Aerosol-forming device and system

Abstract

An aerosol-forming device (1) for forming aerosol from an aerosol-forming article is described, comprising a heating chamber (30) configured to receive at least a part of an aerosol-forming article; an upstream airflow path (40a) arranged upstream of the heating chamber (30) and in fluid communication with an external environment of the aerosol-forming device (1), such that air is drawable by a user in a user inhalation through the airflow path towards the heating chamber (30); a first heating device (6a) arranged at the heating chamber (30); a second heating device (70) arranged in thermal contact with the upstream airflow path (40a); a power source (15) for supplying the first heating device (6a) and the second heating device (70) with electrical energy, and control circuitry (5) configured to control the first heating device (6a) and the second heating device (70) based on controlling a supply of electrical power from the power source (15) to the first heating device (6a) and the second heating device (70), such that at an occurrence of a user inhalation, the power provided to the first heating device (6a) is reduced while the power provided to the second heating device (70) is increased.

Description

[0001] FTR4067

[0002] 1 / 80

[0003] AEROSOL-FORMING DEVICE AND SYSTEM

[0004] The present disclosure generally relates to the field of aerosol-forming devices and systems for generating aerosol, also referred to as aerosol-generating devices and aerosol-generating systems. In particular, the present disclosure relates to an electronic aerosol-forming device and an electronic aerosol-forming system configured to generate or form aerosol, for example aerosol inhalable by a user in one or more user inhalations or puffs. Further, the present disclosure relates to a method of controlling or operating an aerosol-forming device or system.

[0005] Aerosol-forming or aerosol-generating devices are typically designed as handheld devices that can be used by a user for consuming or experiencing, for instance in one or more usage sessions, aerosol generated from an aerosol-forming substrate or an aerosol-forming article. Therein, aerosol is typically generated by heating at least a part of the substrate to a certain temperature sufficient to release aerosol from the substate. The aerosol-forming devices the present disclosure pertains to are, in particular, directed to the field of heated tobacco products (HTP), heat-not-burn (HNB) devices, tobacco and tobacco-substitute products. However, the present disclosure may at least in some instances also be applicable to e-vapor devices, e-cigarettes, vaporizers, as well as other types of inhalers, dispensers, or atomizers, for example inhalers, dispensers, or atomizers for medical or pharmaceutical applications.

[0006] Typical aerosol-forming systems can be designed as one-part systems or devices including an aerosol-forming device that can be operated by a user to generate aerosol, for example from a removable or non-removable aerosol-forming article. Alternatively, aerosol-forming systems can be designed as two-part systems or devices comprising an aerosol-forming device and a companion device for storing and / or charging the aerosol-forming device. In either design or configuration, the aerosol-forming system or device can be used by a user for consuming or inhaling, for instance in one or more usage sessions, aerosol generated based on heating an aerosol-forming article or substrate couplable to or at least partly insertable into the aerosolforming system. In the context of the present disclosure, an aerosol-forming device can refer to both a one-part device and a two-part device, unless explicitly specified otherwise.

[0007] The aerosol-forming article, also referred to as aerosol-generating article, can comprise an aerosol-generating or aerosol-forming substrate. Generally, the aerosol-forming substrate may include a solid material, a liquid material or both liquid and solid material. Exemplary aerosolforming substrates can comprise solid substrate material with one or more ingredients, such as tobacco material, tobacco cast leaves (TCL) material or cannabis-based material.

[0008] The solid, liquid, or a mixed-form of solid and liquid aerosol-forming substrate may contain one or more ingredients, active ingredients or active agents, which may be vaporized during a usage session and inhaled by the user in one or more user inhalations. A user inhalation is synonymously and interchangeably used herein with “puff” of the user. Exemplary ingredients ofFTR4067

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[0010] the aerosol-forming article or substrate include nicotine, nicotine-containing substances, water, aroma, sugar, moisturising agent, botanicals, preservative, flavouring, for example cocoa, liquorice, menthol and lactic acid or other additives or ingredients. Other exemplary ingredients of the aerosol-forming substrate include one or more pharmaceutical agents, one or more drugs, one or more adjuvants or other active agents. Accordingly, the aerosol formed from a corresponding substrate may contain one or more of these ingredients, active ingredients or active agents and / or may be inhalable by the user in one or more user inhalations or puffs.

[0011] The aerosol-forming article may be configured in shape and size to be removably inserted at least partly into the aerosol-forming device or system. In some conventional systems or devices, the aerosol-forming article is usually formed as a stick that can be at least partly inserted into a heating volume, heating cavity or heating chamber of the aerosol-forming device for aerosol consumption. Alternatively or additionally, aerosol-forming substrates can comprise one or more liquids and / or solids, which can, for example, be supplied to the aerosol-forming device in the form of a cartridge, capsule or container. Corresponding exemplary aerosol-forming articles can comprise a cartridge containing or being fillable with the liquid and / or solid substrate, which can be vaporized during aerosol consumption by the user based on heating the substrate and / or liquid. Usually, such cartridge, capsule or container can be coupled to, attached to or at least partially inserted into the aerosol-forming device. Alternatively, the cartridge may be fixedly mounted to the aerosol-forming device and refilled by inserting liquid and / or solid into the cartridge.

[0012] For generating the aerosol during use or consumption, heat can be supplied by a heating element, heating device, heater arrangement or heat source to heat at least a portion or part of the aerosol-forming substrate. At least a part of the heating device can be arranged in the handheld device or a handheld part of the aerosol-forming device. Alternatively or additionally, at least a part of or the entire heating device can be fixedly associated with or arranged within an aerosol-forming article.

[0013] Exemplary heating elements, heating devices, or heater arrangements can be based on one or more of resistive heating, inductive heating, conductive heating, convective heating, infrared heating or other radiative heating, dielectric heating and microwave heating using electrical energy supplied via, drawn from or stored in an energy storage or battery of the aerosolforming device.

[0014] Typically, aerosol-forming devices comprise an energy storage or power source, for example a rechargeable energy storage, providing the electrical energy needed to operate the aerosol-forming device and especially for heating the aerosol-forming substrate and / or article, for example to generate aerosol in one or more usage sessions using one or more aerosol-forming articles.FTR4067

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[0016] To actually store electrical energy, the energy storage may include one or more battery cells, one or more rechargeable battery cells, one or more accumulators, one or more capacitors or one or more other devices or components for storing electrical energy. Exemplary energy storages may include a plurality of rechargeable battery cells, such as for example between two and ten, preferably between two and four battery cells. Further, exemplary re-chargeable battery cells may be based on lithium-ion battery cells. For example, a cathode material may comprise lithium-cobalt-oxide (LCO), lithium-manganese-oxide (LMO), lithium-nickel-manganese-cobalt-oxide (NMC or NCM), lithium-iron-phosphate (LFP), and / or lithium-nickel-cobalt-aluminum-oxide (NCA). Alternatively or additionally, an anode material may comprise carbon (e.g. graphite), silicon and / or lithium-titanate-oxide (LTO).

[0017] Some conventional aerosol-forming devices or systems utilize a plurality of heating devices that may be arranged in an aerosol-forming device to heat the aerosol-forming article or substrate for aerosol consumption. In these conventional systems, usually, all heating devices are powered by a power source or energy storage irrespective of from one another, which can lead to sub-optimal usage of energy or power resources at the aerosol-forming device or system.

[0018] Therefore, it may be desirable to provide for an improved aerosol-forming device, system and corresponding method, which at least partly mitigates or overcomes the drawbacks of conventional systems and devices. In particular, the aerosol-forming device, system and method described herein may enable an improved, advanced or sophisticated power management.

[0019] These advantages may be achieved by the features described herein.

[0020] Aspects of the present disclosure relate to an aerosol-forming device, an aerosol-forming system, and to a method of operating or controlling an aerosol-forming device or system. It is noted that any disclosure presented herein with reference to an or one aspect of the present disclosure, equally applies to any other aspect of the present disclosure, unless explicitly stated otherwise. In particular, it is emphasized that any disclosure presented herein with respect to an aerosol-forming device equally applies to an aerosol-forming system comprising such aerosolforming device and optionally a charger case or companion device, and vice versa.

[0021] According to an aspect, there is provided an aerosol-forming device, also referred to herein as aerosol-generating device, for forming aerosol from an aerosol-forming substrate or article. The aerosol-forming device comprises a heating chamber configured to receive at least a part of an aerosol-forming article. The aerosol-forming device further comprises an upstream airflow path arranged upstream of the heating chamber and in fluid communication with an external environment of the aerosol-forming device, such that air is drawable by a user in a user inhalation through the airflow path towards the heating chamber. The aerosol-forming device further comprises a first heating device arranged at the heating chamber, and a second heating device arranged in thermal contact with the upstream airflow path. Further, the aerosol-forming deviceFTR4067

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[0023] comprises a power source, also referred to herein as energy storage, for supplying the first heating device and the second heating device with electrical energy, for example to heat the aerosol-forming substrate to generate inhalable aerosol. The aerosol-forming device further comprises a control circuitry configured to control the first heating device and the second heating device based on controlling a supply of electrical power from the power source to the first heating device and the second heating device, such that at an occurrence of a user inhalation, the electrical power provided or supplied to the first heating device is reduced or decreased while the electrical power provided or supplied to the second heating device is increased.

[0024] Accordingly, the control circuitry can be configured to operate, control and / or operatively control the first heating device and the second heating device in a coordinated manner at least during occurrence of a user inhalation or puff at the aerosol-forming device. As a consequence, the electrical power or energy provided by the power source can be utilized in an optimized and energy efficient manner. In particular, thermal and / or electrical losses can be reduced or minimized, thereby allowing to use a larger portion of the available electrical power to heat the substrate at a given time during occurrence of the user inhalation, when compared to powering the first and second heating devices in non-coordinated manner. Hence, power management can improved by the aerosol-forming system described herein. It is noted that any reference to a “power” herein, refers to an electrical power.

[0025] Also, the power source of the aerosol-forming device may be operated safely up to a particular power or energy drawn from the power source per unit time. Exceeding this particular power or energy drawable safely from the power source per unit time, may lead to excessive strain of the power source and increase degradation thereof. Therefore, operating the first heating device and the second heating device in a coordinated manner, as described herein, can allow reducing or avoiding excessive strain on the power source, reduce degradation thereof and can extend the lifetime of the power source.

[0026] As used herein, reducing the power to, supplied to or provided to the first heating device and increasing the power to, supplied to or provided to the second heating device “at the occurrence of a user inhalation” can mean or include reducing or increasing the power to the respective heating device at the time where a user inhalation occurs. This can include reducing or increasing the power to the respective heating device at the instant or point in time the user inhalation starts, which can be synonymously used herein with “start, onset or initiation of the user inhalation”. Alternatively or additionally, this can include reducing or increasing the power to the respective heating device during at least a part of a duration, optionally the entire duration, of a user inhalation or puff. Also, any increase or decrease in power or electrical power described herein can be a gradual, continuous or step-wise increase or decrease.FTR4067

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[0028] Further, it is noted that a power delivery or supply of electrical power from the power source to one of or both the first heating device and the second heating device can be a continuous power delivery or supply, or can be a pulsed delivery or supply of electrical power. In other words, the first and / or second heating device may be operated by the control circuitry based on continuous power supply or based on pulsed power supply. In particular for pulsed power delivery or supply, a reduction in the power may mean or include a reduction of a duty cycle ratio. For instance, reducing or increasing the power to the first / second heating device can include reducing or increasing the duty cycle ratio for the first / second heating device. A reduction in the power to the first or second heating device may mean, for example, that during a given time interval, the first or second heating device can receive pulsed energy with a duty cycle ratio of 75%, and when the power delivery is reduced, the duty cycle ratio can decrease or go down, for example to 25%. However, the pulses could still have the same width, but there may be fewer pulses, to reduce the average power that is delivered to the first or second heating device. Alternatively or additionally, an increase in the power to the first or second heating device may mean, for example, that during a given time interval, the first or second heating device can receive pulsed energy with a duty cycle ratio of 25%, and when the power delivery is increased, the duty cycle ratio can increase, for example to 75%. Also in this case, the pulses could still have the same width, but there may be more pulses, to increase the average power that is delivered to the first or second heating device. Also, pulse width modulation may be used to change the duty cycle ratio of any of the first and second heating devices.

[0029] The aerosol-forming device the present disclosure pertains to may, for example, refer to a handheld, battery-powered, lightweight and / or portable device. However, the present disclosure is not limited in this respect, but can be implemented in various forms and designs of aerosolforming devices and systems.

[0030] In the context of the present disclosure, the aerosol-forming device and / or the aerosolforming system may be a portable device and / or system. It may be battery powered. Particularly, the aerosol-forming device and / or the aerosol-forming system may be pocket-size, hand-held, suitable for one-hand use and / or may weigh less than 300 g, preferably less than 200 g. It may be shaped and / or sized to fit snugly into a user’s hand. It may be carried in jacket and / or trouser pockets. Particularly, the aerosol-forming device and / or the aerosol-forming system may be configured to provide aerosol for human inhalation and / or human consumption, particularly inhalation and / or consumption through the mouth.

[0031] As used herein, the term “usage session” may, generally, refer to a period of time, during which a user may use the aerosol-forming device to generate, consume, experience or inhale aerosol. In a single usage session, an aerosol-forming article may be consumed by the user completely or partly. Also, a plurality of aerosol-forming articles may be consumed by the user inFTR4067

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[0033] a single usage session. Further, the user may take one or more puffs or user inhalations during a usage session. Generally, a usage session may be finite in time. In otherwords, a usage session may have a start, an end and a duration. The duration of the usage session as measured by time may be influenced by use during the usage session. Optionally, the duration of the usage session, for example monitored by a control circuitry of the aerosol-forming device, may have a maximum duration determined by a maximum time from the start of the usage session. The duration of the usage session may be less than the maximum time if one or more monitored parameters reach a predetermined threshold before the maximum time from the start of the usage session. By way of example, the one or more monitored parameters may comprise one or more of: i) a cumulative puff count of a series of puffs drawn by a user since the start of the usage session, and ii) a cumulative volume of aerosol evolved from the aerosol-forming substrate since the start of the usage session. Other parameters can be used instead or in addition.

[0034] As used herein, the terms "upstream" and "downstream" may describe the relative positions of components or elements of the aerosol-forming device or system in relation to the direction of the airflow through the heating chamber and / or the aerosol-generating article towards the mouth of the user for inhalation. The airflow through the aerosol-forming article may refer to the flow through the article, when placed or situated in the aerosol-generating device. The airflow through the heating chamber and / or aerosol-forming article that is caused by a user inhalation may be substantially directed along a longitudinal axis of the aerosol-forming device and / or article.

[0035] As used herein, “upstream” may refer to a location that comes before a particular point of reference in the direction of the airflow. Unless specified otherwise, the reference point or location is the heating chamber and / or aerosol-forming article, when placed or situated in the heating chamber. For example, an upstream part or element of the device may refer to a part or element where the air comes from before reaching the heating chamber and / or aerosol-forming article. Accordingly, the upstream airflow path refers to an airflow path where the air comes from before reaching the heating chamber and / or aerosol-forming article.

[0036] As used herein, “downstream” may refer to a location that comes after a particular point of reference in the direction of the airflow, in particular after the heating chamber and / or aerosolforming article. For example, a downstream part or element of the device may refer to a part or element where the air goes or flows to after leaving the reference point, in particular the heating chamber and / or article.

[0037] The upstream airflow path can be in fluid communication with the external environment or a surrounding of the aerosol-forming device. This may mean that the upstream airflow path is fluidly coupled or connected to the surrounding or external environment of the device. The airflow through the upstream airflow path may also be referred to herein as upstream airflow. UnlessFTR4067

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[0039] explicitly stated otherwise in the following, a reference to an airflow path or the airflow path, refers to the upstream airflow path.

[0040] For example, the upstream airflow path may be fluidly coupled to the external environment via one or more air inlets, also referred to herein as main air inlets or device inlets. Optionally, the upstream airflow path and the one or more air inlets may be fluidly interconnected by one or more airflow path structures or elements configured to guide or convey the air from the one or more air inlets towards or to the upstream airflow path. The one or more airflow path structures or elements may, for example, be defined by one or more walls or components arranged in a housing or device body of the aerosol-forming device.

[0041] The second heating device being arranged in thermal contact with the upstream airflow path may mean or include that at least a part of the second heating device is thermally coupled to the upstream airflow path, such that heat or thermal energy can be exchanged between a heatexchange element of the second heating device and the upstream airflow path or the airflow through the upstream airflow path. For example, at least a part of the second heating device may be arranged in or protrude into the upstream airflow path to form a heat-exchange element, such that air can pass along at least a part of the surface of heat-exchange element the second heating device. Alternatively or additionally, the second heating device may exchange heat or thermal energy with the air in the upstream airflow path via at least one thermally conductive element.

[0042] The first heating device can be configured to perform a first heating operation, and the second heating device can be configured to perform a second heating operation different than the first heating operation. Accordingly, the control circuitry can be configured to control the second heating device to perform the second heating operation and / or to control the first heating device to perform the first heating operation. Accordingly, the first heating operation performed by the first heating device can differ from the second heating operation performed by the second heating device. This may allow for precise temperature control, which can be beneficial in terms of taste and user experience. Also, at least in some instances, more energy efficient and / or more rapid heating may be provided when using two heating devices that are configured to perform different heating operations rather than using heating devices that perform the same heating operation.

[0043] In an example, the second heating device may be configured to perform a puff-on-demand heating operation, also referred to as response-to-draw heating operation. Alternatively or additionally, the control circuitry can be configured to control the second heating device to perform a puff-on-demand heating operation. Accordingly, the second heating operation may be or include a puff-on-demand heating operation.

[0044] For example, the second heating operation can include or refer to a puff-on-demand heating operation, such that the second heating device is operated or heated in correspondence with theFTR4067

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[0046] occurrence of a user inhalation at the aerosol-forming device. In other words, the control circuitry can be configured to control the second heating device to perform a puff-on-demand heating operation, such that the second heating device is operated in correspondence with the occurrence of a user inhalation at the aerosol-forming device. Alternatively or additionally, the second heating device may be configured to perform a puff-on-demand heating operation.

[0047] For example, the control circuitry can be configured to regulate or control a supply of electrical power from the power source to the second heating device in accordance or correspondence with the occurrence of one or more user inhalations taken or performed by the user. In particular more power or a higher power level, for example higher voltage and / or current, may be supplied to the second heating device during a puff or user inhalation compared to times when no user inhalation occurs. Optionally, the second heating device may only be supplied with electrical power during a user inhalation, and / or no electrical power may be supplied at other times. Generally, puff-on-demand heating of the second heating device can reduce energy consumption and allow operation of the aerosol-forming device in an energy efficient manner.

[0048] In the context of the present disclosure, a "puff-on-demand" heating operation may refer to a method of controlling the second heating device based on or in accordance with a user inhalation or puff being performed or occurring. For instance, the second heating device may be activated only during at least a part of the user inhalation or only powered at a power level sufficient to generate aerosol during at least a part of the user inhalation, rather than being continuously heated throughout an entire usage session. Puff-on-demand heating can be designed to optimize energy efficiency and, for example, enhance user experience by providing aerosol only when needed, thereby reducing unnecessary heating and potential degradation of the aerosol-forming substrate. A puff-on-demand heating operation of the aerosol-forming device, as used herein, may include or refer to operation of the aerosol-forming device, respectively, the second heating device, according to a puff-on-demand heating scheme. Further, it is noted that the terms puff and user inhalation are synonymously and interchangeably used herein.

[0049] The first heating device can be configured to perform a continuous heating operation during a usage session. In other words, the first heating device can be configured to continuously heat the aerosol-forming article or substrate during the usage session. Alternatively or additionally, the control circuitry can be configured to control the first heating device to perform a continuous heating operation during a usage session. Accordingly, the first heating operation may be or include a continuous heating operation. For example, the first heating device may be continuously powered by the power source or may be continuously supplied with electrical power during the usage session.

[0050] It is emphasized that “continuous heating”, as used herein, is to be construed broadly and may mean that the temperature of the first heating device is kept at a value above room or ambientFTR4067

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[0052] temperature throughout the usage session. This does not exclude that the power to first heating is at least temporarily reduced or cut completely during a usage session, for example during at least a part of a user inhalation. Also, continuous heating may include heating the first heating device with pulses of voltage and / or current having a comparatively high repetition or pulse frequency, for example a pulse repetition in the range of deciseconds, milliseconds, microseconds or even higher. For example, continuous heating may include heating based on pulse width modulation, bang-bang or hysteresis control mode, sliding control mode, or other type of on-off control mode.

[0053] The second heating device can be configured to perform a second heating operation to heat or indirectly heat the substrate based on heating the airflow in the upstream airflow path. This may mean that the second heating operation can involve or include indirect heating of the substrate via the airflow through the upstream airflow path, for example departed by one or more user inhalations during a usage session. As used herein, “indirect heating of the substrate” may mean that heating is performed in absence of or without a physical contact between the second heating device and the aerosol-forming article. Accordingly, the second hearting device may be configured to heat the aerosol-forming substrate without contacting the aerosol-forming article or substrate.

[0054] In an example, the second heating device may be configured to heat or indirectly heat at least a part of the substrate by convective heating. For instance, the second heating device may include a resistive heating element configured to heat air in the upstream airflow path to at least heat a part of the substrate of the aerosol-forming article by convective heating.

[0055] As used herein, convective heating can relate to heat transfer from a heating device, in particular the second heating device, that involves the movement of hot air or gas to heat the aerosol-forming substrate or article. For instance, the second heating device can be configured to be resistively heated and to heat the air around, for example flowing past, the second heating device or at least a part thereof. The heated air may then be conveyed or guided through the upstream airflow path towards the heating chamber, where the aerosol-forming article or substrate may be situated. Hence, the aerosol-forming substrate or article can be indirectly heated by the flow of hot or heated air generated by the second heating device. The airflow for efficiently heating the aerosol-forming article or substrate may be provided or driven by the actual user inhalation or puff. Unless specified otherwise, indirect heating of the substrate and heating of the substrate by convection may be interchangeably used herein.

[0056] The first heating device may be configured to perform a first heating operation to heat or directly heat the substrate. This may mean that the first heating operation can involve or include direct heating of the aerosol-forming substrate. As used herein “direct heating of the substrate” may mean that at least a part of the first heating device can be in physical or direct contact withFTR4067

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[0058] at least a part of the aerosol-forming article, for example one or more surfaces or main faces thereof. Accordingly, the first heating device can be arranged and configured to contact at least a part of the aerosol-forming article, for example thereby enabling direct heat transfer from at least a part of the first heating device to the aerosol-forming article. It is emphasized that “direct heating of the substrate”, as used herein, does not necessarily involve a physical contact of the first heating device with the substrate, which may for example be arranged within the aerosol-forming article, so that the first heating device can only contact the aerosol-forming article at one or more surfaces, for example one or more main faces of the article.

[0059] The first heating device may be configured to heat at least a part of the substrate of the aerosol-forming article by conductive heating. For example, the first heating device may comprise one or more heating elements that may be configured to heat the substrate or article by conduction. Generally, conductive heating can be advantageous in terms of providing rapid and efficient heat transfer, which can lead to quick vaporization of substrate material.

[0060] As used herein, heating by conduction may involve or include a direct transfer of heat or thermal energy from the first heating device or one or more heating elements thereof to the aerosol-forming article or substrate. For example, at least a part of the first heating device, and / or at least one heating element thereof may be configured or arranged to contact or directly contact the aerosol-forming article to heat or directly heat the article or substrate.

[0061] In an example, the first heating device may comprise two opposing heating elements comprising electrically conductive material and being configured to be resistively heated. Optionally, the two opposing heating elements may be part of a resistive heating device of the first heating device. Accordingly, the heating elements of the first heating device may be resistive heating elements, also referred to as Joule-type heating elements.

[0062] As used herein, “resistive heating” means that the electrical resistance of the respective component is used to generate heat or thermal energy. Specifically, when applying electrical power to an electrically conductive element, at least a part of the electrical energy is converted to thermal energy or heat due to the electric losses in the material. This effect can be used to heatup at least a part of the heating elements of the heating device to increase their temperature and heat the substrate. Further, the resistively generated heat can at least partly be transferred to the aerosol-forming article or substrate based on conduction.

[0063] Alternatively, the two opposing heating elements of the first heating device may each include a susceptor configured to be inductively heated. For example, the first heating device may comprise one or more heating coils configured to heat the heating elements based on or by induction.

[0064] For inductive heating, an alternating magnetic field may be generated by the one or more heating coils. The heating elements and / or susceptors may be at least partly arranged in theFTR4067

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[0066] alternating filed, such that eddy currents can be induced in the susceptors of the heating elements, which are at least partly converted to heat in the susceptor material, thereby heating the heating elements.

[0067] Also, a combination of resistive and inductive heating elements may be used or included in the first heating device. For example, one heating element may be heated resistively and the other one may be heated by induction. Further optionally, the first heating device may include one or more further heating elements, for example, configured to heat one or more lateral side faces of the aerosol-forming article. The heating elements heating the main faces and the one or more further heating elements heating the lateral side faces of the aerosol-forming article can employ different heating technologies. For instance, the heating elements may be resistive heating elements and the one or more further heating elements may be heated inductively, or vice versa.

[0068] The heating chamber, as used herein, may generally refer to a space or volume within the aerosol-forming device that is configured to at least partly receive or accommodate the aerosolforming article in order to heat it during a usage session. The heating chamber may also be referred to herein as or may comprise a heating volume of the aerosol-forming device. At least a part of the first heating device may define at least a part of the heating chamber. For example, the first heating device may comprise at least two opposing and spaced-apart heating elements which define the heating chamber and / or heating volume, for example as the space between the opposing heating elements.

[0069] The control circuitry, as used herein, may refer to a control means for controlling operation of the first heating device, the second heating device, optionally a power source or energy storage of the device, and further optionally one or more other functions of the aerosol-forming device. The control circuitry may include one or more processors, for example a microcontroller unit (MCU), and / or one or more other data processors. The control circuitry may generally be configured to execute programmed instructions, for example stored in a data storage or memory of the device, to manage the heating process of an aerosol-forming substrate or article based on controlling the first heating device, controlling the second heating device, controlling power supply to one or both the first heating device and the second heating device, and / or controlling the power source or energy storage of the aerosol-forming device. The control circuitry may be implemented partly in software and partly in hardware. At least a part of the control circuitry and / or at least a part of its functionalities may be implemented as Application-Specific Integrated Circuit (ASIC), on a printed circuit board with one or more discrete components, as a microcontroller-based implementation, as Field-Programmable Gate Array (FPGA), or hybrid implementation using a combination thereof.

[0070] The aerosol-forming device may comprise a power source or energy storage, for example to provide the electrical power or energy to operate one or both the first heating device and theFTR4067

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[0072] second heating device. The “power source” may also be referred to herein as energy storage of the aerosol-forming device or system. The energy storage or power source may be a rechargeable energy storage, providing the electrical energy needed to operate the aerosolforming device and especially for heating the aerosol-forming substrate and / or article, for example to generate aerosol in one or more usage sessions using one or more aerosol-forming articles. As mentioned above, to actually store electrical energy, the energy storage may include one or more battery cells, one or more rechargeable battery cells, one or more accumulators, one or more capacitors, such as supercapacitors or, one or more other devices or components for storing electrical energy.

[0073] The power source of the aerosol-forming device may be configured to provide the electrical power to operate the first heating device and the second heating device. In other words, the power source may be a common power source configured to power both the first heating device and the second heating device. In an example, the aerosol-forming device may comprise a single power source for powering the first and second heating device. Using a common power source for both heating devices can allow increasing the storage capacity for both heating devices and can safe space. Also, flexibility in terms of at which heating device to use the electrical power can be enhanced. Also, advanced power or energy management can be implemented, for example allowing to use the electrical power at the heating device, which can utilize the power most efficiently among the first and second heating devices. Optionally, however, the aerosol-forming device may include a plurality of power sources.

[0074] It should be noted that controlling the second heating device and / or controlling the first heating device can include controlling the power supply, power source or energy storage of the aerosol-forming device. Accordingly, the control circuitry can be configured to control the first and / or second heating device based on controlling the power source, respectively, based on controlling a power supply from the power source to the first heating device and / or the second heating device. Accordingly, and reference herein to controlling the first or second heating device can include a respective control of the power source.

[0075] The term power or electrical power provided to one or both the first and second heating devices, as used herein, may refer to the amount of electric energy provided to, supplied to, drawn by and / or consumed by the respective one or both the first heating device and the second heating device per unit time. As commonly used, the power or electrical power can, for example, be measured in watts and / or be representative or indicative of the rate at which electrical energy is converted, for example into heat or thermal energy within the material of one of or both the first heating device and the second heating device. Further, it is noted that a power level, as used herein, can refer to the amount of electrical energy provided to or drawn by a component of the aerosol-forming device per unit time, such as the first heating device or second heating device.FTR4067

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[0077] Accordingly, a power level can refer to or include a value of the power delivered to or consumed by the respective component.

[0078] Further, it should be noted that an increase in power or power level supplied to one or both the first heating device and the second heating device can be accompanied by or cause an increase in the temperature of the respective one of or both the first heating device and the second heating device. Vice versa, a decrease or reduction in power or power level supplied to one or both the first heating device and the second heating device can be accompanied by or cause a decrease or reduction in the temperature of the respective one of or both the first heating device and the second heating device.

[0079] An average duration of a typical user inhalation may be in the range from about 500 ms to about 5 seconds, for example from about 1.5 seconds to about 3.5 seconds. At the start, initiation, onset or occurrence of the user inhalation, the control circuitry may be configured to reduce the electrical power provided to the first heating device and increase the electrical power provided to the second heating device. For example, the power to the first heating device may be reduced gradually or step-wise within a period of time of about 0.5 ms (milliseconds) to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms. Optionally, the power to the first heating device may be reduced as fast as possible at the start or upon detecting start of the user inhalation. Alternatively or additionally, the power to the second heating device may be increased gradually or step-wise within a period of time of about 0.5 ms to about 1 second, for example about 0.5 ms to about 500 ms, in particular about 0.5 to about 200 ms for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms. Optionally, the power to the second heating device may be increased as fast as possible at the start or upon detecting start of the user inhalation.

[0080] The control circuitry can be configured to detect the occurrence of the user inhalation and / or the start of the user inhalation, to reduce or decrease the power provided to the first heating device in response to detecting the occurrence or start of the user inhalation, and to increase the power provided to the second heating device in response to detecting the occurrence or start of the user inhalation. In other words, the control circuitry may be configured to reduce or decrease the power supplied to the first heating device, and to increase the power supplied to the second heating device upon, for example immediately upon, determining or detecting occurrence and / or start of the user inhalation at the aerosol-forming device. Accordingly, detection of the user inhalation, respectively start, onset and / or occurrence thereof, can trigger the increase in the electrical power supplied to the second heating device and can trigger the decrease in the electrical power supplied to the first heating device. Increasing the power to the second heating device can allow to efficiently heat the airflow through the upstream airflow path at the time where fresh air is drawn into the device by the user inhalation. Further, reducing the power to the firstFTR4067

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[0082] heating device can allow delivering more power to the second heating device at the start of the user inhalation, thereby further increasing the heating effect departed by the second heating device to the upstream airflow path and hence also to the substrate. Also, the second heating device may have a lower thermal mass than the first heating device, such that a higher temperature increase can be provided for a given amount of electrical energy consumed within a given time period. Hence, the consumed energy can be efficiently used to heat the aerosolforming substrate.

[0083] The aerosol-forming device may, in an example, comprise a puff sensor configured to detect a user inhalation at the aerosol-forming device. Alternatively or additionally, the control circuitry may be configured to detect a user inhalation, for example start, occurrence or termination thereof, based on a puff sensor. Exemplary puff sensors can include one or more pressure sensors, one or more acoustic sensors, one or more flow sensors, one or more capacitive sensors and one or more accelerometer-based sensors.

[0084] In yet a further example, the control circuitry may be configured to determine a user inhalation at the aerosol-forming device based on determining a change in a temperature of at least one of the first heating device and the second heating device caused by a change in the airflow through the upstream airflow path resulting from the user inhalation, and for example by a cooling effect departed by the airflow onto the one or both the first and second heating devices.

[0085] Accordingly, the aerosol-forming device, respectively, the control circuitry thereof can detect or determine a temperature change caused by the change in the airflow through the upstream airflow path that is induced by or results from the user inhalation or puff taken by the user. For example, if the user inhales, air or fresh air may be drawn from the external environment into the upstream airflow path, such that an airflow, also referred to as upstream airflow, is generated in the upstream airflow path. The fresh air drawn from the external environment may substantially have room or ambient temperature, and hence can depart a cooling effect onto the first heating device and / or second heating device. Therefore, the change in temperature, which in this example is a decrease in temperature, can be indicative of the user inhalation, of a start of the user inhalation and / or of occurrence of the user inhalation at the aerosol-forming device. Hence, by determining the change in temperature of one of or both the first heating device and second heating device, the control circuitry can gain information about or can be enabled to detect the user inhalation at the aerosol-forming device. Moreover, if the user stops inhaling, the airflow through the upstream airflow path stops or is at least reduced, which can cause a further change in the temperature of one of or both the first heating device and the second heating device. Specifically, termination or stop of the user inhalation can lead to or cause an increase in temperature of one of or both the first heating device and the second heating device, which canFTR4067

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[0087] be determined or detected by the control circuitry. Thereby, the control circuitry can be enabled to detect or determine termination or stop of the user inhalation at the aerosol-forming device.

[0088] Hence, based on determining one or more changes in the temperature of one of or both the first heating device and the second heating device, the control circuitry can be enabled or configured to detect one or more of start, an onset, occurrence, termination and duration of a user inhalation or puff. In turn, this can allow for an operational control of one or more of the first heating device, the second heating device and the power source or energy source in accordance or correspondence with the one or more detected changes in the temperature of one or both the first heating device and the second heating device.

[0089] The control circuitry may be configured to determine or detect one or more of the user inhalation, occurrence of the user inhalation, a duration of the user inhalation, an onset of the user inhalation, and a start of the user inhalation at the aerosol-generating device based on determining or detecting a change or decrease in the temperature of at least one of the first heating device and the second heating device.

[0090] Alternatively or additionally, a change in temperature, in particular an increase in temperature, of one or both the first heating device and the second heating device may occur when the user stops inhaling, respectively when the user inhalation is terminated or ended. Accordingly, the control circuitry can be configured to determine or detect one or more of the user inhalation, termination of the user inhalation, an end of the user inhalation and a duration of the user inhalation based on determining or detecting a change or an increase in the temperature of one of or both the first heating device and the second heating device.

[0091] Accordingly, the control circuitry can be configured to detect or determine a user inhalation at the aerosol-forming device based on one of or both detecting a decrease in the temperature and an increase in the temperature of one of or both the first heating device and the second heating device. Hence, the control circuitry can provide the functionality of a puff sensor based on determining changes in the temperature of the first heating device and / or the second heating device.

[0092] At least in some configurations or designs, the second heating device may have a lower thermal mass compared to the first heating device. This can be particularly true in case the second heating device is designed or configured as convective heater that can heat the aerosol-forming article or substrate by convective heating. Due to the lower thermal mass, the temperature of the second heating device may adapt more quickly to the temperature of the air surrounding or flowing past the second heating device, when compared to the first heating device. Hence, a response time for detecting an actual change in the temperature of the second heating device, and hence a response time for detecting the user inhalation, can be reduced by using the second heating device compared to relying on the first heating device, at least in certain designs andFTR4067

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[0094] configurations of the two heating devices. Hence, utilizing the second heating device as temperature sensor and / or as puff detection sensor, can allow for a fast and precise control of the aerosol-forming device.

[0095] The control circuitry can further be configured to determine the temperature of the first heating device and / or one or more heating elements thereof based on determining an electrical resistance of the first heating device. Alternatively or additionally, the control circuitry can further be configured to determine the temperature of the second heating device based on determining an electrical resistance of the second heating device. Optionally, the control circuitry can be configured to regulate or control the temperature of the one of or both the first heating device and the second heating device based on determining or measuring the electrical resistance of the respective one of or both the first heating device and the second heating device. Generally, utilizing the electrical resistance to determine the temperature may allow for a precise and reliable determination of the temperature without requiring a dedicated temperature sensor. Optionally, however, one or more temperature sensors may be used instead of or in addition to measuring the electrical resistance.

[0096] It should be noted that any reference to a “resistance” of the first and / or second heating device in the following, relates to the electrical resistance, unless explicitly stated otherwise.

[0097] Also, any reference to or disclosure related to a determination or measurement of a temperature of one of or both the first heating device and the second heating device can include a determination or measurement of the electrical resistance of the respective one of or both the first heating device and the second heating, and vice versa.

[0098] In an example, the control circuitry may be configured to monitor or determine the electrical resistance of the first and / or second heating device during the usage session and / or during a user inhalation. Therein monitoring the resistance may include determining the electrical resistance with a predetermined repetition or sampling frequency, for example in the Hertz to Kilohertz or even Megahertz range.

[0099] For certain materials, the electrical resistance depends on the temperature of the material, which particularly applies to electrically conductive materials that show an increase in the electrical resistance with increasing temperature. Therefore, the temperature of one of or both the first heating device and the second heating device can be precisely and reliably determined based on determining or measuring the electrical resistance thereof. Similarly, also changes in the temperature of one of or both the first heating device and the second heating device can be reliably and precisely determined based on determining changes in the electrical resistance of the respective component.

[0100] For example, the electrical resistance of one of or both the first heating device and the second heating device can be measured or determined by the control circuitry by or based onFTR4067

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[0102] one or more of determining a voltage across or supplied to one of or both the first heating device and the second heating device, determining a current across or supplied to one of or both the first heating device and the second heating device, and determining a voltage drop across a shunt resistor coupled to one of or both the first heating device and the second heating device.

[0103] In an example, the first heating device may comprise two opposing heating elements that may be connected in series, and the control circuitry may be configured to regulate or control the temperature of one or both heating elements based on determining the total electrical resistance of both heating elements. Determining the total resistance rather than individual resistance values for each heating element may reduce complexity of the control circuitry.

[0104] The control circuitry can further be configured to regulate or control the temperature of the heating elements based on determining an electrical resistance of the heating elements, for example total resistance of both heating elements, and based on one or more predetermined calibration values associating the electrical resistance with a temperature of the heating elements.

[0105] Optionally, one or more conversion or calibration values for computing one or more temperature values based on determined one or more resistance values of one of or both the first heating device and the second heating device may be stored in a data storage or memory of the aerosol-forming device, for example in the form of a look-up table, correlation table, correspondence table or matrix. The control circuitry may access or process the one or more conversion or calibration values to compute temperature values based on determined resistance values. Alternatively or additionally, one or more conversion or calibration values for computing one or more resistance values based on determined one or more temperature values may be stored in a data storage or memory of the aerosol-forming device, for example in the form of a look-up table, conversion table or matrix. The control circuitry may access or process the one or more conversion or calibration values to compute resistance values based on determined temperature values.

[0106] The control circuitry can be configured to increase the power to the second heating device and reduce the power to the first heating device upon detecting one or more start, initiation, onset and occurrence of a user inhalation at the aerosol-forming device. Therein, the control circuitry can be configured to simultaneously or concurrently reduce the power provided to the first heating device and increase the power provided to the second heating device. In other words, the power to the first heating device may be reduced and the power to the second heating device may be increased at the same, substantially same or at least overlapping times. Hence, the supply of power can be shifted from the first heating device to the second heating device, thereby ensuring that the second heating device can be powered at a considerably high power level, for example a nominal power level of the power source, for example which can allow rapid heating of the second heating device, the airflow through the airflow path, and hence the aerosol-formingFTR4067

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[0108] substrate. Therefore, the electrical energy can be efficiently used or consumed to heat the substrate.

[0109] The control circuitry can further be configured to reduce or decrease the power provided to the first heating device at the occurrence, start, onset or initiation of the user inhalation to a power level below a power level of the power supplied to the first heating device before the occurrence or start of the puff, for example an instant in time directly preceding the start of the user inhalation. Alternatively or additionally, the control circuitry can be configured to deactivate or stop the supply of electrical power to the first heating device at the occurrence, start, onset or initiation of the user inhalation. Also a combination of the forementioned options is possible. For example, the power level may be reduced at the occurrence of some user inhalations during a usage session, while the power supply may be deactivated or stopped at the occurrence of one or more other user inhalations during the same usage session. Accordingly, power consumption by the first heating device may be reduced or stopped completely at the occurrence or start of one or more user inhalations during a usage session, thereby allowing to provide more power to the second heating device and / or to use the available electrical power in an efficient way.

[0110] In an example, the control circuitry can be configured to reduce the power level to or deactivate the first heating device, for example gradually or step-wise, within a period of time of about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms, from the start of the user inhalation, respectively from the instant in time of detecting the start of the user inhalation.

[0111] As used herein, “at the occurrence, start, onset or initiation of the user inhalation” may refer to the instant in time the user inhalation is started, initiated and / or occurs. Alternatively or additionally, it may refer to the instant in time, the user inhalation, respectively, its start, onset, initiation or occurrence is detected by the control circuitry or aerosol-forming device.

[0112] The control circuitry can further be configured to increase the power provided to the second heating device at the occurrence, start, onset or initiation of the user inhalation from an initial power level to a nominal power level during the occurrence of the user inhalation. This way, the cooling effect departed by the airflow through the airflow path can be compensated by the increase in power supplied to the second heating device, and hence the associated increase in temperature of the second heating device.

[0113] In an example, the control circuitry can be configured to activate the second heating device or increase the power to the second heating device from the initial power level to the nominal power level, for example gradually or step-wise, within a period of time of about 0.5 ms to about 1 second, for example about 0.5 ms to about 500 ms, in particular about 0.5 to about 200 ms for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms, from theFTR4067

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[0115] start of the user inhalation, respectively from the instant in time of detecting the start of the user inhalation.

[0116] For example, when increasing the temperature of the second heating device upon detecting a user inhalation, the temperature of the second heating device and / or substrate can increase about 100°C within about 0.05 to 1 seconds, for example about 100°C within about 0.05 to 0.5 seconds, or for example about 100°C within 0.075 to 0.25 seconds, preferably about 100°C within about 0.1 to 0.2 seconds. In an example, the temperature of the second heating device may increase from ambient temperature to about 300°C within about 100 ms and / or to about 500°C within about 700 ms.

[0117] A target temperature of the second heating device, to which it may be heated during occurrence of a user inhalation, may be in a range from about 270°C to about 500°C, for example from about 270°C to about 450°C, or for example from about 270°C to about 320°C, in particular from about 280°C to about 310°C, preferably about 300°C. These temperature ranges have been found to lead to rapid heating of the substrate at minimum risk for overheating.

[0118] The initial power level may refer to or denote the level of electrical power supplied by the power source to the second heating device (or first heating device) at an instant in time preceding or directly preceding the occurrence, start, onset or initiation of the user inhalation. Alternatively or additionally, the initial power level may refer to or denote the level of electrical power supplied by the power source to the second heating device (or first heating device) at the instant in time of the the occurrence, start, onset or initiation of the user inhalation. The initial power level may be zero Watts, which may mean that respective second or first heating device may not be powered or may be deactivated, when powered at the initial power level.

[0119] The “nominal power level” is to be construed broadly and may, generally, refer to a predefined or predetermined power level that the power source is configured, designated or designed to provide. Optionally, the nominal power level may refer to a maximum or specified power level suppliable by or drawable from the power source, for example at a given charging state of the power source. The nominal power level may refer to a predefined, designated or rated power output of the power source, which the power source can provide to operate optimally. It should be noted that the nominal power level can optionally refer to a nominal power level suppliable to the first heating device or to the second heating device. Therein, the nominal power levels suppliable to the first heating device and the nominal power level suppliable to the second heating device may be identical or may differ from one another. Unless specified otherwise, however, the “nominal power level” refers to the nominal power level suppliable by the power source to any one of or both the first heating device and the second heating device.FTR4067

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[0121] Further, “during the occurrence of the user inhalation” is to be construed broadly herein, and may mean or include “during at least a part of the user inhalation”, respectively, “during at least a part of a duration of the user inhalation”.

[0122] As used herein, “before the occurrence of the user inhalation” may refer to a time instant or time period preceding or directly preceding the start, onset, initiation and / or occurrence of the user inhalation.

[0123] The control circuitry can be configured to deactivate the supply of electrical power to the second heating device before the occurrence of the user inhalation, and increase the supply of electrical power to a nominal power level during the occurrence of the user inhalation and / or upon detecting start thereof. Alternatively or additionally, the control circuitry can be configured to activate the supply of electrical power to the second heating device at the occurrence of the user inhalation, at the start of the user inhalation, and / or upon detecting the occurrence of the user inhalation. For instance, the second heating device may only be powered or supplied with electrical power during at least a part of a user inhalation, while the second heating device may be deactivated or switched off at times where no user inhalation occurs. Hence, energy consumption can be reduced. Alternatively, however, the second heating device may be powered at a first power level, for example the initial power level, at times where no user inhalation occurs, and may be powered at a second power level, for example the nominal power level, which can be higher than the first power level during at least a part of a duration of the user inhalation.

[0124] The control circuitry can be configured to maintain the first heating device at a reduced power level or deactivated between start of the user inhalation and detecting that the second heating device has reached the nominal power level. For example, the first heating device may remain deactivated and / or may be powered at reduced power level (with respect to before occurrence of the user inhalation) for a period of time of about 1 ms to about 1 second, for example about 5 ms to about 700 ms, preferably about 10 ms to about 700 ms, more preferably less than 200 ms, from the start of the user inhalation, respectively from the instant in time of detecting the start of the user inhalation.

[0125] The control circuitry may further be configured to activate and / or increase, during the occurrence of the user inhalation, the supply of electrical power to the first heating device upon determining that a nominal power level of the power supplied to the second heating device is reached. When the nominal power level is reached by the second heating device, the temperature of the second heating device has increased and may potentially continue to increase or at least maintain its temperature for a short period of time. Hence, when the nominal power level is reached at the second heating device, the second heating device can effectively heat the incoming air in the airflow path and hence the aerosol-forming article or substrate. On the other hand, as the electric power to the first heating device was reduced at the start of the userFTR4067

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[0127] inhalation, a temperature of the first heating may have slightly decreased. This temperature decrease of the first heating device may be compensated by the control circuitry by activating the first heating device or increasing the electrical power supplied thereto. Also, activating the first heating device or increasing the power supplied thereto can ensure that the aerosol-forming substrate is sufficiently heated during the subsequent time period of the user inhalation, for example to or above a volatilization temperature to generate aerosol inhalable by the user.

[0128] The volatilization temperature may also be referred to as vaporization temperature and may denote a temperature sufficient to vaporize one or more ingredients from the substrate.

[0129] In an example, the control circuitry can be configured to activate or increase the supply of electrical power to the first heating device, for example gradually or step-wise, within a period of time of about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms, for example from the instant in time the second heating device reached the nominal power level and / or upon detecting that the second heating device has reached the nominal power level.

[0130] In an example, the electrical power provided to the first heating device may be increased during the occurrence of the user inhalation, for example upon detecting that the second heating device has reached the nominal power level, to a power level, at which the first heating device was operated before the occurrence or start of the user inhalation. Accordingly, the power level of the electrical power supplied to the first heating device may be increased during at least a part of a duration of the user inhalation to the same power level as supplied to the first heating before start of the user inhalation. This may allow to compensate a cooling effect of the air drawn by the user during the user inhalation through the upstream airflow path and towards or through the heating chamber where the first heating device may be arranged.

[0131] In an example, the control circuitry can be configured to increase the supply of electrical power to the first heating device to the power level before the user inhalation or start thereof, for example gradually or step-wise, within a period of time of about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms, from the instant in time the second heating device reached the nominal power level. Optionally, the power supply to the first heating device may be increased as fast as possible and / or upon detecting that the second heating device has reached the nominal power level.

[0132] In a further example, the control circuitry can be configured to increase the power provided to the first heating device during the occurrence of the user inhalation to a power level exceeding a power level, at which the first heating device was operated before the occurrence or start of the user inhalation. Accordingly, the power level of the electrical power supplied to the first heating device may be increased during at least a part of a duration of the user inhalation to a power level exceeding the power level supplied to the first heating before start of the user inhalation. Also thisFTR4067

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[0134] approach may allow to compensate the cooling effect of the air drawn by the user during the user inhalation.

[0135] In an example, the control circuitry can be configured to increase the supply of electrical power to the first heating device to the power level exceeding the power level before the user inhalation, for example gradually or step-wise, within a period of time of about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms, from the instant in time the second heating device reached the nominal power level and / or upon detecting that the second heating device has reached the nominal power level. Optionally, the power supply to the first heating device may be increased as fast as possible upon detecting that the second heating device has reached the nominal power level.

[0136] The control circuitry may further be configured to maintain the first heating device at the power level before occurrence or start of the user inhalation or at a power level exceeding this power level for substantially the remaining time of the user inhalation. In an example, the first heating device may be maintained at the power level before occurrence or start of the user inhalation or at a power level exceeding this power level for a time period of about 10 ms to about 3.5 seconds, for example about 100 ms to about 2.5 seconds, preferably about 500 ms to about 2 seconds.

[0137] In yet a further example, the control circuitry may be configured to reduce the power provided to the first heating device towards an end of the user inhalation or upon termination of the user inhalation. For example, the control circuitry can be configured to reduce the power supplied to the first heating device upon determining that the user inhalation has ended, respectively, upon detecting termination of the user inhalation or shortly before termination of the user inhalation. Alternatively to reducing the power to the first heating device, the power supply may be stopped completely, respectively, the first heating device may be deactivated. Reducing the power supply to or deactivating the first heating device can allow to reduce energy consumption and avoid over-heating of the substrate.

[0138] As used herein, “towards the end of the user inhalation” may refer to an instant in time or a short time period directly preceding the instant in time of termination of the user inhalation. In an example, “towards the end of the user inhalation” may include about 1 ms to about 500 ms, for example about 5 ms to about 250 ms, preferably about 10 ms to about 100 ms.

[0139] In an example, the power supplied to the first heating device may be reduced to substantially the same power level, at which the first heating device was operated before the occurrence or start of the user inhalation. For instance, the control circuitry can be configured to reduce the power level to or deactivate the first heating device upon termination of and / or upon detecting termination of the user inhalation, for example gradually or step-wise, within a period of time of about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within aboutFTR4067

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[0141] 1 ms to about 100 ms, from the end of the user inhalation, respectively from the instant in time of detecting termination or end of the user inhalation. Optionally, the power to the first heating device may be reduced as fast as possible upon detecting termination or end of the user inhalation.

[0142] In yet a further example, the control circuitry may be configured to reduce, upon determining that the user inhalation has ended or upon detecting termination of the user inhalation, the power supplied to the first heating device to a power level below a power level, at which the first heating was operated before the occurrence or start of the user inhalation. For instance, the control circuitry can be configured to reduce the power level to the first heating device to said power level below the power level before occurrence or start of the user inhalation, for example gradually or step-wise, within a period of time of about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms, from the end of the user inhalation, respectively from the instant in time of detecting termination or end of the user inhalation. Optionally, the power to the first heating device may be reduced as fast as possible upon detecting termination or end of the user inhalation.

[0143] The control circuitry may further be configured to determine when the first heating device has reached said power level that is below the power level before occurrence or start of the user inhalation, and in response thereto, increase the power supply to the first heating device to the power level, at which the first heating device was operated before the occurrence or start of the user inhalation. A time period for the increase to the power level before the user inhalation may be gradual or step-wise, and may for example be performed within a period of time of about 5 ms to about 2 seconds, for example about 10 ms to about 1 second, preferably within about 100 ms to about 500 ms.

[0144] In a further example, the control circuitry can be configured to decrease the power provided to the second heating device towards an end of the user inhalation. For example, the control circuitry can be configured to reduce the power supplied to the second heating device upon determining that the second heating device has reached the nominal power level or upon determining that the second heating device has been operated at the nominal power level for a predetermined period of time. Such predetermined period of time may, for example, range from about 5 ms to about 2 seconds, for example about 10 ms to about 1 second, preferably about 100 ms to about 500 ms. Reducing the power supply to the second heating device can allow to reduce energy consumption and avoid over-heating of the substrate. For instance, the control circuitry can be configured to reduce the power level to or deactivate the second heating device towards the end of the user inhalation, for example gradually or step-wise, within a period of time of about 0.5 ms to about 1 second, for example about 0.5 ms to about 500 ms, in particular about 0.5 to about 200 ms for example about 1 ms to about 150 ms, preferably within about 1 ms toFTR4067

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[0146] about 100 ms, directly preceding the instant in time of termination of the user inhalation or detection thereof.

[0147] The control circuitry can, for example, be configured to reduce the power supplied to the second heating device from the nominal power level to a final power level at the end or at the instant in time of termination of the user inhalation. Therein, the final power level may be between an initial power level of the power supplied to the second heating device at the start of the user inhalation and the nominal power level supplied to the second heating device during the user inhalation. Alternatively, however, the final power level may correspond to the initial power level and / or may be zero Watts.

[0148] For instance, the control circuitry can be configured to reduce the power level to or deactivate the second heating device to the final power level, for example gradually or step-wise, within a period of time of about 5 ms to about 2 seconds, for example about 10 ms to about 1 second, preferably about 100 ms to about 500 ms, from the instant in time of reaching the nominal power level at the second heating device or after maintaining the second heating device for a predetermined period of time at the nominal power level.

[0149] In yet a further example, the control circuitry can be configured to deactivate the supply of electrical power to the second heating device upon detecting termination of the user inhalation. For instance, the second heating device may be deactivated upon detecting termination of the user inhalation, for example gradually or step-wise, within a period of time of about 0.5 ms to about 1 second, for example about 0.5 ms to about 500 ms, in particular about 0.5 to about 200 ms for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms, from the end of the user inhalation, respectively from the instant in time of detecting termination or end of the user inhalation. Optionally, the power to the second heating device may be reduced as fast as possible upon detecting termination of the user inhalation.

[0150] The aerosol-forming article can have a substantially rectangular parallelepiped, oblong and / or cuboid shape defining two opposing main faces and two opposing side faces or lateral faces, the aerosol-forming article including an aerosol-forming substrate arranged between the two opposing main faces, preferably wherein the aerosol-forming article comprises an air inlet and an air outlet or aerosol-outlet located opposite of each other on the smallest faces of the rectangular parallelepiped shaped aerosol-forming article. The air inlet of the aerosol-forming article may also be referred to herein as upstream air inlet of the article, and the air or aerosol outlet of the article may also be referred to herein as downstream air or aerosol outlet of the aerosol-forming article. Generally, however, the present is not limited to substantially rectangular parallelepiped-shaped aerosol-forming articles, but other geometries, such as for example cylindrical or stick-like shaped aerosol-forming articles, are possible.FTR4067

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[0152] The aerosol-forming device may have a longitudinal axis, a transverse axis, and a normal axis, each being transverse, in particular orthogonal, to each other. The longitudinal direction of the aerosol-forming device may be parallel to the longitudinal axis and / or may extend from a proximal end or portion towards a distal end or portion of the aerosol-forming device. Therein, the proximal end or portion may be associated with a downstream element of the device, also referred to as mouthpiece portion, or a mouthpiece that can be contacted by a user’s mouth during aerosol generation or consumption. The longitudinal axis may be coaxial to or define a center axis and / or an insertion axis of the aerosol-forming device for inserting the aerosol-forming article into the device. Unless otherwise stated, a reference to a longitudinal axis may mean the center axis or longitudinal center axis. A transverse direction of the aerosol-forming device may be parallel to the transverse axis, and a normal direction of the aerosol-forming device may be parallel to the normal axis. When the transverse axis and the longitudinal axis of the aerosol-forming device are both arranged, oriented or aligned in a horizontal plane, the normal axis of the aerosol-forming device defines a vertical axis of the aerosol-forming device. Therefore, the normal axis or direction may also be referred to herein as vertical axis or direction of the aerosol-forming device.

[0153] The longitudinal axis of the aerosol-forming device may define or be coaxial to a longitudinal axis of the heating chamber. The transverse axis of the aerosol-forming device may define or be coaxial to a transverse axis of the heating chamber. The normal axis of the aerosol-forming device may define or be coaxial to a normal axis of the heating chamber.

[0154] Accordingly, at least when the aerosol-forming article is at least partly inserted in the heating chamber, the longitudinal axis of the aerosol-forming device may define or be coaxial to a longitudinal axis of the aerosol-forming article. The transverse axis of the aerosol-forming device may define or be coaxial to a transverse axis of the aerosol-forming article. The normal axis of the aerosol-forming device may define or be coaxial to a normal axis of the aerosol-forming article.

[0155] Further, the longitudinal direction may define and / or may be parallel to an insertion direction, along which the aerosol-forming article may be inserted into the heating chamber. Accordingly, the longitudinal axis may define and / or may be parallel to the insertion axis.

[0156] An extension, length or size of the aerosol-forming device, the heating chamber and / or the aerosol-forming article may be longer in longitudinal direction than in directions transverse, for example orthogonal, thereto. Specifically, the aerosol-forming device, the heating chamber and / or the aerosol-forming article, respectively, may have a length measured along the longitudinal direction or axis, a width measured along the transverse direction or axis, and a thickness or height measured along the normal axis or direction of the aerosol-forming device, the heating chamber and / or the aerosol-forming article, respectively. The transverse axis may also be referred to herein as width axis, and the transverse direction may also be referred to herein as width direction. Further, the normal axis may also be referred to herein as height or thicknessFTR4067

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[0158] axis, and the normal direction may also be referred to herein as height or thickness direction of the aerosol-forming device, the heating chamber and / or the aerosol-forming article, respectively.

[0159] The aerosol-forming article may have a substantially rectangular parallelepiped shape. Alternatively or additionally, the aerosol-forming article may be plate-like or cuboid formed. The aerosol-forming article may comprise two opposing main surfaces, which may be substantially flat or planar. When the aerosol-forming article is inserted into the aerosol-forming device, a surface normal vector of the two opposing main surfaces may be parallel to the normal axis of the aerosol-forming device. Further, the aerosol-forming article may comprise two end faces or surfaces, in particular substantially flat or planar end faces, which are arranged opposite to each other and are spaced apart from each other in longitudinal direction of the aerosol-forming device, when the aerosol-forming article is inserted into the aerosol-forming device. The two end faces or surfaces may form the smallest surfaces of the aerosol-forming article, and are thus also referred to as smallest faces or surfaces of the aerosol-forming article. Moreover, the aerosol-forming article may comprise two lateral faces or side faces, in particular substantially flat or planar lateral faces or surfaces, which are arranged opposite to each other and are spaced apart from each other in transverse direction of the aerosol-forming device, when the aerosol-forming article is inserted into the aerosol-forming device. Accordingly, each of the lateral faces or side faces of the aerosol-forming article may have a surface normal vector substantially parallel to the transverse axis of the aerosol-forming device, when the aerosol-forming article is inserted into the aerosol-forming device.

[0160] The heating chamber may have a substantially rectangular parallelepiped shape and / or may be configured to receive a substantially rectangular parallelepiped shaped aerosol-forming article. The heating chamber may comprise two opposing main surfaces, which may be substantially flat or planar. Optionally, each of the two main surfaces may be defined or provided by a heating element of the first heating device of the aerosol-forming device, for example a substantially flat or planar heating element. A surface normal vector of the two opposing main surfaces may be parallel to the normal axis of the aerosol-forming device. Further, the heating chamber may comprise two end faces or surfaces, in particular substantially flat or planar end faces, which are arranged opposite to each other and are spaced apart from each other in longitudinal direction of the aerosol-forming device. The two end faces or surfaces may form the smallest surfaces of the heating chamber. It is noted that these surfaces or faces may refer to an open volume provided by the heating chamber. For example, at least one of the end faces or surfaces may be an open end, for example defining an insertion opening for the aerosol-forming article. Moreover, the heating chamber may comprise two lateral faces, in particular substantially flat or planar lateral faces or surfaces, which are arranged opposite to each other and are spaced apart from each other in transverse direction of the aerosol-forming device. Accordingly, each ofFTR4067

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[0162] the lateral faces of the heating chamber may have a surface normal vector substantially parallel to the transverse axis of the aerosol-forming device.

[0163] As mentioned above, the aerosol-forming article may have an air inlet, for example arranged at a distal end of the article, and air or aerosol outlet, for example arranged at a proximal end of the article. The air inlet and aerosol-outlet may be located opposite of each other on the smallest faces or surfaces of the substantially rectangular parallelepiped shaped aerosol-forming article. The air inlet and the air outlet and may be spaced apart from each other along the longitudinal direction.

[0164] The aerosol-forming article may have a length, for example as measured along the insertion axis and / or along the longitudinal direction or axis of the aerosol-forming device or article, in a range between 20 mm and 40 mm, preferably between 25 mm and 35 mm, more preferably about 30 mm. The aerosol-forming article may have a width, for example as measured along the transverse direction of the aerosol-forming device or article, in a range between 7 mm and 15 mm, preferably between 9 mm and 13 mm, more preferably about 11 mm. The aerosol-forming article may have a thickness or height, for example as measured along the normal direction of the aerosol-forming device or article, of between 1 mm and 10 mm, for example between 2 mm and 5 mm, preferably between 2.5 mm and 4 mm, more preferably about 3.1 mm. Therein, the length may refer to a minimum, mean or maximum length, the width may refer to a minimum, mean or maximum width and the thickness may refer to a minimum, mean or maximum thickness, respectively, height of the aerosol-forming article.

[0165] The aerosol-forming substrate may have a substantially planar, cuboid, or rectangular parallelepiped shape and may be located between a top and bottom cover sheet inside the aerosol-forming article, wherein the substrate may have a length, for example as measured along the insertion axis and / or along the longitudinal direction of the aerosol-forming device or article, of about 8 mm to 15 mm, preferably about 12 mm. The substrate may further have a width, for example as measured perpendicularly to the insertion direction and / or along the transverse direction of the aerosol-forming device or article, of about 6 mm to 13 mm, preferably about 8 mm. Therein, the length may refer to a minimum, mean or maximum length, and the width may refer to a minimum, mean or maximum width of the aerosol-forming substrate.

[0166] The substrate may particularly be or include a solid substrate material, although it is not limited thereto. Alternatively or additionally, the aerosol-forming substrate may be a solid substrate. For example, the substrate may include tobacco-based material, herbs, Cannabisbased material, or other solid substrate material. Optionally, however, also moisture, other liquid constituents and / or one or more active ingredients may be comprised in the substrate. It is noted, though, that the present disclosure is not limited to solid substrates or substrates containing solidFTR4067

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[0168] material, but can be applied to vaporizers or vaping devices that generate aerosol by vaporizing liquid substrate material.

[0169] A weight or mass of the aerosol-forming substrate weight may be in a range between about 100 mg and about 260 mg, more preferably between about 130 mg and about 240 mg, even more preferably about 150 mg and about 210 mg, most preferably about 180 mg.

[0170] The aerosol-forming substrate may comprise a plurality of granules or beads of substrate material, wherein a bulk density of the aerosol-forming substrate may be in a range of about 0.4 g / cm3to about 0.8 g / cm3, preferably about 0.6 g / cm3. Therein, the bulk density may be defined as the mass of the particles divided by the total volume they occupy. This volume can include the space between granules or beads as well as the space within the particles themselves.

[0171] The aerosol-forming substrate may comprise a plurality of granules or beads of substrate material, wherein a density of single granules or beads of the substrate may be at least 0.75 grams per cubic centimetre, more preferably at least 0.8 grams per cubic centimetre, more preferably at least 0.9 grams per cubic centimetre, more preferably at least 1 gram per cubic centimetre, more preferably at least 1.1 grams per cubic centimetre, more preferably at least 1.2 grams per cubic centimetre.

[0172] The aerosol-forming substrate may comprise a plurality of granules or beads of substrate material, wherein a density of single granules or beads of the substrate of the may be less than or equal to 2 grams per cubic centimetre, more preferably less than or equal to 1.95 grams per cubic centimetre, more preferably less than or equal to 1.9 grams per cubic centimetre, more preferably less than or equal to1.85 grams per cubic centimetre, more preferably less than or equal to 1.8 grams per cubic centimetre.

[0173] The aerosol-forming article can comprise a cavity, also referred to as substrate chamber, and a frame positioned between the two opposing main faces of the aerosol-forming article. The frame may at least partly define the cavity. The cavity may be configured and / or arranged to accommodate or receive the aerosol-forming substrate. In particular, the cavity may be at least partially, preferably entirely filled with aerosol-forming substrate.

[0174] The cavity may have a length, for example measured along the longitudinal axis of the aerosol-forming article or device, of at least 10 millimetres, or at least 12 millimetres. The cavity may have a length of less than or equal to 20 millimetres, or less than or equal to 15 millimetres. For example, the cavity may have a length of between 10 millimetres and 20 millimetres, or between 12 millimetres and 15 millimetres.

[0175] The cavity may have a width, for example measured along the transverse axis or width direction of the aerosol-forming device, of at least 5 millimetres, or at least 6 millimetres. The cavity may have a width of less than or equal to 10 millimetres, or less than or equal to 8FTR4067

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[0177] millimetres. For example, the cavity may have a width of between 5 millimetres and 10 millimetres, or between 6 millimetres and 8 millimetres.

[0178] The cavity may have a depth or thickness, for example measured along the normal direction of the aerosol-forming device, of at least 2 millimetres, or at least 3 millimetres. The cavity may have a depth of less than or equal to 5 millimetres, or less than or equal to 4 millimetres. For example, the cavity may have a depth of between 2 millimetres and 5 millimetres, or between 3 millimetres and 4 millimetres, for example between 2.5 millimetres and 4 mm millimetres.

[0179] The cavity may have a volume of at least 200 cubic millimetres, or at least 250 cubic millimetres. The cavity may have a volume of less than or equal to 400 cubic millimetres, or less than or equal to 350 cubic millimetres. For example, the cavity may have a volume of between 200 cubic millimetres and 400 cubic millimetres, or between 250 cubic millimetres and 350 cubic millimetres. The cavity may substantially be completely filled with substrate material, for example a plurality of beads or granules. Accordingly, the dimensions of the cavity may correspond to dimensions, volumes and sizes of the aerosol-forming substrate may substantially correspond to or define the dimensions, volumes and sizes of the aerosol-forming substrate.

[0180] The aerosol-forming substrate may have a length, for example measured along the longitudinal axis of the aerosol-forming article or device, of at least 10 millimetres, or at least 12 millimetres. The aerosol-forming substrate may have a length of less than or equal to 20 millimetres, or less than or equal to 15 millimetres. For example, the aerosol-forming substrate may have a length of between 10 millimetres and 20 millimetres, or between 12 millimetres and 15 millimetres.

[0181] The aerosol-forming substrate may have a width, for example measured along the transverse axis or width direction of the aerosol-forming device, of at least 5 millimetres, or at least 6 millimetres. The aerosol-forming substrate may have a width of less than or equal to 10 millimetres, or less than or equal to 8 millimetres. For example, the aerosol-forming substrate may have a width of between 5 millimetres and 10 millimetres, or between 6 millimetres and 8 millimetres.

[0182] The aerosol-forming substrate may have a depth or thickness, for example measured along the normal direction of the aerosol-forming device, of at least 2 millimetres, or at least 3 millimetres. The aerosol-forming substrate may have a depth or thickness of less than or equal to 5 millimetres, or less than or equal to 4 millimetres. For example, the aerosol-forming substrate may have a depth or thickness of between 2 millimetres and 5 millimetres, or between 3 millimetres and 4 millimetres, for example between 2.5 millimetres and 4 mm millimetres.

[0183] The aerosol-forming substrate may have a volume of at least 200 cubic millimetres, or at least 250 cubic millimetres. The aerosol-forming substrate may have a volume of less than or equal to 400 cubic millimetres, or less than or equal to 350 cubic millimetres. For example, theFTR4067

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[0185] aerosol-forming substrate may have a volume of between 200 cubic millimetres and 400 cubic millimetres, or between 250 cubic millimetres and 350 cubic millimetres.

[0186] The main faces or surfaces of the aerosol-forming article may comprise or be made of a cover sheet, which may comprise paper-based material, for example rolling paper, which may be fixed to the frame and, together with the frame, may define the substrate chamber or cavity, which may be filled with any type of aerosol-forming substrate, in particular solid substrate material, for example in bulk form or in the form of a plurality of granules or beads. Accordingly, each of the main faces or surfaces of the aerosol-forming article may comprise or constitute a cover-sheet, which may be heated by the first heating device and / or the heating elements thereof.

[0187] A distance or separation between the two opposing heating elements of the first heating device may be such that the aerosol-forming article fits therebetween, and / or such that the two opposing heating elements contact the two opposing main faces of the article. Accordingly, a distance or separation between the heating elements, for example measured along the normal direction of the aerosol-forming device or article, may substantially correspond to, be equal to, match or be slightly smaller than the thickness of the aerosol-forming article, such that heating surfaces of the heating elements of the first heating device may contact the two opposing main faces of the aerosol-forming article, for example when the aerosol-forming article is inserted into the heating chamber. Alternatively or additionally, a distance or separation between the two opposing heating elements of the first heating device, for example as measured along the normal direction of the aerosol-forming device or article, may be between 1 mm and 10 mm, for example between 2 mm and 5 mm, preferably between 2.5 mm and 4 mm, more preferably about 3.1 mm.

[0188] The heating chamber may be configured to at least partially receive the aerosol-forming article having a length, e.g. as measured along the insertion axis in longitudinal direction, and / or parallel to the longitudinal axis, in a range between 20 mm and 40 mm, preferably between 25 mm and 35 mm, more preferably about 30 mm, having a width, e.g. measured in transverse direction of the aerosol-forming device, in a range between 7 mm and 15 mm, preferably between 9 mm and 13 mm, more preferably about 11 mm, and a thickness or height, e.g. measured in normal direction of the aerosol-forming device, of between 1 mm and 10 mm, for example between 2 mm and 5 mm, preferably between 2.5 mm and 4 mm, more preferably about 3.1 mm. Therein, the length may refer to a minimum, mean or maximum length, the width may refer to a minimum, mean or maximum width and the thickness may refer to a minimum, mean or maximum thickness, respectively, height of the aerosol-forming article.

[0189] The heating chamber may be configured to have an insertion depth along the insertion axis in a range between 10 mm and 35 mm, preferably in a range between 15 mm and 30 mm, more preferably between 15 mm and 25 mm. The insertion depth may refer to a distance by which the aerosol-forming article can be inserted into the heating chamber. The insertion depth may forFTR4067

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[0191] example correspond to a distance, for example minimum, mean or maximum distance, between a proximal end face of the heating chamber and a distal end face of the heating chamber. The insertion depth may refer to a minimum, mean or maximum distance or insertion depth.

[0192] The insertion depth may define or substantially correspond to a length of the heating chamber, for example measured in longitudinal direction of the aerosol-forming device. Accordingly, a length of the heating chamber may be in a range between 10 mm and 35 mm, preferably in a range between 15 mm and 30 mm, more preferably between 15 mm and 25 mm. The length may refer to a minimum, mean or maximum length.

[0193] The heating chamber may be configured to have an insertion depth that is shorter than a length of the aerosol-forming article. Accordingly, the aerosol-forming article, when inserted into the heating chamber, may protrude from a proximal end of the heating chamber, for example by about 1 mm to 30 mm, for example 2 mm to 20 mm, preferably about 5 mm to 15 mm, more preferably about 5 mm to about 10 mm.

[0194] The heating chamber may have a width, for example measured along the transverse direction of the aerosol-forming device, between the two inner small side faces or lateral faces between 7.2 mm and 15.2 mm, preferably between 9.2 mm and 13.2 mm, more preferably about 11.2 mm. The width may be minimum, mean or maximum width.

[0195] The heating chamber may have a width, for example measured along the transverse direction of the aerosol-forming device, between the two inner small side faces or lateral faces to provide for an interference fit, a press-fit, or a friction-fit with the small side surfaces or lateral faces of aerosol-forming article. Hence, the aerosol-forming article may be laterally positioned or fixed in the heating chamber.

[0196] The heating chamber may have a height or thickness, for example measured along the normal direction of the aerosol-forming device, between two inner large side faces or main faces of a heater casing or heating elements between 2 mm and 10 mm, more preferably between 3 mm and 8 mm, even more preferably between 4 mm and 6 mm. The height may be minimum, mean or maximum height.

[0197] The aerosol-forming device may comprise one or more main air inlets, device inlets or air inlets configured to receive an airflow from the external environment of the aerosol-forming device, wherein the one or more main air inlets are in fluid communication with the upstream airflow path arranged upstream of the heating chamber. For instance, one or more airflow path structures of the device may fluidly couple the one or more main air inlets with the upstream airflow path.

[0198] The aerosol-forming device may further comprise a device body, also referred to as body or body part, defining a main axis of extension of the aerosol-forming device, which may be parallel to the longitudinal axis of the device and / or the insertion direction for inserting the aerosol-FTR4067

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[0200] forming article into the aerosol-forming device. The aerosol-forming device may further comprise a downstream element movably attached to the device body or body, such that the device body and the downstream element are movable relative to each other between an open position and a use position, wherein access to the heating chamber is provided in the open position, such that the aerosol-forming article is removable from or insertable into the heating chamber in the open position, and wherein the heating chamber is closed in the closed position. The downstream element may also be referred to herein as mouthpiece portion, and may generally refer to a part of the device or the housing thereof that is displaceable or movable relative to the device body.

[0201] The downstream element of the aerosol-forming device may be slidably and / or rotatably attached or coupled to the device body, such that the downstream element is movable, for example relative to the device body, from the open position to the use position. The downstream element and the device body may be moved or displaced relative to each other along the longitudinal direction, parallel to the longitudinal axis between the open position and the use position, or in another direction.

[0202] The use position and the open position of the aerosol-forming device may generally refer to two different configurations of the aerosol-forming device. Also, the terms open position and closed position may be used herein with reference to one or more elements or components of the aerosol-forming device, thereby describing different configurations of said components or elements.

[0203] For example, between the open position and the use position, the device body may be moved or displaced relative to the downstream element of the aerosol-forming device. The device body may be moved relative to the downstream element, for example parallel to the longitudinal axis or along the longitudinal direction of the aerosol-forming device. The aerosol-forming device being in the open position, respectively, being in the closed position, may be interchangeably or synonymously used herein with the device body and / or downstream element being in the open position, respectively, being in the closed position.

[0204] In the use position, the heating chamber may be closed and / or covered by the downstream element and the device body. Accordingly, the heating chamber may not be accessible, respectively, may be inaccessible for a user to insert the aerosol-forming article or remove it therefrom. Alternatively or additionally, the aerosol-forming article may only be inserted into the heating chamber when the device body and the downstream element are displaced or moved relative to each other out of the use position, for example are displaced towards the open position. Optionally, generation of aerosol may only be allowed in the use position.

[0205] In the open position, the heating chamber may be accessible, for example for inserting an aerosol-forming article into or removing it from the heating chamber.FTR4067

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[0207] A relative displacement or movement of the device body and the downstream element from the open position towards or into the use position may refer to a displacement or movement of the downstream element from a proximal end towards a distal end of the aerosol-forming device, and / or may refer to a displacement or movement of the device body from a distal end towards a proximal end of the aerosol-forming device. Accordingly, the device body and the downstream element may be moved or displaced towards each other, for example along or parallel to the longitudinal axis of the aerosol-forming device, when moving the device body and the downstream element from the open position towards or into the use position. Alternatively or additionally, the device body and the downstream element may be moved or displaced away from each other, for example along or parallel to the longitudinal axis of the aerosol-forming device, when moving the device body and the downstream element from the use position towards or into the open position. Alternatively or additionally, the device body and the downstream element may be moved away from each other based on rotating at least one of the device body and the downstream element.

[0208] As used herein, the terms “distal” and “proximal” describe the locations of components or elements in relation to a user holding or using the aerosol-forming device, for example using the aerosol-forming device to consume or inhale aerosol. Therein, “distal” can refer to a location or element that is farther away from the user, and “proximal” can refer to a location or element that is closer to the user.

[0209] The aerosol-forming device may further comprise an interconnection mechanism arranged between the downstream element and the device body, and permitting the movement between the open and the use position, wherein the movement includes a rotational movement, a linear movement, or combination of a rotational and linear movement. In particular, any mechanism described herein for moving or displacing the device body and the downstream element relative to each other between the open position and use position can be used.

[0210] The aerosol-forming device may further comprise a heating module arranged at least partly in the device body, wherein the heating chamber is arranged in the heating module, optionally, wherein the heating module is removable from the device body of the aerosol-forming device.

[0211] The heating module may be slidably arranged inside the device body to slide along the main axis of extension or longitudinal axis, wherein a spring biasing mechanism may optionally be configured to push the heating module to be at least partially outside the device body when the downstream element is in the open position. In other words, in the open position, the heating module may protrude from an end of the device body. For instance, this may allow to remove or replace the heating module.

[0212] The aerosol-forming device may further comprise an upstream fluidic interconnection element configured to provide a fluidic connection between the upstream airflow path upstream and the aerosol-forming article, wherein the upstream fluidic interconnection element comprisesFTR4067

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[0214] a blade structure surrounding the upstream airflow path along a central axis of the upstream airflow path, the blade structure having a first end configured to face an upstream air inlet of the aerosol-forming article, and a second end arranged opposite of the first end, wherein an outer wall of the blade structure has a sloped or tapered shape thereby increasing a thickness of the blade structure in a direction from the first end to the second end. In particular, the upstream fluidic interconnection element or its blade structure can be configured to cut or press into a wall or frame around an upstream air inlet of the aerosol-forming article, to provide for a fluidic connection and / or fluidic coupling between the upstream airflow path and the substrate of the aerosol-forming article.

[0215] By means of the blade structure of the upstream fluidic interconnection element cutting or pressing into the wall or frame surrounding the upstream air inlet, a substantially or at least partially sealed or fluid-tight coupling between the upstream airflow path and the substrate of the aerosol-forming article can be ensured or provided.

[0216] A cross-sectional area of an opening provided around an outer edge of the blade structure may be larger than a cross-sectional area of the upstream air inlet of the aerosol-forming article. This may ensure that the cross-sectional area of the upstream air inlet of the aerosol-forming article is not decreased by the blade structure at least partially pressing or cutting into the wall around or surrounding the upstream air inlet. Accordingly, the upstream air inlet may be kept open to let air pass therethrough.

[0217] A cross-sectional area of an opening provided around an outer edge of the blade structure may have one or more of a circular shape, an oval shape, a rectangular shape, and an irregular shape.

[0218] For example, a cross-sectional area of a flow path provided by the blade structure may have a rectangular shape with rounded corners. By means of the rectangular shape with rounded corners obstructions for air flowing therethrough may advantageously be avoided.

[0219] The aerosol-forming device may further comprise a downstream airflow path configured to provide an aerosol from the aerosol-forming article to an aerosol outlet of the device, and a downstream fluidic interconnection element configured to fluidically interconnect the downstream airflow path with the aerosol-forming article, wherein the downstream fluidic interconnection element includes a blade structure configured to cut or press into a wall around a downstream air outlet of the aerosol-forming article, to provide for a sealed fluidic connection between the aerosolforming article and the downstream airflow path.

[0220] By means of the blade structure of the downstream fluidic interconnection element cutting or pressing into the wall or frame surrounding the downstream air outlet, a substantially or at least partially sealed or fluid-tight coupling between the substrate of the aerosol-forming article and the downstream airflow path can be ensured or provided.FTR4067

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[0222] The downstream fluidic interconnection element, with or including the blade structure, may be in fluidic interconnection with the downstream airflow path and optionally with a mouthpiece of the aerosol-forming device, which mouthpiece may be movable relative to the heating chamber by either a rotational movement, a linear movement, or a combination of a rotational and linear movement. Accordingly, air flowing or passing through the downstream fluidic interconnection element with the associated blade structure may flow into downstream airflow path and optionally into the mouthpiece. In other words, the downstream fluidic interconnection element may guide the air or air flow from the aerosol-generating article and the downstream air outlet into the downstream airflow path and optionally into the mouthpiece, for example towards a user’s mouth.

[0223] The blade structure of the downstream fluidic interconnection element may be tapered or conical towards a center axis of the downstream airflow path, such that one or more tapered or conical walls of the blade structure are configured to press against an inner wall an inner wall of the aerosol-forming article, preferably wherein the blade structure of the downstream fluidic interconnection element forms a cutting end edge, such that the cutting end edge of the blade structure is configured to cut into the wall around a downstream aerosol outlet of the aerosolforming article. The downstream air outlet may also be referred to herein as aerosol outlet or downstream aerosol outlet of the aerosol-forming article.

[0224] The downstream and upstream fluidic interconnection elements may be formed and shaped corresponding to each other or identically, and may be arranged opposite to each other at the air inlet and aerosol outlet of the aerosol-forming article.

[0225] In an exemplary configuration, the second heating device may be arranged at least partly within, at, in thermal contact with or close to the upstream airflow path upstream. For instance, at least a part of the second heating device may protrude into the upstream airflow path, for example protrude from a wall of the upstream airflow path. Optionally, at least a part of a surface of the second heating device may be in direct contact with air in the upstream airflow path. Generally, this can allow to efficiently heat the air in the upstream airflow path, which can then heat the aerosol-forming article based on convective heating.

[0226] In an example, at least a part or portion of the upstream airflow path upstream of the heating chamber may be slit-like shaped. Hence, at least a part or portion of the upstream airflow path may be comparatively narrow, such that the airflow therethrough can be quickly and efficiently heated.

[0227] Alternatively or additionally, the second heating device may comprise a slit-shaped air channel and a resistive heating element, for example a substantially or preferably planar resistive heating element, arranged inside the slit-shaped air channel, such that two narrow airflow channels are formed above and below the resistive heating element, respectively, on two opposite sides of the resistive heating element. The slit-shaped or slot shaped air channel may also beFTR4067

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[0229] referred to herein as convective heating chamber. For instance, the air channels or gaps may be formed on two opposite sides, for example, on two planar sides or surfaces, of the resistive heating element.

[0230] By means of the second heating device with the resistive heating element, an efficient preheating or flash heating of the airflow may be ensured, for example such that air with elevated temperature can be directed into or towards the aerosol-forming article for generating aerosol.

[0231] The two narrow air flow channels (or air flow channels or gaps) may have a width in a range between 3 mm to 15 mm, and have a height of less than 0.5 mm and more than 0.05 mm, preferably less than 0.3 mm and more than 0.1 mm, preferably less than 0.25 mm to 0.1 mm. The width may, for example, be measured along the transverse or width direction of the aerosolforming device, and the height may be measured along the normal or height direction of the aerosol-forming device, or vice versa. Such dimensions, heights and / or widths may allow for an efficient and fast heating of the air flowing through the air flow channels.

[0232] In an example, two opposing walls forming the slit-shaped air channel of the second heating device and having the resistive heating element therebetween may not be heated. The walls may be made from an insulating material, avoiding heat transfer from the convective heating chamber into other parts of the device through other paths than the heated air flow. This may provide for efficient heating.

[0233] Generally, the configuration or design of the second heating device can ensure that the second heating device and / or its resistive heating element has a low thermal mass or generally low mass, which can allow to change its temperature based on a small airflow, while the walls of the convective heating chamber, respectively, the walls defining the slit-shaped air channel of the second heating device can have low thermal conductivity, to avoid taking on heat and thereby providing for a high thermal capacity to the upstream airflow path. Preferably, the walls should have a low thermal conductivity and a high specific heat capacity. Further, the walls should withstand the heat and comprise tox-appropriate material. For example, a ceramic material, zirconia, alumina or a combination thereof can be used for the walls defining the convective heating chamber and / or defining the walls of the slit-shaped air channel of the second heating device.

[0234] The two opposing walls forming the slit-shaped air channel of the second heating device and having the resistive element therebetween may have a structured, for example roughened or ragged, surface for causing an air flow turbulence. Additionally or alternatively, the surface of the resistive heating element may be structured, for example roughened or ragged, to cause turbulences. Also such air flow turbulence may be beneficial in terms of an efficient heating, for example as it may allow for a more homogenous temperature distribution.FTR4067

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[0236] An air flow direction in the second heating device may be in axis with an air flow direction in the heating chamber. For example, the air flow direction may be substantially parallel or along the longitudinal axis of the aerosol-forming device and / or article. By being in axis, obstructions in the flow path can be avoided, thereby also potentially preventing overheating.

[0237] The resistive heating element of the second heating device may be formed as a meandering or serpentine structure, wherein the meandering or serpentine structure may extend in-plane of the resistive heating element. For example, the resistive heating element may extend in a plane, and the meandering or serpentine structure may be directed along an extension direction thereof in said plane, wherein portions of the meandering or serpentine structure may alternately traverse the actual extension direction of the meandering or serpentine structure. The extension direction of the meandering or serpentine structure may, for example, extend in a direction transverse to the longitudinal direction of the aerosol-forming device, for example along the transverse or normal direction thereof.

[0238] For example, the resistive heating element of the second heating device may comprise a strip of a metal sheet, for example stainless steel, which may be perforated and / or include one or more perforation openings or holes. In other words, the resistive heating element may comprise a meshed metal strip. The strip may be bent into a stack of serpentine branches spanning between the two terminals of the resistive heating element. The branches may all be formed similarly, for example by having the same dimensions and / or extensions. The direction in which the stack of serpentine branches extends may be referred to as the stack direction, and the stack direction may be perpendicular or parallel to the longitudinal axis or direction of the aerosolforming device. The resistive heating element may be configured and / or arranged so that the air flowing through the convective heating chamber passes through the perforations forming the mesh of the strip, particularly along the stack direction. By flowing along the stack direction, the air may pass through perforations of every single branch in the stack, which ensures efficient and quick heat transfer to the air in the upstream airflow path. Also this configuration or design can ensure that the second heating device and / or its resistive heating element has a low thermal mass or generally low mass, which can allow to change its temperature based on a small airflow in a short period of time. Hence, temperature changes, and thus user inhalations, can be detected quickly and reliably.

[0239] The heating chamber of the aerosol-forming device may be configured to removably receive the aerosol-forming article, the aerosol-forming article having a substantially rectangular parallelepiped shape defining two opposing main faces and an aerosol-forming substrate arranged between the opposing main faces. Therein, the first heating device can comprise two opposing heating elements, for example resistive heating elements, forming a substantially rectangular parallelepiped heating volume therebetween for removably and at least partiallyFTR4067

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[0241] receiving the aerosol-forming article, the heating volume arranged at least partially inside the heating chamber. Further, at least one of the two heating elements can be made of an electrically conductive material. Accordingly, at least one of the heating elements may be configured to heat the substrate or article.

[0242] It is noted that the terms “substantially flat or planar” are to be construed broadly herein. Specifically, the terms flat or planar with reference to the heating elements, heating volume or heating chamber may merely mean or include a configuration, design and / or arrangement of one or more of these components to receive a rectangular parallelepiped shaped aerosol-forming article having a rectangular parallelepiped shape. For example, this can mean that the heating elements, heating chamber and / or heating volume is curved or convex towards the aerosolforming article. Also, the two opposing main faces of the aerosol-article may be referred to herein as substantially flat or planar, which can include slightly curved or structured surfaces of the aerosol-forming article.

[0243] In an example, both heating elements of the first heating device can be made from electrically conductive material and both heating elements can be configured to heat the substrate or article from the two opposing main faces or surfaces of the aerosol-forming article. Optionally, the first heating device may comprise one or two further heating elements which may be arranged opposite to each other in transverse direction and may be configured to heat the one or more lateral surfaces or faces of the aerosol-forming substrate.

[0244] The first heating device and / or the heating elements thereof may be arranged inside the heating chamber, wherein upon insertion of the aerosol-forming article into the heating chamber, at least a part of the first heating device and / or at least one of the heating elements thereof can be configured to move towards an adjacent side face of the heating chamber so that at least one heating element is pressed against one of the main faces of the aerosol-forming article. For example, at least a part of at least one of the heating elements may be moved by the insertion of the aerosol-forming article into the heating chamber.

[0245] Preferably, both heating elements can be moved towards the aerosol-forming article, such that both heating elements are pressed against a respective one of the main faces of the aerosolforming article. This can ensure good thermal contact between the one or both heating elements and the aerosol-forming article, thereby ensuring efficient heat transfer and heating of the substrate.

[0246] At least one of the heating elements, preferably both heating elements, of the first heating device can include a heating plate formed as a meandering track in the shape of a leaf spring. Optionally, the at least one heating element, preferably both heating elements, of the first heating device can include a heating plate with a plurality of parallelly-arranged heating tracks arranged in parallel to an insertion direction and / or longitudinal axis of the aerosol-forming device.FTR4067

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[0248] The aerosol-forming device may further include a heater casing made of a non-conductive material forming an outer shell around the two opposing heating elements of the first heating device. The heater casing may be part of a heater module or heating module of the aerosolforming device. Therein, two smaller inner side faces or lateral faces of the heater casing may form or define the inner small side faces or lateral faces of the heating chamber. Generally, the heater casing may insulate the housing or device body of the aerosol-forming device, such that heat dissipation can be reduced, for example such that the housing may not heat-up that much during a usage session and / or such that the heat is confined to the interior of the aerosol-forming device

[0249] For example, the two heating elements of the first heating device may oppose each other in normal direction and the small or smaller inner side faces of the heater casing may refer to lateral faces of the inner casing that define or constitute two lateral faces of the heating chamber, wherein the two lateral faces of the heater casing and / or the heating chamber may oppose each other in transverse direction of the aerosol-forming device.

[0250] According to a further aspect of the present disclosure, there is provided an aerosol-forming system comprising an aerosol-forming device, as described hereinabove and hereinbelow. The aerosol-forming system comprises one or both an aerosol-forming article for generating aerosol, and a companion device for charging and / or storing the aerosol-forming device.

[0251] As mentioned above, any disclosure herein related to the aerosol-forming device equally applies to the aerosol-forming system, and vice versa.

[0252] The companion device may also be referred to as charger case. The aerosol-forming device may be mechanically couplable to the companion device in order to store the aerosol-forming device and / or in order to charge an energy storage or power source of the aerosol-forming device via the companion device.

[0253] A mechanical coupling of the aerosol-forming device and the companion device may, in the context of the present disclosure, include a contact between a part or surface of the companion device and a part or surface of the aerosol-forming device. For instance, when coupling the aerosol-forming device with the companion device, a part of a housing or outer surface of the aerosol-forming device may be in contact or direct contact with a part of a housing, compartment or surface of the companion device. Accordingly, a mechanical coupling of the aerosol-forming device and the companion device can include a mechanical or physical contact between the aerosol-forming device and the companion device.

[0254] For example, the aerosol-forming device may be mechanically couplable to the companion device based on at least partly inserting the aerosol-forming device into the companion device, for example into a cavity, compartment or recess of the companion device. Alternatively orFTR4067

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[0256] additionally, the companion device may be mechanically couplable with the aerosol-forming device based on at least partly receiving the aerosol-forming device in the companion device.

[0257] In an exemplary configuration, the companion device may comprise a compartment, cavity or recess for at least partly receiving the aerosol-forming device, for example, such that the aerosol-forming device is at least partly encompassed in or surrounded by the companion device.

[0258] Alternatively or additionally, the aerosol-forming device may be mechanically couplable to the companion device based on attaching a housing of the aerosol-forming device to the companion device. To attach the housing to the companion device, the companion device may, for example, comprise engagement means configured to engage with the housing of the aerosolforming device or corresponding engagement elements formed at or by the housing of the aerosol-forming device.

[0259] The control circuitry of the aerosol-forming device or a dedicated charging circuitry of the aerosol-forming device may be configured to charge the energy storage or power source of the aerosol-forming device upon, based on or in response to mechanically coupling the aerosolforming device with the companion device.

[0260] According to a further aspect of the present disclosure, there is provided a method of controlling or operating an aerosol-forming device or system. The aerosol-forming device or system comprises a heating chamber configured to receive at least a part of an aerosol-forming article, an upstream airflow path arranged upstream of the heating chamber and in fluid communication with an external environment of the aerosol-forming device, such that air is drawable by a user in a user inhalation through the airflow path, a first heating device arranged at the heating chamber configured to heat an aerosol-forming substrate of an inserted aerosolforming article, a second heating device arranged in thermal contact with the upstream airflow path, a power source for supplying the first heating device and the second heating device with electrical energy, and control circuitry configured to control the first heating device, the second heating device and optionally the power source. The method comprises controlling, by means of the control circuitry, a supply of electrical power from the power source to the first heating device and the second heating device, such that at an occurrence of a user inhalation, the power provided to the first heating device is reduced while the power provided to the second heating device is increased.

[0261] The aerosol-forming device or system may comprise the elements, functions and characteristics, as described hereinabove and hereinbelow. Accordingly, any disclosure herein related to the aerosol-forming device or system equally applies to the method, and vice versa.

[0262] In an example, controlling the supply of electrical power can include:

[0263] detecting the occurrence of the user inhalation and / or a start of the user inhalation;FTR4067

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[0265] reducing or decreasing the power provided to the first heating device in response to detecting the occurrence of the user inhalation; and

[0266] increasing the power provided to the second heating device in response to detecting the occurrence of the user inhalation.

[0267] Optionally, the power provided to the first heating device may be reduced simultaneously or concurrently with increasing the power provided to the second heating device.

[0268] In an example, the power provided to the first heating device may be reduced at the occurrence or start of the user inhalation to a power level below a power level supplied to the first heating device before the occurrence of the user inhalation. Alternatively, the supply of electrical power to the first heating device may be stopped or deactivated at the occurrence or start of the user inhalation.

[0269] In a further exemplary implementation, the power supply to the second heating device may be increased at the occurrence or start of the user inhalation from an initial power level to a nominal power level during the occurrence or at least a part of a duration of the user inhalation.

[0270] Optionally, the supply of electrical power to the second heating device may be stopped or the second heating device may be deactivated before the occurrence or start of the user inhalation, and increased to the nominal power level during the occurrence or at least a part of a duration of the user inhalation.

[0271] In an example, the method may further comprise activating the supply of electrical power to the second heating device at the occurrence of the user inhalation, at the start of the user inhalation, and / or upon detecting the occurrence of the user inhalation, for example by the control circuitry.

[0272] The method may further comprise activating, during the occurrence or at least a part of a duration of the user inhalation, the supply of electrical power to the first heating device and / or activating the first heating device upon reaching a nominal power level of the power supplied to the second heating device, and / or upon determining that the nominal power level has been reached by the second heating device.

[0273] Alternatively or additionally, the method may further comprise increasing, during the occurrence or during at least a part of a duration of the user inhalation, the power provided to the first heating device upon reaching a nominal power level of the power supplied to the second heating device, and / or upon determining that the nominal power level has been reached by the second heating device.

[0274] In an example, the power provided to the first heating device may be increased during the occurrence or during at least a part of the duration of the user inhalation to a power level, at which the first heating device was operated before the occurrence of the user inhalation. Alternatively the power provided to the first heating device may be increased during the occurrence or duringFTR4067

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[0276] at least a part of the duration of the user inhalation to a power level exceeding the power level, at which the first heating device was operated before the occurrence of the user inhalation. Accordingly, the first heating device may either resume the power level before the user inhalation or may be powered at an even higher power level than before start of the user inhalation.

[0277] The method may further comprise reducing the power provided to the first heating device towards an end of the user inhalation, upon termination of the user inhalation and / or upon detecting termination of the user inhalation. For example, the power supply to the first heating device may be reduced to substantially the same power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0278] In a further exemplary implementation, the method may comprise reducing the power supplied to the first heating device after termination of the user inhalation, for example in response to determining termination of the user inhalation. For instance, the power supply to the first heating device may be reduced after termination of the user inhalation to a power level below a power level, at which the first heating was operated before the occurrence of the user inhalation. Further optionally, the method may comprise increasing the power supplied to the first heating device to the power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0279] In a further exemplary implementation, the method may comprise decreasing the power provided to the second heating device towards an end of the user inhalation. For instance, the power supply to the second heating device may be reduced from the nominal power level to a final power level at the end or time of termination of the user inhalation. Optionally, the final power level be between an initial power level of the power supplied to the second heating device at the start of the user inhalation and the nominal power level supplied to the second heating device during at least a part of the user inhalation.

[0280] Further optionally, the method may comprise deactivating the supply of electrical power to the second heating device upon termination of the user inhalation or upon detecting termination of the user inhalation.

[0281] The invention is defined in the claims. However, below there is provided a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0282] Example 1: An aerosol-forming device, comprising:

[0283] a heating chamber configured to receive at least a part of an aerosol-forming article; an upstream airflow path arranged upstream of the heating chamber and in fluid communication with an external environment of the aerosol-forming device, such that air is drawable by a user in a user inhalation through the airflow path towards the heating chamber;

[0284] a first heating device arranged at the heating chamber;FTR4067

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[0286] a second heating device arranged in thermal contact with the upstream airflow path; a power source for supplying the first heating device and the second heating device with electrical energy, and

[0287] control circuitry configured to control the first heating device and the second heating device based on controlling a supply of electrical power from the power source to the first heating device and the second heating device, such that at an occurrence of a user inhalation, the power provided to the first heating device is reduced while the power provided to the second heating device is increased.

[0288] Example 2: The aerosol-forming device according to the preceding example, wherein the control circuitry is further configured to:

[0289] detect the occurrence of the user inhalation and / or the start of the user inhalation; reduce the power provided to the first heating device in response to detecting the occurrence of the user inhalation; and

[0290] increase the power provided to the second heating device in response to detecting the occurrence of the user inhalation.

[0291] Example 3: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to simultaneously reduce the power provided to the first heating device and increase the power provided to the second heating device.

[0292] Example 4: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to reduce the power provided to the first heating device at the occurrence of the user inhalation to a power level below a power level of the power supplied to the first heating device before the occurrence of the puff.

[0293] Example 5: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to deactivate the supply of electrical power to the first heating device at the occurrence of the user inhalation.

[0294] Example 6: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to increase the power provided to the second heating device at the occurrence of the user inhalation from an initial power level to a nominal power level during the occurrence of the user inhalation.

[0295] Example 7: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to deactivate the supply of electrical power to the second heating device before the occurrence of the user inhalation, and increase the supply of electrical power to a nominal power level during the occurrence of the user inhalation.

[0296] Example 8: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to activate the supply of electrical power toFTR4067

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[0298] the second heating device at the occurrence of the user inhalation, at the start of the user inhalation, or upon detecting the occurrence of the user inhalation.

[0299] Example 9: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to activate and / or increase, during the occurrence of the user inhalation, the supply of electrical power to the first heating device upon determining that a nominal power level of the power supplied to the second heating device is reached.

[0300] Example 10: The aerosol-forming device according to the preceding examples, wherein the power provided to the first heating device is increased during the occurrence of the user inhalation to a power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0301] Example 11: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to increase the power provided to the first heating device during the occurrence of the user inhalation to a power level exceeding a power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0302] Example 12: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to reduce the power provided to the first heating device towards an end of the user inhalation or upon termination of the user inhalation.

[0303] Example 13: The aerosol-forming device according to the preceding example, wherein the power supplied to the first heating device is reduced to substantially the same power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0304] Example 14: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to reduce the power supplied to the first heating device upon determining that the user inhalation has ended.

[0305] Example 15: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to reduce, upon determining that the user inhalation has ended, the power supplied to the first heating device to a power level below a power level, at which the first heating was operated before the occurrence of the user inhalation.

[0306] Example 16: The aerosol-forming device according to the preceding example, wherein the control circuitry is configured to increase the power supplied to the first heating device to the power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0307] Example 17: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to decrease the power provided to the second heating device towards an end of the user inhalation.FTR4067

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[0309] Example 18: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to reduce the power supplied to the second heating device from the nominal power level to a final power level at the end of the user inhalation.

[0310] Example 19: The aerosol-forming device according to the preceding example, wherein the final power level is between an initial power level of the power supplied to the second heating device at the start of the user inhalation and the nominal power level supplied to the second heating device during the user inhalation.

[0311] Example 20: The aerosol-forming device according to any one of the preceding examples, wherein the control circuitry is configured to deactivate the supply of electrical power to the second heating device upon detecting termination of the user inhalation.

[0312] Example 21: The aerosol-forming device according to any one of the preceding examples, wherein the first heating device is configured to perform a continuous or intermittent heating operation during a usage session; and / or

[0313] wherein the second heating device is configured for a puff-on-demand heating operation. Example 22: The aerosol-forming device according to any one of the preceding examples, wherein the control is further configured to one or more of detect initiation or a start of the user inhalation, and detect termination or an end of the user inhalation.

[0314] Example 23: The aerosol-forming device according to the preceding example, wherein the control circuitry is configured to detect one or both initiation and termination of the user inhalation based on determining one or more of a change in a temperature and a change in an electrical resistance of at least one of a part of the first heating device and a part of the second heating device.

[0315] Example 24: The aerosol-forming device according to the preceding example, wherein the control circuitry is configured to detect one or both initiation and termination of the user inhalation based on a puff sensor of the aerosol-forming device.

[0316] Example 25: The aerosol-forming device according to any one of the preceding examples, wherein the first heating device comprises two opposing and optionally substantially flat heating elements defining the heating chamber or a heating volume therebetween that is configured to receive at least a part of the aerosol-forming article.

[0317] Example 25A: The aerosol-forming device according to the preceding example, wherein a distance or separation between the two opposing heating elements of the first heating device may be such that the aerosol-forming article fits therebetween and / or such that the two opposing heating elements contact the two opposing main faces of the article.

[0318] Example 25B: The aerosol-forming device according to the any one of examples 25 or 25A, wherein a distance or separation between the two opposing heating elements of the first heatingFTR4067

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[0320] device, is between 1 mm and 10 mm, for example between 2 mm and 5 mm, preferably between 2.5 mm and 4 mm, more preferably about 3.1 mm.

[0321] Example 26: The aerosol-forming device according to any one of the preceding examples, wherein the aerosol-forming article has a substantially rectangular parallelepiped shape defining two opposing main faces and two opposing side faces, the aerosol-forming article including an aerosol-forming substrate arranged between the two opposing main faces.

[0322] Example 27: The aerosol-forming device according to any one of the preceding examples, wherein the heating volume and / or the heating chamber defined by the two opposing heating elements has a substantially rectangular parallelepiped shape and / or is configured to removably receive at least a part of a substantially rectangular parallelepiped shaped aerosolforming article.

[0323] Example 28: The aerosol-forming device according to any one of the preceding examples, wherein the first heating device includes a conductive heating device configured to heat a substrate of the aerosol-forming article by conductive heating.

[0324] Example 29: The aerosol-forming device according to any one of the preceding examples, wherein the two opposing heating elements are resistive heating elements.

[0325] Example 31: The aerosol-forming device according to any one of the preceding examples, wherein the aerosol-forming device comprises a main air inlet configured to receive an airflow from the external environment of the aerosol-forming device, wherein the main air inlet is in fluid communication with the upstream airflow path.

[0326] Example 32: The aerosol-forming device according to any one of the preceding examples, further comprising:

[0327] a device body defining a main axis of extension of the aerosol-forming device and / or defining an insertion direction for inserting the aerosol-forming article into the aerosol-forming device; and

[0328] a downstream element movably attached to the device body, such that the device body and the downstream element are movable relative to each other between an open position and a use position, wherein access to the heating chamber is provided in the open position, such that the aerosol-forming article is removable from or insertable into the heating chamber, and wherein the heating chamber is closed in the closed position.

[0329] Example 33: The aerosol-forming device of the previous example, further comprising: an interconnection mechanism arranged between the downstream element and the device body, and permitting the movement between the open and the use position, wherein the movement includes a rotational movement, a linear movement, or combination of a rotational and linear movement.FTR4067

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[0331] Example 34: The aerosol-forming device according to any one of the preceding examples, wherein the second heating device includes a resistive heating device configured to convectively heat air in the upstream airflow path to heat at least heat a part of a substrate of the aerosol-forming article.

[0332] Example 35: The aerosol-forming device according to any one of the preceding examples, wherein the second heating device is arranged in the upstream airflow path, preferably wherein the upstream airflow path upstream is slit-like shaped.

[0333] Example 36: The aerosol-forming device according to the preceding example, wherein the second heating device comprises a slit-shaped air channel and a resistive heating element, for example a substantially or preferably planar resistive heating element, arranged inside the slitshaped air channel, such that two narrow air flow channels are formed above and below the resistive heating element.

[0334] Example 37: The aerosol-forming device according to the preceding example, wherein the resistive heating element of the second heating device is formed as a meandering or serpentine structure, extending in-plane of the resistive heating element.

[0335] Example 38: The aerosol-forming device according to any one of the preceding examples, wherein the resistive heating element is formed from a single sheet of metal; and / or wherein the resistive heating element comprises at least one strip of a metal sheet, optionally wherein the strip of metal sheet is perforated and / or includes one or more perforation openings or holes.

[0336] Example 39: The aerosol-forming device according to any one of the preceding examples, wherein the resistive heating element comprises at least one strip of a metal sheet, the at least one strip being bent or formed into a stack of a plurality of serpentine-like formed branches, preferably the branches of the stack spanning between two terminals of the resistive heating element; and optionally wherein the stack extends along a stack direction perpendicular or parallel to a longitudinal axis of the aerosol-forming device.

[0337] Example 40: An aerosol-forming system comprising an aerosol-forming device according to any one of the preceding examples and one or more of:

[0338] an aerosol-forming article for generating aerosol; and

[0339] a companion device for one or more of storing the aerosol-forming device and charging the aerosol-forming device.

[0340] Example 41: A method of controlling an aerosol-forming device comprising a heating chamber configured to receive at least a part of an aerosol-forming article, an upstream airflow path arranged upstream of the heating chamber and in fluid communication with an external environment of the aerosol-forming device, such that air is drawable by a user in a user inhalation through the airflow path, a first heating device arranged at the heating chamber configured to heatFTR4067

[0341] 48 / 80

[0342] an aerosol-forming substrate of an inserted aerosol-forming article, a second heating device arranged in thermal contact with the upstream airflow path, a power source for supplying the first heating device and the second heating device with electrical energy, and control circuitry configured to control the first heating device and the second heating device, the method comprising:

[0343] controlling, by means of the control circuitry, a supply of electrical power from the power source to the first heating device and the second heating device, such that at an occurrence of a user inhalation, the power provided to the first heating device is reduced while the power provided to the second heating device is increased.

[0344] Example 42: The method according to the preceding example, wherein controlling the supply of electrical power includes:

[0345] detecting the occurrence of the user inhalation and / or a start of the user inhalation; reducing the power provided to the first heating device in response to detecting the occurrence of the user inhalation; and

[0346] increasing the power provided to the second heating device in response to detecting the occurrence of the user inhalation.

[0347] Example 43: The method according to example 41 or 42, wherein the power provided to the first heating device is reduced, in particular simultaneously reduced, while the power provided to the second heating device is increased.

[0348] Example 44: The method according to any one of examples 41 to 43, wherein the power provided to the first heating device is reduced at the occurrence of the user inhalation to a power level below a power level supplied to the first heating device before the occurrence of the user inhalation.

[0349] Example 45: The method according to any one of examples 41 to 44, wherein the supply of electrical power to the first heating device is stopped or deactivated at the occurrence of the user inhalation.

[0350] Example 46: The method according to any one of examples 41 to 45, wherein the power provided to the second heating device is increased at the occurrence of the user inhalation from an initial power level to a nominal power level during the occurrence of the user inhalation.

[0351] Example 47: The method according to any one of examples 41 to 46, wherein the supply of electrical power to the second heating device is stopped or deactivated before the occurrence of the user inhalation, and increased to a nominal power level during the occurrence of the user inhalation.

[0352] Example 48: The method according to any one of examples 41 to 47, further comprising:FTR4067

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[0354] activating the supply of electrical power to the second heating device at the occurrence of the user inhalation, at the start of the user inhalation, or upon detecting the occurrence of the user inhalation.

[0355] Example 49: The method according to any one of examples 41 to 48, further comprising: activating, during the occurrence of the user inhalation, the supply of electrical power to the first heating device upon reaching a nominal power level of the power supplied to the second heating device.

[0356] Example 50: The method according to any one of examples 41 to 49, further comprising: increasing, during the occurrence of the user inhalation, the power provided to the first heating device upon reaching a nominal power level of the power supplied to the second heating device.

[0357] Example 51 : The method according to example 49 or 50, wherein the power provided to the first heating device is increased during the occurrence of the user inhalation to a power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0358] Example 52: The method according to any one of examples 49 to 51 , wherein the power provided to the first heating device is increased during the occurrence of the user inhalation to a power level exceeding a power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0359] Example 53: The method according to the preceding example, further comprising: reducing the power provided to the first heating device towards an end of the user inhalation or upon termination of the user inhalation.

[0360] Example 54: The method according to the preceding example, wherein the power supplied to the first heating device is reduced to substantially the same power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0361] Example 55: The method according to any one of examples 41 to 54, further comprising: reducing the power supplied to the first heating device after termination of the user inhalation.

[0362] Example 56: The method according to the preceding example, wherein the power supplied to the first heating device is reduced after termination of the user inhalation to a power level below a power level, at which the first heating was operated before the occurrence of the user inhalation.

[0363] Example 57: The method according to the preceding example, further comprising: increasing the power supplied to the first heating device to the power level, at which the first heating device was operated before the occurrence of the user inhalation.

[0364] Example 58: The method according to any one of examples 41 to 57, further comprising:FTR4067

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[0366] decreasing the power provided to the second heating device towards an end of the user inhalation.

[0367] Example 59: The method according to any one of examples 41 to 58, further comprising: reducing the power supplied to the second heating device from the nominal power level to a final power level at the end of the user inhalation.

[0368] Example 60: The method according to the preceding example, wherein the final power level is between an initial power level of the power supplied to the second heating device at the start of the user inhalation and the nominal power level supplied to the second heating device during the user inhalation.

[0369] Example 61 : The method according to any one of examples 41 to 60, further comprising: deactivating the supply of electrical power to the second heating device upon termination of the user inhalation or upon detecting termination of the user inhalation.

[0370] Examples will now be further described with reference to the figures in which:

[0371] Figure 1 shows an aerosol-forming system comprising an aerosol-forming device;

[0372] Figure 2 shows an aerosol-forming article;

[0373] Figure 3 shows an aerosol-forming article;

[0374] Figure 4 shows a schematic exploded view of a heating module for an aerosol-forming device;

[0375] Figure 5 shows a schematic exploded view of a heating module and heating chamber for an aerosol-forming device;

[0376] Figure 6 shows a schematic exploded view of a heating module for an aerosol-forming device;

[0377] Figure 7 shows a cross-sectional view of a heater module and a second heating device for an aerosol-forming device;

[0378] Figure 8 illustrates an airflow path through the aerosol-forming device;

[0379] Figure 9 illustrates an electric circuitry connecting a power source, a first heating device and a second heating device of an aerosol-forming device;

[0380] Figure 10 illustrates the evolution or distribution of electric power between a first heating device and a second heating device of an aerosol-forming device; and

[0381] Figure 11 shows a flow chart illustrating a method of controlling an aerosol-forming device or system.

[0382] Herein, identical reference numerals are used, where possible, to designate identical elements that are common to the figures. Also, the images in the drawings are simplified and schematic for illustration purposes and may not be depicted true to scale.

[0383] The present disclosure shows and describes several embodiments which may comprise alternative or supplementary solutions for specific cases or considerations. However, it is notedFTR4067

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[0385] that the present disclosure pertains to a complete device which may comprise any combination of features described herein. In particular, Figures 1 to 11 show and illustrate exemplary aerosolforming systems, aerosol-forming devices and / or various components, elements, and features thereof. While some of Figures 1 to 11 may show some elements or components in greater detail and according to an exemplary embodiment, the variations, examples and embodiments of Figures 1 to 11 can be combined with each other. Especially, it is noted that any of the features of any of the described embodiments may be freely combined with any other features of any other embodiments of the present disclosure. The disclosure is presented in embodiments for explanatory purposes only, and the presentation as specific embodiments does not mean that the features of one embodiment may not be complementary to other features, for example of other embodiments.

[0386] In the following, it can be mutually referred to any of Figures 1 to 11 which each show and illustrate exemplary aerosol-forming systems, aerosol-forming devices, one or more components, one or more features or one or more functions thereof.

[0387] Figure 1 shows an aerosol-forming system 4 for generating aerosol, for example for consumption or inhalation by a user in one or more usage sessions. The system 4 may comprise an aerosol-forming device 1 or aerosol-generating device 1 for generating aerosol and optionally a companion device 3 for at least partially receiving the aerosol-forming device 1. The companion device 3 may be a charging device for charging the aerosol-forming device 1 and / or an energy storage 15 or battery thereof.

[0388] The aerosol-forming device 1 may comprise an insertion opening for at least partially inserting an aerosol-forming article or aerosol-generating article 20, which is explained in more detail below with reference to Figures 2 and 3. The aerosol-forming article 20 may comprise an aerosol-forming substrate 23, such as a tobacco containing substrate and / or other active ingredient.

[0389] The aerosol-forming device 1 may further include processing circuitry or control circuitry 5, for example with at least one processor, microcontroller or controller 17. For generating aerosol during use or consumption of the aerosol-forming article 20, the aerosol-forming device 1 may comprise a first heating device 6a, which may also be referred to herein as heating device 6a of the aerosol-forming device 1 or system 4, arranged at a heating chamber 30 of the aerosolforming device 1. The heating chamber 30 may comprise or define a heating volume 30a. As will be explained in greater detail hereinbelow, the heating chamber 30 and / or heating volume 30a can be sized and shaped to accommodate or receive at least a part of the aerosol-forming article 20 to heat the substrate 23.

[0390] The first heating device 6a can be configured to perform a first heating operation to heat the substrate 23. For example, the first heating device 6a may be configured to heat the substrateFTR4067

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[0392] 23 or article 20 by or based on conductive heating in a continuous heating operation during a usage session. This can include pulsed operation of the first heating device 6a, and for example control thereof based on pulse width modulation. Also, continuous operation of the first heating device does not exclude that the power supply to the first heating device 6a is at least temporarily reduced or stopped completely during a usage session and / or during a user inhalation performed in the course of a usage session.

[0393] To heat the aerosol-forming article 20 or substrate 23, the first heating device 6a can comprise at least one, preferably two heating elements 6, 7 or a heater device for applying heat to at least a portion of the aerosol-forming substrate 23 and / or at least a part of the aerosolforming article 20. Instead of the heating element 6, 7, a non-heat or non-thermal aerosolization device can be used, for example an ultrasonic device (not shown) may also be used to generate aerosol from the aerosol-forming article.

[0394] In particular, the heating device 6a can comprise two opposing heating elements 6, 7, which are spaced apart from each other to form the heating volume 30a therebetween, and to receive the aerosol-forming article 20 for aerosol consumption.

[0395] The control circuitry 5 and / or the processor 17 may be configured to control actuation, activation and / or deactivation of the first heating device 6a and / or of the heating elements 6, 7.

[0396] In the following, heating elements 6, 7 will be described with a focus on resistive heating elements 6, 7, also referred to herein as Joule-type heating elements. However, the first heating device 6a does not necessarily have to be a resistive / Joule-type heater heating device, but other heating means or approaches can be used, as also described herein.

[0397] The aerosol-forming device 1 exemplary shown in Figure 1 may comprise a second heating device 70, which can also be referred to herein as upstream heating device, arranged upstream of the heating chamber 30 and in thermal contact with an upstream airflow path 40a. The second heating device 70 may be optional only and may provide supplementary or indirect heating of the article 20 or substrate 23. The upstream airflow path 40a is arranged upstream of the heating chamber 30 or heating volume 30a, and fluidly connected or coupled to a surrounding, exterior or external environment of the aerosol-forming device 1 via one or more air inlets 46, also referred to herein as main air inlet 46 or device air inlet 46. When a user performs a user inhalation, air can be drawn by the user through the optional mouthpiece 901 or an end of the device 1, wherein the mouthpiece 901 or end of the device 1 can be fluidly coupled to the upstream airflow path 40a and air inlet 46, such that fresh air is drawn via the air inlet 46 through the upstream airflow path 40a and towards the second heating device 70, the heating chamber 30 and / or the heating volume 30a. As will be described in greater detail hereinbelow with reference to Figure 8, for example, the upstream airflow path 40a may be a section or part of a complex or multi-section airflow path structure in the aerosol-forming device 1.FTR4067

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[0399] As the second heating device 70 is in thermal contact with the upstream airflow path 40a, the second heating device 70 can heat the airflow towards the heating chamber 30 and aerosolforming article 20.

[0400] Also, since the second heating device 70 as well as the first heating device 6a are subject to a changes in the airflow caused by the user inhalation, a temperature or change in the temperature of one or both the first heating device 6a and second heating device 70 can be used by the control circuitry 5 to detect one or more of a start, onset, occurrence, duration, end and termination of a user inhalation.

[0401] The second heating device 70 can be configured to perform a second heating operation, which may differ from the first heating operation performed by the first heating device 6a. For example, the first heating device 6a may be configured to provide a continuous heating to the aerosol-forming article 20 or substrate 23 during a usage session, and the second heating device 70 may be configured for a puff-on-demand heating, which can mean that the second heating device 70 can be activated, operated and / or powered by the control circuitry 5 in accordance or correspondence with occurrence of a user inhalation or puff.

[0402] Further, the second heating device 70 may be particularly configured to heat the aerosolforming article 20 and / or substrate 23 based on convection. This can mean that the second heating device 70 is configured to heat the airflow in the upstream airflow path 40a towards the heating chamber 30 and indirectly heat the aerosol-forming substrate 23 or article 20 via the heated airflow. Therefore, the second heating device 70 may also be referred to herein as upstream heating device 70 or convective heater assembly 70. In a non-limiting example, the second heating device 70 may include at least one resistive heating element 71 to heat the airflow in the airflow path 40a. Other heating means or elements can be used instead or in addition. Details of an exemplary second heating device 70 with resistive heating element 71 is shown in Figure 7.

[0403] For powering the first heating device 6a, the at least one heating element 6, 7, and / or the second heating device 70 with electrical power, the aerosol-forming device 1 may further comprise at least one energy storage 15 or power source 15, for example in the form of a removable and / or rechargeable battery, for storing electrical energy or power.

[0404] The control circuitry 5 can be configured to control one or more of the energy storage 15 or power source 15, the first heating device 6a, the at least one heating element 6, 7, and the second heating device 70, for example to heat the aerosol-forming substrate 23 or article 20 in a usage session. In particular, the control circuitry 5 can be configured to control a supply of electrical power from the energy source 15 to the first heating device 6a and / or the second heating device 70, thereby controlling the heating, a heating operation, activation and / or deactivation of the first heating device 6a and / or the second heating device 70.FTR4067

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[0406] Both the aerosol-forming device 1 and the companion device 3 may each comprise an energy storage 15, 15a and the energy storage 15, 15a may be electrically coupled to the respective device 1, 3. In particular, energy storages 15, 15a may be removably couplable to the aerosol-forming device 1 and / or the companion device 3. In other words, energy storages 15, 15a may be a replaceable energy storages or batteries. The connection between the energy storages 15, 15a and the respective devices 1 , 3 may be configured so that the devices 1 , 3 may be run by electrical energy provided by the respective energy storage 15, 15a. Additionally, the connection between the energy storages 15, 15a and the aerosol-forming device 1 and / or the companion device 3 may be configured so that data may be transmitted between the processing or control circuitries of the aerosol-forming device 1 and / or the companion device 3 and the energy storages 15, 15a.

[0407] The aerosol-forming device 1 may further comprise at least one electrical connector 12 for coupling to a corresponding at least one electrical connector 13 of the companion device 3 and / or an electrical connector of an external power supply (not shown), e.g., a USB connector with a USB charger. In an example, energy storage 15 of the aerosol-forming device 1 may be charged based on coupling the device 1 to the companion device 3, for example based on at least partly inserting the device 1 into a compartment or recess of the companion device 3. Upon mechanically coupling the devices 1, 3, an electrical connection between the one or more electrical connectors 12 of the aerosol-forming device 1 may be coupled with the one or more electrical connectors 13 of the companion device 3 to charge the energy storage 15 of the aerosolforming device 1 via the energy storage 15a of the companion device 3. The energy storage 15a of the companion device 3 can, for example, be re-charged via connection to a main power supply, e.g., a USB charger. Any of the charging processes can also be performed wirelessly.

[0408] The aerosol-forming device 1 may further comprise a communications arrangement 9 or communication circuitry 9 with one or more communications interfaces 10 for communicatively coupling the aerosol-forming device 1 with the companion device 3, server, smartphone or other devices, for example, via an Internet connection, a wireless LAN connection, a WiFi connection, a Bluetooth connection, a mobile phone network, a mobile data connection for example but not limited to a 3G / 4G / 5G connection, an edge connection, an LTE connection, a BUS connection, a wireless connection, a wired connection, an optical data connection such as but not limited to IrDa, a radio connection, a near field connection, and / or an loT connection.

[0409] The aerosol-forming device 1 may further comprise a data storage 11 or memory for storing information, program code or data. Data storage 11 may also store collected values of sensors and / or one or more mathematical functions or formulas, software and computer instructions that can be executed by the control circuitry 5 and / or processor 17. One or more sensors 16 may be arranged on, at or in the aerosol-forming device 1 or the companion device 3 to collect data. OneFTR4067

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[0411] or more of the sensors 16 may for example include one or more temperature sensors, one or more strain sensors, one or more puff sensors, one or more flow sensors, one or more pressure sensors, one or more accelerometers or any other suitable sensors.

[0412] The aerosol-forming device 1 may further comprise user interface components, for example comprising an input element or input device 19, for example in the form of a pushbutton, touch display or a capacitive button. The input device 19 may be used as a power button to activate or deactivate the first heating device 6a and / or the second heating device 70 thereby to activate or deactivate the aerosol-forming device 1.

[0413] Upon activation of the aerosol-forming device 1, the first heating device 6a and optionally the second heating device 70 may be activated and heat may be applied to at least a part of the aerosol-forming article 20, such that aerosol can be generated for consumption or inhalation by the user, for example in a usage session. The actual control or operation of the first heating device 6a and the second heating device 70 will be described in more detail hereinbelow, for example with reference to Figures 9 and 10.

[0414] The aerosol-generating device 1 and / or the companion device 3 may each comprise one or more output elements, such as a display device 18 and / or one or more LEDs, for outputting a signal and / or displaying information to a user, for example a user interface such as a GUI, or haptic and acoustic data output devices. The display device 18 may be, for example, a touchscreen and may therefore be configured as both an output and an input element.

[0415] Figure 2 shows three different views of an exemplary aerosol-forming article 20, or consumable, which may be used with the aerosol-forming device 1 of Figure 1 or any of the other figures. In the top left, an end view is shown. Bottom left shows a perspective view, and the right side of Figure 2 shows a side view of the aerosol-forming article 20. A further detailed view of the aerosol-forming article 20 of Figure 2 is shown in Figure 3, which shows a perspective view at the top of Figure 3 and a cross-sectional view along a longitudinal axis A-A at the bottom of Figure 3.

[0416] Although the present disclosure is applicable to conventional and not limited in use of rectangular parallelepiped shaped aerosol-forming articles, Figures 2 and 3 and many other Figures illustrate an aerosol-forming article 20 that may have a flat or planar shape. Other shapes or geometries of the aerosol-forming article 20 are possible and encompassed by the present disclosure.

[0417] The aerosol-forming article shown in Figures 2 and 3, for example, can have the basic shape or foot-print of a rectangle, optionally with rounded corners. For instance, the aerosolforming article 20 may be a cuboid or parallelepiped or rectangular parallelepiped, optionally with rounded corners. It may have a length L which is greater than its width W, which is in turn greater than its thickness T.FTR4067

[0418] 56 / 80

[0419] For example, the length L of the aerosol-forming article 20 may be from 20 mm to 40 mm, for example from 25 mm to 35 mm. In a non-limiting example, the length L of the aerosol-forming article 20 may be 30 mm. The width W of the aerosol-forming article 20 may be from 7 mm to 15 mm, for example from 9 mm to 13 mm. In a non-limiting example, the width W of the aerosolforming article 20 may be 11 mm. The thickness T of the aerosol-forming article 20 may be from 1 mm to 10 mm, for example 2 mm to 5 mm, for example from 2.5 mm to 4 mm. In a non-limiting example, the thickness T of the aerosol-forming article 20 may be 3.1 mm.

[0420] The aerosol-forming article 20 may comprise a frame 21 and an aerosol-forming substrate 23, which may be arranged in a centre section of the article 20 The centre section of the article 20 may also be referred to as central section or middle section of the article 20. The frame 21 may comprise or be made of a cellulose fibre material, for example a cardboard material. The frame 21 may define the circumference or perimeter of the aerosol-forming article 20 along the edges and / or corners.

[0421] The aerosol-forming article 20 comprises two opposing sides, surfaces or main faces 20a, 20b that make up the majority of the surface of the aerosol-forming article 20. The main faces or surfaces 20a, 20b may comprise or be made of a cover sheet, which may comprise paper-based material, for example rolling paper, which may be fixed to the frame 21 and, together with the frame 21, may define a substrate chamber or cavity 22, which may be filled with any type of aerosol-forming substrate or capsule mentioned herein, or a combination of one or more substrate and a capsule. In particular, solid substrate material may be used.

[0422] The present disclosure provides an aerosol-forming device 1 which may be configured to use such an aerosol-forming article 20. In particular, the heating chamber 30 and / or heating volume 30a of the aerosol-forming device 1 may be configured, shaped and arranged to removably accommodate or receive a rectangular parallelepiped shaped aerosol-forming article 20, as described herein. Optionally, the heating chamber 30 and / or heating volume 30a may be defined by or comprise a heating module 34 configured to removably accommodate such an aerosol-forming article 20 with predominantly planar form factor, maximizing the heating efficiency and increasing the consumable extraction, without quickly depleting the aerosol. To do so, a full contact between the at least one heating element 6, 7 of the first heating device 6a and the aerosol-forming article 20 may be ensured during the heating phase or usage session. As will be shown below, substantially flat or planar heating elements 6, 7 may provide the benefit of keeping a high ratio of surface heated versus substrate volume, which, in turn, can provide for a faster and more homogeneous substrate heating.

[0423] The aerosol-forming article 20 may also comprise an airflow path through the frame 21 and the substrate 23 in the substrate chamber. A detailed view of the aerosol-forming article 20 is given in Figure 3. The aerosol-forming article 20 may be predominantly flat or planar. It may beFTR4067

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[0425] shaped as a rectangular parallelepiped or cuboid. It may comprise the frame 21 or consumable frame 21 having a cavity 22 designed to accommodate the aerosol-forming substrate 23.

[0426] The aerosol-forming article 20 can have a substantially rectangular parallelepiped shape defining two opposing main faces 20a, 20b, which constitute the majority of the surface of the article 20. The aerosol-forming article 20 further defines two opposing side faces 20e, 20f or lateral faces 20e, 20f. The two opposing side faces or lateral faces 20e, 20f may extend parallel to a longitudinal direction of the aerosol-forming article 20. The aerosol-forming article 20 further defines or comprises two opposing smallest faces or surfaces 20c, 20d, which oppose each other in longitudinal direction of the aerosol-forming article 20.

[0427] On the sides or main faces 20a, 20b of the cavity 22, where no frame 21 may be located, the cavity 22 may be closed off from the outside environment by a sheet of cellulose fiber material, for example paper or rolling paper, or paper-like material. Such a sheet may be provided on both sides of the aerosol-forming article 20.

[0428] The frame 21 or article 20 may further comprise a consumable air inlet 24 arranged at one of the smallest faces 20c and an air or aerosol outlet 25 arranged at the opposite smallest face 20d, which may be arranged substantially in-axis with a direction of longitudinal extension of the aerosol-forming article 20 at the smallest faces 20c, 20d. Accordingly, the air inlet 24 and the aerosol outlet 25 can define a longitudinal direction or axis of the aerosol-forming article 20.

[0429] The air inlet 24 and the air outlet 25 may be arranged at the smallest opposing faces or surfaces 20c, 20d of the aerosol-forming article 2. The air inlet 24 and the air outlet 25 may be fluidically connected to a consumable air inlet channel 26 and a consumable air outlet channel 27, respectively. These channels 26, 27 may be configured to be in fluid communication with the consumable cavity 22.

[0430] The air inlet 24, the air inlet channel 26, the air outlet channel 27 and the air or aerosol outlet 25 each may have a cross-section shaped to correspond in surface area and ratio with the cross-section of the aerosol-forming article 20 and also the substrate 23. For example, the crosssection of the air inlet 24, the air inlet channel 26, the air outlet channel 27 and the air or aerosol outlet 25 is smaller than the cross-section of the aerosol-forming article 20, but the shape of the cross sections may be similar to each other. In other words, the air inlet 24, the air inlet channel 26, the air outlet channel 27 and the air outlet 25 may have a rectangular cross-section, optionally with rounded corners. Therefore, the cross-section may be in the shape of an oblong or ovally-shaped or oval-shaped hole. In this way, the air flowing through the airflow path provided by this cross-section may enter and stream through the similarly arranged substrate 23 in an optimal way. The cross-section as used herein may be perpendicular to a longitudinal axis of the aerosolforming article 20 and / or the direction of the airflow path through the aerosol-forming article 20.FTR4067

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[0432] An exemplary heating concept for the aerosol-forming article 20 as described above is shown in Figure 4 and subsequent Figures. The aerosol-forming device 1 can optionally comprise a heating module 34, as shown in Figure 4. The heating module 34, also referred to as heater module 34, may comprise at least part of or the entire first heating device 6a. In particular, the heating module 34 may comprise the two opposing heating elements 6, 7 of the first heating device 6a, for example substantially flat or planar heating elements 6, 7, which may be arranged parallel and opposite to each other, for example in a sandwich configuration with the aerosolforming article 20 between them.

[0433] An interior of or the entire heating module 34 may define the heating chamber 30. The space between the two heating elements in transverse direction of the device 1 can define the heating volume 30a, which can be a part or subspace of the heating chamber 30. The aerosolforming article 20 may be at least partially or fully inserted into the heating chamber 30 or heating volume 30a. Outer walls of the heating chamber 30 may be defined or provided by an optional heater casing 35, which may also contain the heating elements 6, 7. The heater casing 35 may be arranged in an insulating casing 2 to prevent heat from the heating elements 6, 7 from dissipating and / or reaching the user’s fingers, and for concentrating the heat to the heating chamber 30. The heating elements 6, 7 may be arranged parallel to the two main surfaces 20a, 20b of the aerosol-forming article 20 and define a heating volume therebetween to heat the aerosol-forming substrate 23. The heating elements 6, 7 may be arranged parallel to an inner surface of the heating chamber 30 and / or heater casing 35. The heating chamber 30 may be a substantially cuboid receptacle or space configured to at least partially receive the aerosolforming article 20. It may be defined by at least one side or two parallel, opposite sides configured as a planar cavity surface extending substantially in a plane. The heating element 6 and / or the heating element 7 may extend substantially in a plane parallel to the plane of the planar cavity surface.

[0434] A more detailed view of the heating chamber 30 and heating volume 30a and its arrangement in the aerosol-forming device 1 is shown in Figures 5 and 6. The heating chamber 30 may comprise the two heating elements 6, 7 of the first heating device 6a. The two heating elements 6, 7 are also referred to herein as first heating element 6 and second heating element 7 of the first heating device 6a. The heating elements 6, 7 are arranged in a parallel configuration and opposed to each other. In the specific embodiment shown, the two heating elements 6, 7 may be resistive or Joule-type heaters that transfer heat by heat conduction to the substrate 23 of the aerosol-forming article 20. However, other heating technologies or a combination of different heating technologies may be used.

[0435] The heating chamber 30 may further comprise an insulation casing 2 or insulating casing 2 which may act as an outer first insulation element and may provide an airgap for the airflow. TheFTR4067

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[0437] airgap may have a constant size or cross-section along its extension or may have sections differing in size or cross-section, as will be described with reference to Figure 10. The heating chamber 30 may further comprise the heater casing 35 which may be defined at least at one side by a planar cavity surface extending substantially in a plane and which may be configured to enclose the heating elements 6 and 7, wherein the heating elements 6, 7 may be further held in place by a clamp element 8. The heater casing 35 may have a rectangular cross section and may be configured such to receive at least a portion of an aerosol-forming article 20 that is substantially planar (like the one shown in Figures 2 and 3) and to heat the aerosol-forming article 20 from the outside. In addition, an air space or the heating volume 30a may be provided between the heating elements 6,7 and the inner walls of the heating chamber 30, respectively, that may be thermally insulated.

[0438] The heater casing 35 and / or the heating chamber 30 may have walls with heat-reflecting properties. This may allow to reduce the thermal losses when resistively heating and concentrate the heat within the heating chamber 30 and heating volume 30a, and may also provide for an integrated mechanism for a user being able to firmly hold the aerosol-forming device 1 at a given place without being subjected to unsafe or unpleasant temperatures. The heater casing 35 may also be designed with grooves, channels or any generic means along inner walls of the heating chamber 30 to provide an air flow channel for the air flow through portions of the aerosol-forming device 1, for example a channel that is formed at the longer side faces of the rectangular parallelepiped shape heating chamber 30.

[0439] As shown in Figure 6, the heating elements 6, 7 of the first heating device may be curved or convex towards or in direction of the two opposing main surfaces 20a, 20b of the aerosolforming article. This can ensure good thermal contact. Further optionally, the heating elements 6, 7 may be formed as heating plates or may have a heating structure in the form of heating tracks, as shown in Figure 6. For instance, the heating elements can be substantially flat or planar, which however does not exclude that at least a part of the heating elements is curved or convex towards the substrate 23.

[0440] As further shown in Figure 6, the second heating device 70 can be configured as a convective heater assembly 70, which may be arranged upstream the aerosol-forming article 20, the heating chamber 30, the heating volume 30a and upstream the first heating device 6a, respectively, the heating elements 6, 7 thereof, in order to heat the air entering the aerosolforming article 20.

[0441] Second heating device 70 may comprise at least one resistive heating element 71 or convective heater 71 which may be a resistive component which may transfer heat by convection to the surrounding air. The resistive heating element 71 may be arranged inside a convective heater casing 72 and may be held in place by a bottom cap 75.FTR4067

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[0443] As also shown in Figure 6, the heater casing 35 and / or the insulation casing 2 may be composed by two shells, for example an upper shell and a bottom shell, which may be designed to be engaged and / or combined during assembly. Heater casing 35 and / or insulation casing 2 may be made of a plastic material such as polyether ether ketone (PEEK) and / or polyaryletherketone (PAEK) and / or polyetherimide (PEI), preferably PEEK. Heater casing 35 can also have thermal insulation properties like insulating casing 2, for example having a high thermal resistivity or low thermal conductivity, preferably a thermal conductivity below 1 W / (m • K), more preferably below 0.5 W / (m • K).

[0444] It is also possible that the entire heating module 34 comprising the heating chamber 30 may be removably placed inside the body 800 or device body 800 of the aerosol-forming device 1, for example with electric connection terminals that may be arranged to be in parallel with the main axis of extension or the longitudinal axis of the aerosol-forming device 1, and which can interconnect to corresponding terminals inside the body 800 of device 1. The longitudinal axis of the device 1 may be the same as and / or parallel to the insertion axis or the insertion direction of the aerosol-forming article 20 into the heating chamber 30. The connection may be formed only by the movement of the heating chamber 30 when being inserted into the device body 800.

[0445] As indicated in Figure 5, the aerosol-forming device 1 can include a device body 800 or body 800 and a downstream element 802. The downstream element 802 can also be referred as second housing part or mouthpiece portion 802. Optionally, the mouthpiece 901 may be arranged at the downstream element 802.

[0446] The downstream element 802 may be movably attached to the device body 800, such that the device body 800 and the downstream element 802 can be movable relative to each other between an open position and a use position. In the open position access to the heating chamber 30 and / or heating volume 30a can be provided, such that the aerosol-forming article 20 is removable from or insertable into the heating chamber 30 and / or heating volume 30a. In the closed position, as shown in Figure 5, the heating chamber 30 and / or heating volume 30a is closed and cannot be accessed by the user. Also the heater module 34 may be removed from or inserted into the device body 800 in the open position.

[0447] The downstream element 802 and the device body 800 can be coupled to each other via an interconnection mechanism 802 arranged between the downstream element 802 and the device body 800, and permitting the movement between the open and the use position. Therein, the movement can include a rotational movement, a linear movement, or combination of a rotational and linear movement.

[0448] Figure 7 shows a cross-sectional view of a heater module 34 and a second heating device 70 for an aerosol-forming device 1. The top depiction of Figure 7 shows a top view of the section of the device 1 comprising the heating chamber 30.FTR4067

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[0450] With reference to Figure 7, the heating chamber 30 may be associated with the second heating device 70 or convective heater assembly 70, for example to boost the extraction of the aerosol compounds from the aerosol-forming article 20. The bottom depiction of the Figure shows a lateral or side view of the second heating device 70.

[0451] The second heating device 70 may contribute to the definition of the upstream airflow path 40a and may be arranged upstream the heating chamber 30 and / or heating volume 30a to guarantee a continuous route for the airflow through the aerosol-forming device 1. The air may therefore enter the convective heating assembly 70, be heated, and then enter the heating chamber 30 and / or heating volume 30a with the aerosol-forming article 20. Preferably, the convective heater assembly 70 or second heating device 70 is arranged such that an airflow path from the resistive heating element 71 to the upstream inlet 24 of article 24 is as short as possible, to avoid a drop of temperature to the air after passing the resistive heating element 71. In a variant, it is also possible that the resistive heating element 71 protrudes into the upstream air inlet 24 of the article 20, when the article 20 is in an inserted position.

[0452] The second heating device 70 may include the resistive heating element 71 and a convective heater casing 72, wherein the convective heater casing 72 may have a convective heating chamber 73 configured to receive the resistive heating element 71, without getting in direct contact with inner walls of the convective heating chamber 73. This configuration may define two gaps 74 above and below the heating element 71 (best visible in the lateral cross-sectional view of the bottom of Figure 7) which allows a convective heat exchange between the resistive heating element 71 and the surrounding air passing through the gaps 74. In other words, the gaps 74 may form a part of the airflow channel through the aerosol-forming device 1 leading through the second heating device 70.

[0453] The resistive heating element 71 of the second heating device 70 can be formed as a meandering or serpentine structure, extending in-plane of the resistive heating element 71. Alternatively or additionally, the resistive heating element 71 can comprise at least one strip of a metal sheet, optionally wherein the strip of metal sheet is perforated and / or includes one or more perforation openings or holes. Alternatively or additionally, the resistive heating element 71 can comprise at least one strip of a metal sheet, the at least one strip being bent or formed into a stack of a plurality of serpentine-like formed branches, preferably the branches of the stack spanning between two terminals of the resistive heating element 71.

[0454] Further, a bottom cap 75 can ensure that the second heating device 70 and the heating chamber 30 are held together. Preferably, the convective heater casing 72 is made of a material that has low thermal conductivity, so that a heating of the inner walls of the heater casing 72 is reduced, with the goal to provide the heating energy preferentially or predominantly to the incoming air. For example, preferably, the heater casing 72 is not made of metal, but of aFTR4067

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[0456] thermoplastic with high temperature resistivity and low thermal conductivity, preferably PEEK or PEI.

[0457] The dimensions of the cavity or heating volume 30a provided by the heating chamber 30 may reflect the dimensions of the aerosol-forming article 20 in order to ensure that the article 20 can be inserted to the heating chamber 30 or volume 30a and arranged between heating elements 6,7, although a part of the aerosol-forming article 20 may protrude out of the heating chamber 30 and heating volume 30a. Preferably, the fit should be a light press-fit or a light interference fit with the aerosol-forming article 20 between heating elements 6, 7. For example, the heating chamber 30 and / or heating volume 30a may have a length L3 of from 10 mm to 35 mm, for example of from 15 mm to 30 mm or from 15 mm to 25 mm. This may also be referred to as the insertion depth of the heating chamber 30 and / or heating volume 30a. The heating chamber 30 and / or heating volume 30a may have a width W3 of between 7.2 mm and 15.2 mm, preferably between 9.2 mm and 13.2 mm, more preferably about 11.2 mm. The heating chamber 30 and / or heating volume 30a may have a thickness T3 of between 2 mm and 10 mm, more preferably between 3 mm and 8 mm, even more preferably between 4 mm and 6 mm. These values may pertain to the inside clearances of the heating chamber 30 and / or heating volume 30a in the respective directions. Again, these values are purely exemplary, and any other suitable dimensions may be chosen.

[0458] A benefit of using substantially flat or planar heating elements 6, 7, which can include slightly curved or convex shapes, for the first heating device 6a as described may be the provision of a faster and more homogeneous substrate heating. This may be achieved by the high ratio of surface heated to substrate volume. To further improve aerosol extraction from the aerosolforming article 20, the contact pressure between the aerosol-forming article 20 and the heating element 6, 7 may be increased.

[0459] According to at least some aspects of the present disclosure, heating elements 6, 7 can be provided, that allow to firmly contact a to-be-heated surface of the aerosol-forming article 20 for example at a location where the substrate 23 is located inside the article 20. The heating elements 6, 7 can be resistive or Joule-type heater elements, but other types of heating are also possible, for example inductive heating with elements 6, 7 acting as susceptors. In addition, an air space may be provided around the heating elements 6, 7 to thermally insulate the heating chamber 30 and the heater casing 35.

[0460] Figure 6 also schematically shows a fluidic interconnection element 88, which is also referred to as upstream fluidic interconnection element 88. The fluidic interconnection element 88 may be configured to provide for a fluidic connection between the air inlet 24 of the article 20 and the upstream airflow path 40a. A further or downstream fluidic interconnection element mayFTR4067

[0461] 63 / 80

[0462] connect the aerosol outlet 26 of the article 20 to the downstream element 802 or an airflow path therein.

[0463] The fluidic interconnection element 88 can have a blade or blade structure, which may surround the upstream airflow path 40a. The blade may define an opening of the fluidic interconnection element 88 through which the airflow path 40a can be arranged. The opening may have an oblong shape, for example in cross-section, for example perpendicular to the air flow direction

[0464] The blade structure may be tapered on both the inside and the outside surface of the fluidic interconnection element 88, i.e. both the inside surface contacting the air in the airflow path or channel and the surface directed away from the airflow path or channel. Alternatively, the blade structure may be tapered only or exclusively on the outside surface of the fluidic interconnection element 88. By only tapering the outside surface of the fluidic interconnection element 88 and leaving the inside surfaces completely flat and smooth, the airflow in the airflow path or channel may not be influenced in any way. A tapered inside surface may, otherwise, act as a flow restriction, possibly negatively affecting the airflow. Additionally, by leaving the inside surface of the fluidic interconnection element 88 straight and only tapering the outside surface, when the fluidic interconnection element 88 is inserted into the frame 21 of the aerosol-forming article 20 by penetration, the material of the frame 21 may be only or substantially only displaced by the tapered outside surface, displacing the material in a direction away from the airflow path 40a or channel. In this way, no displaced material of the frame 21 is displaced or otherwise pressured into the airflow path or channel, which would again possibly affect the airflow negatively and impact aerosol formation. This can be avoided by the specific shape of the hollow blade structure as explained herein.

[0465] Figure 8 shows several cross-sections through an aerosol-forming device 1, and illustrates an exemplary airflow through the aerosol-forming device 1. The top of Figure 8 shows a crosssection through heating chamber 30 or module arranged in the aerosol-forming device 1, and the middle and bottom sections of Figure 8 show a cross-section primarily through the heating module 34. It is noted that the airflow path shown and described with reference to Figure 8 is exemplary only. Many variations are possible.

[0466] Via one or more air inlets 46, device inlets 46 or main air inlets 46, air can enter the body 800, downstream element 802 and / or housing of the aerosol-forming device 1. The exemplary airflow path through the aerosol-forming device 1 of Figure 8 may begin with a first airflow path portion 40 beginning at the air inlet 46. The device air inlet 46 may comprise a peripheral gap between the mouthpiece portion 900 and the device body 800. The peripheral gap may be continuous around the entire device 1, or may have several, potentially separate, sections orFTR4067

[0467] 64 / 80

[0468] portions or openings around the device body 800. In another variant, there is one gap on each side between downstream element 802 and device body 800.

[0469] The gap forming the device air inlet 46 may have a diameter or clearance of at most 0.05 mm or at most 0.075 mm or at most 0.1 mm or at most 0.125 mm or at most 0.15 mm or at most 0.175 mm or at most 0.2 mm. The gap or clearance may be provided around a portion of the perimeter or the circumference of the aerosol-forming device 1, the portion for example being at least 50 % or at least 75 % or at least 90 % of the perimeter or the circumference. Alternatively, the device air inlet 46 may be configured as one or more lateral holes or channels. The lateral holes may be placed at the interface of an outer surface of the downstream element 802 and the device body 800. This placement of the device air inlets 46 may present several advantages, as it may allow for easy cleaning of the airflow path to remove obstructions when the mouthpiece 901 is removed, and it may allow to conceal or make the inlets less visible. Finally, obstruction by the hand and / or fingers of the user may be made less likely. That the device air inlet 46 may be hidden may also enhance design aspects, e.g., the device air inlet 46 may be arranged inside a groove, behind a hinge, or behind a snap, or the like.

[0470] The airflow path may proceed in a second airflow path portion 41 , which may be provided by a gap between the insulation casing 2 and the heater casing 35, or through a channel inside the heater casing 35 itself. The insulating casing 2 and the heater casing 35 may have a rectangular parallelepiped shape. This makes several suitable airflow paths possible between these two elements. For example, there may be two parallel flow path portions on two opposite sides of the aerosol-forming article 20. In these, the air may flow parallel to an axis of longitudinal extension of the aerosol-forming article 20 along the larger side surfaces, or there may be two parallel flow path portions at the two smaller side surfaces of the aerosol-forming article 20 or consumable. In the latter option, the air may flow parallel to the axis of longitudinal extension of the aerosol-forming article 20 along the smaller lateral sides. Also, a combination of these flow paths may be used. With the two parallel flow path portions 41 on the smaller side surfaces 20e, 2 Of , and the heater elements 6, 7 arranged to face the larger side surfaces 20a, 20b of the aerosolforming article 20, it is possible to separate a heating of the substrate 23 and a heating of the incoming airflow, such that the air heating is mainly performed by the second heating device 70, and not by the heater elements 6, 7. In case the second heating device 70 is operated on a puffbasis, e.g. is only heated when a puff occurs, this separation of these heating aspects allows to save energy and better control a temperature of the heat departed to the airflow by the second heating device 70.

[0471] Once the airflow reaches the bottom or distal end part of the insulation casing 2, which may mean the part of the insulating casing 2 opposite the mouthpiece 901 , it may then be redirected towards the second heating device 70 that may accommodate the resistive heating element 71.FTR4067

[0472] 65 / 80

[0473] For this, there may be provided a further airflow path portion 48 which leads the air radially or laterally inwards towards the longitudinal central axis of the aerosol-forming device 1. The airflow path from the entry into the second heating device 70 parallel to the longitudinal axis of the device 1 onwards may constitute the upstream airflow path 40a, as described herein, which is exemplary shown as third airflow path portion 42 in Figure 8.

[0474] The air may enter the second heating device 70 and pass along the resistive heating element 71. In one variant, the airflow may change direction from a direction parallel to the longitudinal axis of the aerosol-forming device 1 by approximately 90° to progress towards a center axis or longitudinal axis of the aerosol-forming device 1, and then may change direction again by 90° to pass through the second heating device 70 which may be arranged in parallel with the longitudinal axis of the aerosol-forming device 1. Therefore, the airflow may change flow direction by 180° or make a U-turn between the second airflow path portion 41 and third airflow path portion 42. This U-turn may be the further airflow path portion 48. In another variant, the resistive heating element 71 may be arranged orthogonal to the longitudinal axis of the aerosolforming device 1, and the airflow may pass through the resistive heating element 71 while progressing towards the center axis or longitudinal axis of the aerosol-forming device 1. In this case, the second heating device 70 may be part of or arranged in the further airflow path portion 48. The airflow may then change direction again by 90° to leave the resistive heating element 71 and / or the second heating device 70 to directly enter the aerosol-forming article 20 through air inlet 24, optionally via the upstream fluidic interconnection element 88. The third airflow path portion 42 may then shorten. Two parallel airflow path portions 41 can be fluidically reunited, for example merged or combined, at element or portion 42. This allows for redundancy if one of them is blocked. The parallel arrangement reduces the overall resistance-to-draw.

[0475] The passage of the air through the resistive heating element 71 and / or the second heating device 70 may be particularly relevant because it may allow the air coming from the outside environment and having ambient temperature (passing through airflow path portions 40 and 41) to be heated by the resistive heating element 71 in very close proximity before arriving at the substrate 23. The bottom and / or distal end part of the insulating casing 2, which is directed away from the mouthpiece 901 or inhalation side of the device 1, may be referred to as the convective heating chamber 73, and may be configured with a convective or heat exchange heater placed therein to heat up the air upstream of the article 20. Different configurations of the second heating device 70 and resistive heating element 71 are possible. In general, it may be desirable to use a resistive heating element 71 with a heating surface as large as possible, so that a large air surface may come into contact with the heated surfaces of the resistive heating element 71.

[0476] Figure 9 illustrates the evolution or distribution of electric power between a first heating device 6a and a second heating device 70 of an aerosol-forming device 1. The aerosol-formingFTR4067

[0477] 66 / 80

[0478] device 1 may comprise the same features, functions and elements as described with reference to the foregoing figures.

[0479] Specifically, Figure 9 shows in the top part the electric power or power level 300 (in arbitrary units) supplied to the first heating device 6a by the control circuitry 5 and / or power source 15 as a function of time (in arbitrary units) during a usage session or at least a part thereof. The top part of Figure 9 further illustrates the temperature 330 of the first heating device 6a and / or the heating elements 6, 7 thereof.

[0480] The bottom part of Figure 9 shows the electric power or power level 350 (in arbitrary units) supplied to the second heating device 70 by the control circuitry 5 and / or power source 15 as a function of time (in arbitrary units) during at least a part of a usage session.

[0481] Figure 9 illustrates the exemplary evolution or distribution of power for the first heating device 6a and the second heating device 70 during three exemplary user inhalations 310a, 310b, 310c or puffs 310a, 310b, 310c performed by the user during a usage session.

[0482] As described herein and illustrated in Figure 9, the control circuitry 5 may be configured to operate the first heating device 6a and the second heating device 70 in a coordinated manner during a user inhalation 310a-c and / or during occurrence of a user inhalation 310a-c. This can allow operating the aerosol-forming device 1 in an energy efficient manner, respectively, can allow optimizing or maximizing the heating efficiency of the first heating device 6a and the second heating device 70. This may mean or include that electric losses can be reduced, thereby maximizing the amount of electric energy or power provided by the power source 15 to actually heat the aerosol-forming substrate 23.

[0483] Also, the energy storage 15 or power source 15 may be operated safely to a particular power or energy drawn from the power source 15 per unit time. Exceeding this particular power or energy drawable safely from the power source 15 per unit time, may lead to excessive strain of the power source 15 and increase degradation thereof. Therefore, operating the first heating device and the second heating device 70 in a coordinated manner, as described herein and for example illustrated in Figure 9, can allow reducing or avoiding the strain on and the degradation of the power source 15. For example, this allows to avoid exceeding the maximal continuous discharge current or at least avoid exceeding the maximal peak discharge current of a given battery or battery pack as the power source 15.

[0484] In Figure 9,

[0485]

[0486] denotes the instant in time of the start, onset or initiation of the respective user inhalation 310a-310c, and t2denotes the instant in time of the end, stop or termination of the respective user inhalation 310a-310c. Therein, can be referred to as start time of a user inhalation 310a-c, and t2can be referred to as stop time or termination time of user inhalation 310a-c.FTR4067

[0487] 67 / 80

[0488] To detect occurrence, start, onset or termination of a user inhalation 310a-c, the aerosolforming device 1 may comprise one or more puff sensors, such as for example, one or more flow sensors detecting an airflowthrough the upstream airflow path 40a, one or more pressure sensors detecting changes in the pressure in the airflow path 40a, one or more accelerometer-based puff detectors, one or more acoustic sensors, one or more capacitive sensors or any other type of puff detector or sensor.

[0489] Alternatively or additionally, the control circuitry 5 may be configured determine or detect a user inhalation 310a-c at the aerosol-forming device 1 based on determining a change in a temperature of at least one of the first heating device 6a and the second heating device 70 caused by a change in the airflow through the upstream airflow path 40a resulting from the user inhalation 310a-c, and for example caused by a cooling effect departed by the airflow onto the one or both the first and second heating devices 6a, 70

[0490] The control circuitry 5 may be configured to determine or detect one or more of the user inhalations 310a-c, occurrence of the user inhalations 310a-c, a duration of the user inhalations 310a-c, an onset of the user inhalations 310a-c, an end of the user inhalation 310a-c, and a start of the user inhalations 310a-c at the aerosol-generating device 1 based on determining or detecting one or more changes, decreases or increases in the temperature of at least one of the first heating device 6a and the second heating device 70.

[0491] The control circuitry 5 may be configured to determine or detect one or more of the user inhalations 310a-c, occurrence of the user inhalations 310a-c, a duration of the user inhalations 310a-c, an onset of the user inhalations 310a-c, and a start of the user inhalations 310a-c, and end of the user inhalations at the aerosol-generating device 1 based on determining or detecting one or more changes, increases, or decreases in power consumption of the at least one of the first heating device 6a and the second heating device 70. For example, in case the at least one of the first heating device 6a and the second heating device 70 include a closed-loop temperature control, any cooling effect departed by the incoming air from a user inhalation would result in an increase of the electric power delivered to the at least one of the first heating device 6a and the second heating device 70 to maintain the set temperature value, and the change of power, for example the current supplied to the respective heater, could be analyzed and detected to detect the timing aspects of a user inhalation. Alternatively or additionally, a change in temperature, in particular an increase in temperature of one or both the first heating device 6a and the second heating device 70 may occur when the user stops inhaling, respectively when the user inhalation 310a-c is terminated or ended. Accordingly, the control circuitry 5 can be configured to determine or detect one or more of the user inhalations 310a-c, termination of the user inhalations 310a-c, an end of the user inhalations 310a-c and a duration of the user inhalations 310a-c based onFTR4067

[0492] 68 / 80

[0493] determining or detecting pone or more changes or increases in the temperature of one of or both the first heating device 6a and the second heating device 70.

[0494] Accordingly, the control circuitry 5 can be configured to detect or determine a user inhalation 310a-c at the aerosol-forming device 1 based on one of or both detecting a decrease in the temperature and an increase in the temperature of one of or both the first heating device 6a and the second heating device 70. Hence, the control circuitry 5 can provide the functionality of a puff sensor based on determining changes in the temperature of the first heating device 6a and / or the second heating device 70.

[0495] At least in some configurations or designs, the second heating device 70 may have a lower thermal mass compared to the first heating device 6a. This can be particularly true in case the second heating device 70 is designed or configured as convective heater that can heat the aerosol-forming article 20 or substrate 23 by convective heating. Due to the lower thermal mass, and due to the fact that the second heating device 70 is arranged upstream to the first heating device 6a, the temperature of the second heating device 70 may adapt more quickly to the temperature of the air surrounding or flowing past the second heating device 70, when compared to the first heating device 6a. Hence, a response time for detecting an actual change in the temperature of the second heating device 70, and hence a response time for detecting the user inhalation31 Oa-c, can be reduced by using the second heating device 70 compared to relying on the first heating device 6a, at least in certain designs and configurations of the two heating devices.

[0496] The start time

[0497]

[0498] may, for example, denote the instant in time the control circuitry 5 determines or detects the start, onset or occurrence of the respective user inhalation 31 Oa-c. The stop time t2may denote the instant in time the control circuitry 5 determines or detects termination or end of the respective user inhalation 31 Oa-c.

[0499] As illustrated in Figure 9, the control circuitry 5 can be configured to control the first heating device 6a and the second heating device 70 during occurrence of a user inhalation 31 Oa-c in a coordinated manner. In particular, the control circuitry 5 can be configured to control or operate the power source 15 at the occurrence, start or onset of a user inhalation 31 Oa-c, respectively, at the start time t^ such that at the occurrence, start or onset of a user inhalation 31 Oa-c, the power provided to the first heating device 6a is reduced while the power provided to the second heating device 70 is increased.

[0500] For example, the control circuitry 5 may be configured to detect the start of the user inhalation at time t^ and in response thereto reduce or decrease the power to the first heating device 6a while concurrently increasing the power to the second heating device 70.

[0501] As shown in Figure 9, for the exemplary user inhalations 310a and 310b, the power supply to the first heating device 6a may be stopped completely upon detection of the start of the userFTR4067

[0502] 69 / 80

[0503] inhalation at time trThis may mean that the first heating device 6a can be deactivated upon detection of the start of the user inhalation 310a, b. For the exemplary user inhalation 310c, on the other hand, the power supply to the first heating device 6a is reduced from an initial power level before start of the user inhalation to a power level below the initial power level, but above zero. Accordingly, the first heating device 6a may be operated at a reduced power level compared to the operation before occurrence of the user inhalation 310c.

[0504] Generally, the power to the first heating device 6a may be reduced or stopped gradually or step-wise within a period of time of about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms. Optionally, the power supply to the first heating device 6a may be reduced or deactivated as fast as possible at the start of the user inhalation.

[0505] Generally, a change in the power or power level delivered or supplied to the first heating device 6a and / or the second heating device can be changed, for example deactivated, cut, activated or increased, for example by instructions of the control circuitry 5 within the next sampling period of the heating power control, which can for example be about 1 KHz. Hence, any change, deactivation or activation of the first heating device 6a and / or the second heating device 70 can occur within a minimum time period of about 0.5 ms to about 5 ms, for example about 1 ms.

[0506] In an example, any change, decrease or increase in the power level or power to the first heating device 6a and / or the second heating device 70 can be performed within about 1 ms to about 100ms. This could be embodied by ramping down or up the supply voltage, for example by a pulse width modulation. This could have the advantage of reducing thermal shock to the first and / or second heating device 6a, 70 and avoiding abrupt changes to the current.

[0507] In an example, the power or power level can be adjusted, activated, deactivated or cut by one or more of a switch, a DC-DC converter, and a voltage controller, wherein a capacitor coupled to the first and / or second heating devices 6a, 70 may arranged to gradually discharge or charge, the capacitor optionally being dimensioned in capacity to allow for a ramped-down or ramped-up voltage at a given time constant. The same capacitor may be used for gradually ramping voltage or power up, for example to avoid rapid increase of the heating.

[0508] Simultaneously or concurrently with decreasing or deactivating the power supply to the first heating device 6a, the power supply to the second heating device 70 may be increased upon or in response to detecting the start of the user inhalation 310a-c at time trFor example, the power supply to the second heating device 70 may be increased from an initial power level to a nominal power level. Therein, the initial power level may refer to the power level supplied to the second heating device 70 before occurrence or start of the user inhalation 310a-310c. The initial power level of the second heating device 70 may be zero, which may mean that the second heatingFTR4067

[0509] 70 / 80

[0510] device 70 can be deactivated before start of the user inhalation 310a-c and activated in response to detecting the start of the user inhalation at time tr

[0511] The second heating device 70 may be activated and / or the power supply to the second heating device 70 may be increased, gradually or step-wise, to the nominal power level upon detecting start of the user inhalation 310a-c. The nominal power level may, for example, be reached at the second heating device 70 at a time instant tn, as shown in Figure 9. A time period between start of the user inhalation 310a-c at time h and the time tnto reach the nominal power level can range from about 0.5 ms to about 1 second, for example about 0.5 ms to about 500 ms, in particular about 0.5 to about 200 ms for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms.

[0512] A target temperature of the second heating device, to which it may be heated during occurrence of a user inhalation, may be in a range from about 270°C to about 500°C, for example from about 270°C to about 450°C, or for example from about 270°C to about 320°C, in particular from about 280°C to about 310°C, preferably about 300°C.

[0513] As can be seen in Figure 9, the time to reach the nominal power level at the second heating device 70 can be longer than the time required to deactivate the power supply to the first heating device 6a or to reduce the power level of the first heating device 6a to a level below the power level before occurrence of the user inhalation 310a-310b. Therefore, the first heating device 6a may remain deactivated or remain at the power level below the power level before occurrence of the user inhalation 31 Oa-c during at least a part of the time period, during which the power supply of the second heating device 70 is ramped up to the nominal power level. For instance, the first heating device 6a may remain deactivated or remain powered at the reduced power level for a time period of about 5 ms to about 1 second, for example about 10 ms to about 500 ms, preferably less than 200 ms. Optionally, the first heating device 6a may remain deactivated or remain powered at the reduced power level between h and tn.

[0514] As also shown in Figure 9, before occurrence or start of a user inhalation 31 Oa-c and between consecutive user inhalations 31 Oa-c, the second heating device 70 may be deactivated or not powered. Alternatively, the second heating device 70 may be powered at a power level below or substantially below the nominal power level at times where no user inhalation 31 Oa-c occurs.

[0515] Moreover, the control circuitry 5 may be configured to activate and / or increase, during the occurrence of the user inhalation 31 Oa-c, the supply of electrical power to the first heating device 6a upon determining that the nominal power level of the power supplied to the second heating device 70 is reached at time tn.

[0516] In the exemplary user inhalations 310a and 310c, the electrical power provided to the first heating device 6a is increased upon detecting that the nominal power level is reached at theFTR4067

[0517] 71 / 80

[0518] second heating device 70 at time tnto the same power level, at which the first heating device 6a was operated before the occurrence or start of the user inhalation 310a, 310c. Accordingly, the power level of the electrical power supplied to the first heating device 6a may be increased during at least a part of a duration of the user inhalation 310a, 310c to the same power level as supplied to the first heating device 6a before start of the user inhalation 310a, 310c. For the exemplary user inhalation 310b, the power provided to the first heating device 6a is increased upon detecting that the nominal power level is reached at the second heating device 70 at time tnto a power level exceeding or above the (initial) power level, at which the first heating device 6a was operated before the occurrence of the user inhalation 310b. The power level exceeding the initial power level may be about 5% to about 50%, for example 10% to about 20% higher than the initial power level. Increasing the power supply to the first heating device 6a may allow to compensate the cooling effect of the air drawn by the user during the user inhalation 310a-c through the upstream airflow path and towards or through the heating chamber 30, leading to a potential decrease of the temperature in the heating chamber while the first heating device 6a is not powered at the beginning of the user inhalation .

[0519] The control circuitry 5 can be configured to activate or increase, gradually or step-wise, the supply of electrical power to the first heating device 6a upon detecting that the nominal power level is reached at the second heating device 70 at time tn, for example within a period of time of about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms.

[0520] The control circuitry 5 may further be configured to maintain the first heating device 6a at the power level before occurrence of the user inhalation or at a power level exceeding this power level for substantially the remaining time of the user inhalation 310a-c. In an example, the first heating device 6a may be maintained at the power level before occurrence or start of the user inhalation or at a power level exceeding this power level for a time period between tnand t2of about 10 ms to about 3.5 seconds, for example about 100 ms to about 2.5 seconds, preferably about 500 ms to about 2 seconds.

[0521] As shown for the exemplary user inhalation 310b, upon detecting termination of the user inhalation 310b at time t2, the control circuitry 5 may be configured to reduce the power supply to the first heating device 6a to substantially the same power level supplied to the first heating device 6a before occurrence of the user inhalation 310b. A time period for reducing the power level upon detecting the termination of the user inhalation 310b may be between about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms.

[0522] Further as shown for the exemplary user inhalation 310c, the control circuitry 5 may be configured to reduce the power provided to the first heating device 6a upon termination of the user inhalation at time t2to a power level below the power level provided to the first heating deviceFTR4067

[0523] 72 / 80

[0524] 6a before start of the user inhalation 310c, for example about 5% to about 20% below the initial power level. The power supply to the first heating device 6a may then be ramped up or increased again to substantially the same power level provided to the first heating device 6a before start of the user inhalation 310c within about 0.5 ms to about 200 ms for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms. Optionally, the power to the first heating device may be reduced before termination of the user inhalation 310c, for example towards an end of the user inhalation 310ac.

[0525] As described above, upon detecting start of the user inhalation 310a-c, the power supply to the second heating device 70 can be increased to the nominal power level. Optionally, the control circuitry 5 may be configured to maintain the nominal power level for a predetermined period of time, such as for about 5 ms to about 2 seconds, for example about 10 ms to about 1 second, preferably about 100 ms to about 500 ms.

[0526] Moreover, the control circuitry 5 can be configured to decrease the power provided to the second heating device 70 towards an end of the user inhalation 310a-c. For example, the control circuitry 5 can be configured to reduce the power supplied to the second heating device 70 upon determining that the second heating device has reached the nominal power level at time tnor upon determining that the second heating device 70 has been operated at the nominal power level for said predetermined period of time.

[0527] As shown in Figure 9, the control circuitry 5 can be configured to reduce the power supply to the second heating device 70 from the nominal power level to a final power level at time t2or the end of the user inhalation. Therein, the final power level may be between the initial power level of the power supplied to the second heating device 70 at the start of the user inhalation 310a-c and the nominal power level supplied to the second heating device 70 during the user inhalation. Alternatively, however, the final power level may correspond to the initial power level and / or may be zero Watts.

[0528] For instance, the control circuitry can be configured to reduce the power level to the final power level or deactivate the second heating device 70, for example gradually or step-wise, within a period of time of about 5 ms to about 2 seconds, for example about 10 ms to about 1 second, preferably about 100 ms to about 500 ms, measured from time tn, at which the nominal power level was reached at the second heating device 70.

[0529] The control circuitry 5 can further be configured to deactivate the supply of electrical power to the second heating device 70 upon detecting termination of the user inhalation 310a-c at time t2. For instance, the second heating device 70 may be deactivated upon detecting termination of the user inhalation 310a-c, for example gradually or step-wise, within a period of time of about 0.5 ms to about 200 ms, for example about 1 ms to about 150 ms, preferably within about 1 ms to about 100 ms, measured from time t2.FTR4067

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[0531] Figure 10 illustrates an electric circuitry 400 connecting a power source 15 or energy storage 15, a first heating device 6a and a second heating device 70 of an aerosol-forming device 1. The aerosol-forming device 1 may comprise the same features, functions and elements as described with reference to the foregoing figures. The electronic circuitry 400 shown in Figure 9 may be part of control circuitry 5 of the aerosol-forming device 1. Specifically, Figure 10 shows an exemplary implementation enabling the control circuitry 5 to operate the first heating device 6a and second heating device 70 in coordinated manner, as described with reference to Figure 9 for example.

[0532] In the example of Figure 10, the power source 15 or energy storage 15 is coupled via a common capacitor 370 to the first heating device 6a and to the second heating device 70. The common capacitor 370 may be fed by the power source 15 and may serve as intermediate energy storage for temporarily storing electrical energy from the power source 15 and feeding this energy to the first heating device 6a and / or second heating device 70.

[0533] In the example of Figure 10, the first heating device 6a may be connected to the capacitor 370 via a first DC-DC converter 372, and the second heating device 70 can be connected to the capacitor 370 via a second DC-DC converter 374. Accordingly, the power source 15 may be a common power source 15, for example supplying electrical power via the capacitor 370 and two separate DC-DC converters 372, 374 to the first heating device 6a and the second heating device 70. Between the first and second DC-DC converters 372, 374 and the first and second heating devices 6a, 70, respectively, an additional capacitor (not shown) can be placed to cause a ramping-up and a ramping-down of the heating power that is delivered to the respective heater.

[0534] The DC-DC converts 372, 374 are exemplary only and can refer to or include any component configured to control the power level delivered to the respective heating device 6a, 70, such as for example voltage regulators, switches, buck converters, boost converters, buckboost converters, half-bridge converters, full-bridge converters, voltage multipliers, charge pumps, switched capacitors, or the like. As generally the battery voltage or voltage of the power source 15 can be in a range between 3V and 9V, and the resistivity of the heating elements of the first and second heating devices 6a, 70 can be very low, e.g. less than 1Q, a buck converter can be used that reduces the voltage from the power source 15 applied to the respective first and / or second heating device 6a, 70. By means of the DC-DC converters 372, 374, the first heating device 6a and the second heating device 70 can be operated in coordinated manner, but at different voltages, currents and / or power levels at the same time. In other words, by means of the DC-DC converters 372, 374 different voltage levels, current levels and / or power levels may be provided at the same time to the first heating device 6a and the second heating device 70. For example, the first heating device 6a and the second heating device 70 may have different electrical resistivities or be powered simultaneously at different power levels, which can be takenFTR4067

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[0536] into consideration by the two DC-DC converters 372, 374 or corresponding component of the aerosol-forming device 1.

[0537] Alternatively to the two separate DC-DC converters 372, 374, a single DC-DC converter may be arranged between the power source 15 and the common capacitor 370, such that the same voltage or power level can be applied to the first heating device 6a and the second heating device 70, for example in a pulsed fashion, via a switching element, which can be adjusted by the control circuitry to adjust the power levels for the first heating device 6a and the second heating device 70. Another exemplary possibility may be to have one capacitor that is selectively connectable or couplable to either the first heating device 6a or the second heating device 70 via a two-way switch.

[0538] Figure 11 shows a flow chart illustrating a method of controlling an aerosol-forming device 1 or system comprising a heating chamber 30 configured to receive at least a part of an aerosolforming article 20, an upstream airflow path 40a arranged upstream of the heating chamber 30 and in fluid communication with an external environment of the aerosol-forming device 1, such that air is drawable by a user in one or more user inhalations during a usage session. The aerosolforming device 1 further comprises a first heating device 6a arranged at the heating chamber 30 and configured to perform a first heating operation, and a second heating device 70 arranged in thermal contact with the upstream airflow path 40a and configured to perform a second heating operation. The aerosol-forming device 1 or system 4 can be any one of the devices 1 or systems 4 described herein.

[0539] Generally, the method may comprise controlling, by means of the control circuitry 5, a supply of electrical power from the power source 15 to the first heating device 6a and the second heating device, such that at an occurrence or start of a user inhalation 310a-c, the power provided to the first heating device 6a is reduced while the power provided to the second heating device 70 is increased.

[0540] In a non-limiting example, the method may comprise step S1 of detecting the occurrence or start of the user inhalation 310a-c.

[0541] Step S2 of the exemplary method of Figure 11 may encompass reducing the power provided to the first heating device 6a in response to detecting the occurrence or start of the user inhalation. Optionally, the power supply to the first heating device 6a may be deactivated.

[0542] Further, step S3 of the exemplary method of Figure 11 may encompass increasing the power provided to the second heating device 70 in response to detecting the occurrence or start of the user inhalation. Therein, steps S2 and S3 may be performed simultaneously or concurrently. Further, the power supply to the second heating device 70 may be increased at the occurrence or start of the user inhalation 310a-c from an initial power level to a nominal power level during the occurrence or at least a part of a duration of the user inhalation 310a-c.FTR4067

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[0544] The method may further comprise one or more optional steps. For example, after step S2 and / or S3, the supply of electrical power to the first heating device 6a may be increased or the power supply may be activated upon determining that the nominal power level has been reached by the second heating device 70.

[0545] Further optionally, the power provided to the first heating device 6a may be reduced towards an end of the user inhalation, upon termination of the user inhalation and / or upon detecting termination of the user inhalation 310a-c. For example, in response to determining termination of the user inhalation 310a-c, the first heating device 6a may be deactivated.

[0546] In a further exemplary implementation, the method may comprise decreasing the power provided to the second heating device 70 towards an end of the user inhalation 310a-c. For instance, the power supply to the second heating device may be reduced from the nominal power level to a final power level at the end or time of termination of the user inhalation 310a-c. Optionally, the final power level may be between an initial power level of the power supplied to the second heating device 70 at the start of the user inhalation 310a-c and the nominal power level supplied to the second heating device 70 during at least a part of the user inhalation 310a-c.

[0547] Further optionally, the method may comprise deactivating the supply of electrical power to the second heating device 70 upon termination of the user inhalation 310a-c or upon detecting termination of the user inhalation 310a-c.

[0548] For the purpose of the present description and of the appended claims, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term "about". Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein. In this context, therefore, a number A is understood as A ± 10% of A. Within this context, a number A may be considered to include numerical values that are within general standard error for the measurement of the property that the number A modifies. The number A, in some instances as used in the appended claims, may deviate by the percentages enumerated above provided that the amount by which A deviates does not materially affect the basic and novel characteristic(s) of the claimed invention. Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein.

[0549] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in theFTR4067

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[0551] art and practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

[0552] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Claims

FTR406777 / 80CLAIMS1. An aerosol-forming device, comprising:a heating chamber configured to receive at least a part of an aerosol-forming article; an upstream airflow path arranged upstream of the heating chamber and in fluid communication with an external environment of the aerosol-forming device, such that air is drawable by a user in a user inhalation through the airflow path towards the heating chamber;a first heating device arranged at the heating chamber;a second heating device arranged in thermal contact with the upstream airflow path; a power source for supplying the first heating device and the second heating device with electrical energy, andcontrol circuitry configured to control the first heating device and the second heating device based on controlling a supply of electrical power from the power source to the first heating device and the second heating device, such that at an occurrence of a user inhalation, the power provided to the first heating device is reduced while the power provided to the second heating device is increased,wherein the control circuitry is configured to activate and / or increase, during the occurrence of the user inhalation, the supply of electrical power to the first heating device upon determining that a nominal power level of the power supplied to the second heating device is reached.

2. The aerosol-forming device according to the preceding claim, wherein the control circuitry is further configured to:detect the occurrence of the user inhalation and / or the start of the user inhalation; reduce the power provided to the first heating device in response to detecting the occurrence of the user inhalation; andincrease the power provided to the second heating device in response to detecting the occurrence of the user inhalation.

3. The aerosol-forming device according to any one of the preceding claims, wherein the control circuitry is configured to reduce the power provided to the first heating device at the occurrence of the user inhalation to a power level below a power level of the power supplied to the first heating device before the occurrence of the puff.FTR406778 / 804. The aerosol-forming device according to any one of the preceding claims, wherein the control circuitry is configured to deactivate the supply of electrical power to the first heating device at the occurrence of the user inhalation.

5. The aerosol-forming device according to any one of the preceding claims, wherein the control circuitry is configured to deactivate the supply of electrical power to the second heating device before the occurrence of the user inhalation, and increase the supply of electrical power to a nominal power level during the occurrence of the user inhalation.

6. The aerosol-forming device according to any one of the preceding claims, wherein the control circuitry is configured to activate the supply of electrical power to the second heating device at the occurrence of the user inhalation, at the start of the user inhalation, or upon detecting the occurrence of the user inhalation.

7. The aerosol-forming device according to the preceding claims, wherein the power provided to the first heating device is increased during the occurrence of the user inhalation to a power level, at which the first heating device was operated before the occurrence of the user inhalation.

8. The aerosol-forming device according to any one of the preceding claims, wherein the control circuitry is configured to increase the power provided to the first heating device during the occurrence of the user inhalation to a power level exceeding a power level, at which the first heating device was operated before the occurrence of the user inhalation.

9. The aerosol-forming device according to any one of the preceding claims, wherein the control circuitry is configured to reduce the power provided to the first heating device towards an end of the user inhalation or upon termination of the user inhalation.

10. The aerosol-forming device according to any one of the preceding claims, wherein the control circuitry is configured to reduce, upon determining that the user inhalation has ended, the power supplied to the first heating device to a power level below a power level, at which the first heating was operated before the occurrence of the user inhalation.

11. The aerosol-forming device according to the preceding claim, wherein the control circuitry is configured to increase the power supplied to the first heating device to the power level, at which the first heating device was operated before the occurrence of the user inhalation.FTR406779 / 8012. The aerosol-forming device according to any one of the preceding claims, wherein the control circuitry is configured to decrease the power provided to the second heating device towards an end of the user inhalation.

13. The aerosol-forming device according to any one of the preceding claims, wherein the control circuitry is configured to reduce the power supplied to the second heating device from the nominal power level to a final power level at the end of the user inhalation.

14. The aerosol-forming device according to the preceding claim, wherein the final power level is between an initial power level of the power supplied to the second heating device at the start of the user inhalation and the nominal power level supplied to the second heating device during the user inhalation.

15. An aerosol-forming system comprising the aerosol-forming device according to any one of the preceding examples and one or more of:an aerosol-forming article for generating aerosol; anda companion device for one or more of storing the aerosol-forming device and charging the aerosol-forming device.

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