EP3944777A1

EP3944777A1 - Heating system by susceptor filings for an aerosol generation assembly and associated cartridge, aerosol generation device and aerosol generation assembly

Info

Publication number: EP3944777A1
Application number: EP20188713.0A
Authority: EP
Inventors: Ola POPOOLA; Alec WRIGHT; Andrew ROGAN; Kyle ADAIR; Peter LOVEDAY
Original assignee: JT International SA
Current assignee: JT International SA
Priority date: 2020-07-30
Filing date: 2020-07-30
Publication date: 2022-02-02

Abstract

A heating system 34 for an aerosol generation assembly 10 including an aerosol generation device 12 and a cartridge 14 comprises: a heating circuit comprising an AC source 80 connected to a battery of the device 12, a coil 82 intended to be arranged around a storage portion 66 of the device 12 along the cartridge axis and connected to the AC source 80, and susceptor filings 84 arranged or able to be arranged in the storage portion 66 along the cartridge axis; a control module configured to control the operation of the heating circuit to generate heat into the storage portion 66 by currents induced in the susceptor filings (84) by the coil (82). A measuring circuit to generate measurements relative to the precusor level in the storage portion comprises a pair of capacitor electrodes 91, 92.

Description

FIELD OF THE INVENTION

The present invention concerns a heating system by susceptor filings for an aerosol generation assembly.
The present invention also concerns an associated cartridge, an aerosol generation device designed to operate with such a cartridge and an aerosol generation assembly comprising such a cartridge and such an aerosol generation device.

BACKGROUND OF THE INVENTION

Different types of aerosol generation devices are already known in the art. Generally, such devices comprise a storage portion for storing an aerosol forming precursor, which can comprise for example a liquid or a solid. A heating system is formed of one or more electrically activated resistive heating elements arranged to heat said precursor to generate the aerosol. The aerosol is released into a flow path extending between an inlet and outlet of the device. The outlet may be arranged as a mouthpiece, through which a user inhales for delivery of the aerosol.
In some aerosol generation devices, the precursor is stored in a removable cartridge. Thus, when the precursor is consumed, the cartridge can be easily removed and replaced. In order to attach the removable cartridge to the device body, a screw-threaded connection can for example be used.
In some known aerosol generation devices using removable cartridges, the heating system is distributed between the aerosol generation device and the cartridge. In this case, the part of the heating system comprised in the aerosol generation device may be formed for example by a pair of contacts connected electrically to the battery. The part of the heating system comprised in the cartridge can be for example formed by a resistance wound around a wick and a pair of contacts cooperating with the corresponding pair of the contacts of the aerosol generation device to connect electrically the resistance to the battery. In variant, the cartridge can be connected wirelessly to the aerosol generation device. In this case, the contacts are replaced by a primary and a secondary winding integrated respectfully into the aerosol generation device and the cartridge to generate an electric current for the resistance, by magnetic induction. According to some other examples, heat can be transmitted directly between the cartridge and the aerosol generation device using for example heating plates integrated in both device and cartridge.
One can conceive that the heating system distribution, as proposed in the art, between an aerosol generation device and a removable cartridge increases the structure complexity and the cost of both elements. This requires adding additional components notably into the cartridge that increases its structure and cost and make more difficult its recycling.

SUMMARY OF THE INVENTION

One of the aims of the present invention is to propose a heating system adapted to be used by an aerosol generation device and a removable cartridge without increasing structure complexity and costs of these elements. The invention also allows cartridge recycling in a simple way.
For this purpose, the invention relates to a heating system for an aerosol generation assembly comprising an aerosol generation device and a cartridge designed to operate with the aerosol generation device the aerosol generation device comprising a battery and the cartridge comprising a storage portion for storing an aerosol forming precursor and extending along a cartridge axis between a device end and a mouthpiece end.
The heating system comprises a heating circuit comprising an AC source connected to the battery, a coil intended to be arranged around the storage portion along the cartridge axis and connected to the AC source, and susceptor filings arranged or able to be arranged in the storage portion along the cartridge axis and a control module configured to control the operation of the heating circuit to generate heat into the storage portion by currents induced in the susceptor filings by the coil.
Indeed, using these features, it is possible to heat the precursor stored in the storage portion by currents passing through the susceptor filings and induced by the coil which may be arranged outside the cartridge. Thus, there is no need to provide complex internal components (as a wick or resistance) inside the cartridge to transfer heat. Hence, the cartridge structure or more globally the structure of a precursor storage portion can be simplified which decreases the cost of the cartridge or the whole aerosol generation assembly and makes its recycling simpler.
According to some embodiments, the susceptor filings are fixed into the storage portion along the cartridge axis on insulating supports.
Thanks to these features, the precursor heating can be optimized since the position of the susceptor filings is predetermined.
According to some embodiments, the susceptor filings are suspended in the precursor or mixed with the precursor and able to be arranged at least temporary along the cartridge axis.
Thanks to these features, the internal structure of the storage portion can be further simplified as no support is required for the susceptor filings. In this case, the concentration of the susceptor filings in the storage portion can be optimized to ensure optimal precursor heating. In some examples, the cartridge or the aerosol generation device can be shaken before using in order to optimize the disposition of the susceptor filings.
According to some embodiments, the AC source and the coil are arranged within the aerosol generation device.
Thanks to these features, only the susceptor filings are needed to be arranged within the storage portion. All other components of the heating system can arranged outside the cartridge.
According to some embodiments, a measuring circuit configured to generate measurements relative to a precursor level in the storage portion, the control module being configured to control the operation of the heating circuit basing on these measurements.
Thanks to these features, the precursor level in the storage portion can be determined. This makes it possible for example to avoid heating an empty storage portion.
According to some embodiments, the control module is configured to control the operation of both circuits using time-division multiplexing where the operation times of both circuits are mutually exclusive.
Thanks to these features, the operation of each of the circuits is not disrupted by the other circuit.
According to some embodiments, the measuring circuit comprises a pair of electrodes configured to be arranged on opposite sides of the storage portion, said measurements being measurements of the capacitance between the electrodes.
Thanks to these features, the measuring circuitry can be arranged entirely outside the storage portion.
According to some embodiments, each electrode is configured to be adjacent to one of the ends of the cartridge perpendicularly to the cartridge axis.
According to some embodiments, one of the electrodes is arranged between the storage portion and a mouthpiece of the aerosol generation device or the cartridge.
Thanks to these features, it is possible to arrange the measuring circuit in respect with the heating circuit.
According to some embodiments, the measuring circuit further comprises a function generator configured to generate a measuring signal on at least one of the electrodes a buffer configured to acquire a response signal from one of the electrodes and an amplifier configured to amplify the response signal and to deliver the amplified response signal to the control module.
Thanks to the function generator, it is possible to generate a signal suitable to measure the capacitance between the electrodes and determine from this capacitance the precursor level into the storage portion. Thanks to the buffer, a response signal from one the electrodes can be preserved and thus, the accuracy of the capacitance measurements can be improved. Thanks to the amplifier, even little changes in the capacitance may be measured.
According to some embodiments, the measuring circuit is arranged entirely within the aerosol generation device, the pair of electrodes being designed to be in contact with a cartridge housing delimiting the storage portion.
Thanks to these features, the structure of the cartridge can be further simplified.
According to some embodiments, at least one of the electrodes forms partially a cartridge housing delimiting the storage portion.
Thanks to these features, it is possible to optimize the arrangement of the electrodes to improve the accuracy of the capacitance measurements.
The invention also relates to a cartridge comprising:

a storage portion for storing an aerosol forming precursor and extending along a cartridge axis between a device end and a mouthpiece end;
a cartridge housing delimiting the storage portion ;
susceptor filings arranged or able to be arranged in the storage portion along the cartridge axis and able to interact with an electrical current induced by a coil of the heating system as described here above.

The invention also relates to an aerosol generation device comprising a battery and a control module and at least a part of a heating circuit of the heating system as described here above.
The invention also relates to an aerosol generation assembly comprising:

a cartridge as described here above;
an aerosol generation device as described here above.

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 diagram showing an aerosol generation assembly according to a first embodiment of the invention, the aerosol generation assembly comprising a heating system according to the invention;
Figure 2 is a schematic diagram showing the heating system of Figure 1; and
Figure 3 is a schematic diagram showing an aerosol generation assembly according to a second embodiment of the invention.

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 generation device" or "device" may include a vaping device to deliver an aerosol to a user, including an aerosol for vaping, by means of aerosol generating unit (e.g. an aerosol generating element which generates vapor which condenses into an aerosol before delivery to an outlet of the device at, for example, a mouthpiece, for inhalation by a user). 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 a heater system 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 vapor 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 heater and/or 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 precursor 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 vapor. Aerosol may include one or more components of the precursor.
As used herein, the term "aerosol-forming precursor" or "precursor" or "aerosol-forming substance" or "substance" may refer to one or more of a: liquid; solid; gel; mousse; foam or other substances. The precursor may be processable by the heating system of the device to form an aerosol as defined herein. The precursor may comprise one or more of: nicotine; caffeine or other active components. The active component may be carried with a carrier, which may be a liquid. The carrier may include propylene glycol or glycerin. A flavoring may also be present. The flavoring may include Ethylvanillin (vanilla), menthol, Isoamyl acetate (banana oil) or similar. A solid aerosol forming substance may be in the form of a rod, which contains processed tobacco material, a crimped sheet or oriented strips of reconstituted tobacco (RTB).

FIRST EMBODIMENT OF THE INVENTION

Referring to Figure 1, an aerosol generation assembly 10 according to the invention comprises an aerosol generation device 12 and a removable cartridge 14.
The aerosol generation device 12 comprises a device housing 21 extending between a battery end 22 and a mouthpiece end 24 along a device axis X.
The device housing 21 delimits an interior part of the aerosol generation device 12 comprising a power block 32 designed to power the device 12, at least a part of a heating system 34 powered by the power block 32, and a controller 36. The device housing 21 also defines a payload compartment 38 which may be arranged in the interior part of the device 12 or/and defined at least partially by at least one wall of the device housing 21. Additionally, on the mouthpiece end 24, the device housing 21 defines a mouthpiece 40. The mouthpiece 40 is in a fluid communication with the payload compartment 38 and defines an airflow outlet configured to deliver aerosol to the user when the aerosol generation device 12 is operated with the cartridge 14. The device housing 21 may further comprise other internal components performing different functionalities of the device 12 known in the art.
It should be noted that Figure 1 presents only a schematic diagram of different components of the aerosol generation device 12 and does not necessarily show the real physical arrangement and dimensions of these components. Particularly, such an arrangement can be chosen according to the design of the aerosol generation device 12 and technical features of its components.
The power block 32 comprises a battery and a battery charger. The battery is for example a known battery designed to be charged using the power supply furnished by an external source and to provide a direct current of a predetermined voltage. The battery charger is able to connect the battery to the external source and comprises for this purpose a power connector (like for example a mini-USB connector) or wireless charging connector. The battery charger is also able to control the power delivered from the external source to the battery according for example a predetermined charging profile. Such a charging profile can for example define a charging voltage of the battery depending on its level of charge.
The payload compartment 38 defines a cavity designed to receive the cartridge 14. In the preferred embodiment of the invention, the cavity has a cylindrical shape. In the example of figure 1, the payload compartment 38 extends along the device axis X between a pair of parallel walls 41, 42 of the device housing 21. In the same example, the payload compartment 38 is further delimited by at least one side wall 43 extending between the parallel walls 41, 42 along the device axis X. In this case, the payload compartment 38 may further define an opening used to insert the cartridge 14 into the payload compartment 38. The opening may for example extend perpendicularly to the device axis X and is formed when a removable part of the device housing 21 is moved away from a fixed part of the device housing 21 including notably the payload compartment 38. The removable part can for example comprise the mouthpiece 24 and the wall 42. The removable part can be hinged or screwed to the fixed part.
Each of the parallel walls 41, 42 is for example perpendicular to the device axis X. The wall 41 is adjacent to the battery end 22 and defines a hole suitable for an airflow passage between an airflow channel formed inside the device housing 21 and the cartridge 14. The wall 42 is adjacent to the mouthpiece end 24 and defines a hole suitable for an airflow passage between the cartridge 14 and the airflow outlet of the mouthpiece 40.
The cartridge 14 comprises a cartridge housing 51 and the part of the heating system 34 not comprised in the aerosol generation device 12 as it will be explained below in further detail. The cartridge housing 51 extends along a cartridge axis Y between a device end and a mouthpiece end, and defines at these ends two parallel walls 61, 62 perpendicular to the cartridge axis Y and at least one lateral wall 63 extending along the cartridge axis Y between the parallel walls 61, 62. In the preferred embodiment of the invention, the cartridge housing 51 has a cylindrical shape. In this case, the parallel walls 61, 62 can have a circular shape. The walls 61, 62, 63 of the cartridge housing 51 are made of a dielectric material like for example a plastic material. Advantageously, according to the invention, the walls 61, 62, 63 can form a single piece made by an appropriate industrial process. The walls 61, 62, 63 of the cartridge housing 51 delimit a storage portion 66 configured to store the aerosol forming precursor.
When the cartridge 14 is received into the payload compartment 38 of the aerosol generation device 12, the cartridge axis Y coincides with the device axis X and the parallel walls 61, 62 of the cartridge housing 51 are in contact with the parallel walls 41, 42 of the payload compartment 38. Particularly, in this case, the wall 61 is in contact with the wall 41 and defines an airflow inlet facing the corresponding hole of the wall 41 to allow entering the airflow into in the cartridge 14. Similarly, the wall 62 is in contact with the wall 42 and defines an airflow outlet facing the corresponding hole of the wall 42 to allow evacuating the airflow from the cartridge 14.
Figure 2 shows in more detail the heating system 34. Referring to this Figure 2, the heating system 34 comprises a heating circuit 72 for heating the precursor, a measuring circuit 74 for measuring a precursor level in the storage portion and a control module 76 for controlling the operation of both circuits 72, 74.
The heating circuit 72 comprises an AC source 80, a coil 82, susceptor filings 84 and optionally, a boost converter 86.
The AC source 80 is connected to the battery of the power block 32 through an SPDT switch 87 and eventually through the boost converter 86. In this last case, the boost converter 86 makes it possible to increase voltage provided by the battery on the inlet of the AC source 80. The AC source 80 presents a DC/AC inverter configured to transform the direct current provided by the battery or the boost converter 86 into an alternative current in its outlet to power the coil 82. The AC source 80 and eventually the boost converter 86 are arranged into the interior part defined by the device housing 21.
The coil 82, also visible on Figure 1 on dashed line, is intended to be arranged around the storage portion 66 of the cartridge 14 along the cartridge axis Y when the cartridge 14 is received into the payload compartment 38. Particularly, in the example of Figure 1, the coil 82 is intended to extend around the lateral wall 63 of the cartridge housing 51, and preferably, significantly along the whole length of the lateral wall 63. For this purpose, the coil 82 is integrated into the side wall 43 of the payload compartment 38 or protrudes from this side wall 43 to extend around the payload compartment 38 along the device axis X. Thus, the coil 82 is integrated into the device 12 and when the cartridge 14 is received into the payload compartment 38, the coil 82 extends around the lateral wall 63 of the cartridge housing 51 and consequently, around the storage portion 66 of the cartridge 14.
The susceptor filings 84 are arranged or able to be arranged into the storage portion 66 of the cartridge 14, preferably along the cartridge axis Y. Particularly, according to one example of the invention, the susceptor filings 84 are fixed into the storage portion 66 along the cartridge axis Y on insulating supports. The insulating supports can be made of the same material as the cartridge walls 61, 62, 63. According to another example, the susceptor filings 84 are suspended in the precursor or mixed with the precursor and able to be arranged at least temporary along the cartridge axis Y. Such an arrangement can for example be achieved by shaking the cartridge 14 or the device 12 with the cartridge 14 before using.
According to the preferred embodiment of the invention, the susceptor filings 84 can present thin elongated filings of 1 mm or 2 mm long, as for example wire cuttings or metal strips of 1 mm or 2 mm long. The wire thickness can be for example comprised between 0,05 mm and 0,5 mm. The strip thickness may be comprised in the same range or between for example 0,1 mm and 0,5 mm. In variant, the susceptor filings 84 in the shape of square flakes may be used. More generally, the dimensions and/or the shape of the susceptor filings 84 may be chosen to optimize heating in the applied magnetic field. The susceptor filings 84 can be made of any suitable material, notably a metal material. The susceptor filings 84 can be also coated to prevent corrosion.
When the susceptor filings 84 are placed into the magnetic field created by the coil 83, currents appear in the filings 84 and then, transformed into heat which is transferred to the precursor.
The measuring circuit 74 is configured to generate measurements relative to a precursor level in the storage portion 66. The measuring circuit 74 comprises a pair of electrodes 91, 92, a function generator 93, a resistance 94, a buffer 95 and an amplifier 96. According to the first embodiment of the invention, the measuring circuit 74 is arranged entirely in the device 12.
The pair of electrodes 91, 92 are formed for example by a pair of capacitive plates and are intended to be arranged on opposite sides of the storage portion 66 so as the storage portion 66 forms a capacitor. According to the first embodiment of the invention, the electrodes 91, 92 are arranged in the payload compartment 38 of the device housing 21 and are able to come in contact with the parallel walls 61, 62 of the cartridge housing 51 when the cartridge 14 is inserted into the payload compartment 38. For this purpose, the electrodes 91, 92 may for example protrudes from the parallel walls 41, 42 delimiting the payload compartment 38. According to another example of the invention, the electrodes 91, 92 are integrated into these parallel walls 41, 42 or form these walls 41, 42. One of the electrodes, for example the electrode 91, is called positive electrode, and the other is called negative electrode. As it is showed on Figure 2, the electrodes 91, 92 are connected to the battery through the function generator 93, the SPDT switch 87 and the resistance 94. The electrodes 91, 92 are also connected to the control module 76 through the function generator 93 and the resistance 94.
The function generator 93 is configured to generate a measuring signal on at least one of the electrodes, for example on the positive electrode 91. The resistance 94 is connected between the positive electrode 91 and the function generator 93. The resistance value of the resistance 94 is chosen to optimize the capacitance measuring process between the electrodes 91, 92. The buffer 95 is connected between the positive electrode 91 and the control module 76 and is able to acquire and store a response signal from the positive electrode 91. The amplifier 96 is connected between the buffer 95 and the control module 76. The amplifier 96 is able to amplify the response signal acquired by the buffer to deliverer the amplified signal to the control module 76.
The control module 76 is configured to control the operation of the heating system 34 by controlling the operation of both circuits 72, 74. For this purpose, the control module 76 is connected to a command terminal of the SPDT switch 87 and is able to send to this terminal a control command (for example a XOR switch command) to power only the heating circuit 72 or only the measuring circuit 74. Thus, the control module 76 is configured to control the operation of both circuits 72, 74 using time-division multiplexing where the operation times of both circuits 72, 74 are mutually exclusive. The control module 76 is also configured to control the operation of the function generator 93 and acquire the amplified response signal from the amplifier 96. By analyzing the measuring signal generated by the function generator 93 and the amplified response signal, the control module 76 is further configured to determine capacitance values between the electrodes 91, 92 and basing on these capacitance values, determine the precursor level in the storage portion 66. Finally, basing on the determined precursor level, the control module 76 is configured to control the operation of the heating circuit 72. For example, the control module 76 can adjust the heating temperature by controlling the operation of the AC source 80.
According to a particular embodiment of the invention, the control module 76 is integrated into the controller 36 and presents for example a program code dedicated to control the heating and measuring capacities of the aerosol generation assembly. According to another embodiment of the invention, the control module 76 is formed by a separated controller similar to the controller 36 explained above.
The operation of the aerosol forming assembly 10 will now be explained. Initially, it is considered that the cartridge 14 is extracted from the aerosol generation device 12. The cartridge can be for example purchased separately from the aerosol generation device 12 and used as a consumable. When the user is intending to activate the operation of the assembly 10, he/she inserts first the cartridge 14 into the payload compartment 38 of the aerosol generation device 12. In this position, the coil 82 is arranged around the storage portion 66 of the cartridge 14 and the electrodes 91, 92 are positioned on opposite sides of the storage portion 66. Then, the user activates the operation of the controller 36 by activating for example a switch or by making a puff. This activates the operation of the control module 76 which controls the operation of the circuits 72, 74. For example, the control module 76 can first control the operation of the measuring circuit 74 to determine the precursor level in the storage portion 66. In this case, a measuring signal is generated between the electrodes 91, 92 and a response signal is then generated. The precursor level is determined by analyzing the response signal. If the storage is not empty, the control module 76 may deactivate the operation of the measuring circuit 74 and activate the operation of the heating circuit 72 by controlling the SPDT switch. In this case, the coil 82 induces electric currents on the susceptor filings 84 which are transformed into heat. The heat is transferred to the precursor. Upon expiring a predetermined time interval, the control module 76 may deactivate the operation of the heating circuit 72 and activate the operation of the measuring circuit 74.

SECOND EMBODIMENT OF THE INVENTION

An aerosol generation assembly 110 according to a second embodiment of the invention is showed on Figure 3.
As in the previous case, the aerosol generation assembly 110 comprises an aerosol generation device 112 and a cartridge 114. The aerosol generation device 112 also defines a payload compartment 138 able to receive the cartridge 114 and delimited along a device axis X by parallel walls 141, 142 similar to the parallel walls 41, 42 explained above. The cartridge 114 also defines a storage portion 166 delimited by parallel walls 161, 162 along a cartridge axis Y. The assembly 110 also comprises a heating system 134 operation of which is similar to the operation of the heating system 34 explained above. The heating system 134 comprises notably a pair of electrodes 191, 192 used to measure the precursor level in the storage portion 166 and formed for example by a pair of capacitive plates.
Contrary to the previous case, the electrodes 191, 192 are not integrated into the device 112 but form at least partially a cartridge housing of the cartridge 114. According to the example of Figure 3, the electrodes 191, 192 are adjacent to respectfully to the parallel walls 161, 162 of the cartridge 114 on external sides of these walls 161, 162. Advantageously, the electrodes 191, 192 can be tightly fitted with these walls 161, 162 which are, like in the previous case, made of a dielectric material. According to another example, the electrodes 191, 192 form the walls 161, 162 or are integrated into these walls, and can for example be in contact with the precursor. According to an example of the second embodiment, the cartridge 114 may further comprise a mouthpiece arranged adjacent to the electrode 192. In this case, no mouthpiece arrangement is needed for the device 112. This can simplify the structure of the payload compartment 138.
In a variant of the second embodiment, one of the electrodes 191, 192 is integrated into the device 112 and the other into the cartridge 114. For example, the electrode 191 may be arranged in the device 112 as the electrode 91 according to the first embodiment and the electrode 192 may be arranged in the cartridge 114 as explained above.

OTHER EMBODIMENTS OF THE INVENTION

Other embodiments of the heating system and the aerosol generation assembly according to the invention are also possible. For example, different components of the heating system may be arranged differently in respect with the device and the cartridge. Particularly, the cartridge may comprise some other components of the heating system, as for example the coil. The heating system according to the invention may also be used in an aerosol generation device comprising a fixed precursor storage portion. In this case, the heating system is arranged entirely within the device housing with a core around the precursor storage portion and electrodes on opposite sides of it. The measuring circuit of the heating system according to the invention may also be implemented differently, for example without electrodes, by using an appropriate sensor.

Claims

A heating system (34; 134) for an aerosol generation assembly (10; 110) comprising an aerosol generation device (12; 112) and a cartridge (14; 114) designed to operate with the aerosol generation device (12; 112), the aerosol generation device (12; 112) comprising a battery and the cartridge (14; 114) comprising a storage portion (66; 166) for storing an aerosol forming precursor and extending along a cartridge axis (Y) between a device end and a mouthpiece end;
the heating system (34; 134) comprising:
- a heating circuit (72) comprising an AC source (80) connected to the battery, a coil (82) intended to be arranged around the storage portion (66; 166) along the cartridge axis (Y) and connected to the AC source (80), and susceptor filings (84) arranged or able to be arranged in the storage portion (66; 166) along the cartridge axis (Y);

- a control module (76) configured to control the operation of the heating circuit (72) to generate heat into the storage portion (66; 166) by currents induced in the susceptor filings (84) by the coil (82).
The heating system (34; 134) according to claim 1, wherein the susceptor filings (84) are fixed into the storage portion (66; 166) along the cartridge axis (Y) on insulating supports.
The heating system (34; 134) according to claim 1, wherein the susceptor filings (84) are suspended in the precursor or mixed with the precursor and able to be arranged at least temporary along the cartridge axis (Y).
The heating system (34; 134) according to any one of the preceding claims, wherein the AC source (80) and the coil (82) are arranged within the aerosol generation device (12; 112).
The heating system (34; 134) according to any one of the preceding claims, further comprising a measuring circuit (74) configured to generate measurements relative to a precursor level in the storage portion (66; 166), the control module (76) being configured to control the operation of the heating circuit (72) basing on these measurements.
The heating system (34; 134) according to claim 5, wherein the control module (76) is configured to control the operation of both circuits (72, 74) using time-division multiplexing where the operation times of both circuits are mutually exclusive.
The heating system (34; 134) according to claim 5 or 6, wherein the measuring circuit (74) comprises a pair of electrodes (91, 92; 191, 192) configured to be arranged on opposite sides of the storage portion (66, 166), said measurements being measurements of the capacitance between the electrodes (91, 92; 191, 192).
The heating system (34; 134) according to claim 7, wherein each electrode (91, 92; 191, 192) is configured to be adjacent to one of the ends of the cartridge (14; 114) perpendicularly to the cartridge axis (Y).
The heating system (34; 134) according to any one of claims 7 to 8, wherein one of the electrodes (92; 192) is arranged between the storage portion (66; 166) and a mouthpiece (40) of the aerosol generation device (12; 112) or the cartridge (14; 114).
The heating system (34; 134) according to any one of claims 7 to 9, wherein the measuring circuit (74) further comprises a function generator (93) configured to generate a measuring signal on at least one of the electrodes (91, 92; 191, 192), a buffer (95) configured to acquire a response signal from one of the electrodes (91, 92; 191, 192) and an amplifier (96) configured to amplify the response signal and to deliver the amplified response signal to the control module (76).
The heating system (34) according to any one of claims 7 to 10, wherein the measuring circuit (74) is arranged entirely within the aerosol generation device (12), the pair of electrodes (91, 92) being designed to be in contact with a cartridge housing (51) delimiting the storage portion (66).
The heating system (134) according to any one of claims 7 to 10, wherein at least one of the electrodes (191, 192) forms partially a cartridge housing delimiting the storage portion (166).
A cartridge (14; 114) designed to operate with an aerosol generation device (12; 112) and comprising:
- a storage portion (66; 166) for storing an aerosol forming precursor and extending along a cartridge axis (Y) between a device end and a mouthpiece end;

- a cartridge housing (51) delimiting the storage portion (66; 166);

- susceptor filings (84) arranged or able to be arranged in the storage portion (66; 166) along the cartridge axis (Y) and able to interact with an electrical current induced by a coil (82) of the heating system (34; 134) according to any one of the preceding claims, to generate heat.
An aerosol generation device (12; 112) designed to operate with a cartridge (14; 114) and comprising:
- a battery;

- a control module (76) and at least a part of a heating circuit (72) of the heating system (34; 134) according to any one of claims 1 to 12.
An aerosol generation assembly (10; 110) comprising:
- a cartridge (14; 114) according to claim 13;

- an aerosol generation device (12; 112) according to claim 14.