Aerosol generating device and operation method of such a device

Abstract

The present invention concerns an aerosol generating device (10) comprising a control unit (14) configured to power an aerosol generating unit (12) to heat a vaporizable material to generate aerosol. The control unit (14) is configured to power the aerosol generating unit (12) during a predetermined loading time to generate a predetermined amount of aerosol, the predetermined loading time being equal to, or strictly less than, 3.0 sec.

Description

[0001] Aerosol generating device and operation method of such a device

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to an aerosol generating device.

[0004] The present invention also relates to an operation method of such an aerosol generating device.

[0005] BACKGROUND OF THE INVENTION

[0006] Different types of aerosol generating devices are already known in the art. Generally, such devices comprise a storage portion for storing a vaporizable material, 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 vaporizable material 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.

[0007] Different types of heating systems can be used to heat the vaporizable material in such devices. For example, in case of a liquid vaporizable material, a heating system may be formed by a resistance arranged in the flow path and wound around a wick in communication with the liquid vaporizable material. Thus, carried by the wick, the vaporizable material can be evaporated by the resistance arranged in the flow path. It is also known to provide a porous wick, for example made of ceramic material, having an heater (e.g. an electric heater) arranged on a surface of the porous wick. The liquid is transported from the reservoir through the porous wick towards the heating element.

[0008] The amount of the generated aerosol is a key factor of operation of an aerosol generating device that greatly impacts the user satisfaction. As an example, applying too much heat in order to generate a higher amount of aerosol will result in a “burnt taste” and in the creation of harmful, undesirable components such as aldehydes. In addition, for such higher heat to be reached more energy is required, which results in the need of usage of a bigger size battery cell, thus having an impact on device size. In other words, developing a proper and effective heat control for a desired aerosol generation while meeting all requirements from technical development, quality, safety and cost point of view, presents a significant challenge in designing the aerosol generating devices.

[0009] SUMMARY OF THE INVENTION

[0010] One of the aims of the present invention is to provide an aerosol generating device and a corresponding operation method which allow to improve aerosol generation properties of an aerosol generating device while keeping an optimal consumption and vapor delivery for the user. Therefore, the user satisfaction can be greatly increased.

[0011] For this purpose, the invention relates to an aerosol generating device comprising a control unit configured to power an aerosol generating unit to heat a vaporizable material to generate aerosol; wherein the control unit is configured to power the aerosol generating unit during a predetermined loading time to generate a predetermined amount of aerosol, the predetermined loading time being equal to, or strictly less than, 3.0 sec.

[0012] It has to be noted that in the present disclosure “sec” or “s” is used to indicate the second, i.e. the SI unit of time.

[0013] The aerosol generating unit may refer or comprise a heater (either resistive or inductive), a spray, an ultrasonic transducer or any type of mechanism to generate the aerosol from the vaporizable material.

[0014] In some embodiments, the control unit is configured to power the aerosol generating unit by an output voltage or an output power to heat the vaporizable unit. According to some other embodiments, the control unit is configured to power the aerosol generating unit according to any other suitable way (electrically or mechanically) to heat the vaporizable unit.

[0015] As used hereinafter, “loading time” refers to the operation time of the aerosol generating unit within it generates aerosol. In other words, the loading time refers herein to the operation time wherein a load is applied to the heater so that it provides heat to the vaporizable material to generate aerosol. In other words, the loading time differs from any other time range within no aerosol is generated such for example a pre-heating time range. Advantageously, the loading time corresponds to a single user puff. In other words, as disclosed above, after the loading time and in general outside the loading time (i.e. not within the loading time), the control unit is configured to not power the aerosol generating unit to generate aerosol. For example, when the loading time is lapsed, the aerosol generating unit is not powered to generate aerosol until detecting a new puff or until any other triggering event. Out of the loading periods (i.e. not within the loading time), the control unit can still be configured to power the aerosol generating unit for example to maintain it ready to use (for example as in the pre-heating time range mentioned above) but to not generate aerosol.

[0016] It has to be noted that irrespective of the way the heater is loaded and heat is provided to vaporizable material to generate aerosol, the invention controls heater to no longer provide a load to the heater so that the aerosol generation is stopped at 3.0 sec or at a defined time lower than 3.0 sec. Advantageously, with the aerosol generating device according to the invention the vaporizable material is heated for less than 3.0 sec, contrary to the conventional aerosol generating device known in the art.

[0017] In some embodiments, the predetermined loading time is strictly less than 3.0 sec, preferably comprised between 1.5 sec. and 2.5 sec, more preferably comprised between 1.9 sec and 2.3 sec, and is advantageously substantially equal to 2.0 sec.

[0018] These durations of the predetermined loading time correspond to an average duration of a puff practiced by the users, as discovered by the inventors. Therefore, a longer duration of the heating time is generally not necessary.

[0019] In some embodiments, the predetermined amount of aerosol is more than 4.5 mg, preferably comprised between 4.5 mg and 12 mg, and the loading time is between 2.0 sec and 3.0 sec, preferably the loading time is 2.0 sec.

[0020] In some embodiments, the control unit is configured to power the aerosol generating unit to generate at least one of the following amounts of aerosol at a given instant within the loading time:

[0021] - at 2.9 sec: more than 5.0 mg, more preferably more than 7.4 mg;

[0022] - at 2.5 sec: more than 4.0 mg, more preferably more than 5.9 mg;

[0023] - at 2.0 sec: more than 3.0 mg, more preferably more than 4.5 mg;.

[0024] - at 1.5 sec: more than 2.0 mg, more preferably more than 3.1 mg; - at 1 sec: more than 1.0 mg, more preferably more than 1.8 mg.

[0025] In some embodiments, the target amount of aerosol generated is placed at the lower end of the above-mentioned intervals, within the specific loading time. Therefore, according to a possible embodiment, the invention proposes to reduce the loading time while keeping the output power at low level, preferably at 6.5W- 7W. As such, the aerosol properties are not changed. Since the aerosol generating unit is powered less time, the resulting power consumption is reduced. This greatly improves the user experience.

[0026] In some embodiments, the amount of aerosol is placed at the above-mentioned interval, corresponding to a higher amount of aerosol received by the user within the specific loading time. Therefore, the invention proposes to reduce the loading time, preferably at an output power of 7.1 W- 9.4W, more preferably of 7.5W- 8.5W, which will increase the rate of generated aerosol. As such, according to a possibile embodiment, the aerosol generation is thus concentrated within a shorter loading time, making the aerosol more concentrated with the desired compounds of interest such as aerosolized / carrier molecules PG and VG, without negatively affecting its taste. Additionally, since the aerosol generating unit is powered less time, the resulting power consumption can be reduced. This greatly improves the user experience.

[0027] In some embodiments, the target amount of aerosol is even greater than the two embodiments above, corresponding to a high amount of aerosol received by the user within the specific loading time. Therefore, according to a possible embodiment, the invention proposes to reduce the loading time, preferably at an output power of 9.5W- 19.5W, more preferably 9.6W - 10.5W, which will increase the rate of generated aerosol. As such, according to a possibile embodiment, the aerosol generation is thus concentrated within a shorter loading time, making the aerosol more concentrated with the desired compounds of interest such as aerosolized / carrier molecules PG and VG, without negatively affecting its taste. Additionally, since the aerosol generating unit is powered less time, there may be no impact of the resulting power consumption. This greatly improves the user experience.

[0028] The amount of the generated aerosol was measured according to Coresta Recommended Method (CRM) no. 81. This method notably comprises trapping the generated aerosol within a filter trap and measuring the amount of the trapped aerosol. In other words, the testing apparatus disclosed in the Coresta Recommended Method (CRM) no. 81 can be used to measure the quantity of generated aerosol according to the invention by fluidically connecting the aerosol generating device to the testing apparatus so that the generated aerosol can be trapped in the filter trap. Advantageously, the measurements are performed using a model liquid mixture of PG, VG and water taken respectively in the following rates 45%:45%:10%.

[0029] The loading time of activation of the aerosol generating unit can be measured in in different ways for example by measuring the time while the heater is active, i.e. powered, to generate aerosol.

[0030] According to some embodiments, the control unit is configured to power an aerosol generating unit by an output power, wherein the output power is equal to, or strictly greater than, 6.5W.lt was discovered by the inventors that these values of the output power ensure the generation of a desired amount of aerosol within the predetermined loading time without negatively affecting the aerosol taste. Therefore, the aerosol generating unit powered by an output power according to these values can generate a desired amount of aerosol, as explained above.

[0031] According to possible embodiments, the output power is comprised between 6.5W and 7.0W.

[0032] According to possible embodiments, the output power is comprised between 7.1W and 9.4W, preferably between 7.5W and 8.5W.

[0033] According to possible embodiments, the output power is between 9.5W and 19.5W, preferably between 9.6W and 10.5W.

[0034] In all embodiments, the aerosol generating unit is configured to be either constant voltage or constant power controlled.

[0035] Pulse modulation for power delivery, such as Pulse Wiidth Modulation (PWM) or Pulse Frequency Modulation (PFM) is used to achieve the same results.

[0036] According to some embodiments, the output power is a substantially constant value. A higher value of the output power can ensure a higher amount of aerosol generated within the predetermined loading time. According to some embodiments, the output power is a decreasing value by steps. The maximal power value (i.e. the power value of the first step) can be comprised within the above-mentioned intervals. In some embodiments, each power value is comprised between 5.0 W and 19.5 W. The average power is always greater or equal than 6.5W.

[0037] It has to be noted that in the case the output power is controlled to decrease and / or increase during the loading time, the average power is equal to, or greater than, 6.5W. Preferably, the output power intervals disclosed herein are applicable to the average power, in the case the output power is controlled to decrease and / or increase during the loading time.

[0038] These features make it possible to generate a higher amount of aerosol at the beginning of the puff.

[0039] According to some embodiments, the aerosol generating device is configured to ensure a pressure drop above 20 mmWg and less than 80 mmWg, advantageously less than 70 mmWg, preferably less than 60 mmWg and more preferably less than 50 mmW.

[0040] The pressure drop, also known as resistance to draw, can for example be measured following Coresta Recommended Method (CRM) no. 41 , “Determination of the Draw Resistance of Cigarettes and Filter Rods”.

[0041] It was discovered by the inventors that the duration of the puff can be influenced by the pressure drop in the aerosol generating device. For example, a device that has a lower pressure drop than a reference device has an increase of the airflow, which results in reaching the same amount of aerosol in a shorter amount of time. Therefore, a desired duration of an average puff can be achieved by controlling the pressure drop of the device.

[0042] The above-mentioned values of the pressure drop can conduct to an average duration of a user puff less than 3.0 sec. Thus, the heating time of the vaporizable material can match an average duration of a user puff practiced on the device according to the invention. This allows to make the device suitable for using by most of the users, independently from their habits.

[0043] In some embodiments, said predetermined amount of aerosol is generated per user Therefore, the predetermined loading time as defined above corresponds to a single user puff.

[0044] According to some embodiments, the control unit is configured to power the aerosol generating unit during the predetermined loading time further to detection of a user puff. Advantageously, each detection of a user puff triggers powering of the aerosol generating unit during the predetermined loading time, as previously defined. Alternatively, instead of detection of a user puff, any other triggering event such for example activation of the aerosol generating device by the user can be used to trigger the powering of the aerosol generating unit during the predetermined loading time.

[0045] The user puff can be detected using for example a puff sensor.

[0046] The invention also concerns an operation method of an aerosol generating device as defined above. The method comprises a step of powering of an aerosol generating unit during a predetermined loading time to generate a predetermined amount of aerosol. The control unit can be configured to execute a software, and in general computer implemented instructions, for executing on or more method step(s) to control the aerosol generating device and in particular to provide a load to the aerosol generating unit during the above- mentioned predetermined loading time to generate a predetermined amount of aerosol.

[0047] BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The invention and its advantages will be better understood upon reading the following description, which is given by way of non-limiting example and which is made with reference to the appended drawings, in which:

[0049] - Figure 1 is a schematic diagram showing an aerosol generating device according to the invention; and

[0050] - Figures 2 and 3 are different illustrations of an operation method of the aerosol generating device of Figure 1.

[0051] DETAILED DESCRIPTION OF THE INVENTION Before describing the invention, it is to be understood that the invention is not limited to the details of construction or process steps set forth in the following description. It will be apparent to those skilled in the art having the benefit of the present disclosure that invention is capable of other embodiments and of being practiced or being carried out in various ways.

[0052] As used herein, the term “aerosol generating device” or “device” may include an inhaling device (inhaler) to deliver an aerosol to a user. The inhaling device includes an aerosol precursor, an aerosol generating unit (e.g. a heater or atomizer) which generates vapor from the aerosol precursor, an air flow channel condenses the generated vapor into an aerosol, and a mouthpiece being fluidly connected to the air flow channel and provided at an outlet of the device. The device may be portable. The term “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 an atomizer 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 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 regardless of the amount of substrate (pre-cursor) available at the aerosol generating unit and regardless of the strength with which a user inhales.

[0053] As used herein, the term “control unit” refers to a component configured to be part of the aerosol generating device for controlling according to the invention. The control unit is configured to control the operation of the device according to a determined operation configuration. Thus, the control unit can control the operation of the heater and / or the power provided for example by a battery and / or the pressure of the precursor or the air. The control unit may be realized by single integrated chip (e.g., MCU or MPU), or a combination of multiple integrated chips, or a combination of at least one integrated chip and peripherals. A whole of a printed circuit board assembly comprising a circuit board and aggregation of electronics may be deemed as the control unit.

[0054] As used herein, the term “aerosol” or “vapor” 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 “vaporizable material” or “precursor” or “aerosol-forming substance” or “substance” may refer to one or more of a: liquid; solid; gel; mousse; other substance. The precursor may be processable by an atomizer of the device to form an aerosol. The precursor may comprise one or more of: nicotine; caffeine or other active component. 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).

[0055] As used herein, the term “substantially equal” refers to an equivalence relation with an error margin less than 10%, advantageously less than 5%.

[0056] Referring to Figure 1 , an aerosol generating device 10 according to the invention is first described.

[0057] Particularly, the aerosol generating device 10 comprises an aerosol generating unit 12 configured to generate aerosol from a vaporizable material 16, a control unit 14 configured to supply a power profile to the aerosol generating unit 12 and advantageously, a puff sensor 18 configured to generate data characterizing user puffs. The aerosol generating device 10 may further comprise other components performing different functionalities of the device 10, such as a battery 20 for powering the device 10.

[0058] It is to be understood that Figure 1 is just a schematic drawing, and appearance of the aerosol generating device 10, arrangements of the vaporizable material 16, the aerosol generating device 12, the control unit 14, the puff sensor 18 and the battery 20 can be modified.

[0059] The battery 20 is for example a known battery designed to be charged using a power supply furnished by an external charger and to provide a direct current of a predetermined voltage (e.g., lithium-ion secondary battery). The battery 20 may be charged by at least one of wired manner and wireless manner, the control unit 14 may be configured to control the charging of the battery 20, and the aerosol generating device 10 may further comprises a power receiving port (e.g., USB receptacle and / or receiving coil) in accordance with charging manner. If the aerosol generating device 10 itself is designed as disposable type, charging mechanism (incl. power receiving port and / or charging circuit) may be omitted. In such the disposable type, a primary battery, which does not support charging, may be used as the battery 20.

[0060] The vaporizable material 16 may be stored in a compartment suitable for storing a vaporizable material, preferably a liquid vaporizable material. Such a compartment can be fixed with respect to the body of the aerosol generating device 10 or removable from it. In the first case, the compartment can be refilled with vaporizable material. In the second case, the vaporizable material 16 may be stored in a replaceable cartridge (e.g., a pod or capsule containing e-liquid) that can be removed and replaced by another one when the vaporizable material is no longer available. In some embodiments, the replaceable cartridge can be also refilled with the vaporizable material.

[0061] The aerosol generating unit 12 may comprise a heater designed to be in contact with the vaporizable material 16. Powered by the battery 20 and controlled by the control unit 14, the aerosol generating unit 12 is configured to heat the vaporizable material 16 comprised in device 10 to generate aerosol. Either one of a resistive heater, an inductive heater, or combination thereof may be employed as the heater. The aerosol generating unit 12 is not limited to the heater. A spray, an ultrasonic transducer or any type of mechanism to generate the aerosol from the vaporizable material 16 may be used.

[0062] The control unit 14 may comprise a processor embodied as various hardware-based processing means such as a micro processing unit (MPU), a coprocessor, a microcontroller unit (MCU) or various other computing or processing devices including integrated circuits. In some embodiments, the processor may be configured to execute instructions that may be stored in a memory and / or that may be otherwise accessible to the processor. As such, whether configured by hardware or by a combination of hardware and software, the processor may be capable of performing operations according to various embodiments, depending on configuration. The memory may be configured to store control software, configuration settings, and / or other data, programs, and / or the like that may be used to control operation of the aerosol generating device 10. In some embodiments, the control unit 14 is configured to process data from the puff sensor 18 and to supply a power profile to the aerosol generating unit 12, as further explained in relation to the operation method.

[0063] The puff sensor 18 may be an inhalation sensor and is capable of sensing a puff start signal. Accordingly, the puff sensor 18 is configured to at least communicate a puff start signal to the control unit 14. Based on data from the puff sensor 18, the control unit 14 is configured to supply power to the aerosol generating unit 12 as it will be explained in further detail below. The puff sensors 18 may comprise either one of a microphone sensor, a temperature sensor (e.g., a thermistor), and a flow sensor.

[0064] An operation method of the aerosol generating device 10 will now be described in reference to Figures 2 and 3.

[0065] This method comprises a step of powering the aerosol generating unit 12 during a predetermined loading time to generate a predetermined amount of aerosol. This step is for example carried out further to each detection by the control unit 14 of a user puff. For example, the control unit 14 detects a user puff upon receiving a puff start signal from the puff sensor 18. In some embodiments, said step can be carried out only once, upon for example detection of the first user puff. Alternatively, said step is carried out once or several times upon detection of any other triggering event such as for example activation of the aerosol generating device by the user.

[0066] During said step, the aerosol generating unit 12 is powered by the control unit 14 according to a power profile. Figure 2 shows two examples of the power profile defining the output power, which can be used to power the aerosol generating unit 12.

[0067] According to power profile A, the control unit 14 provides a substantially constant value of the output power. Particularly, this value is constant during the whole predetermined loading time except the ends of the interval where the power is increasing from zero to the constant value and is decreasing from this constant value to zero. The constant value of the output power can for example be comprised between 6.5 W and 19.5 W, and advantageously equal to 6.5 W to 7.0 W, or advantageously between 7.1 W to 9.4 W, more preferable between 7.5 W and 8.5 W, or advantageously between 9.5 W and 19.5 W, more preferable between 9.6 W and 10.5 W. The aerosol generating unit 12 can be controlled according to a PWM control pre-set.

[0068] According to power profile B, the control unit 14 provides an output power decreasing by steps. The output power has thus a substantially constant value at each step. A higher power value is provided at the beginning of the profile to provide a higher amount of aerosol at the beginning of the puff. In this case, the maximal power value (i.e. the power value of the first step) can be comprised within the above-mentioned intervals. In some embodiments, each power value is comprised between 5.0 W and 19.5 W. The average power level should be above or equal to 6.5 W. This power profile can for example comprise 3 steps that means that 3 power values can be successively applied within the predetermined loading time.

[0069] As it is shown in Figures 2 and 3, the predetermined loading time is strictly less than 3.0 sec and is comprised for example between 1.5 sec and 2.5 sec, more preferably comprised between 1.9 sec and 2.3 sec. Advantageously, according to possible embodiments of the invention, the predetermined loading time is substantially equal to 2.0 sec. Preferably, the predetermined loading time is greater than 0.5 sec, advantageously greater than 1.0 sec.

[0070] Within the predetermined loading time, the aerosol generating unit 12 generates a predetermined amount of aerosol. This amount is more than 4.5 mg, for example comprised between 4.6 mg and 12 mg. This amount is for example measured according to Coresta Recommended Method (CRM) no. 81. A greater amount of vapor can be generated for example with a greater power value. Advantageously, the measurements are performed using a model liquid mixture of PG, VG and water taken respectfully in the following rates 45%:45%:10%.

[0071] Other examples of predetermined amounts of aerosol generated within the loading time can be provided.

[0072] For example, for an output power equal or greater than 6.5W, preferably comprised between 6.5W and 8.5W, it is possible to generate approximately 8 mg of aerosol for a loading time substantially equal to 3.0 sec as it is shown for example in part A of Figure 3. For a same value of the output power, it is possible to generate approximately 4.6 mg of aerosol for a loading time substantially equal to 2.0 sec as it is shown for example in part B of Figure 3. Finally, for greater values of the output power of, for example, 8.1 W or 10.1 W, it is possible to generate approximately 6.5 or 7.7 mg of aerosol, respectively, for a loading time substantially equal to 2.0 sec as it is shown for example in part C of Figure 3. In parts B or C of Figure 3, the border of 3 sec corresponds to the instant when the smoking machine stops during a measuring process performed according to Coresta Recommended Method.

[0073] Moreover, at different instants of the loading time range, the following amounts of aerosol can be generated:

[0074] - at 2.9 sec: more than 5.0 mg, more preferably more than 7.4 mg; - at 2.5 sec: more than 4.0 mg, more preferably more than 5.9 mg;

[0075] - at 2.0 sec: more than 3.0 mg, more preferably more than 4.5 mg;.

[0076] - at 1.5 sec: more than 2.0 mg, more preferably more than 3.1 mg;

[0077] - at 1.0 sec: more than 1.0 mg, more preferably more than 1.8 mg.

[0078] The output power to generate these amounts can be greater than 6W, advantageously greater or equal than 6.5W.

[0079] More generally, the following correlations between the heating time, the output power and the amounts of generated aerosol can be observed:

[0080] It should be noted that the heating can be stopped at one of the above-mentioned instants so as the loading time can correspond to this instant. Therefore, for example, for a loading time comprised between 1.9 sec and 2.1 sec, and preferably equal to 2.0 sec, the amount of the generated aerosol can be more than 3.0 mg, more preferably more than 4.5 mg. For a loading time comprised between 2.4 sec and 2.6 sec, and preferably equal to 2.5 sec, the amount of the generated aerosol can be more than 4.0 mg, more preferably more than 5.9 mg. For a loading time comprised between 2.8 sec and 2.95 sec, and preferably equal to 2.9 sec, the amount of the generated aerosol can be more than 5.0 mg, more preferably more than 7.4 mg. For a loading time of 3.0 sec, the amount of the generated aerosol can be more than 6.0 mg, more preferably more than 7.4 mg.

[0081] Additionally, the operation method and the structure of the aerosol generating device 10 ensure a pressure drop above 20 mmWg and less than 80 mmWg, advantageously less than 70 mmWg, preferably less than 60 mmWg and more preferably less than 50 mmWg. The pressure drop can also be measured following the Coresta Recommended Method (CRM) no. 41 , “Determination of the Draw Resistance of Cigarettes and Filter Rods”.

Claims

CLAIMS1. An aerosol generating device (10) comprising a control unit (14) configured to power an aerosol generating unit (12) to heat a vaporizable material to generate aerosol; wherein the control unit (14) is configured to power the aerosol generating unit (12) during a predetermined loading time to generate a predetermined amount of aerosol, the predetermined loading time being equal to, or strictly less than, 3.0 sec.

2. The aerosol generating device (10) according to claim 1 , wherein the predetermined loading time is strictly less than 3.0 sec, preferably comprised between 1.5 sec and 2.5 sec, more preferably comprised between 1.9 sec and 2.3 sec, most preferably it is equal to 2.0 sec.

3. The aerosol generating device (10) according to any one of the preceding claims, wherein the control unit (14) is configured to power the aerosol generating unit (12) to generate at least one of the following amounts of aerosol at a given instant within the loading time:- at 2.9 sec: more than 5.0 mg, more preferably more than 7.4 mg;- at 2.5 sec: more than 4.0 mg, more preferably more than 5.9 mg;- at 2.0 sec: more than 3.0 mg, more preferably more than 4.5 mg;- at 1.5 sec: more than 2.0 mg, more preferably more than 3.1 mg;- at 1.0 sec: more than 1.0 mg, more preferably more than 1.8 mg.

4. The aerosol generating device (10) according to any one of the preceding claims, wherein the predetermined amount of aerosol is more than 4.5 mg, preferably comprised between 4.6 mg and 12 mg, and the loading time is between 2.0 sec and 3.0 sec, preferably the loading time is 2.0 sec.

5. The aerosol generating device (10) according to any previous claim, wherein the control unit (14) is configured to power an aerosol generating unit (12) by an output power, wherein the output power is equal to, or greater than, 6.5W.

6. The aerosol generating device (10) according to claim 5, wherein the output power is comprised between 6.5W and 7.0W.

7. The aerosol generating device (10) according to claim 5, wherein the output power is comprised between 7.1 W and 9.4W, preferably between 7.5W and 8.5W.

8. The aerosol generating device (10) according to claim 5, wherein the output power is between 9.5W and 19.5W, preferably between 9.6W and 10.5W.

9. The aerosol generating device (10) according to any one of the preceding claims, wherein the control unit (14) is configured to power the aerosol generating unit (12) by an output voltage, wherein the output voltage is a substantially constant value or a decreasing value by steps.

10. The aerosol generating device (10) according to any one of the preceding claims, configured to ensure a pressure drop above 20 mmWg and less than 80 mmWg, advantageously less than 70 mmWg, preferably less than 60 mmWg and more preferably less than 50 mmWg.11 . The aerosol generating device (10) according to any one of the preceding claims, wherein said predetermined amount of aerosol is generated per user puff.

12. The aerosol generating device (10) according to any one of the preceding claims, wherein the control unit (14) is configured to power the aerosol generating unit (12) during the predetermined loading time further to detection of a user puff.

13. The aerosol generating device (10) according to any one of the preceding claims, wherein, outside the loading time, preferably after the loading time, the control unit (14) is configured to not power the aerosol generating unit (12) to generate aerosol.

14. The aerosol generating device (10) according to claims 12 and 13, wherein, outside the loading time, preferably after the loading time, the control unit (14) is configured to not power the aerosol generating unit (12) to generate aerosol until detection of a new user puff.

15. An operation method of an aerosol generating device (10) according to any one of the preceding claims, comprising powering an aerosol generating unit (12) during a predetermined loading time to generate a predetermined amount of aerosol.

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