Aerosol generation device

Abstract

To provide an aerosol-generating device for generating aerosol from an aerosol-generating material.SOLUTION: The aerosol-generating device comprises a heating assembly 100 including one or more heating units 110, 120 arranged to heat, but not burn, the aerosol-generating material in use and a controller for controlling the one or more heating units 110, 120. The controller is programmed such that, during a session of use, at least one of the one or more heating units 110, 120 is powered so as to be heated to a plurality of different temperatures sequentially, and each time that the heating units 110, 120 are heated to a new temperature which is higher than a previous temperature, the new temperature is less than 120°C greater than the previous temperature and the heating units are held at the new temperature for at least 0.5 seconds.SELECTED DRAWING: Figure 1A

Description

Technical Field

[0001] The present invention relates to an aerosol generating device, a method for generating an aerosol using the aerosol generating device, and an aerosol generating system including the aerosol generating device. Background

[0002] Articles such as cigarettes and cigars generate tobacco smoke by burning the tobacco during use. Attempts have been made to provide alternatives to these types of articles that burn tobacco by creating products that release compounds without burning. Devices are known that heat a smoking material without burning or combusting it to volatilize at least one component of the smoking material to form an aerosol that can typically be inhaled. Such devices are sometimes described as "non-combustion heating" devices, or "tobacco heating products" (THP), or "tobacco heating devices". Various different configurations for volatilizing at least one component of a smoking material are known.

[0003] The smoking material may be, for example, tobacco, other non-tobacco products, or a combination such as a blended mixture, and they may or may not contain nicotine. Summary

[0004] According to a first aspect of the present invention, there is provided an aerosol generating device for generating an aerosol from an aerosol generating material. The aerosol generating device comprises a heating assembly including one or more heating units configured to heat the aerosol generating material during use without combustion, and a controller for controlling the one or more heating units. The controller is programmed such that during a use session, at least one of the one or more heating units is powered to be sequentially heated to a plurality of different temperatures, and whenever the heating unit is heated to a new temperature that is higher than the previous temperature, the new temperature is less than 120°C higher than the previous temperature, and the heating unit is held at the new temperature for at least 0.5 seconds. In some embodiments, the heating unit is held at the new temperature for at least 1 second, 1.5 seconds, 2 seconds, 3 seconds, 4 seconds, or 5 seconds. In some embodiments, the new temperature is less than 110°C or 100°C higher than the previous temperature.

[0005] In some embodiments, when the previous temperature is 80°C or higher, the new temperature is less than 70°C, less than 60°C, or less than 55°C higher than the previous temperature.

[0006] In some embodiments, the first temperature at which the heating unit is heated and held for at least 0.5 seconds is lower than 120°C, lower than 110°C, or lower than 100°C.

[0007] In some embodiments, the plurality of different temperatures includes at least three different temperatures, at least four different temperatures, or at least five different temperatures.

[0008] In some embodiments, the at least three different temperatures include a first temperature, a second temperature that the heating unit reaches after being held at the first temperature, and a third temperature that the heating unit reaches after being held at the second temperature. In these embodiments, the second temperature is higher than the first temperature. Optionally, the second temperature is less than 60°C higher than the first temperature.

[0009] In some embodiments, the third temperature is higher than the second temperature. Optionally, the third temperature is less than 60 °C higher than the second temperature.

[0010] In some embodiments, the first temperature is 40 °C to 120 °C, or 50 °C to 115 °C, or 60 °C to 110 °C.

[0011] In some embodiments, at least one of the one or more heating units is always at a new temperature that is higher than the previous temperature until the heating unit reaches its maximum operating temperature when heated to the new temperature.

[0012] In some embodiments, the one or more heating units include a first heating unit and a second heating unit. In these embodiments, at least one of the one or more heating units may include the second heating unit. The heating assembly may be configured such that the second heating unit is not heated to a temperature of 80 °C, 90 °C, or 100 °C or higher until after 20 seconds from the start of the use session, or until after 30 seconds from the start of the use session.

[0013] In these embodiments, the heating assembly may be configured such that the first heating unit reaches a temperature of 200 °C to 300 °C, or 210 °C to 280 °C, or 220 °C to 260 °C within 20 seconds, or within 10 seconds, or within 5 seconds from the start of the use session.

[0014] In some embodiments, each heating unit of the heating assembly comprises a coil. In these embodiments, each heating unit of the heating assembly may be an induction heating unit comprising a susceptor heating element, and the coil may be configured to be an inductor element for supplying a varying magnetic field to the susceptor heating element.

[0015] In other embodiments, each heating unit of the heating assembly is a resistance heating unit.

[0016] In some embodiments, the aerosol generating device is a tobacco heating product.

[0017] According to a second aspect of the present invention, there is provided an aerosol generating device for generating an aerosol from an aerosol generating material. The aerosol generating device comprises a heating assembly including one or more heating units configured to heat the aerosol generating material during use but not to combust it, and a controller for controlling the one or more heating units. The controller is programmed such that during a usage session, at least one of the one or more heating units is sequentially heated to at least three different temperatures and held at each of the at least three different temperatures for at least 0.5 seconds.

[0018] According to a third aspect of the present invention, there is provided an aerosol generating system comprising the aerosol generating device according to any one of claims 1 to 19 in combination with an aerosol generating article.

[0019] According to a fourth aspect of the present invention, there is provided a method of generating an aerosol from an aerosol generating material using the aerosol generating device according to the first or second aspect. The method includes the step of sequentially reaching a plurality of different temperatures and instructing the heating unit such that whenever the new temperature is higher than the previous temperature, the new temperature is less than 120 °C higher than the previous temperature. The method also includes the step of instructing the heating unit to hold each new temperature for at least 0.5 seconds.

[0020] The features described herein in connection with one aspect of the invention are explicitly disclosed in combination with other aspects, where applicable.

[0021] Further features and advantages of the present invention will become apparent from the following description of the preferred embodiments of the present invention, given by way of example only and with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022]

Figure 1A

Figure 1B

Figure 2A

Figure 2B

Figure 3

Figure 4

Figure 5

[0023] As used herein, "the" may be used, where necessary, to mean "the" or "the or each". In particular, features described in connection with "the at least one heating unit" may be applicable to the first, second, or further heating units (if present). Further, features described in relation to an integer of "first" or "second" may be applicable integers. For example, features described in relation to a "first" or "second" heating unit may be equally applicable to other heating units in different embodiments. Similarly, features described in relation to a "first" or "second" operating mode may be equally applicable to other configured operating modes.

[0024] Generally, a reference to the "first" heating unit of a heating assembly does not indicate that the heating assembly includes more than one heating unit, unless otherwise specified. Rather, a heating assembly comprising a "first" heating unit simply must comprise at least one heating unit. Thus, a heating assembly that includes only one heating unit clearly falls within the definition of a heating assembly comprising a "first" heating unit.

[0025] Similarly, a reference to the "first" and "second" heating units of a heating assembly does not necessarily indicate that the heating assembly includes only two heating units; there may be additional heating units. Rather, in this example, the heating assembly simply must comprise at least the first and second heating units.

[0026] When an event such as reaching a maximum operating temperature is said to occur "within" a given period, the event may occur at any point in time between the start and end of that period.

[0027] When describing "different temperatures" with respect to a single heating unit, it is meant that the single heating unit passes through different temperatures over time such that one temperature sequentially follows another. This is not meant to say that a single heating unit has different temperatures simultaneously in different spatial regions of the heating unit.

[0028] As used herein, the term "aerosol-generating material" includes materials that, when heated, typically provide volatile components in the form of an aerosol. The aerosol-generating material may include any tobacco-containing material, for example, one or more of tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco, or tobacco substitutes. The aerosol-generating material may also include other non-tobacco products, which may or may not contain nicotine depending on the product. The aerosol-generating material may be in the form of, for example, a solid, liquid, gel, or wax. The aerosol-generating material may also be, for example, a combination or blend of several materials. The aerosol-generating material may also sometimes be known as a "smoking material". In a preferred embodiment, the aerosol-generating material is a non-liquid aerosol-generating material. In a particularly preferred embodiment, the non-liquid aerosol-generating material contains tobacco.

[0029] Devices are known that heat an aerosol-generating material without burning or combusting it to volatilize at least one component of the aerosol-generating material to form an aerosol that can typically be inhaled. Such devices are sometimes also described as "aerosol-generating devices", "aerosol supply devices", "non-combustion heating devices", "tobacco heating products", "tobacco heating product devices", or "tobacco heating devices". In a preferred embodiment of the present invention, the aerosol-generating device of the present invention is a tobacco heating product. The non-liquid aerosol-generating material for use with a tobacco heating product contains tobacco.

[0030] Similarly, there are so-called "e-cigarette" devices, which are typically aerosol-generating devices that vaporize an aerosol-generating material in liquid form (which may or may not contain nicotine). The aerosol-generating material may be in the form of a rod, cartridge, or cassette that can be inserted into the device, or may be provided as part of it. A heater for heating and volatilizing the aerosol-generating material may be provided as a "permanent" part of the device.

[0031] An aerosol generation device can receive an article (also referred to as a "smoking article") containing an aerosol generating material for heating. The "article", "aerosol generating article" or "smoking article" in this context is a component that contains or has an aerosol generating material during use, and this component, during use, is heated to volatilize the aerosol generating material and, optionally, other components. The user can insert the article into the aerosol generation device before heating the article to generate an aerosol, and then the user inhales the aerosol. The article may be of a predetermined or specific size configured to be disposed, for example, within a heating chamber of a device sized to receive the article.

[0032] The aerosol generation device of the present invention comprises a heating assembly. The heating assembly comprises one or more heating units, and each heating unit is configured to heat the aerosol generating material during use without combustion.

[0033] A heating unit typically refers to a component configured to receive electrical energy from an electrical energy source and supply thermal energy to the aerosol generating material. The heating unit comprises a heating element. The heating element is typically a material configured to supply heat to the aerosol generating material during use. A heating unit comprising a heating element may also comprise any other necessary components such as a component for converting the electrical energy received by the heating unit. In other examples, the heating element itself may be configured to convert electrical energy into thermal energy.

[0034] The heating unit may comprise a coil. In some examples, the coil is configured to cause heating of at least one conductive heating element during use, such that as a result, thermal energy is conductible from the at least one conductive heating element to the aerosol generating material, thereby causing heating of the aerosol generating material.

[0035] In some examples, the coil is configured to generate a varying magnetic field that penetrates at least one heating element during use, thereby causing inductive heating and / or magnetic hysteresis heating of the at least one heating element. In such configurations, the said or each heating element may be referred to as a "susceptor". A coil configured to generate a varying magnetic field that penetrates at least one conductive heating element during use, thereby causing inductive heating of the at least one conductive heating element, may be referred to as an "induction coil" or an "inductor coil".

[0036] The device may include one or more heating elements, such as one or more conductive heating elements, which may be suitably arranged or arrangeable relative to the coil so as to enable such heating of the one or more heating elements. The one or more heating elements may be in a fixed position relative to the coil. Alternatively, at least one heating element, such as at least one conductive heating element, may be included within an article so as to be inserted into a heating section of the device, the article also comprising an aerosol-forming material and being removable from the heating section after use. Alternatively, both the device and such an article may each comprise at least one heating element, such as at least one conductive heating element, and the coil may be such as to cause heating of the respective one or more heating elements of the device and the article when the article is within the heating section.

[0037] In some examples, the coil is helical. In some examples, the coil surrounds at least a portion of a heating section of a device configured to receive an aerosol-forming material. In some examples, the coil is a helical coil that surrounds at least a portion of the heating section.

[0038] In some examples, the device comprises a conductive heating element that at least partially surrounds the heating section, and the coil is a helical coil that surrounds at least a portion of the conductive heating element. In some examples, the conductive heating element is tubular. In some examples, the coil is an inductor coil.

[0039] In some examples, the heating unit is an induction heating unit. Surprisingly, it has been found by the inventors that the induction heating unit of the aerosol generating device reaches its maximum operating temperature much more rapidly than the corresponding resistive heating element. In a preferred embodiment, the heating assembly is configured such that the first induction heating unit reaches its maximum operating temperature at a rate of at least 100 °C per second. In a particularly preferred embodiment, the heating assembly is configured such that the first induction heating unit reaches the maximum operating temperature at a rate of at least 150 °C per second.

[0040] Induction heating systems can also be advantageous because they can easily control the magnitude of the alternating magnetic field by controlling the power supplied to the heating unit. Furthermore, induction heating does not require a physical connection between the alternating magnetic field source and the heat source, which can increase the design freedom and control over the heating profile and reduce costs.

[0041] In other examples, the heating unit is a resistive heating unit. The resistive heating unit can be composed of a resistive heating element. That is, since the resistive heating element itself converts electrical energy into thermal energy, it is not necessary for the resistive heating unit to include a separate component for converting the electrical energy received by the heating unit.

[0042] Using an electrical resistance heating system can be advantageous because it allows for easier control of the rate of heat generation and easier generation of lower levels of heat compared to using combustion for heat generation. Therefore, using an electrical heating system can provide greater control over the generation of aerosol from the tobacco composition.

[0043] Throughout this specification, reference is made to the temperature of the heating element. It is convenient to be able to also refer to the temperature of the heating element as the temperature of the heating unit comprising the heating element. This does not necessarily mean that the whole of the heating unit is at a given temperature. For example, when referring to the temperature of an induction heating unit, this does not necessarily mean that both the induction element and the susceptor have such a temperature. Rather, in this example, the temperature of the induction heating unit corresponds to the temperature of the heating element configured within the induction heating unit. To avoid misunderstanding, the temperature of the heating element and the temperature of the heating unit can be used interchangeably.

[0044] As used herein, "temperature profile" refers to the variation in the temperature of a material over time. For example, the varying temperature of a heating element measured over the duration of a smoking session can be referred to as the temperature profile of that heating element. The heating element supplies heat to the aerosol-forming material during use to generate an aerosol. Accordingly, the temperature profile of the heating element causes the temperature profile of the aerosol-forming material disposed near the heating element.

[0045] In the aerosol-generating device of the present invention, each heating element of the heating assembly is configured to heat but not combust the aerosol-forming material. The temperature profile of each heating element causes the temperature profile of each associated portion of the aerosol-forming material, although the temperature profile of the heating element and the temperature profile of the associated portion of the aerosol-forming material may not exactly correspond. For example, "bleed" can occur in the form of conduction, convection, and / or radiation of thermal energy from one portion of the aerosol-forming material to another portion, there can be variations in the conduction, convection, and / or radiation of thermal energy from the heating element to the aerosol-forming material, and depending on the heat capacity of the aerosol-forming material, there can be a delay between a change in the temperature profile of the heating element and a change in the temperature profile of the aerosol-forming material.

[0046] The heating assembly also comprises a controller for controlling each heating unit present within the heating assembly. The controller may be a PCB. The controller is configured to control the power supplied to each heating unit and to control the "programmed heating profile" of each heating unit present within the heating assembly. For example, the controller may be programmed to control the current supplied to a plurality of inductors and thereby control the resulting temperature profile of the corresponding inductive heating element. Similar to the relationship between the temperature profile of the heating element and the temperature profile of the aerosol-forming material, the programmed heating profile of the heating element may not exactly correspond to the observed temperature profile of the heating element for the same reasons as above. The temperature programmed by the controller to heat the heating unit may be referred to as the "programmed temperature".

[0047] In some embodiments, the device comprises one or more temperature sensors for detecting the heat of one or more heating elements disposed in the heating assembly. Suitable temperature sensors include thermocouples, thermopiles, or resistance temperature detectors (RTDs). In certain embodiments, the device comprises at least one RTD. In one embodiment, the device comprises a thermocouple disposed on each heating element present within the aerosol-generating device. The temperature data measured by said or each temperature sensor can be communicated to a controller. Further, when the heating element reaches a predetermined temperature, the temperature data can be communicated to the controller, as a result of which the controller can vary the supply of power to the elements within the aerosol-generating device accordingly. The controller preferably comprises a PID controller that uses a control loop feedback mechanism to control the temperature of the heating element based on data supplied from one or more temperature sensors disposed within the device. In a preferred embodiment, the controller comprises a PID controller configured to control the temperature of each heating element based on temperature data supplied from a thermocouple disposed on each of the heating elements.

[0048] As used herein, "puff" refers to a single inhalation by a user of the aerosol generated by the aerosol-generating device.

[0049] In use, the device of the present invention heats the aerosol - generating material to supply an inhalable aerosol. When at least a portion of the aerosol - generating material reaches the minimum operating temperature, the device can be said to be "ready for use", and the user can take a puff containing a satisfactory amount of aerosol. In some embodiments, the device can be ready for use within about 20 seconds, or within 15 seconds, or within 10 seconds after power is supplied to the first heating unit. Preferably, the device is ready for use within about 20 seconds, or within 15 seconds, or within 10 seconds from the start - up of the device. The device may start supplying power to a heating unit, such as the first heating unit, when the device is activated, or may start supplying power to the heating unit after the device is activated. Preferably, the device is configured to start supplying power to the first heating unit after a short time after the start - up of the device, such as at least 1 second, 2 seconds, or 3 seconds after the start - up of the device. Preferably, the device is configured such that power is not supplied to the first heating unit, or to all heating units present within the heating assembly, until at least 2.5 seconds after the start - up of the device. This is advantageous in that it can increase the battery life by avoiding the unintentional activation of the heating unit(s).

[0050] The aerosol - generating device of the present invention can become ready for use more quickly than equivalent aerosol - generating devices known in the art, improving the user experience. Generally, it takes a certain amount of time to transfer sufficient thermal energy from the heating unit to the aerosol - generating material to generate an aerosol, so the point at which the device is ready for use is some time after the first heating unit reaches its maximum operating temperature. Preferably, the device is ready for use within 20 seconds, or within 15 seconds, or within 10 seconds after the first heating unit reaches its maximum operating temperature.

[0051] Furthermore, surprisingly, it has been found that the characteristics of the aerosol produced from the aerosol - generating material can depend on the rate at which the aerosol - generating material is heated. For example, an aerosol produced from an aerosol - generating material heated by a heating unit configured to rapidly change temperature may improve the user experience. In one embodiment where the aerosol - generating material contains menthol, by rapidly increasing the temperature of the heating unit, the rate at which menthol is delivered to the user in the aerosol can be increased, thereby reducing the amount of menthol component that is wasted from static heating (i.e., does not form part of the aerosol inhaled by the user).

[0052] In some embodiments, the user's sensory experience resulting from the aerosol produced by the device is similar to the experience of smoking a combustible paper cigarette, such as a factory - made paper - wrapped cigarette.

[0053] The device may be indicated by an indicator to be ready for use. In a preferred embodiment, the device is configured such that the indicator indicates that the device is ready for use within about 20 seconds, or within 15 seconds, or within 10 seconds after power is supplied to the first heating unit. In a particularly preferred embodiment, the device is configured such that the indicator indicates that the device is ready for use within about 20 seconds, or within 15 seconds, or within 10 seconds from the activation of the device. In another preferred embodiment, the device is configured such that the indicator indicates that the device is ready for use within about 20 seconds, or within 15 seconds, or within 10 seconds after the first heating unit reaches its maximum operating temperature.

[0054] As used herein, "usage session" refers to a single period of use of an aerosol generating device by a user. A usage session begins when power is first supplied to at least one heating unit present within the heating assembly. After a period of time has elapsed since the start of the usage session, the device is ready for use. A usage session ends when power is no longer supplied to any of the heating units within the aerosol generating device. The end of a usage session may coincide with the point at which the aerosol generating article is depleted (the point at which the total particulate matter generated amount (mg) at each puff is considered too low to be acceptable to the user). A session has a plurality of puffs of a single duration. The session may have a duration shorter than 7 minutes, or 6 minutes, or 5 minutes, or 4 minutes 30 seconds, or 4 minutes, or 3 minutes 30 seconds. In some embodiments, the usage session may have a duration of 2 - 5 minutes, or 3 - 4.5 minutes, or 3.5 - 4.5 minutes, or preferably a duration of 4 minutes. A session may be initiated by the user actuating a button or switch of the device, whereby the temperature rise of at least one heating unit begins either at startup or shortly after startup.

[0055] After a period of time has elapsed since the start of the usage session, the device becomes ready for use. The device may include an indicator for indicating to the user when it is time to start inhaling the aerosol from the device. As used herein, an "inhaling session" refers to the period that starts when the device becomes ready for use and / or when the indicator indicates to the user that the device is ready for use, and ends at the end of the usage session. The inhaling session essentially has a shorter duration than the total usage session. An "indicated inhaling session" refers to an inhaling session whose starting point is defined as the point in time when the indicator indicates to the user that the device is ready for use. An "operating temperature inhaling session" refers to an inhaling session whose starting point is defined as the point in time when at least a portion of the aerosol-generating material reaches the minimum operating temperature and the user can perform a satisfactory puff containing a satisfactory amount of aerosol. The indicated inhaling session may or may not be the same as the operating temperature inhaling session. To avoid confusion, the general term "inhaling session" includes both of these session definitions. In this specification, references to an inhaling session can be considered to refer to either the indicated inhaling session or the operating temperature inhaling session, unless otherwise indicated.

[0056] As used herein in relation to a heating element, an "operating temperature" refers to any heating element temperature at which the element can heat the aerosol-generating material without combusting it and produce a sufficient amount of aerosol for a satisfactory puff. The maximum operating temperature of the heating element is the highest temperature that the element reaches during a smoking session. The minimum operating temperature of the heating element refers to the lowest heating element temperature at which the heating element can generate a sufficient amount of aerosol from the aerosol-generating material for a satisfactory puff. If multiple heating elements are present within the aerosol-generating device, each heating element has a related maximum operating temperature. The maximum operating temperature of each heating element may be the same or different for each heating element.

[0057] The heating assembly of the present invention may be configured such that at least one heating unit, such as a first heating unit, reaches a maximum operating temperature of 200°C to 340°C during use.

[0058] In some embodiments, the maximum operating temperature is about 200°C to 300°C, or 210°C to 290°C, preferably 220°C to 280°C, more preferably 230°C to 270°C.

[0059] In some embodiments, the maximum operating temperature is about 245°C to 340°C, or 245°C to 300°C, preferably 250°C to 280°C.

[0060] In some embodiments, the maximum operating temperature is lower than about 340°C, 330°C, 320°C, 310°C, 300°C, or 290°C, or 280°C, or 270°C, or 260°C, or 250°C.

[0061] The term "operating temperature" can also be used in relation to the aerosol-forming material. In this case, the term refers to any temperature of the aerosol-forming material itself at which a sufficient amount of aerosol for satisfactory puffing is generated from the aerosol-forming material. The maximum operating temperature of the aerosol-forming material is the highest temperature reached by any part of the aerosol-forming material during a smoking session. In some embodiments, the maximum operating temperature of the aerosol-forming material is higher than 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, or 270°C. In some embodiments, the maximum operating temperature of the aerosol-forming material is lower than 300°C, 290°C, 280°C, 270°C, 260°C, 250°C, or 240°C. The minimum operating temperature is the lowest temperature of the aerosol-forming material at which a sufficient amount of aerosol is generated from the aerosol-forming material to produce a satisfactory "puff". In some embodiments, the minimum operating temperature of the aerosol-forming material is higher than 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C. In some embodiments, the minimum operating temperature of the aerosol-forming material is lower than 150°C, 140°C, 130°C, or 120°C.

[0062] The heating assembly is configured to operate as described herein. The devices of the present disclosure may be at least partially configured to operate in this manner by a controller of the heating assembly being programmed to operate the device in a plurality of modes. Thus, references herein to the configuration of the device or components thereof of the present invention may, among other features (such as the spatial arrangement of components within the heating assembly), refer to a controller of the heating assembly programmed to operate a device as disclosed herein.

[0063] Aerosol-generating articles (such as tobacco heating articles) for aerosol-generating devices typically contain more moisture and / or aerosol-forming agent than combustible smoking articles in order to promote the formation of aerosol during use. The higher moisture and / or aerosol-forming agent content may increase the risk of condensate accumulation within the aerosol-generating device during use, particularly in locations remote from the heating unit(s). This problem may be more pronounced in devices having an enclosed heating chamber and, in particular, in devices having an external heater, compared to devices with an internal heater (such as a "blade" heater). Without wishing to be bound by theory, it is believed that a greater proportion / surface area of the aerosol-forming material is heated by an externally heated heating assembly, resulting in more aerosol being released compared to devices that heat the aerosol-forming material internally, which leads to more condensation of the aerosol within the device. The object of the present invention is to reduce the amount of condensate accumulating within such a device.

[0064] The inventors have found it advantageous that the programmed heating profile of the present disclosure can be used in a device configured to externally heat an aerosol-generating material in order to provide a desired amount of aerosol to a user while keeping the amount of aerosol that condenses within the device low. In particular, configuring the programmed heating profile of at least one heating unit to heat the substrate in a series of "steps" may help reduce the amount of condensate remaining within the device. Further, the maximum operating temperature of the heating unit may affect the amount of condensate formed, and the lower the maximum operating temperature, the less undesirable condensate may be formed. The difference between the maximum operating temperatures of the heating units within the heating assembly may also affect the amount of condensate formed. Further, the point in time within a usage session at which each heating unit present within the heating assembly reaches its maximum operating temperature may affect the amount of condensate formed.

[0065] According to one aspect of the invention, the controller is programmed such that, during a usage session, at least one of the one or more heating units is sequentially heated to a plurality of different temperatures, and whenever the heating unit is heated to a new temperature that is higher than the previous temperature, the new temperature is less than 130°C higher than the previous temperature and the heating unit is held at the new temperature for at least 0.5 seconds. As used herein, a heating unit being "held" at a new temperature means that the measured temperature of the heating unit has a value within a range of 15%, 10%, 5%, 2%, 1%, or 0.1% of a given temperature for at least 0.5 seconds.

[0066] In some embodiments, the new temperature is less than 120°C, 110°C, 100°C, 90°C, 80°C, 70°C, or 60°C higher than the previous temperature.

[0067] In some embodiments, the heating unit is maintained at the new temperature for at least 1 second, 1.5 seconds, 2 seconds, 3 seconds, 4 seconds, or 5 seconds. As used herein, to “maintain” the heating unit at a given temperature for a given duration means that the controller is programmed to supply power to the heating unit such that the heating unit has a constant programmed temperature throughout that duration. The period during which the heating unit is maintained at a constant programmed temperature may be referred to as the “sojourn time” for convenience. The change in temperature before the sojourn time may be referred to as a “step”.

[0068] Small temperature changes followed by a sojourn time at the new temperature may help reduce the amount of condensate that accumulates in the device. In particular, a series of small temperature increases followed by a sojourn time at each new temperature may result in less undesirable condensation than a single temperature increase with the same overall degree of increase. Without wishing to be bound by theory, this “stepped” approach is thought to extend the production of condensate over a longer period and thus enable its removal by the user who is inhaling through the device. Conversely, a large, rapid temperature increase may result in a large amount of condensation in a short period, such that there may be more condensation present than the user can inhale during such a period.

[0069] In some embodiments, when the previous temperature is 80° C. or higher, the new temperature is less than 70° C. higher than the previous temperature, or less than 60° C. higher, or less than 55° C. higher. In certain embodiments, when the previous temperature is 80° C. or higher, the new temperature is less than 55° C. higher. Reducing the temperature change at high temperatures may help reduce unwanted condensation.

[0070] In some embodiments, two temperatures of the programmed heating profile may differ by less than 50° C., 40° C., 30° C., 20° C., or 10° C.

[0071] In some embodiments, the first temperature at which the heating unit is heated and held for at least 0.5 seconds is less than 120°C, less than 110°C, or lower than 100°C. In some embodiments, the first temperature is higher than 40°C, 50°C, 60°C, 70°C, 80°C, or 90°C. In some embodiments, the first temperature is from 40°C to 120°C, or from 50°C to 115°C, or from 60°C to 110°C, or from 70°C to 105°C. Without wishing to be bound by theory, a high first temperature, such as a temperature higher than 120°C, may be thought to produce a large amount of undesirable condensation in a short period of time, due in part to the rapid volatilization of moisture in the substrate.

[0072] As described above, a more gradual heating may help to reduce undesirable condensation. In certain embodiments, until the heating unit reaches its maximum operating temperature, each new temperature at which the heating unit is heated is higher than the previous temperature. This is sometimes referred to, for convenience, as a "stepwise increase."

[0073] According to another aspect of the invention, the controller is programmed such that during a usage session, at least one of the one or more heating units is sequentially heated to at least three different temperatures and held at each of the at least three different temperatures for at least 0.5 seconds. To avoid misunderstanding, by three different temperatures it is meant that they follow each other in time (i.e., sequentially). This is not to say that the heating unit is heated to three different temperatures in different spatial regions of the heating unit.

[0074] In some embodiments, the heating unit may be heated to more than three different temperatures, such as four different temperatures, five different temperatures, or more than five different temperatures, and held at each temperature for at least 0.5 seconds. The greater the number of different temperatures, the more gradual the increase, and thus the less undesirable condensate.

[0075] The programmed profile may include a first temperature, a second temperature, a third temperature, a fourth temperature, and a fifth temperature, among others. In some embodiments, each temperature is higher than the temperature preceding it. For example, the second temperature is higher than the first temperature, and the third temperature is higher than the second temperature.

[0076] The difference between these temperatures is preferably relatively small. The difference between at least some of the temperatures, or between all of the temperatures, may be less than 60°C, 55°C, or 50°C.

[0077] The heating assembly may be operable in a plurality of modes, such as a first mode and a second mode. The heating assembly may be operable in a maximum of two modes, or may be operable in more than two modes, such as three modes, four modes, or five modes. Each mode may be associated with a predefined heating profile for each heating unit within the heating assembly, such as a programmed heating profile. One or more of the programmed heating profiles may be programmed by the user. In addition to, or instead of, this, one or more of the programmed heating profiles may be programmed by the manufacturer. In these examples, one or more of the programmed heating profiles may be fixed such that the end user cannot change one or more of the programmed heating profiles.

[0078] Each operating mode may be associated with a predetermined duration for the usage session. At least some of the operating modes are associated with different predetermined durations. For example, if the heating assembly is operable in a first mode and a second mode, the duration associated with the first mode (the first predetermined duration of the usage session of the first mode) is different from the duration associated with the second mode (the second predetermined duration of the usage session of the second mode). The first predetermined duration of the usage session of the first mode may be longer or shorter than the second predetermined duration of the usage session of the second mode. Preferably, the first predetermined duration of the usage session of the first mode is longer than the second predetermined duration of the usage session of the second mode.

[0079] Providing an aerosol-generating device, such as a tobacco heating product, having a heating assembly operable in multiple modes is advantageous in that it gives consumers more choices, especially when each mode is associated with a different duration of the usage session. Furthermore, such a device can provide different aerosols with different characteristics because the volatile components in the aerosol-generating material volatilize at different rates and concentrations over different session lengths. Thereby, the user can select a particular mode based on the desired characteristics of the aerosol that can be inhaled, such as the degree of tobacco flavor, nicotine concentration, and aerosol temperature. For example, a mode having a relatively short duration of the usage session may be configured to provide a faster first puff, or a higher nicotine content per puff, or a higher concentration of flavor per puff. Conversely, a mode in which the said or each heating unit rises to a lower temperature may be configured to provide a lower nicotine content per puff, or a more sustained delivery of flavor.

[0080] Each mode may also be associated with the highest temperature to which the said or each heating unit within the heating assembly rises during use. The heating assembly may be configured such that each heating unit reaches the highest operating temperature of the first mode in the first mode and the highest operating temperature of the second mode in the second mode. The highest operating temperature of at least one heating unit of the heating assembly in the first mode may be different from the highest operating temperature of that heating unit in the second mode. For example, the highest operating temperature of the first heating unit in the first mode (referred to herein as the "highest operating temperature of the first mode" of the first heating unit) may be different from the highest operating temperature of the first heating unit in the second mode (referred to herein as the "highest operating temperature of the second mode" of the first heating unit). In some examples, the highest operating temperature of the first mode is higher than the highest operating temperature of the second mode, and in other examples, the highest operating temperature of the first mode is lower than the highest operating temperature of the second mode. The highest operating temperature of the second mode of the first heating unit is preferably higher than the highest operating temperature of the first mode of the first heating unit.

[0081] In embodiments where the said or each heating unit rises to a higher temperature in the second mode, the second mode may be referred to as the "boost" mode. For the first time, aspects of the present invention provide an aerosol generating device operable in a first "normal" mode and a second "boost" mode. The "boost" mode advantageously can provide a faster first puff, or a higher nicotine content per puff, or a higher concentration of flavor per puff. In a preferred embodiment, the heating assembly is configured such that the second mode is associated with a shorter duration use session and a higher highest operating temperature. This may enable a consistent amount of volatile components to be delivered to the user over the use session, and the higher highest operating temperature may result in more rapid depletion of the volatile components from the aerosol generating material, and thus a shorter duration use session is preferred.

[0082] The first usage session duration is preferably longer than the second usage session duration. In some examples, the first and / or second usage sessions may have a duration of at least 2 minutes, 2 minutes 30 seconds, 3 minutes, 3 minutes 30 seconds, 4 minutes, 4 minutes 30 seconds, 5 minutes, 5 minutes 30 seconds, or 6 minutes. In some examples, the first and / or second usage sessions may have a duration of 7 minutes, 6 minutes, 5 minutes 30 seconds, 5 minutes, 4 minutes 30 seconds, or less than 4 minutes. The first usage session duration is preferably 3 to 5 minutes, more preferably 3 minutes 30 seconds to 4 minutes 30 seconds. The second usage session duration is preferably 2 to 4 minutes, more preferably 2 minutes 30 seconds to 3 minutes 30 seconds.

[0083] Each operating mode is also associated with a predetermined duration for the suction session in each mode. The first suction session duration is preferably longer than the second suction session duration. In some examples, the first and / or second suction sessions may have a duration of at least 2 minutes, 2 minutes 30 seconds, 3 minutes, 3 minutes 30 seconds, 4 minutes, 4 minutes 30 seconds, 5 minutes, 5 minutes 30 seconds, or 6 minutes. In some examples, the first and / or second suction sessions may have a duration of 7 minutes, 6 minutes, 5 minutes 30 seconds, 5 minutes, 4 minutes 30 seconds, or less than 4 minutes. The first suction session duration is preferably 3 to 5 minutes, more preferably 3 minutes 30 seconds to 4 minutes 30 seconds. The second suction session duration is preferably 2 to 4 minutes, more preferably 2 minutes 30 seconds to 3 minutes 30 seconds.

[0084] The time until the device is ready for use may vary between operating modes. For example, in embodiments where the second mode has a higher maximum operating temperature, the device may be ready for use at an earlier point in the usage session than in the first mode. In a preferred embodiment, the device is configured such that when operated in the second mode rather than the first mode, the device becomes ready for use more quickly.

[0085] In certain embodiments, the device comprises an indicator and is configured to display to the user when the device is ready for use. In one embodiment, the device is configured such that the point in the usage session at which the indicator indicates to the user that the device is ready for use differs between at least two modes. Preferably, the device is configured such that the point at which the indicator indicates to the user is earlier in a second mode than in a first mode. For example, the device can indicate to the user that in the first mode, aerosol inhalation from the device should commence approximately 20 seconds after the start of the usage session, while in the second mode, it can indicate approximately 10 seconds after the start of the usage session.

[0086] In some embodiments, the heating assembly comprises a plurality of heating units. For example, the heating assembly may comprise two heating units, the first heating unit and the second heating unit as described above. The second heating unit is configured to heat but not combust the aerosol-forming material during use. The second heating unit is controllable by a controller of the heating assembly. The second heating unit is controllable independently of the first heating unit.

[0087] The heating assembly can comprise up to two heating units. In other examples, the heating assembly comprises more than two independently controllable heating units, such as three, four, or five independently controllable heating units.

[0088] In these embodiments, one or more of the heating units may be programmed to have a stepped, programmed heating profile as described above. In certain embodiments, the heating assembly comprises a first heating unit and a second heating unit, and the second heating unit has a stepped, programmed heating profile as described above. In some embodiments, the first heating unit is powered at the start of the session. For example, the heating assembly may be configured such that the first heating unit reaches a temperature of 200°C to 300°C, or 210°C to 280°C, or 220°C to 260°C within 20 seconds, or within 10 seconds, or within 5 seconds after starting the usage session.

[0089] In a preferred embodiment, at least one of the heating units provided in the heating assembly is powered throughout the usage session in at least one mode. In particular, it is preferred that the first heating unit is powered throughout the usage session in the first mode and / or throughout the usage session in the second mode. In a particularly preferred embodiment, the first heating unit is powered throughout the usage session in each operating mode of the device.

[0090] In a preferred embodiment, at least one of the heating units provided in the heating assembly is powered for a period shorter than the entire usage session in at least one mode. This can advantageously enable more economical power usage while maintaining the delivery of an acceptable aerosol to the user. In particular, it is preferred that the second heating unit is powered for a period shorter than the entire usage session in the first mode and / or the entire usage session in the second mode. In a particularly preferred embodiment, the second heating unit is powered for a period shorter than the entire usage session in each operating mode of the device. It is even more preferred that the second heating unit is powered for at least half of the usage session in each mode but for a period shorter than the entire usage session in each mode.

[0091] In some embodiments, power is supplied to the second heating unit after at least 10 seconds, 115 seconds, 20 seconds, 25 seconds, 30 seconds, 35 seconds, 40 seconds, 50 seconds, or 60 seconds have elapsed after the start of the usage session. The slow start time and the stepped programmed heating profile help the second heater to "fade in" to the session and can reduce the generation of unwanted condensate, for example, by extending the period during which condensate is generated.

[0092] In some embodiments, the heating assembly comprises at least a first heating unit and a second heating unit, and the heating assembly is operable in a first mode and a second mode. In this embodiment, the first operating mode may include supplying energy to the first heating unit for a predetermined duration of the first mode, and the second mode may include supplying energy to the first heating unit for a predetermined duration of the second mode. The first mode may also include supplying energy to the second heating unit for a predetermined duration of the first mode, and the second mode may also include supplying energy to the second heating unit for a predetermined duration of the second mode.

[0093] In some embodiments, the predetermined duration of at least one heating unit is the same in each mode. In some embodiments, the predetermined duration of at least one heating unit is different between modes. In a preferred embodiment, the predetermined duration of supplying energy to each heating unit is different between each mode.

[0094] It is clearly conceivable that a heating assembly configured to operate in at least two modes with different session durations may be configured such that energy is supplied to at least one heating unit within the assembly for the same amount of time in both modes. For example, the assembly may be configured to provide a first mode suction session that lasts for 4 minutes and a second mode suction session that lasts for 3 minutes. In this example, if the assembly includes two heating units, the first heating unit may be energized throughout each use session. The second heating unit may be energized only at the last instant of each use session. Thus, in this embodiment, even if the use session in the first mode has a different duration than the use session in the second mode, the assembly is configured to supply power to the second heating unit for the same amount of time in both modes.

[0095] In some embodiments, the predetermined duration of the first mode for supplying energy to the first heating unit is from about 3 minutes to 5 minutes, more preferably from 3 minutes 30 seconds to 4 minutes 30 seconds. The predetermined duration of this first mode may be shorter than 4 minutes 30 seconds, 4 minutes, or 3 minutes 30 seconds. The predetermined duration of this first mode may be longer than 3 minutes, 3 minutes 30 seconds, or 4 minutes.

[0096] In some embodiments, the predetermined duration of the first mode for supplying energy to the second heating unit is from about 2 minutes to 4 minutes, more preferably from 2 minutes 30 seconds to 3 minutes 30 seconds. The predetermined duration of this first mode may be shorter than 4 minutes, 3 minutes 30 seconds, or 3 minutes. The predetermined duration of this first mode may be longer than 2 minutes, 2 minutes 30 seconds, or 3 minutes.

[0097] In some embodiments, the predetermined duration of the second mode for supplying energy to the first heating unit is about 2 to 4 minutes, more preferably 2 minutes 30 seconds to 3 minutes 30 seconds, and most preferably about 3 minutes. The predetermined duration of this second mode may be shorter than 4 minutes or 3 minutes 30 seconds. The predetermined duration of this first mode may be longer than 2 minutes or 2 minutes 30 seconds.

[0098] In some embodiments, the predetermined duration of the second mode for supplying energy to the second heating unit is about 1 minute 30 seconds to 3 minutes, more preferably 2 to 3 minutes, and most preferably about 2 minutes 30 seconds. The predetermined duration of this second mode may be shorter than 3 minutes or 2 minutes 30 seconds. The predetermined duration of this first mode may be longer than 1 minute 90 seconds, 2 minutes, or 2 minutes 30 seconds.

[0099] The heating assembly is preferably configured such that each heating unit present within the heating assembly reaches the maximum operating temperature of the first mode in the first mode and reaches the maximum operating temperature of the second mode in the second mode. For example, the second heating unit can reach the maximum operating temperature of the first mode in the first mode and can reach the maximum operating temperature of the second mode in the second mode. The maximum operating temperature of each heating unit in each mode may be the same or different. For example, the maximum operating temperature of the second heating unit in each mode may be the same as or different from the maximum operating temperature of the first heating unit in each mode.

[0100] The maximum operating temperature of the first mode of the first heating unit may be different from the maximum operating temperature of the second mode of the first heating unit. For example, the maximum operating temperature of the first mode may be higher than the maximum operating temperature of the second mode, or alternatively, the maximum operating temperature of the first mode may be lower than the maximum operating temperature of the second mode. The maximum operating temperature of the second mode of the first heating unit is preferably higher than the maximum operating temperature of the first mode of the first heating unit.

[0101] The maximum operating temperature of the first mode of the second heating unit may be different from the maximum operating temperature of the second mode of the second heating unit. For example, the maximum operating temperature of the first mode may be higher than the maximum operating temperature of the second mode, or alternatively, the maximum operating temperature of the first mode may be lower than the maximum operating temperature of the second mode. It is preferable that the maximum operating temperature of the second mode of the second heating unit is higher than the maximum operating temperature of the first mode of the second heating unit.

[0102] In some embodiments, each heating unit of the heating assembly has a higher maximum operating temperature in the second mode than in the first mode.

[0103] As described above, the maximum operating temperature of the first heating unit may be the same as or different from the maximum operating temperature of the second heating unit. In one embodiment, the maximum operating temperature of the first mode of the first heating unit is substantially the same as the maximum operating temperature of the first mode of the second heating unit. In another embodiment, the maximum operating temperature of the first mode of the first heating unit is different from the maximum operating temperature of the first mode of the second unit. For example, the maximum operating temperature of the first mode of the first heating unit may be higher than the maximum operating temperature of the first mode of the second heating unit, or the maximum operating temperature of the first mode of the first heating unit may be lower than the maximum operating temperature of the first mode of the second heating unit. It is preferable that the maximum operating temperature of the first mode of the first heating unit is substantially the same as the maximum operating temperature of the first mode of the second heating unit. The inventors have found that by configuring the heating assembly such that the maximum operating temperature of the first mode of the first heating unit is substantially the same as the maximum operating temperature of the first mode of the second heating unit, it is possible to reduce the amount of condensate that accumulates in the device during use while still providing an acceptable performance to the user.

[0104] In some examples, the maximum operating temperature of the first heating unit and / or the second heating unit in the first mode is lower than 300°C, 290°C, 280°C, 270°C, 260°C, 250°C, or 240°C. In some examples, the maximum operating temperature of the first heating unit and / or the second heating unit in the first mode is higher than 220°C, 230°C, 240°C, 245°C, 250°C, 255°C, 260°C, 265°C, or 270°C. In some examples, the maximum operating temperature of the first heating unit and / or the second heating unit in the first mode is 240°C to 300°C, or 240°C to 280°C, or 245°C to 270°C. In one embodiment, the maximum operating temperature of the first heating unit in the first mode and the maximum operating temperature of the second heating unit in the first mode are 245°C to 270°C. In another embodiment, the maximum operating temperature of the first heating unit in the first mode and the maximum operating temperature of the second heating unit in the first mode are 220°C to 250°C. Lowering the maximum operating temperature can reduce the amount of undesirable condensate supplied into the device during use.

[0105] In one embodiment, the maximum operating temperature of the first heating unit in the second mode is substantially the same as the maximum operating temperature of the second heating unit in the second mode. In another embodiment, the maximum operating temperature of the first heating unit in the second mode is different from the maximum operating temperature of the second heating unit in the second mode. For example, the maximum operating temperature of the first heating unit in the second mode may be higher than the maximum operating temperature of the second heating unit in the second mode, or the maximum operating temperature of the first heating unit in the second mode may be lower than the maximum operating temperature of the second heating unit in the second mode. It is preferable that the maximum operating temperature of the first heating unit in the second mode is higher than the maximum operating temperature of the second heating unit in the second mode. The inventors have found that by configuring the heating assembly such that the maximum operating temperature of the first heating unit in the second mode is substantially the same as the maximum operating temperature of the second heating unit in the second mode, it is possible to reduce the amount of condensate accumulating in the device during use while still providing an acceptable performance to the user.

[0106] In some examples, the maximum operating temperature of the second mode of the first heating unit and / or the second heating unit is lower than 330°C, 320°C, 310°C, 300°C, 290°C, 280°C, 270°C, or 260°C. In some examples, the maximum operating temperature of the second mode of the first heating unit and / or the second heating unit is higher than 200°C, 220°C, 230°C, 245°C, 250°C, 255°C, 260°C, 265°C, or 270°C. In some examples, the maximum operating temperature of the second mode of the first heating unit and / or the second heating unit is 250°C to 300°C, or 260°C to 290°C. In one embodiment, the maximum operating temperature of the second mode of the first heating unit may be 260°C to 300°C, or 270°C to 290°C. In another embodiment, the maximum operating temperature of the second mode of the first heating unit may be 250°C to 280°C. In one embodiment, the maximum operating temperature of the second mode of the second heating unit may be 240°C to 280°C, or 250°C to 270°C. In another embodiment, the maximum operating temperature of the second mode of the second heating unit may be 220°C to 260°C. Lowering the maximum operating temperature can reduce the amount of undesirable condensate supplied into the device during use. The inventors have confirmed that lowering the maximum operating temperature of the second heating unit can be particularly useful for reducing the amount of undesirable condensate accumulating in the device during use.

[0107] In some embodiments, the maximum temperatures of the first and second heating units in the first operating mode are substantially the same, and the maximum temperatures of the first and second heating units in the second operating mode are substantially the same. Configuring the heating assembly in this way can be further useful for reducing the amount of condensate accumulating in the externally heated device.

[0108] In a further embodiment, the respective maximum temperatures of each heating unit present in the heating assembly are the same in the first operating mode and the same in the second operating mode.

[0109] The aerosol generation device of the present invention comprises a first heating unit and an optional further heating unit, each comprising a heating element. In one embodiment, said or each heating element may be a material that can be heated by the penetration of a variable magnetic field. That is, the aerosol generating material may be heated by induction heating. In this embodiment, the heating unit comprises an inductor (for example, one or more inductor coils), and the device comprises components for passing a variable current, such as an alternating current, through the inductor. The variable current in the inductor generates a variable magnetic field. When the inductor and the heating element are relatively suitably arranged such that the variable magnetic field generated by the inductor penetrates the heating element, one or more eddy currents are generated in the heating element. The heating element has a resistance to the flow of current, and thus when such eddy currents are generated in the object, the eddy currents flow against the electrical resistance of the object, whereby the object is heated by Joule heating. It is convenient that supplying a variable magnetic field to the susceptor can refer to supplying energy to the susceptor.

[0110] An object that can be induction heated is known as a susceptor. When the susceptor contains a ferromagnetic material such as iron, nickel, or cobalt, heat can also be generated by the magnetic hysteresis loss of the susceptor, that is, by the orientation of the magnetic dipoles in the magnetic material changing as a result of aligning with the variable magnetic field. In induction heating, for example, compared to heating by conduction, the heat is generated inside the susceptor, thereby enabling rapid heating. Furthermore, no physical contact is required between the induction heater and the susceptor, thereby greatly increasing the degrees of freedom in terms of structure and application.

[0111] The heating element may be a susceptor. In a preferred embodiment, the susceptor comprises a plurality of heating elements (at least a first induction heating element and a second induction heating element).

[0112] In other embodiments, the heating unit is not limited to an induction heating unit. For example, the first heating unit may be an electric resistance heating unit that can be composed of a resistance heating element. The second heating unit may also be, in addition to or instead of this, an electric resistance heating unit that can be composed of a resistance heating element. The "resistance heating element" means that when an electric current flows through the element, the resistance in the element converts electrical energy into thermal energy, and this thermal energy heats the aerosol-forming substrate. The heating element may be in the form of a resistance wire, mesh, coil, and / or a plurality of wires. The heat source may be a thin film heater.

[0113] The heating element may include a metal or an alloy. Metals are excellent conductors of both electrical and thermal energy. Suitable metals include, but are not limited to, copper, aluminum, platinum, tungsten, gold, silver, and titanium. Suitable alloys include, but are not limited to, nichrome and stainless steel.

[0114] Another aspect of the present invention is an aerosol-generating system comprising an aerosol-generating device as described herein in combination with a smoking article. In a preferred embodiment, the aerosol-generating system comprises a tobacco heating product in combination with a smoking article comprising tobacco. In a suitable embodiment, the tobacco heating product may comprise a heating assembly and an aerosol-generating article as described herein below in connection with the figures.

[0115] Another aspect of the present invention is a method of supplying an aerosol with the aerosol-generating device of the present disclosure. The method includes the step of controlling the said or each heating unit in the heating assembly as described herein.

[0116] Next, the present invention will be described in detail with reference to the figures.

[0117] FIG. 1 shows an induction heating assembly 100 of an aerosol-generating device according to the present invention, and FIG. 1B shows a cross-section of the induction heating assembly 100 of the device.

[0118] The heating assembly 100 has a first end or proximal end or mouth-side end 102 and a second end or distal end 104. In use, the user inhales the formed aerosol from the mouth-side end of the aerosol-generating device. The mouth-side end can be an open end.

[0119] The heating assembly 100 comprises a first induction heating unit 110 and a second induction heating unit 120. The first induction heating unit 110 comprises a first inductor coil 112 and a first heating element 114. The second induction heating unit 120 comprises a second inductor coil 122 and a second heating element 124.

[0120] Figures 1A and 1B show a smoking article 130 received within a susceptor 140. The susceptor 140 forms a first induction heating element 114 and a second induction heating element 124. The susceptor 140 can be formed from any material suitable for induction heating. For example, the susceptor 140 may include a metal. In some embodiments, the susceptor 140 may include a non-ferrous metal such as copper, nickel, titanium, aluminum, tin, or zinc, and / or an iron material such as iron, nickel, or cobalt. In addition to, or instead of, this, the susceptor 140 may include a semiconductor such as silicon carbide, carbon, or graphite.

[0121] Each induction heating element present within the aerosol-generating device may have any suitable shape. In the embodiment shown in Figure 1B, the induction heating elements 114, 124 define a receiving portion that surrounds the aerosol-generating article and heats the aerosol-generating article from the outside. In other embodiments (not shown), one or more induction heating elements may be substantially elongated and arranged to pierce the aerosol-generating article and heat the aerosol-generating article from the inside.

[0122] As shown in FIG. 1B, the first induction heating element 114 and the second induction heating element 124 may be provided together as an integral element 140. That is, in some embodiments, there is no physical distinction between the first heating element 114 and the second heating element 124. Rather, the different characteristics between the first heating unit 110 and the second heating unit 120 are determined by separate inductor coils 112, 122 surrounding each induction heating element 114, 124, and as a result, they can be controlled independently of each other. In other embodiments (not shown), physically different induction heating elements may be used.

[0123] The first inductor coil 112 and the second inductor coil 122 are made of a conductive material. In this example, the first inductor coil 112 and the second inductor coil 122 are made of a Litz wire / cable wound in a spiral so as to provide spiral inductor coils 112, 122. The Litz wire comprises a plurality of individual wires, and these wires are individually insulated and twisted together to form a single wire. The Litz wire is designed to reduce the skin effect losses of the conductor. In the exemplary induction heating assembly 100, the first inductor coil 124 and the second inductor coil 126 are made of a copper Litz wire having a circular cross-section. In other examples, the Litz wire can have a cross-section of other shapes, such as rectangular.

[0124] The first inductor coil 112 is configured to generate a first variable magnetic field for heating the first induction heating element 114, and the second inductor coil 122 is configured to generate a second variable magnetic field for heating the second portion of the susceptor 124. The first inductor coil 112 and the first induction heating element 114 together form the first induction heating unit 110. Similarly, the second inductor coil 122 and the second induction heating element 124 together form the second induction heating unit 120.

[0125] In this example, the first inductor coil 112 is adjacent to the second inductor coil 122 (i.e., the first inductor coil 112 and the second inductor coil 122 do not overlap) in a direction along the longitudinal axis of the device heating assembly 100. The susceptor structure 140 may comprise a single susceptor. The end 150 of the first inductor coil 112 and the end 150 of the second inductor coil 122 can be connected to a controller such as a PCB (not shown). In a preferred embodiment, the controller comprises a PID controller (proportional integral derivative controller).

[0126] The varying magnetic field generates eddy currents in the first induction heating element 114, thereby supplying an alternating current to the coil 112 and rapidly heating the first induction heating element 114 to its maximum operating temperature within a short time, for example within 20, 15, 12, 10, 5, or 2 seconds. Arranging the first induction heating unit 110 configured to rapidly reach the maximum operating temperature closer to the mouth-side end 102 of the heating assembly 100 than the second induction heating unit 120 can mean that an acceptable aerosol is supplied to the user as soon as possible after the start of the usage session.

[0127] It will be appreciated that in some examples, the first inductor coil 112 and the second inductor coil 122 may have at least one characteristic that is different from each other. For example, the first inductor coil 112 may have at least one characteristic that is different from the second inductor coil 122. More specifically, in one example, the first inductor coil 112 may have an inductance value that is different from that of the second inductor coil 122. In FIGS. 1A and 1B, the first inductor coil 112 and the second inductor coil 122 are coils of different lengths, and as a result, the first inductor coil 112 is wound around a smaller portion of the susceptor 140 than the second inductor coil 122. Thus, (assuming that the spacing between individual turns is substantially the same), the first inductor coil 112 may include a different number of turns than the second inductor coil 122. In yet another example, the first inductor coil 112 may be made of a material different from that of the second inductor coil 122. In some examples, the first inductor coil 112 and the second inductor coil 122 may be substantially identical.

[0128] In this example, the first inductor coil 112 and the second inductor coil 122 are wound in the same direction. However, in another embodiment, the inductor coil 112 and the inductor coil 122 may be wound in opposite directions. This can be useful when the inductor coils are operating while being different. For example, initially, the first inductor coil 112 may be operating to heat the first inductive heating element 114, and then the second inductor coil 122 may be operating to heat the second inductive heating element 124. Winding the coils in opposite directions helps reduce the current induced in the non-operating coil when used with a particular type of control circuit. In one example, the first inductor coil 112 may be a right-handed helix and the second inductor coil 122 may be a left-handed helix. In another example, the first inductor coil 112 may be a left-handed helix and the second inductor coil 122 may be a right-handed helix.

[0129] Coils 112 and 122 may have any suitable geometry. Although not desired to be restricted by theory, making the induction heating element smaller (e.g., reducing the pitch of the helix, reducing the number of turns of the helix, shortening the overall length of the helix) can increase the rate at which the induction heating element can reach its maximum operating temperature. In some embodiments, the first coil 112 may have a length of less than about 20 mm, less than 18 mm, less than 16 mm, or about 14 mm in the longitudinal direction of the heating assembly 100. Preferably, the first coil 112 can have a length shorter than that of the second coil 124 in the longitudinal direction of the heating assembly 100. With such a configuration, the aerosol-generating article can be heated asymmetrically along the length of the aerosol-generating article.

[0130] The susceptor 140 in this example is hollow and thus defines a receiving portion into which the aerosol-generating material is received. For example, the article 130 can be inserted into the susceptor 140. In this example, the susceptor 140 is tubular with a circular cross-section.

[0131] The induction heating element 114 and the induction heating element 124 are arranged to surround the smoking article 130 and heat the smoking article 130 from the outside. The aerosol-generating device is configured such that when the smoking article 130 is received within the susceptor 140, the outer surface of the article 130 abuts against the inner surface of the susceptor 140. This ensures that the heating is most efficient. The article 130 in this example comprises an aerosol-generating material. The aerosol-generating material is disposed within the susceptor 140. The article 130 may also comprise other components such as a filter, packaging material, and / or a cooling structure.

[0132] The heating assembly 100 is not limited to two heating units. In some examples, the heating assembly 100 may comprise three, four, five, six, or seven or more heating units. Each of these heating units may be controllable independently of the other heating units present within the heating assembly 100.

[0133] Referring to FIGS. 2A and 2B, a partially cut-away cross-sectional view and a perspective view of an example of the aerosol generating article 200 are shown. The aerosol generating article 200 shown in FIGS. 2A and 2B corresponds to the aerosol generating article 130 shown in FIG. 1.

[0134] The aerosol generating article 200 may be of any shape suitable for use with an aerosol generating device. The smoking article 130 may be in the form of a cartridge or cassette or rod that can be inserted into the device, or may be provided as part thereof. In the embodiments shown in FIGS. 1A, 1B and 2, the smoking article 130 is in the form of a substantially cylindrical rod and includes a body 202 of smoking material and a filter assembly 204 in the form of a rod. The filter assembly 204 includes three segments, namely a cooling segment 206, a filter segment 208, and a mouth-end segment 210. The article 200 has a first end 212, also known as the mouth-end or proximal end, and a second end 214, also known as the distal end. The body 202 of the aerosol generating material is disposed towards the distal end 214 of the article 200. In one example, the cooling segment 206 is disposed adjacent to the body 202 of the aerosol generating material between the body 202 of the aerosol generating material and the filter segment 208, such that the cooling segment 206 is in abutting relation with the aerosol generating material 202 and the filter segment 208. In other examples, there may be a gap between the body 202 of the aerosol generating material and the cooling segment 206, and between the body 202 of the aerosol generating material and the filter segment 208. The filter segment 208 is disposed between the cooling segment 206 and the mouth-end segment 210. The mouth-end segment 210 is disposed towards the proximal end 212 of the article 200 and is adjacent to the filter segment 208. In one example, the filter segment 208 is in abutting relation with the mouth-end segment 210. In one embodiment, the total length of the filter assembly 204 is from 37 mm to 45 mm, and more preferably 41 mm.

[0135] In use, portions 202a and 202b of the body 202 of the aerosol-generating material can respectively correspond to the first induction heating element 114 and the second induction heating element 124 of the portion 100 shown in FIG. 1B.

[0136] The body of the smoking article can have a plurality of portions 202a, 202b corresponding to a plurality of induction heating elements present within the aerosol-generating device. For example, the aerosol-generating article 200 can have a first portion 202a corresponding to the first induction heating element 114 and a second portion 202b corresponding to the second induction heating element 124. These portions 202a, 202b can exhibit different temperature profiles from each other during a use session, and the temperature profiles of portions 202a, 202b can result from the temperature profiles of the first induction heating element 114 and the second induction heating element 124 respectively.

[0137] When there are a plurality of portions 202a, 202b of the body 202 of the aerosol-generating material, any number of the substrate portions 202a, 202b can have substantially the same composition. In a particular example, all of the substrate portions 202a, 202b have substantially the same composition. In one embodiment, the body 202 of the aerosol-generating material is a single continuum, not physically separated between the first portion 202a and the second portion 202b, and the first portion and the second portion have substantially the same composition.

[0138] In one embodiment, the body 202 of the aerosol-generating material includes tobacco. However, in each of the other embodiments, the body 202 of the smoking article can consist of only tobacco, can consist substantially entirely of tobacco, can include tobacco and aerosol-generating materials other than tobacco, can include aerosol-generating materials other than tobacco, or can be without tobacco. The aerosol-generating material can include an aerosol-forming agent such as glycerol.

[0139] In certain embodiments, the aerosol-generating material can include one or more tobacco components, filler components, binders, and aerosol-forming agents.

[0140] The filler component may be any suitable inorganic filler material. Suitable inorganic filler materials include, but are not limited to, suitable inorganic adsorbents such as calcium carbonate (i.e., chalk), perlite, vermiculite, diatomaceous earth, colloidal silica, magnesium oxide, magnesium sulfate, magnesium carbonate, and molecular sieves. Calcium carbonate is particularly suitable. In some cases, the filler includes organic materials such as wood pulp, cellulose, and cellulose derivatives.

[0141] The binder may be any suitable binder. In some embodiments, the binder includes one or more of alginic acid, cellulose or modified cellulose, polysaccharides, starch or modified starch, and natural gums.

[0142] Suitable binders include, but are not limited to, alginates containing any suitable cation such as sodium alginate, calcium alginate, and potassium alginate, cellulose or modified cellulose such as hydroxypropyl cellulose and carboxymethyl cellulose, polysaccharides such as starch or modified starch, pectin salts containing any suitable cation such as sodium, potassium, calcium, or magnesium pectinate, xanthan gum, guar gum, and any other suitable natural gum.

[0143] The binder may be included in the aerosol-forming material in any suitable amount and concentration.

[0144] An "aerosol-forming agent" is an agent that promotes the formation of an aerosol. The aerosol-forming agent can promote the formation of an aerosol by promoting initial vaporization and / or condensation of a gas into a solid and / or liquid aerosol that can be inhaled. In some embodiments, the aerosol-forming agent can improve the delivery of flavor from a smoking article. Generally, any suitable one or more aerosol - generating agents may be included within the aerosol - generating material. Suitable aerosol - generating agents include, but are not limited to, polyols such as sorbitol, glycerol, and glycols such as propylene glycol or triethylene glycol, non - polyols such as monohydric alcohols, high - boiling hydrocarbons, acids such as lactic acid, glycerol derivatives, diacetin, triacetin, triethylene glycol diacetate, triethyl citrate, or esters such as myristic acid including ethyl myristate and isopropyl myristate, and aliphatic carboxylic acid esters such as methyl stearate, dimethyl dodecanedioate, and dimethyl tetradecanedioate.

[0145] In certain embodiments, the aerosol - generating material comprises a tobacco component in an amount of 60 - 90 wt% of the tobacco composition, a filler component in an amount of 0 - 20 wt% of the tobacco composition, and an aerosol - generating agent in an amount of 10 - 20 wt% of the tobacco composition. The tobacco component may include reconstituted tobacco in an amount of 70 - 100 wt% of the tobacco component.

[0146] In one example, the length of the body 202 of the aerosol - generating material is 34 mm to 50 mm, more preferably the length of the body 202 of the aerosol - generating material is 38 mm to 46 mm, and even more preferably the length of the body 202 of the aerosol - generating material is 42 mm.

[0147] In one example, the overall length of the article 200 is 71 mm to 95 mm, more preferably the overall length of the article 200 is 79 mm to 87 mm, and even more preferably the overall length of the article 200 is 83 mm.

[0148] The axial end of the body 202 of the aerosol - generating material can be seen at the distal end 214 of the article 200. However, in other embodiments, the distal end 214 of the article 200 may comprise an end member (not shown) that covers the axial end of the body 202 of the aerosol - generating material.

[0149] The body 202 of the aerosol generating material is joined to the filter assembly 204 by an annular chip paper (not shown), and the chip paper is substantially disposed around the filter assembly 204 to surround the filter assembly 204 and partially extends along the length of the body 202 of the aerosol generating material. In one example, the chip paper is made from a standard chip base paper of 58 GSM. In one example, the length of the chip paper is 42 mm to 50 mm, and a length of 46 mm is more preferred.

[0150] In one example, the cooling segment 206 is an annular tube that is disposed around and defines a void within the cooling segment. The void provides a chamber for the heated and volatilized components generated from the body 202 of the aerosol generating material to flow through. The cooling segment 206 is hollow to provide a chamber for storing the aerosol, but still has sufficient rigidity to withstand the axial compressive forces and bending moments that may occur during manufacturing and when the article 200 is used while inserted into the device 100. In one example, the wall thickness of the cooling segment 206 is about 0.29 mm.

[0151] The cooling segment 206 provides a physical spacing between the aerosol - forming material 202 and the filter segment 208. This physical spacing provided by the cooling segment 206 creates a thermal gradient across the length of the cooling segment 206. In one example, the cooling segment 206 is configured to provide a temperature difference of at least 40 °C between the heated and volatilized components entering the first end of the cooling segment 206 and the heated and volatilized components exiting the second end of the cooling segment 206. In one example, the cooling segment 206 is configured to provide a temperature difference of at least 60 °C between the heated and volatilized components entering the first end of the cooling segment 206 and the heated and volatilized components exiting the second end of the cooling segment 206. When heated by the heating assembly 100 of the device aerosol - generating device, this temperature difference created across the length of the cooling element 206 protects the temperature - sensitive filter segment 208 from the high temperature of the aerosol - forming material 202. If there is no physical spacing provided between the filter segment 208 and the body 202 of the aerosol - forming material and the heating elements 114, 124 of the heating assembly 100, the temperature - sensitive filter segment 208 may be damaged during use and thus may not effectively perform the required functions.

[0152] In one example, the length of the cooling segment 206 is at least 15 mm. In one example, the length of the cooling segment 206 is between 20 mm and 30 mm, more particularly between 23 mm and 27 mm, more particularly between 25 mm and 27 mm, more particularly 25 mm.

[0153] The cooling segment 206 is made of paper, which means that when adjacent to the heater assembly 100 of the aerosol generating device during use, it is composed of a material that does not generate problematic compounds, such as toxic compounds. In one example, the cooling segment 206 is manufactured from a spirally wound paper tube, which has a hollow internal chamber but still maintains mechanical rigidity. The spirally wound paper tube can meet the strict dimensional accuracy requirements of the high-speed manufacturing process with respect to the tube length, outer diameter, roundness, and straightness.

[0154] In another example, the cooling segment 206 is a recess made from stiff plug wrap paper or tipping paper. The stiff plug wrap paper or tipping paper is manufactured to have sufficient rigidity to withstand the axial compressive forces and bending moments that may occur during manufacturing and when used while the article 200 is inserted into the device 100.

[0155] For each of the examples of the cooling segment 206, the dimensional accuracy of the cooling segment is sufficient to meet the dimensional accuracy requirements of the high-speed manufacturing process.

[0156] The filter segment 208 may be formed from any filter material sufficient to remove one or more volatile compounds from the heated and volatilized components from the smoking material. In one example, the filter segment 208 is made from a monoacetate material such as cellulose acetate. The filter segment 208 cools the heated and volatilized components and reduces irritation therefrom without reducing the amount of the heated and volatilized components to an unsatisfactory level for the user.

[0157] The pressure drop between the two ends of the filter segment 208, and thus the draw resistance of the article 200, is controlled by the density of the cellulose acetate tow material of the filter segment 208. Therefore, the selection of the material of the filter segment 208 is important for controlling the draw resistance of the article 200. In addition, the filter segment 208 performs a filtering function in the article 200.

[0158] In one example, the filter segment 208 is made of 8Y15 grade filter tow material, which exerts a filtering effect on the heated and volatilized material, and on the other hand, also reduces the size of the condensed aerosol droplets generated from the heated and volatilized material, so that the irritation and the impact on the throat of the heated and volatilized material are reduced to a satisfactory level.

[0159] The presence of the filter segment 208 provides a heat insulation effect by further cooling the heated and volatilized components exiting the cooling segment 206. This further cooling effect lowers the temperature of the surface of the filter segment 208 that the user's lips contact.

[0160] One or more fragrances may be added to the filter segment 208 by directly injecting the scented liquid into the filter segment 208, or by embedding or disposing one or more scented fragile capsules or other fragrance carriers within the cellulose acetate tow of the filter segment 208.

[0161] In one example, the length of the filter segment 208 is 6 mm to 10 mm, and 8 mm is more preferred.

[0162] The mouth-side end segment 210 is an annular tube, which is disposed around the void within the mouth-side end segment 210 and defines the void within the mouth-side end segment 210. The void provides a chamber for the heated and volatilized components flowing from the filter segment 208. The mouth-side end segment 210 is hollow to provide a chamber for storing the aerosol, but still has sufficient rigidity to withstand the axial compressive forces and bending moments that may occur during manufacturing and when the article is used while inserted into the device 100. In one example, the wall thickness of the mouth-side end segment 210 is about 0.29 mm.

[0163] In one example, the length of the oral-side end segment 210 is 6 mm to 10 mm, and 8 mm is more preferable. In one example, the thickness of the oral-side end segment is 0.29 mm.

[0164] The oral-side end segment 210 may be manufactured from a spirally wound paper tube, which has a hollow internal chamber but still maintains the final mechanical rigidity. The spirally wound paper tube can meet the strict dimensional accuracy requirements of the high-speed manufacturing process with respect to the tube length, outer diameter, roundness, and straightness.

[0165] The oral-side end segment 210 provides a function of preventing any liquid condensate accumulating at the outlet of the filter segment 208 from coming into direct contact with the user.

[0166] In one example, the oral-side end segment 210 and the cooling segment 206 may be formed from a single tube, and it should be understood that the filter segment 208 is disposed therein to separate the oral-side end segment 210 and the cooling segment 206.

[0167] The article 200 is provided with a ventilation region 216 so as to allow air to flow from the outside of the article 200 into the inside of the article 200. In one example, the ventilation region 216 takes the form of one or more ventilation holes 216 formed through the outer layer of the article 200. The ventilation holes may be disposed in the cooling segment 206 to assist in cooling the article 200. In one example, the ventilation region 216 preferably comprises one or more rows of holes, and each row of holes is disposed over the entire circumference of the article 200 in a cross-section substantially perpendicular to the longitudinal axis of the article 200.

[0168] In one example, there are 1 to 4 rows of ventilation holes for ventilating the article 200. Each row of ventilation holes may have 12 to 36 ventilation holes 216. The diameter of the ventilation holes 216 may be, for example, 100 to 500 μm. In one example, the axial interval between rows of the ventilation holes 216 is 0.25 mm to 0.75 mm, and 0.5 mm is more preferable for the axial interval between rows of the ventilation holes 216.

[0169] In one example, the vent holes 216 are holes of uniform size. In another example, the vent holes 216 are of different sizes. The vent holes can be made using one or more of any suitable techniques, such as laser techniques, mechanical perforation of the cooling segment 206, or pre-perforation before forming the cooling segment 206 on the article 200. The vent holes 216 are arranged to effectively cool the article 200.

[0170] In one example, the row of vent holes 216 is arranged at least 11 mm from the proximal end 212 of the article, and more preferably, the vent holes are arranged 17 mm to 20 mm from the proximal end 212 of the article 200. The position of the vent holes 216 is arranged so that the user does not block the vent holes 216 during use of the article 200.

[0171] As can be seen from FIG. 1, by providing a row of vent holes 17 mm to 20 mm from the proximal end 212 of the article 200, it is advantageous that when the article 200 is fully inserted into the device 100, the vent holes 216 can be arranged outside the device 100. By arranging the vent holes outside the device, unheated air can enter the article 200 through the vent holes from outside the device 100 to assist in cooling the article 200.

[0172] The length of the cooling segment 206 is such that when the article 200 is fully inserted into the device 100, the cooling segment 206 is partially inserted into the device 100. This length of the cooling segment 206 provides a first function of providing a physical gap between the heater assembly of the device 100 and the heat-sensitive filter assembly 208, and a second function of allowing the vent holes 216 to be located within the cooling segment but also outside the device 100 when the article 200 is fully inserted into the device 100. As can be seen from FIG. 1, most of the cooling element 206 is located within the device 100. However, a portion of the cooling element 206 extends outside the device 100. The vent holes 216 are arranged in this portion of the cooling element 206 that extends outside the device 100.

[0173] Figure 3 shows the programmed temperature profile 300 of the heating unit of the aerosol generating device during an exemplary use session 302. The temperature profile 300 preferably refers to a stepped heating profile of any heating unit in any operating mode of the heating assembly.

[0174] The programmed heating profile 300 includes a first temperature 302, which is a first temperature programmed such that the heating unit reaches it at a first time point 304 during a given use session. It is convenient that the first time point 304 can be determined by the number of seconds elapsed since the start of the use session, i.e., the time when power was first supplied to at least one heating unit present within the heating assembly.

[0175] The programmed heating profile 300 includes a second temperature 306 that is different from the first temperature 302. The heating unit is programmed to reach the second temperature 306 at a second time point 308 during a given use session. The second time point 308 comes after the first time point 304 in time. From the first time point 304 to the second time point 308, the heating unit is programmed to have substantially the same temperature, and the heating unit is maintained at the first temperature 302. In one embodiment, the second temperature 306 is higher than the first temperature 302.

[0176] The programmed heating profile 300 includes a third temperature 310 that is different from the second temperature. The heating unit is programmed to reach the third temperature 310 at a third time point 312 during a given use session. The third time point 312 comes after the second time point 308, and thus after the first time point 302 in time. In one embodiment, the third temperature 310 is higher than the second temperature 306.

[0177] The programmed heating profile 300 includes a final point 314 at which the supply of energy to the heating unit is stopped for the remainder of the use session. The final point 314 may coincide with the end of the use session.

Example

[0178] Reference Example Figure 4 shows the programmed heating profiles of the first heating unit 110 (solid line) and the second heating unit 120 (dashed line) of the heating assembly 100 as shown in FIG. 1, operating in the first operating mode.

[0179] The heating assembly 100 is programmed such that the first heating unit 110 reaches its maximum operating temperature of 235° C. as quickly as possible. The heating assembly 100 is programmed such that the first heating unit 110 remains at a temperature of 235° C. for the first 190 seconds of the use session and then decreases to a temperature of 220° C. for the remainder of the use session.

[0180] The heating assembly 100 is programmed such that the second heating unit 120 reaches a first temperature of 160° C. at approximately 87 seconds after the start of the use session. The heating assembly 100 is programmed such that the second heating unit 120 subsequently rises to a maximum heating temperature of 220° C. at approximately 175 seconds after the start of the use session and remains at that temperature until the end of the use session at 265 seconds after the start of the use session.

[0181] Using the device configured as described above, a standard condensation experiment was performed to determine the amount of condensate accumulated in the device.

[0182] Standard Condensation Experiment The mass of the device was measured before the use session was conducted. Then, the use session was conducted 12 times without removing the condensate from the device. For each use session, a new tobacco rod was supplied to the device.

[0183] The mass of the device was measured after 4, 8, and 12 usage sessions. At each stage, the mass was measured immediately after the end of the usage session and also after a break of approximately 25 minutes from the end of the usage session.

[0184] After 12 sessions, the mass of the device was measured. The mass of the device before the experiment was subtracted from the mass of the device after the experiment to obtain the mass of the condensate accumulated in the device during 12 usage sessions. The experiment was repeated twice.

[0185] The results of the standard condensation experiment of Reference Example 1 are shown in Table 1.

Table 1

[0186] The average of the total mass of the condensate remaining in the device after 12 usage sessions was approximately 61 mg.

[0187] Example FIG. 5 shows the programmed heating profiles of the first heating unit 110 (solid line) and the second heating unit 120 (dashed line) of the heating assembly 100 as shown in FIG. 1, which is operated in another first operating mode.

[0188] The heating assembly 100 was programmed such that the first heating unit 110 reaches the first operating temperature of 235° C. as quickly as possible. The heating assembly 100 was programmed such that the first heating unit 110 remains at a temperature of 235° C. for the first 120 seconds of the usage session and then rises to a maximum operating temperature of 245° C. until 225 seconds have elapsed from the start of the usage session and then drops to a temperature of 220° C. for the remainder of the usage session.

[0189] The heating assembly 100 is such that the second heating unit 120 a) reaches a first temperature of 100° C. at approximately 100 seconds after the start of the usage session, b) It rises to a second temperature of 140 °C approximately 120 seconds after the start of the usage session, and then, c) It rises to a third temperature of 160 °C approximately 140 seconds after the start of the usage session, and then, d) It rises to a fourth temperature of 200 °C approximately 180 seconds after the start of the usage session, and then, e) It rises to a fifth maximum operating temperature of 220 °C approximately 225 seconds after the start of the usage session, and is programmed to stay at that temperature until the end of the usage session 265 seconds after the start of the usage session.

[0190] The device configured as described above was analyzed according to the standard condensation experiment described in the reference example. The results of this experiment are shown in Table 2.

Table 2

[0191] The average of the total mass of the condensate remaining in the device after 12 usage sessions was approximately 50 mg. This represents a reduction in condensate of more than 18% compared to the reference example.

[0192] The above-described embodiments are to be understood as examples for explaining the present invention. Further embodiments of the present invention are also envisioned. It should be understood that any feature described in connection with any one embodiment may be used alone or in combination with other features described, and may also be used in combination with one or more features of any other embodiment or any combination of any other embodiments. Furthermore, equivalents and modifications not described above may be used without departing from the scope of the present invention defined in the appended claims.

Claims

1. An aerosol generating device for generating an aerosol from an aerosol generating material, comprising one or more heating units configured to heat the aerosol generating material during use without combustion, and a controller for controlling the one or more heating units wherein the heating assembly includes, during a usage session, the controller is programmed such that at least one of the one or more heating units is sequentially heated to at least three different temperatures and held at each of the at least three different temperatures for at least 0.5 seconds, the at least three different temperatures include a first temperature at which the heating unit is heated and held for at least 0.5 seconds, and the first temperature is lower than 120°C, an aerosol generating device.

2. The aerosol generating device according to claim 1, wherein the at least three different temperatures include the first temperature, a second temperature reached by the heating unit after being held at the first temperature, and a third temperature reached by the heating unit after being held at the second temperature, and the second temperature is higher than the first temperature.

3. The aerosol generating device according to claim 2, wherein the second temperature is less than 60°C higher than the first temperature.

4. The aerosol generating device according to claim 2 or 3, wherein the third temperature is higher than the second temperature.

5. The aerosol generating device according to claim 4, wherein the third temperature is less than 60°C higher than the second temperature.

6. An aerosol generating device for generating an aerosol from an aerosol generating material, comprising one or more heating units configured to heat the aerosol generating material during use without combustion, and a controller for controlling the one or more heating units wherein the heating assembly includes, during a usage session, the controller is programmed such that at least one of the one or more heating units is sequentially heated to at least three different temperatures and held at each of the at least three different temperatures for at least 0.5 seconds, The at least three different temperatures include a first temperature, a second temperature that the heating unit reaches after being maintained at the first temperature, and a third temperature that the heating unit reaches after being maintained at the second temperature, the second temperature being higher than the first temperature, the first temperature being from 40°C to 130°C, an aerosol generation device.

7. The aerosol generation device according to any one of claims 1 to 6, wherein, whenever at least one of the one or more heating units is heated from a previous temperature to a new temperature, the new temperature is higher than the previous temperature until the heating unit reaches its maximum operating temperature.

8. The aerosol generation device according to any one of claims 1 to 7, wherein the one or more heating units include a first heating unit and a second heating unit.

9. The aerosol generation device according to claim 8, wherein the heating assembly has a mouth-side end and a distal end, the first heating unit is disposed closer to the mouth-side end than the second heating unit, and at least one of the one or more heating units includes the second heating unit.

10. An aerosol generation device for generating an aerosol from an aerosol generation material, one or more heating units configured to heat the aerosol generation material during use without combusting it, a controller for controlling the one or more heating units and including a heating assembly, during a use session, at least one of the one or more heating units is sequentially heated to at least three different temperatures and the controller is programmed to be held at each of the at least three different temperatures for at least 0.5 seconds, the one or more heating units including a first heating unit and a second heating unit, the heating assembly having a mouth-side end and a distal end, the first heating unit being disposed closer to the mouth-side end than the second heating unit, and at least one of the one or more heating units including the second heating unit, the heating assembly being configured such that the second heating unit is heated to a temperature of 80°C or higher, but not before 20 seconds have elapsed since the start of the use session, an aerosol generation device.

11. The aerosol generating device according to any one of claims 8 to 10, wherein the heating assembly is configured such that the first heating unit reaches a temperature of 200°C to 300°C within 20 seconds from the start of the usage session.

12. The aerosol generating device according to any one of claims 1 to 11, wherein each heating unit of the heating assembly comprises a coil.

13. The aerosol generating device according to claim 12, wherein each heating unit of the heating assembly is an induction heating unit comprising a coil configured to be an inductor element for supplying a varying magnetic field to a susceptor heating element.

14. The aerosol generating device according to any one of claims 1 to 12, wherein each heating unit of the heating assembly is a resistive heating unit.

15. The aerosol generating device according to any one of claims 1 to 14, wherein the aerosol generating device is a tobacco heating product.

16. An aerosol generating system comprising the aerosol generating device according to any one of claims 1 to 15 in combination with an aerosol generating article comprising an aerosol generating material.

17. A method of generating an aerosol from an aerosol generating material using the aerosol generating device according to any one of claims 1 to 15, the method comprising: sequentially reaching at least three different temperatures; holding at each of the at least three different temperatures for at least 0.5 seconds; and instructing at least one of one or more heating units of the device heating unit to do so.

Images