54 for powering the device 1 1 , a controller 56 for controlling the operation of the device 11 , a heating system 58 for heating the tobacco portion 15 of the aerosol generating article 12, etc. The controller can mainly comprise at least one of a micro controller unit or micro processing unit. Among these elements, only the heating system 58 will be explained in further detail in reference to Figures 3 and 4. According to the first embodiment of the invention, the heating system 58 is comprised entirely in the aerosol generating device 11 .

The heating system 58 comprises a heat conducting element configured to heat the tobacco portion 15 of the aerosol generating article 12 and at least one heater 62 configured to generate heat and transfer it to the heat conducting element. The or each heater 62 presents for example a resistive element configured to be powered by the battery 54 and controlled by the controller 56. The or each heater 62 forms for example a circular or a donut shape, and defines a heating surface arranged adjacent to the heat conducting element. The heat conducting element is made of or comprises heat conductive material such as graphene or aluminum.

Different examples of respective arrangement of the or each heater 62 and the heat conducting element are shown in Figure 3.

Particularly, in example A of Figure 3, the heat conducting element comprises a first longitudinal part 74A and a second longitudinal part 74B arranged facing the first longitudinal part 74A and for example disconnected from this first longitudinal part 74A. Each of the longitudinal parts 74A, 74B extends along the device axis Z and forms at least partially a side wall of the cavity 52. Each of the longitudinal parts 74A, 74B can be formed by a plate. Particularly, each of the longitudinal parts 74A, 74B comprises a contact surface which is designed to be in contact with the corresponding wide wall 14A, 14B of the aerosol generating article 12 when it is inserted into the cavity 52. Depending on the insertion way of the aerosol generating article 12, the first longitudinal part 74A can be in contact with the wide wall 14A or the wide wall 14B. Respectively, the second longitudinal part 74B can be in contact with the wide wall 14B or the wide wall 14A. In example A of Figure 3, a heater 62 is arranged at the center of each longitudinal part 74A, 74B of the heat conducting element. Particularly, in this example, the heating system 58 comprises two heaters 62, for example substantially similar between them. Each heater 62 presents a heating surface extending along the device axis Z and attached to the surface of the corresponding longitudinal part 74A, 74B opposite to the contact surface of this part. Advantageously, the ratio between the length of the each longitudinal part 74A, 74B of the heat conducting element and the longitudinal dimension of the corresponding heating surface is greater than 2, advantageously greater than 3 and preferably greater than 4. In example B of Figure 3, the heat conducting element further comprises a transversal part 74C arranged perpendicularly to each longitudinal part 74A, 74B and connecting the longitudinal parts 74A, 74B between them. The parts 74A to 74C may form one single piece. Alternatively, the parts 74A to 74C may form separated pieces. The transversal part 74C forms thus a wall of the cavity 52 at its closed end 53A. The transversal part 74C defines a contact surface which is designed to be at least partially in contact with the transversal face 25 of the aerosol generating article 12. In this example, the heating system 58 comprises three heaters 62. A first and a second heaters 62 are arranged adjacent respectfully to the first and the second longitudinal parts 74A, 74B of the heat conducting element. Each of the first and the second heaters 62 is similar to the heater 62 explained in relation with example A. Particularly, in example B, each of the first and the second heaters 62 is arranged at the center of the corresponding longitudinal part 74A, 74B of the heat conducting element. According to another embodiment (not-shown), at least one of these heaters 62 is arranged at the end of the corresponding longitudinal part 74A, 74B, adjacent to the closed end 53A or the open end 53B of the cavity 52. A third heater 62 presents a heating surface which extends transversally to the device axis Z. As shown in example B of Figure 3, this third heater 62 is arranged adjacent to a surface of the transversal part 74C of the heat conducting element, opposite to the contact surface of this part 74C. The third heater 62 may be similar to each of the first and the second heaters 62.

In example C of Figure 3, the heat conducting element is similar to one explained in relation with example B. Particularly, as in the previous example, the heat conducting element comprises two longitudinal parts 74A, 74B and a transversal part 74C connecting transversally the longitudinal parts 74A, 74B. Contrary to example B, only one heater 62 is provided in example C. This heater 62 is for example similar to the third heater 62 explained in relation with the previous example and is arranged similarly to this third heater 62. In a variant, the heater 62 of example C may present a greater heating surface and/or heating capacity than the third heater 62 explained in relation with example C.

Figure 4 shows different examples of arrangement of the heat conducting element in respect with the tobacco portion 15. In these examples, similarly to example A of Figure 3, the heat conducting element comprises a first and a second longitudinal parts 74A, 74B which are arranged in a similar way with the corresponding heater 62 as explained in relation with this example A of Figure 3. A person skilled in the art would however understand that different examples of arrangement of the heat conducting element in respect with the tobacco portion 15 as explained below, remain applicable to examples B to C of Figure 3 as well as to other possible respective arrangements of the heat conducting element in respect with the or each heater 62 according to the invention.

Particularly, in example A of Figure 4, each of the longitudinal parts 74A, 74B has substantially the same length as the tobacco portion 15 when the aerosol generating article 12 is inserted into the cavity 52 so as the transversal face 25 of the article 12 abuts or is at least partially in contact with a wall of the cavity 52 delimiting its closed end 53A. Thus, in this example, the tobacco portion 15 is entirely covered by the heat conducting element.

In example B of Figure 4, each of the longitudinal parts 74A, 74B is shorter than the tobacco portion 15 when the aerosol generating article 12 abuts or is at least partially in contact with a wall of the cavity 52 delimiting its closed end 53A. The difference between these lengths may for example be adapted to supress the excess of aerosol generated during a vaping session.

In examples C and D, each of the longitudinal parts 74A, 74B is longer than the tobacco portion 15. In example C, the aerosol generating article 12 abuts or is at least partially in contact with a wall of the cavity 52 delimiting its closed end 53A. Thus, in this case, each of the longitudinal parts 74A, 74B extends over the tobacco portion 15 at the open end 53B of the cavity 52. In example D, the aerosol generating article 12 forms a gap with the wall of the cavity 52 delimiting its closed end 53A and at the open end 53 B of the cavity 52, the end of each of the longitudinal parts 74A, 74B is aligned with the end of the tobacco portion 15. Example D shows thus that the tobacco portion 15 can be entirely covered by the heat conducting element even if the aerosol generating article 12 is inserted insufficiently into the cavity 52.

SECOND EMBODIMENT OF THE INVENTION

An aerosol generating assembly 100 according to the second embodiment of the invention comprises an aerosol generating device 1 11 and an aerosol generating article 112.

The aerosol generating device 1 11 according to the second embodiment is similar to the aerosol generating device 11 according to the first embodiment. The similar elements of these devices 1 1 , 11 1 are not explained in further detail below. The only difference of the aerosol generating device 1 11 of the second embodiment is a heating system 158 which, according to the second embodiment, is distributed between the aerosol generating device 11 1 and the aerosol generating article 1 12.

Particularly, as in the previous case, the heating system 158 comprises one or several heaters 162 which can be arranged in respect with the cavity similarly to one of the examples of Figure 3. In the example of Figure 5, a heater 162 extends transversally to the device axis Z and forms at least partially a wall of the cavity 52 at its closed end 53A. The heater 162 is for example similar to one of the heaters 62 explained in relation with examples B or C of Figure 3.

The heating system 158 also comprises a heat conducting element which is, contrary to the previous case, integrated into the aerosol generating article 112. Particularly, in the example of Figure 6 showing the aerosol generating article 1 12 according to the second embodiment, the heat conducting element comprises two opposite longitudinal parts 174A, 174B extending along the article axis X and forming at least partially the wide walls 14A, 14B of the article 112. Each of the opposite longitudinal parts 174A, 174B is intended to be in contact with at least one heater 162 when the aerosol generating article 1 12 is received in the cavity 52. For this purpose, a heater 162 can for example be arranged on a side wall of the cavity 52. According to the example of Figures 5 and 6, each of the opposite longitudinal parts 174A, 174B is intended to be in contact with the same heater 162 arranged at the closed end 53A of the cavity 52. For this purpose, the aerosol generating article 112 defines a recess portion 180 at its tobacco end 18 configured to receive the heater 162 upon insertion of the aerosol generating article 1 12 into the cavity 52. In this position, the heater 162 defines two opposite heating surfaces extending longitudinally and is sandwiched between the longitudinal parts 174A, 174B so as these heating surfaces remain in contact with the longitudinal parts 174A, 174B. The longitudinal parts 174A, 174B are made of or comprise a heat conductive material such as aluminium or graphene. The longitudinal parts 174A, 174B can be a part of the wrapper 21 explained in detail in relation with the previous embodiment or can overwrap this wrapper 21. Advantageously, the longitudinal parts 174A, 174B cover only the tobacco portion 15 of the article 112. The tobacco portion 15 can be thus covered either entirely or partially. Additionally, in some embodiments, the longitudinal parts 174A, 174B may form at least partially the narrow walls 13A, 13B of the article 12. In this case, the longitudinal parts 174A, 174B can be formed by a unique sheet wrapping the tobacco portion 15. The other features of the aerosol generating article 112 remain unchanged in comparison with the aerosol generating article 12 explained in relation with the first embodiment.

Claims

1 . An aerosol generating assembly (10; 1 10) comprising a cavity (52) extending along a device axis (Z) between a closed end (53A) and an open end (53B), and configured to receive an aerosol generating article (12; 1 12), the aerosol generating article (12; 1 12) extending along an article axis (X) and comprising a tobacco portion (15) and a mouthpiece portion (16) arranged successively along the article axis (X); the assembly (10; 110) comprising:

- a heat conducting element configured to heat the tobacco portion (15) of the aerosol generating article (12; 1 12); and

- a heater (62; 162) configured to generate heat and transfer it to the heat conducting element; wherein the heat conducting element comprises a first longitudinal part (74A; 174A) arranged to form or to face at least partially a wall delimiting the cavity (52) along the device axis (Z); wherein the heater (62; 162) is fixed transversally at the closed end (53A) of the cavity (52).

2. The aerosol generating assembly (10; 110) according to claim 1 , wherein the heater (62; 162) comprises a heating surface arranged adjacent to the heat conducting element.

3. The aerosol generating assembly (10; 1 10) according to claim 1 or 2, wherein the first longitudinal part (74A; 174A) is the only longitudinal part of the heat conducting element.

4. The aerosol generating assembly (10; 110) according to claim 1 or 2, wherein the heat conducting element further comprises a second longitudinal part (74B; 174B) arranged facing the first longitudinal part (74A; 174A).

5. The aerosol generating assembly (10; 110) according to claim 4, wherein the heat conducting element further comprises a transversal part (74C) arranged to form a transversal wall of the cavity (52) and connecting the first and the second longitudinal parts (74A, 74B; 174A, 174B); preferably the heater (62; 162) being adjacent to the transversal part (74C).

6. The aerosol generating assembly (10; 110) according to claim 5, wherein the heater (62; 162) is the unique heater of the assembly (10; 1 10) and is arranged adjacent to the transversal part (74C) of the heat conducting element.

7. The aerosol generating assembly (10; 110) according to any one of claims 4 or 5, comprising at least two different heaters (62; 162) arranged adjacent to different parts (74A, 74B, 74C; 174A, 174B, 174C) of the heat conducting element.

8. The aerosol generating assembly (10; 110) according to any one of claim 7, wherein one of said two heaters is fixed longitudinally substantially at the center of the first longitudinal part (74A; 174A) of the heat conducting element.

9. The aerosol generating assembly (10; 110) according to any one of the preceding claims, wherein the length of the or each longitudinal part of the heat conducting element is equal or greater to/than the length of the tobacco portion (15) of the aerosol generating article (12; 1 12) when it is received in the cavity (52).

10. The aerosol generating assembly (10; 1 10) according to claim 9, wherein, when the aerosol generating article (12; 112) is received in the cavity (52), the or each longitudinal part of the heat conducting element covers entirely the tobacco portion.

11 . The aerosol generating assembly (10; 1 10) according to any one of claims 1 to 8, wherein the length of the or each longitudinal part of the heat conducting element is less than the length of the tobacco portion (15) of the aerosol generating article (12; 1 12) when it is received in the cavity (52).

12. The aerosol generating assembly (10; 1 10) according to claim 1 1 , wherein, when the aerosol generating article (12; 112) is received in the cavity, an uncovered part of the tobacco portion (15) is formed at the open end (53B) of the cavity (52).

13. The aerosol generating assembly (10; 110) according to any one of the preceding claims, wherein the heater (62; 162) defines a center and forms a shape symmetric in respect to the center; preferably the heater (62; 162) forms a circular or a donut shape.

14. The aerosol generating assembly (10; 110) according to any one of the preceding claims, wherein the heat conducting element is made from graphene or aluminum.

15. The aerosol generating assembly (10) according to any one of the preceding claims, wherein at least a part of the heat conducting element is integrated into an aerosol generating device (1 1 ) configured to operate with the aerosol generating article (12; 1 12).