Aerosol generation system and aerosol generator having resistance heating and induction heating arrangements

Abstract

An aerosol generator is provided, comprising a chamber for receiving at least a portion of an aerosol-generating article. The aerosol generator includes an inductor element positioned adjacent to or within the chamber, a resistive heating element positioned adjacent to or within the chamber, at least one power supply for providing power to the inductor element and the resistive heating element, and a control circuit configured to control the power supply from the at least one power supply to the inductor element and the resistive heating element. The control circuit is configured to provide a first current to the inductor element so that the inductor element generates an alternating magnetic field within the chamber. The control circuit is further configured to provide a second current to the resistive heating element to heat the chamber.

Description

Technical Field

[0001] The present disclosure relates to an aerosol generation system and an aerosol generator for generating an aerosol from an aerosol-forming substrate.

Background Art

[0002] It is known to generate an aerosol from an aerosol-forming substrate of an aerosol-generating article without burning or combusting the substrate by applying heat to the substrate. The aerosol-generating article may be cylindrical such as a cigarette, and the aerosol-forming substrate may contain tobacco material. It is known to apply heat to such an aerosol-generating article and heat the aerosol-forming substrate of the article using a heat source located outside the aerosol-generating article.

[0003] However, an external heat source tends to heat the aerosol-forming substrate non-uniformly. The aerosol-forming substrate closest to the heat source is at the center of the aerosol-generating article and is heated more than the aerosol-forming substrate farther from the heat source.

[0004] It is also known to use a heat source located inside the aerosol-forming substrate to heat the aerosol-forming substrate of such an article. In some aerosol generation systems, the internal heat source is inductively heated using an induction coil located outside the aerosol-generating article and a susceptor material located within the central region of the aerosol-generating article. By heating the aerosol-forming substrate internally, it is avoided that heat has to cross through the wrapper and reach the aerosol-forming substrate. However, even when the aerosol-forming substrate is heated internally, the aerosol-forming substrate is heated in a non-uniform manner, and the heating of the substrate is greatest at or closest to the internal heat source and decreases as it enters the substrate away from the internal heat source.

[0005] Uneven heating of an aerosol-forming substrate can mean that not all available volatile materials are released from the aerosol-forming substrate. This is because increasing the level of heat applied to the substrate to completely extract the volatile materials from the aerosol-forming substrate, whether using external or internal heating, can lead to unintended and undesirable combustion of the substrate near the heat source, resulting in the generation of undesirable compounds and flavors.

[0006] Therefore, there is a need to provide an aerosol generation system and aerosol generation device that efficiently releases usable volatile materials from an aerosol-forming substrate by uniformly heating the aerosol-forming substrate. [Overview of the project]

[0007] The present disclosure provides an aerosol generator. The aerosol generator may include a chamber for receiving at least a portion of an aerosol generating article. The aerosol generator may include an inductor element located adjacent to or within the chamber. The aerosol generator may include a resistive heating element located adjacent to or within the chamber. The aerosol generator may include at least one power supply for supplying power to the inductor element and to the resistive heating element. The aerosol generator may include a control circuit configured to control the power supply from at least one power supply to the inductor element. The aerosol generator may include a control circuit configured to control the power supply from at least one power supply to the resistive heating element. The control circuit may be configured to supply a first current to the inductor element. The control circuit may be configured to supply a first current to the inductor element so that the inductor element generates an alternating magnetic field within the chamber. The control circuit may be configured to supply a second current to the resistive heating element. The control circuit may be configured to supply a second current to the resistive heating element to heat the chamber.

[0008] According to a first aspect of this disclosure, an aerosol generator is provided, which is an aerosol generator

[0009] A chamber for receiving at least a portion of an aerosol-generating article,

[0010] An inductor element positioned adjacent to or within the chamber,

[0011] A resistance heating element positioned adjacent to or inside the chamber,

[0012] At least one power supply for providing power to an inductor element and a resistive heating element,

[0013] A control circuit configured to control the power supply from at least one power source to an inductor element and to a resistive heating element,

[0014] The control circuit is configured to supply a first current to the inductor element so that the inductor element generates an alternating magnetic field within the chamber.

[0015] The control circuit is configured to supply a second current to the resistive heating element in order to heat the chamber.

[0016] Advantageously, providing induction heating and resistance heating, respectively, by using separate inductor elements and resistance heating elements means that the characteristics, shape, and materials of the inductor elements and resistance heating elements can be individually adapted and optimized to more efficiently heat the aerosol-forming substrate. For example, the inductor element may be optimized for induction heating, and the resistance heating element may be optimized for resistance heating.

[0017] The first current may be an alternating current. The alternating current may have a first frequency. The control circuit may be configured so that a second current is not supplied to the inductor element. The control circuit may be configured so that a direct current is not supplied to the inductor element. The control circuit may be configured so that only the first current is supplied to the inductor element. Advantageously, this may result in minimal resistive heating of the inductor element, thereby reducing the risk of overheating or burning of the peripheral portion of the aerosol-forming substrate.

[0018] When the first current is supplied, the inductor element may generate an alternating magnetic field within the chamber, thereby inductively heating one or more susceptors within the aerosol-generating article when the article is received into the chamber. Therefore, advantageously, the aerosol-forming substrate within the aerosol-generating article can be efficiently heated from both the outside and the inside.

[0019] An aerosol-forming article may comprise one or more susceptors. Each of the susceptors may be in the form of at least one strip, or at least one rod, or at least one particle. Advantageously, the structure of the aerosol generator can be simplified because the aerosol generator does not need to include susceptor elements. Each of the susceptors may be in the form of elongated particles. The elongated particles may be aligned along the long axis of the aerosol-forming article. The elongated particles may also be aligned along the long axis of the aerosol-forming substrate. Each of the susceptors may be in the form of one or more strips made of a susceptor material. An aerosol-forming article may comprise one or more strips of an aerosol-forming substrate laminated with one or more strips made of a susceptor material. For example, an aerosol-forming article may comprise one or more strips of tobacco material laminated with one or more strips made of a susceptor material.

[0020] The aerosol generator may comprise one or more susceptors. Each of the susceptors may be in the form of at least one blade or at least one pin. Advantageously, each of the susceptors may be reused with multiple aerosol-forming articles. Each of the susceptors may be configured to be inserted into the aerosol-generating substrate when the aerosol-generating article is received into the chamber. Advantageously, this may allow for a simpler and more sustainable configuration when using the aerosol-forming article.

[0021] The second current may be a direct current. The control circuit may be configured such that the first current is not supplied to the resistive heating element. The control circuit may be configured such that no alternating current is supplied to the resistive heating element. The control circuit may be configured so that only the second current is supplied to the resistive heating element. Advantageously, this may mean that the resistive heating element does not have a magnetic interaction with the inductor element.

[0022] The power supply may include a first DC power supply. Advantageously, a suitable DC power supply within a certain range may be suitable for use in an aerosol generator. The first DC power supply may be a battery. The control circuit may include a DC / AC converter connected to the first DC power supply. Advantageously, a single DC power supply can be used to power both the resistive heating element and the inductor element.

[0023] The DC / AC converter may include a Class E power amplifier comprising a first transistor switch and an LC load network.

[0024] The control circuit may be configured to supply a second current to the resistive heating element so that the resistive heating element is heated to at least 80°C. Advantageously, heating the resistive heating element to at least 80°C may ensure that the resistive heating element adequately heats the aerosol-forming substrate so that vapor can be generated. The control circuit may be configured to supply a second current to the resistive heating element so that the resistive heating element is heated not to exceed 210°C. Advantageously, heating the resistive heating element not to exceed 210°C may ensure that the resistive heating element does not burn or char the aerosol-forming substrate, thereby ensuring that an aerosol is not generated that produces undesirable compounds and gives the user a burnt taste.

[0025] The control circuit may be configured to supply a first current to the inductor element and a second current to the resistive heating element at different times.

[0026] For example, the control circuit may be configured to supply a first current to an inductor element, and then a second current to a resistive heating element. The control circuit may be configured to supply a first current to an inductor element over a first time period. The control circuit may be configured to supply a second current to a resistive heating element over a second time period following the first time period. Advantageously, the aerosol-forming substrate may be non-uniform, and different parts of the aerosol-forming substrate may be heated at different times by heating the aerosol-forming substrate by induction heating followed by resistance heating. Because the aerosol-forming substrate may be non-uniform, aerosols with aerosol properties may be generated at different times.

[0027] The control circuit may be configured to supply a second current to the resistive heating element, and then to supply a first current to the inductor element. The control circuit may be configured to supply a second current to the resistive heating element over a first time period. The control circuit may be configured to supply a first current to the inductor element over a second time period following the first time period. Advantageously, the aerosol-forming substrate may be non-uniform, and different parts of the aerosol-forming substrate may be heated at different times by heating the aerosol-forming substrate by resistive heating followed by induction heating. Because the aerosol-forming substrate may be non-uniform, aerosols with aerosol properties may be generated at different times.

[0028] The control circuit may be configured to detect when a user is inhaling smoke on the system. For example, the control circuit may be coupled to a pressure sensor, which is configured to detect a pressure drop when a user is inhaling smoke on the system. The control circuit may be configured to supply power to an inductor element or a resistive heating element, or to both an inductor element and a resistive heating element, when the pressure sensor detects a pressure drop when a user is inhaling smoke on the system. For example, the control circuit may be configured to initiate a first time period in response to a user inhaling smoke on the system.

[0029] The control circuit may include a user-activatable trigger. For example, the user-activatable trigger may be a button or a switch. The control circuit may be configured to start a first time period in response to the activation of the user-activatable trigger.

[0030] The control circuit is, The system has performed a predetermined number of smoke inhalations, or A predetermined amount of time has elapsed since the first smoke extraction on the system, or A user-activated trigger has been activated, or The system may be configured to terminate the first time period and begin the second time period in response to any one or more of the above-mentioned combinations.

[0031] The control circuit may be configured to provide a first current to the inductor element and a second current to the resistive heating element in an alternating sequence. Advantageously, alternating between induction heating and resistive heating may be beneficial to avoid overheating of any portion of the aerosol-forming substrate.

[0032] The control circuit may include a microcontroller. The control circuit may be configured to receive inductor feedback signals from an inductor element and to receive resistive heating feedback signals from a resistive heating element. For example, the microcontroller may be configured to receive inductor feedback signals from an inductor element and to receive resistive heating feedback signals from a resistive heating element.

[0033] An inductor feedback signal may comprise at least one of voltage, current, or conductance. For example, an inductor feedback signal may include both voltage and current. A resistive heating feedback signal may comprise at least one of voltage, current, or conductance. For example, a resistive heating feedback signal may include both voltage and current.

[0034] The control circuit may be configured to supply a first current to the inductor element based on an inductor feedback signal. The control circuit may be configured to supply a second current to the resistive heating element based on a resistive heating feedback signal. The inductor feedback signal may depend on the temperature of the susceptor. The resistive heating feedback signal may depend on the temperature of the resistive heating element.

[0035] The control circuit may be configured to adjust the first current supplied to the inductor element depending on the inductor feedback signal. The control circuit may be configured to determine the temperature of the inductor element depending on the inductor feedback signal. The control circuit may be configured to maintain the temperature of the susceptor element at the susceptor target temperature or to follow the susceptor target temperature profile by adjusting the first current supplied to the inductor element depending on the inductor feedback signal.

[0036] The control circuit may be configured to adjust a second current supplied to the resistive heating element depending on the resistive heating feedback signal. The control circuit may be configured to determine the temperature of the resistive heating element depending on the resistive heating feedback signal. By adjusting the second current supplied to the resistive heating element depending on the resistive heating feedback signal, the control circuit may be configured to maintain the temperature of the resistive heating element at a resistive heating target temperature or to make it follow a resistive heating target temperature profile.

[0037] When an alternating magnetic field is generated by supplying an alternating current to an inductor coil, the alternating magnetic field may induce an alternating current in the resistive heating element. Therefore, when a second current is supplied to the resistive heating element and the first current is supplied to the inductor element at the same time, the alternating current induced in the resistive heating element may affect the resistive heating feedback signal provided to the control circuit. For example, the alternating current induced in the resistive heating element may modify the resistive heating feedback signal provided to the control circuit. This may affect the control circuit's ability to accurately determine the temperature of the resistive heating element, and therefore its ability to maintain the temperature of the resistive heating element at or follow the resistive heating target temperature profile.

[0038] Therefore, the control circuit may be configured to block the supply of a second current to the resistive heating element when a first current is supplied to the inductor element. For example, the control circuit may be configured to block the supply of a direct current to the resistive heating element when an alternating current is supplied to the inductor element. Advantageously, if the control circuit is configured to block the supply of a second current to the resistive heating element when a first current is supplied to the inductor element, the induced alternating current does not affect the resistive heating feedback signal. Thus, the control circuit can determine the temperature of the resistive heating element more accurately.

[0039] Similarly, the control circuit may be configured to prevent the supply of the first current to the inductor element when the second current is being supplied to the resistive heating element. The control circuit may also be configured to prevent the simultaneous supply of the first current to the inductor element and the second current to the resistive heating element.

[0040] The control circuit may be configured to supply a first current to the inductor element during the ON period and to prevent the supply of the first current to the inductor element during the OFF period. The control circuit may be configured to alternate between ON and OFF periods.

[0041] Specifically, the microcontroller may be configured to supply a switching voltage to a DC / AC converter in order to control a first current supplied to an inductor element. In particular, the microcontroller may be configured to supply a switching voltage to the field-effect transistor of the DC / AC converter in order to control a first current supplied to an inductor element. The switching voltage may have a rectangular profile. The switching voltage may include alternating on periods in which the first current is supplied to the inductor element and off periods in which the supply of the first current to the inductor element is prevented.

[0042] The temperature of the susceptor element may be controlled by adjusting the length of the on-period. For example, the control circuit may be configured to adjust the length of the on-period to maintain the temperature of the susceptor element at the susceptor target temperature or to follow the susceptor target temperature profile.

[0043] The control circuit may be configured to supply a first current to the inductor element in one or more pulses during each ON period. The pulses may consist of multiple separate pulses. The control circuit may be configured to block the supply of the first current to the inductor element when there are no pulses.

[0044] The control circuit may be configured to control the temperature of the susceptor element by adjusting the pulses during each on-period. For example, the control circuit may be configured to control the temperature of the susceptor element by using pulse width modulation. The control circuit may be configured to control the temperature of the susceptor element by adjusting one or more of the duration of each pulse, the number of each pulse, or the time gap between adjacent pulses during each on-period. For example, the control circuit may be configured to maintain the temperature of the susceptor element at the susceptor target temperature or to follow the susceptor target temperature profile by adjusting the pulses during each on-period.

[0045] The pulse may occupy a proportion of each on-period. For example, the pulse may occupy 100% of each on-period so that a primary current is supplied to the inductor element for the entire duration of each on-period. Alternatively, the pulse may occupy 50% of each on-period so that a primary current is supplied to the inductor element for half the duration of each on-period. The control circuit may be configured to control the temperature of the susceptor element by adjusting the proportion of each on-period occupied by the pulse. For example, the control circuit may be configured to maintain the temperature of the susceptor element at a susceptor target temperature or to follow a susceptor target temperature profile by adjusting the proportion of each on-period occupied by the pulse.

[0046] The ON period may be 3000 milliseconds to 1 millisecond. The ON period may be 500 milliseconds to 1 millisecond. Preferably, the ON period is 100 milliseconds to 5 milliseconds. More preferably, the ON period is 50 milliseconds to 10 milliseconds. Even more preferably, the ON period is about 20 milliseconds.

[0047] The off-period may have a length of 3000 milliseconds to 1 millisecond. The off-period may have a length of 500 milliseconds to 1 millisecond. Preferably, the off-period has a length of 200 milliseconds to 10 milliseconds. More preferably, the off-period has a length of 100 milliseconds to 50 milliseconds. Even more preferably, the off-period has a length of approximately 70 milliseconds.

[0048] The control circuit may be configured to supply a second current to the resistive heating element during the off period. In particular, the control circuit may be configured to supply a second current to the resistive heating element only during the off period.

[0049] The temperature of the resistive heating element may be controlled by adjusting the length of the off period. For example, the control circuit may be configured to maintain the temperature of the resistive heating element at a resistive heating target temperature or to follow a resistive heating target temperature profile by adjusting the length of the off period.

[0050] The control circuit may be configured to supply a second current to the resistive heating element in one or more pulses during each off period. The pulses may consist of multiple separate pulses. The control circuit may be configured to block the supply of the second current to the resistive heating element when there are no pulses.

[0051] The control circuit may be configured to control the temperature of the resistive heating element by adjusting the pulses during each off period. For example, the control circuit may be configured to control the temperature of the resistive heating element by using pulse width modulation. The control circuit may be configured to control the temperature of the resistive heating element by adjusting one or more of the duration of each pulse, the number of each pulse, or the time gap between adjacent pulses during each off period. For example, the control circuit may be configured to maintain the temperature of the resistive heating element at a resistive heating target temperature or to follow a resistive heating target temperature profile by adjusting the pulses during each off period.

[0052] The pulse may occupy a proportion of each off period. For example, the pulse may occupy 100% of each off period so that a second current is supplied to the resistive heating element for the entire duration of each off period. Alternatively, the pulse may occupy 50% of each off period so that a second current is supplied to the resistive heating element for half the duration of each off period. The control circuit may be configured to control the temperature of the resistive heating element by adjusting the proportion of each off period occupied by the pulse. For example, the control circuit may be configured to maintain the temperature of the resistive heating element at a resistive heating target temperature or to follow a resistive heating target temperature profile by adjusting the proportion of each off period occupied by the pulse.

[0053] The control circuit may be configured to supply a second current to the resistive heating element over reduced time periods. Each reduced time period may be shorter than each off period. The control circuit may be configured to control the temperature of the resistive heating element by adjusting the length of the reduced time periods. Advantageously, by supplying a second current to the resistive heating element over reduced time periods shorter than the off periods during off periods, the control circuit can avoid any overlap between the first current supplied to the inductor element and the second current supplied to the resistive heating element. Advantageously, including a time gap between the reduced time periods and the period during which the first current is supplied to the inductor element, because the alternating current induced in the resistive heating element cannot instantaneously drop to zero when the first current supplied to the inductor element is stopped, can reduce noise in the resistive heating feedback signal caused by any alternating current induced in the resistive heating element. Also advantageously, the temperature of the resistive heating element may be controlled by adjusting the length of the reduced time periods. For example, the control circuit may be configured to maintain the temperature of the resistive heating element at the resistive heating target temperature or to follow the resistive heating target temperature profile by adjusting the length of the reduced time period. The temperature of the resistive heating element may be controlled by adjusting the length of the time gap between the reduced time period and the on period. For example, the control circuit may be configured to maintain the temperature of the resistive heating element at the resistive heating target temperature or to follow the resistive heating target temperature profile by adjusting the length of the time gap between the reduced time period and the on period. This allows the control circuit to maintain the temperature of the resistive heating element at the resistive heating target temperature or to follow the resistive heating target temperature profile using pulse width modulation. The controller may be configured to perform a calibration process before alternating between on and off periods. The controller may be configured to perform a calibration process immediately after the aerosol generator is switched on.The calibration process may include determining at least one calibration variable of the susceptor element, such as a conductance or resistance value, by supplying a first current to the inductor element. In particular, the controller may be configured to perform the calibration process before supplying a second current to the resistive heating element.

[0054] The control circuit may be configured to simultaneously supply a first current to the inductor element and a second current to the resistive heating element. Advantageously, this allows for the transfer of more thermal energy to the aerosol-forming substrate, generating a larger volume of aerosol, without causing either the susceptor or the resistive heating element to reach a temperature that could ignite any part of the aerosol-generating article. This can be particularly beneficial, for example, after the aerosol-generating system has been started up or when using the aerosol-generating system in a low-temperature environment.

[0055] Many methods exist for combining the induction heating of a susceptor with the heating of a resistance heating element. For example, the induction heating of the susceptor may be controlled to follow a specific profile throughout the course of the usage session, while the resistance heating of the resistance heating element may be controlled to follow a different profile throughout the course of the usage session. The profile may be selected to provide consistent aerosol delivery throughout the course of the usage session, as well as to provide heating for substantially all aerosol-forming substrates.

[0056] The control circuit may be configured to maintain the susceptor temperature at a target temperature or to follow a target temperature profile by adjusting a first current supplied to the inductor element. For example, the control circuit may be configured to maintain the susceptor element temperature at a susceptor target temperature or to follow a susceptor target temperature profile by adjusting a first current supplied to the inductor element.

[0057] The control circuit may be configured to maintain the temperature of the resistive heating element at a target temperature or to follow a target temperature profile by adjusting the second current supplied to the resistive heating element. For example, the control circuit may be configured to maintain the temperature of the resistive heating element at a resistive heating target temperature or to follow a resistive heating target temperature profile by adjusting the amplitude of the second current supplied to the resistive heating element.

[0058] The control circuit may be configured to adjust the amount of heat generated within the susceptor by the inductor element as a result of the alternating current by changing the magnitude of the alternating current during the operation of the device.

[0059] The control circuit may be configured to adjust the amount of heat generated in the susceptor by the inductor element as a result of the alternating current by adjusting the frequency of the alternating current during the operation of the device.

[0060] The inductor element may enclose the chamber at least partially. Advantageously, this can result in efficient heating of the susceptor element by the inductor element. The inductor element may enclose the chamber.

[0061] The resistance heating element may surround the chamber at least partially. Advantageously, this can lead to efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0062] The inductor element and the resistive heating element may surround the same longitudinal portion of the chamber.

[0063] The resistance heating element may be configured to heat the periphery of the chamber. Advantageously, if the inductor element and susceptor are configured to heat the central portion of the aerosol-forming substrate, this arrangement can ensure that no portion of the aerosol-forming substrate is overheated.

[0064] The resistance heating element may extend from the first end of the chamber to the second end of the chamber.

[0065] When an alternating magnetic field is generated in the chamber by an alternating current in an inductor coil, depending on the configuration of adjacent resistive heating elements, the alternating magnetic field may induce an alternating current in the adjacent resistive heating elements. The resistive heating elements may be configured such that the total current induced in them by the alternating magnetic field is substantially zero.

[0066] The resistive heating element may include at least one primary portion. The resistive heating element may include at least one secondary portion. The resistive heating element may be configured such that the current induced in at least one primary portion by the alternating magnetic field is approximately equal to and opposite to the current induced in at least one secondary portion by the alternating magnetic field.

[0067] The resistive heating element may form an electrical path from the positive terminal to the negative terminal of the control circuit. At least one primary portion may extend along the electrical path clockwise around the chamber toward the negative terminal of the control circuit when viewed from the first end of the chamber.

[0068] The second current can be considered to flow from the positive terminal of the control circuit to the negative terminal of the control circuit. At least one primary section may be arranged such that, when viewed from the first end of the chamber, the second current flows clockwise around the chamber within at least one primary section.

[0069] At least one secondary portion may extend along the electrical path toward the negative terminal of the control circuit in the opposite direction to at least one primary portion when viewed from the first end of the chamber. For example, at least one secondary portion may extend along the electrical path toward the negative terminal of the control circuit in a counterclockwise direction when viewed from the first end of the chamber.

[0070] At least one secondary section may be configured such that, when viewed from the first end of the chamber, the second current flows in the at least one secondary section in the opposite direction to the second current in the at least one primary section. For example, at least one secondary section may be configured such that, when viewed from the first end of the chamber, the second current flows in the at least one secondary section in a counterclockwise direction around the chamber.

[0071] The cumulative length of at least one primary part may be substantially equal to the cumulative length of at least one secondary part.

[0072] The alternating current induced within a resistive heating element can be particularly disadvantageous because the control circuit requires a filter to ensure that the alternating current induced within the resistive heating element does not damage any electronic components electrically connected to it. Advantageously, in the above configuration, the resistive heating element is positioned such that any alternating current induced within the resistive heating element toward the negative terminal of the control circuit is equal to the current induced within the resistive heating element toward the positive terminal of the control circuit. As a result, the total alternating current induced within the resistive heating element between the positive and negative terminals of the control circuit is at least significantly reduced, to approximately zero. This minimization of the total alternating current induced within the resistive heating element between the positive and negative terminals of the control circuit means that a filter is not required to ensure that the alternating current induced within the resistive heating element does not damage any electronic components electrically connected to it. Therefore, the complexity of the control circuit can be significantly reduced.

[0073] At least one primary part may be formed integrally with at least one secondary part.

[0074] The resistance heating element may include exactly one primary portion. The resistance heating element may include exactly one secondary portion. The primary and secondary portions may extend from the portion adjacent to the first end of the chamber to the portion adjacent to the second end of the chamber.

[0075] The primary and secondary sections may be electrically connected to the power supply at the second end of the chamber. The first end of the primary section may be electrically connected to the positive terminal of the control circuit. The first end of the secondary section may be electrically connected to the negative terminal of the control circuit.

[0076] The primary and secondary sections may be directly connected to each other adjacent to the first end of the chamber. In particular, the second end of the primary section, located opposite the first end of the primary section, may be directly connected to the second end of the secondary section, located opposite the first end of the secondary section.

[0077] The primary part may be formed integrally with the secondary part.

[0078] The primary and secondary parts may be wound together around the chamber such that they are substantially parallel to each other. The primary and secondary parts may be wound together in a helical manner around the chamber.

[0079] Advantageously, this arrangement allows for a clear implementation of the above concept and provides two co-wound sections such that the total induced AC current between the positive and negative terminals of the control circuit is at least significantly reduced to approximately zero.

[0080] The resistance heating element may be arranged in a meandering shape. The resistance heating element may include two filaments arranged in a meandering shape such that the two filaments are substantially parallel to each other. In this arrangement, the resistance heating element may include a plurality of alternating primary and secondary parts, as described above.

[0081] Advantageously, this arrangement makes it possible to implement the above concept that the total induced AC current within the serpentine resistance heating element between the positive and negative terminals of the control circuit is at least significantly reduced to approximately zero.

[0082] The resistance heating element may be folded or curved to at least partially enclose the chamber. Therefore, advantageously, the resistance heating element may be printed onto a substantially flat and planar substrate before being folded or curved to at least partially enclose the chamber. This may provide a simple and reliable method for manufacturing an aerosol generator. For example, the resistance heating element may be printed onto a substantially flat and planar polyimide substrate.

[0083] The inductor element may be an inductor coil. The inductor coil may be a helical coil. The resistive heating element may be a resistive heating coil. The resistive heating coil may be a helical coil. The resistive heating coil and the inductor coil may be wound together. Advantageously, this can result in a space-efficient arrangement in which the two separate heating systems can be positioned adjacent to the aerosol-forming substrate when the aerosol-forming article is received in the chamber.

[0084] The resistance heating coil may be wound around a winding axis. The inductor coil may be wound around the same winding axis as the resistance heating coil.

[0085] The aerosol generator may further include a jacket, which may at least partially define the chamber.

[0086] The resistive heating element may be positioned on the outer surface of the jacket. The resistive heating coil may be wound around the outer surface of the jacket. Advantageously, the resistive heating element does not come into contact with the outer surface of the aerosol-forming article when the aerosol-forming article is received into the chamber. This can protect the resistive heating element from damage when the aerosol-forming article is inserted into the chamber, and can reduce the likelihood of the aerosol-forming article overheating when a second current is supplied to the resistive heating element.

[0087] The inductor element may be positioned on the outer surface of the jacket. The inductor coil may be wound around the outer surface of the jacket. Advantageously, the inductor element does not come into contact with the outer surface of the aerosol-forming article when the aerosol-forming article is received into the chamber. This protects the inductor element from damage when the aerosol-forming article is inserted into the chamber.

[0088] The jacket may be a thermally conductive jacket. The thermal conductivity of the thermally conductive jacket shall be at least 20 Wm². -1 K -1 Preferably at least 30Wm -1 K -1 More preferably, at least 40 Wm -1 K -1 More preferably, about 80 Wm -1 K -1 Alternatively, this may be the case. Advantageously, the thermally conductive jacket ensures that heat is efficiently transferred from the resistance heating element to the aerosol-forming substrate.

[0089] The jacket may contain an electrical insulating material. The jacket may consist of an electrical insulating material. The jacket may contain a material having a relative permeability of 0.9 to 1.1, preferably 0.99 to 1.01. Therefore, the jacket may contain a material that is substantially transparent to the alternating magnetic field. Advantageously, the jacket may not substantially affect the alternating magnetic field induced in the chamber by the inductor element.

[0090] The jacket may contain ceramics. The ceramic may contain alumina. Advantageously, it has been found that alumina has suitable thermal properties to ensure efficient heat transfer from the resistance heating element to the aerosol-forming substrate. The ceramic may contain aluminum nitrate. Advantageously, it has been found that aluminum nitrate has suitable thermal properties to ensure efficient heat transfer from the resistance heating element to the aerosol-forming substrate.

[0091] The jacket may have a circular cross-section. The jacket may also have a substantially cylindrical shape. Therefore, advantageously, a cylindrical aerosol-forming article can be easily inserted into the chamber by the user in any orientation within 360 degrees.

[0092] The aerosol generator may further include a housing. The housing may at least partially enclose the chamber. The jacket may be housed within the housing.

[0093] The inductor element may be placed within the housing. The inductor element may be placed within the housing such that it at least partially encloses the jacket and the resistive heating element. Advantageously, the jacket and the resistive heating element may be manufactured together as a resistive heating assembly, and the resistive heating assembly may be insertable into the housing during manufacturing. This may allow for some degree of modularity during manufacturing, in that different resistive heating assemblies can be inserted into different housings with different inductor elements. Furthermore, the resistive heating assembly may be interchangeable with respect to the housing containing the inductor element.

[0094] The jacket may include a longitudinal axis. The jacket may include an inner surface. The inner surface may define a chamber. The jacket may include at least one groove defined on the inner surface of the jacket. At least one groove may extend parallel to the longitudinal axis.

[0095] An airflow channel may be defined between the aerosol-generating article and the jacket when the aerosol-generating article is received into the chamber. The airflow channel may extend from the distal end of the jacket to the proximal end of the jacket.

[0096] The airflow channel may be defined between the aerosol-generating article and at least one groove.

[0097] The airflow path may be defined from the distal end of the jacket through the airflow channel to the proximal end of the jacket when the aerosol-generating article is received into the chamber, or from the proximal end of the aerosol-generating article through the article to the distal end of the aerosol-generating article. Advantageously, this may provide a clear airflow path solution that does not require an airflow inlet defined through the housing.

[0098] The resistance heating coil may be wound around a winding axis that coincides with the long axis of the jacket. The inductor coil may be wound around a winding axis that coincides with the long axis of the jacket.

[0099] The inductor element may extend between the first and second ends. The electrical resistance between the first and second ends of the inductor element may be less than 250 milliohms, preferably less than 150 milliohms, and more preferably about 100 milliohms. Advantageously, the relatively low electrical resistance ensures that minimal power is dissipated as heat within the inductor element, since the inductor element cannot be configured to resistively heat the aerosol-forming substrate.

[0100] The resistive heating element may extend between the first and second ends. The electrical resistance between the first and second ends of the resistive heating element may be 100 milliohms to 2000 milliohms, preferably 150 to 1500 milliohms, and more preferably 200 to 1000 milliohms. Advantageously, a relatively high electrical resistance ensures that the maximum power is dissipated as heat within the resistive heating element, as the resistive heating element may be configured to resistively heat the aerosol-forming substrate.

[0101] The electrical resistance of the resistive heating element may be greater than that of the inductor element. The electrical resistance of the resistive heating element may be at least twice as great as that of the inductor element. The electrical resistance of the resistive heating element may be at least five times greater than that of the inductor element. The electrical resistance of the resistive heating element may be at least ten times greater than that of the inductor element.

[0102] The inductor element may include a first filament. The first filament may include a first cross-sectional area.

[0103] The first cross-sectional area may be defined by a first plane. The first cross-sectional area may be perpendicular to the direction of extension of the first filament. The first cross-sectional area may be perpendicular to the direction of extension of the first filament between the first and second ends of the inductor element. The orthogonality with respect to the first plane defining the first cross-sectional area may be perpendicular to the winding axis. The first cross-sectional area may be substantially constant between the first and second ends of the inductor element. Advantageously, this arrangement can be ensured that no portion of the inductor element between the first and second ends generates more heat via resistive heating than any other portion.

[0104] The first cross-sectional area may be perpendicular to the first current flow direction. The first cross-sectional area may be substantially rectangular in shape. Advantageously, it has been found that a rectangular cross-section increases the efficiency of the inductor element and reduces capacitance losses within the inductor element. Furthermore, the size of the aerosol generator can therefore be reduced by using a rectangular cross-section with respect to the inductor element. The first cross-sectional area may have a first width and a first thickness. The first width may be greater than the first thickness. The first width may be at least five times greater than the first thickness. For example, the first width may be at least ten times greater than the first thickness. Preferably, the first width may be at least fifteen times greater than the first thickness. The first width may be 0.1 mm to 5 mm. For example, the first width may be 0.5 mm to 4 mm. Preferably, the first width is 1 mm to 3 mm. The first thickness may be 0.02 mm to 1 mm. The first thickness may be 0.05 mm to 0.5 mm. The first thickness is preferably 0.05 mm to 0.2 mm. The first width may be parallel to the longitudinal axis of the jacket. The first width may be parallel to the winding axis of the inductor coil. The first thickness may be perpendicular to the longitudinal axis of the jacket. The first thickness may be perpendicular to the winding axis of the inductor coil. Advantageously, it has been found that this shape of the inductor element and these dimensions provide minimal heating of the inductor element via resistive heating, and also provide strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0105] The resistance heating element may include a second filament. The second filament may include a second cross-sectional area. The second cross-sectional area may be defined by the first plane. The second cross-sectional area may be defined by the same plane as the first cross-sectional area. The second cross-sectional area may be perpendicular to the direction of extension of the second filament. The second cross-sectional area may be perpendicular to the direction of extension of the second filament between the first and second ends of the resistance heating element. The orthogonality of the first plane defining the second cross-sectional area may be perpendicular to the winding axis. The second cross-sectional area may be substantially constant between the first and second ends of the resistance heating element. The first cross-sectional area may be larger than the second cross-sectional area. The first cross-sectional area may be at least five times larger than the second cross-sectional area. For example, the first cross-sectional area may be at least ten times larger than the second cross-sectional area. Preferably, the first cross-sectional area is at least fifteen times larger than the second cross-sectional area. It is even more preferable that the first cross-sectional area is at least 20 times larger than the second cross-sectional area. Advantageously, a larger ratio of the first cross-sectional area to the second cross-sectional area means that resistive heating within the inductor element is reduced, and that the majority of the resistive heating occurs within the resistive heating body as intended.

[0106] The second cross-sectional area may be perpendicular to the direction of the second current flow. The second cross-sectional area may be substantially circular in shape. The second cross-sectional area may have a diameter of 0.1 to 0.4 millimeters. Advantageously, it has been found that this shape and these dimensions of the resistance heating element allow for proper heating of the resistance heating element by resistance heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0107] The second cross-sectional area is preferably substantially rectangular in shape. Advantageously, it has been found that the rectangular cross-section enhances the efficiency of the resistance heating element by providing a larger contact area with the periphery of the aerosol-forming substrate or jacket. The second cross-sectional area may have a second width and a second thickness. The second width may be greater than the second thickness. The second width may be at least 5 times greater than the second thickness. For example, the second width may be at least 10 times greater than the second thickness. Preferably, the second width is at least 25 times greater than the second thickness. The second width may be 0.1 mm to 5 mm. For example, the second width may be 0.2 mm to 2 mm. Preferably, the second width is 0.5 mm to 0.7 mm. The second thickness may be 0.005 mm to 0.5 mm. The second thickness may be 0.01 mm to 0.1 mm. Preferably, the second thickness is 0.02 mm to 0.05 mm. The second width may be parallel to the longitudinal axis of the jacket. The second width may be parallel to the winding axis of the inductor coil. The second thickness may be perpendicular to the longitudinal axis of the jacket. The second thickness may be perpendicular to the winding axis of the inductor coil. Advantageously, it has been found that this shape and these dimensions of the resistance heating element provide efficient resistance heating of the periphery of the aerosol-forming substrate.

[0108] The inductor element may contain a metal. The inductor element may contain copper. The inductor element may be made of copper. Advantageously, it has been found that copper provides minimal heating of the inductor element via resistive heating, and also provides a strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0109] The resistance heating element may contain a metal. The resistance heating element may contain stainless steel. The resistance heating element may be made of stainless steel. Advantageously, stainless steel has been found to be a durable material with a suitable resistivity for maximizing the heating of the resistance heating element by resistance heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0110] The inductor element may contain materials different from those of the resistive heating element. The inductor element may be made of materials different from those of the resistive heating element.

[0111] According to a second aspect of this disclosure, an aerosol generator is provided, which is an aerosol generator A chamber for receiving at least a portion of an aerosol-generating article, An inductor element positioned adjacent to or within the chamber, A resistance heating element is provided, which is located adjacent to or inside the chamber. The inductor element comprises a first filament having a first cross-sectional area, the first cross-sectional area being defined by a first plane, The resistance heating element comprises a second filament including a second cross-sectional area, the second cross-sectional area also defined by the first plane. The first cross-sectional area is larger than the second cross-sectional area.

[0112] An aerosol generator according to a second embodiment may include any of the features described with respect to the first embodiment of this disclosure.

[0113] For example, the inductor element may enclose the chamber at least partially. Advantageously, this can result in efficient heating of the susceptor element by the inductor element. The inductor element may enclose the chamber.

[0114] The resistance heating element may surround the chamber at least partially. Advantageously, this can lead to efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0115] The inductor element and the resistive heating element may surround the same longitudinal portion of the chamber.

[0116] The resistance heating element may be configured to heat the periphery of the chamber. Advantageously, if the inductor element and susceptor are configured to heat the central portion of the aerosol-forming substrate, this arrangement can ensure that no portion of the aerosol-forming substrate is overheated.

[0117] The inductor element may be an inductor coil. The inductor coil may be a helical coil. The resistive heating element may be a resistive heating coil. The resistive heating coil may be a helical coil. The resistive heating coil and the inductor coil may be wound together. Advantageously, this can result in a space-efficient arrangement in which the two separate heating systems can be positioned adjacent to the aerosol-forming substrate when the aerosol-forming article is received in the chamber.

[0118] The resistance heating coil may be wound around a winding axis. The inductor coil may be wound around the same winding axis as the resistance heating coil.

[0119] The aerosol generator may further include a jacket, which may at least partially define the chamber.

[0120] The resistive heating element may be positioned on the outer surface of the jacket. The resistive heating coil may be wound around the outer surface of the jacket. Advantageously, the resistive heating element does not contact the outer surface of the aerosol-forming article when the aerosol-forming article is received within the chamber. Thereby, the resistive heating element can be protected from damage when the aerosol-forming article is inserted into the chamber, and the possibility that the aerosol-forming article is overheated when a second current is supplied to the resistive heating element can be reduced.

[0121] The inductor element may be positioned on the outer surface of the jacket. The inductor coil may be wound around the outer surface of the jacket. Advantageously, the inductor element does not contact the outer surface of the aerosol-forming article when the aerosol-forming article is received within the chamber. Thereby, the inductor element can be protected from damage when the aerosol-forming article is inserted into the chamber.

[0122] The jacket may be a thermally conductive jacket. The thermal conductivity of the thermally conductive jacket is at least 20 Wm -1 K -1 , preferably at least 30 Wm -1 K -1 and more preferably at least 40 Wm -1 K -1 and even more preferably about 80 Wm -1 K -1 . Advantageously, the thermally conductive jacket ensures that heat is efficiently transferred from the resistive heating element to the aerosol-forming substrate.

[0123] The jacket may comprise an electrically insulating material. The jacket may consist of an electrically insulating material. The jacket may comprise a material having a relative permeability of 0.9 to 1.1, preferably 0.99 to 1.01. Thus, the jacket may comprise a material that is substantially transparent to an alternating magnetic field. Thus, advantageously, the jacket may not substantially affect the alternating magnetic field induced within the chamber by the inductor element.

[0124] The jacket may contain ceramics. The ceramic may contain alumina. Advantageously, it has been found that alumina has suitable thermal properties to ensure efficient heat transfer from the resistance heating element to the aerosol-forming substrate. The ceramic may contain aluminum nitrate. Advantageously, it has been found that aluminum nitrate has suitable thermal properties to ensure efficient heat transfer from the resistance heating element to the aerosol-forming substrate.

[0125] The jacket may have a circular cross-section. The jacket may also have a substantially cylindrical shape. Therefore, advantageously, a cylindrical aerosol-forming article can be easily inserted into the chamber by the user in any orientation within 360 degrees.

[0126] The aerosol generator may further include a housing. The housing may at least partially enclose the chamber. The jacket may be housed within the housing.

[0127] The inductor element may be placed within the housing. The inductor element may be placed within the housing such that it at least partially encloses the jacket and the resistive heating element. Advantageously, the jacket and the resistive heating element may be manufactured together as a resistive heating assembly, and the resistive heating assembly may be insertable into the housing during manufacturing. This may allow for some degree of modularity during manufacturing, in that different resistive heating assemblies can be inserted into different housings with different inductor elements. Furthermore, the resistive heating assembly may be interchangeable with respect to the housing containing the inductor element.

[0128] The jacket may include a longitudinal axis. The jacket may include an inner surface. The inner surface may define a chamber. The jacket may include at least one groove defined on the inner surface of the jacket. At least one groove may extend parallel to the longitudinal axis.

[0129] An airflow channel may be defined between the aerosol-generating article and the jacket when the aerosol-generating article is received into the chamber. The airflow channel may extend from the distal end of the jacket to the proximal end of the jacket.

[0130] The airflow channel may be defined between the aerosol-generating article and at least one groove.

[0131] The airflow path may be defined from the distal end of the jacket through the airflow channel to the proximal end of the jacket when the aerosol-generating article is received into the chamber, or from the proximal end of the aerosol-generating article through the article to the distal end of the aerosol-generating article. Advantageously, this may provide a clear airflow path solution that does not require an airflow inlet defined through the housing.

[0132] The resistance heating coil may be wound around a winding axis that coincides with the long axis of the jacket. The inductor coil may be wound around a winding axis that coincides with the long axis of the jacket.

[0133] The inductor element may extend between the first and second ends. The electrical resistance between the first and second ends of the inductor element may be less than 250 milliohms, preferably less than 150 milliohms, and more preferably about 100 milliohms. Advantageously, the relatively low electrical resistance ensures that minimal power is dissipated as heat within the inductor element, since the inductor element cannot be configured to resistively heat the aerosol-forming substrate.

[0134] The resistive heating element may extend between the first and second ends. The electrical resistance between the first and second ends of the resistive heating element may be 100 milliohms to 2000 milliohms, preferably 150 to 1500 milliohms, and more preferably 200 to 1000 milliohms. Advantageously, a relatively high electrical resistance ensures that the maximum power is dissipated as heat within the resistive heating element, as the resistive heating element may be configured to resistively heat the aerosol-forming substrate.

[0135] The electrical resistance of the resistive heating element may be greater than that of the inductor element. The electrical resistance of the resistive heating element may be at least twice as great as that of the inductor element. The electrical resistance of the resistive heating element may be at least five times greater than that of the inductor element. The electrical resistance of the resistive heating element may be at least ten times greater than that of the inductor element.

[0136] The first cross-sectional area may be perpendicular to the direction of extension of the first filament. The first cross-sectional area may be perpendicular to the direction of extension of the first filament between the first and second ends of the inductor element. The orthogonality with respect to the first plane defining the first cross-sectional area may be perpendicular to the winding axis. The first cross-sectional area may be substantially constant between the first and second ends of the inductor element. Advantageously, this arrangement can be ensured that no portion of the inductor element between the first and second ends generates more heating via resistive heating than any other portion.

[0137] The first cross-sectional area may be perpendicular to the first current flow direction. The first cross-sectional area may be substantially rectangular in shape. Advantageously, it has been found that a rectangular cross-section increases the efficiency of the inductor element and reduces capacitance losses within the inductor element. Furthermore, the size of the aerosol generator can therefore be reduced by using a rectangular cross-section with respect to the inductor element. The first cross-sectional area may have a first width and a first thickness. The first width may be greater than the first thickness. The first width may be at least five times greater than the first thickness. For example, the first width may be at least ten times greater than the first thickness. Preferably, the first width may be at least fifteen times greater than the first thickness. The first width may be 0.1 mm to 5 mm. For example, the first width may be 0.5 mm to 4 mm. Preferably, the first width is 1 mm to 3 mm. The first thickness may be 0.02 mm to 1 mm. The first thickness may be 0.05 mm to 0.5 mm. The first thickness is preferably 0.05 mm to 0.2 mm. The first width may be parallel to the longitudinal axis of the jacket. The first width may be parallel to the winding axis of the inductor coil. The first thickness may be perpendicular to the longitudinal axis of the jacket. The first thickness may be perpendicular to the winding axis of the inductor coil. Advantageously, it has been found that this shape of the inductor element and these dimensions provide minimal heating of the inductor element via resistive heating, and also provide strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0138] The second cross-sectional area may be perpendicular to the direction of extension of the second filament. The second cross-sectional area may be perpendicular to the direction of extension of the second filament between the first and second ends of the resistance heating element. The orthogonality with respect to the first plane defining the second cross-sectional area may be perpendicular to the winding axis. The second cross-sectional area may be substantially constant between the first and second ends of the resistance heating element. The second cross-sectional area may be perpendicular to the direction of flow of the second current. The shape of the second cross-sectional area may be substantially circular. The second cross-sectional area may have a diameter of 0.1 mm to 0.4 mm. Advantageously, it has been found that this shape and these dimensions of the resistance heating element allow for proper heating of the resistance heating element by resistance heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0139] The second cross-sectional area is preferably substantially rectangular in shape. Advantageously, it has been found that the rectangular cross-section enhances the efficiency of the resistance heating element by providing a larger contact area with the periphery of the aerosol-forming substrate or jacket. The second cross-sectional area may have a second width and a second thickness. The second width may be greater than the second thickness. The second width may be at least 5 times greater than the second thickness. For example, the second width may be at least 10 times greater than the second thickness. Preferably, the second width is at least 25 times greater than the second thickness. The second width may be 0.1 mm to 5 mm. For example, the second width may be 0.2 mm to 2 mm. Preferably, the second width is 0.5 mm to 0.7 mm. The second thickness may be 0.005 mm to 0.5 mm. The second thickness may be 0.01 mm to 0.1 mm. Preferably, the second thickness is 0.02 mm to 0.05 mm. The second width may be parallel to the longitudinal axis of the jacket. The second width may be parallel to the winding axis of the inductor coil. The second thickness may be perpendicular to the longitudinal axis of the jacket. The second thickness may be perpendicular to the winding axis of the inductor coil. Advantageously, it has been found that this shape and these dimensions of the resistance heating element provide efficient resistance heating of the periphery of the aerosol-forming substrate.

[0140] The first cross-sectional area may be at least five times larger than the second cross-sectional area. For example, the first cross-sectional area may be at least ten times larger than the second cross-sectional area. Preferably, the first cross-sectional area is at least fifteen times larger than the second cross-sectional area. More preferably, the first cross-sectional area is at least twenty times larger than the second cross-sectional area. Advantageously, a larger ratio of the first cross-sectional area to the second cross-sectional area means that resistive heating within the inductor element is reduced, and that most of the resistive heating occurs within the resistive heating element as intended.

[0141] The inductor element may contain a metal. The inductor element may contain copper. The inductor element may be made of copper. Advantageously, it has been found that copper provides minimal heating of the inductor element via resistive heating, and also provides a strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0142] The resistance heating element may contain a metal. The resistance heating element may contain stainless steel. The resistance heating element may be made of stainless steel. Advantageously, stainless steel has been found to be a durable material with a suitable resistivity for maximizing the heating of the resistance heating element by resistance heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0143] The inductor element may contain materials different from those of the resistive heating element. The inductor element may be made of materials different from those of the resistive heating element.

[0144] The aerosol generator may include at least one power supply for providing power to the inductor element and the resistive heating element. The aerosol generator may also include a control circuit configured to control the power supply from at least one power supply to the inductor element and the resistive heating element.

[0145] The control circuit may be configured to supply a first current to the inductor element so that the inductor element generates an alternating magnetic field within the chamber.

[0146] The control circuit may be configured to supply a second current to the resistive heating element in order to heat the chamber.

[0147] The resistance heating element may extend from the first end of the chamber to the second end of the chamber.

[0148] When an alternating magnetic field is generated in the chamber by an alternating current in an inductor coil, depending on the configuration of adjacent resistive heating elements, the alternating magnetic field may induce an alternating current in the adjacent resistive heating elements. The resistive heating elements may be configured such that the total current induced in them by the alternating magnetic field is substantially zero.

[0149] The resistive heating element may include at least one primary portion. The resistive heating element may include at least one secondary portion. The resistive heating element may be configured such that the current induced in at least one primary portion by the alternating magnetic field is approximately equal to and opposite to the current induced in at least one secondary portion by the alternating magnetic field.

[0150] The resistive heating element may form an electrical path from the positive terminal to the negative terminal of the control circuit. At least one primary portion may extend along the electrical path clockwise around the chamber toward the negative terminal of the control circuit when viewed from the first end of the chamber.

[0151] The second current can be considered to flow from the positive terminal of the control circuit to the negative terminal of the control circuit. At least one primary section may be arranged such that, when viewed from the first end of the chamber, the second current flows clockwise around the chamber within at least one primary section.

[0152] At least one secondary portion may extend along the electrical path toward the negative terminal of the control circuit in the opposite direction to at least one primary portion when viewed from the first end of the chamber. For example, at least one secondary portion may extend along the electrical path toward the negative terminal of the control circuit in a counterclockwise direction when viewed from the first end of the chamber.

[0153] At least one secondary section may be configured such that, when viewed from the first end of the chamber, the second current flows in the at least one secondary section in the opposite direction to the second current in the at least one primary section. For example, at least one secondary section may be configured such that, when viewed from the first end of the chamber, the second current flows in the at least one secondary section in a counterclockwise direction around the chamber.

[0154] The cumulative length of at least one primary part may be substantially equal to the cumulative length of at least one secondary part.

[0155] The alternating current induced within a resistive heating element can be particularly disadvantageous because the control circuit requires a filter to ensure that the alternating current induced within the resistive heating element does not damage any electronic components electrically connected to it. Advantageously, in the above configuration, the resistive heating element is positioned such that any alternating current induced within the resistive heating element toward the negative terminal of the control circuit is equal to the current induced within the resistive heating element toward the positive terminal of the control circuit. As a result, the total alternating current induced within the resistive heating element between the positive and negative terminals of the control circuit is at least significantly reduced, to approximately zero. This minimization of the total alternating current induced within the resistive heating element between the positive and negative terminals of the control circuit means that a filter is not required to ensure that the alternating current induced within the resistive heating element does not damage any electronic components electrically connected to it. Therefore, the complexity of the control circuit can be significantly reduced.

[0156] At least one primary part may be formed integrally with at least one secondary part.

[0157] The resistance heating element may include exactly one primary portion. The resistance heating element may include exactly one secondary portion. The primary and secondary portions may extend from the portion adjacent to the first end of the chamber to the portion adjacent to the second end of the chamber.

[0158] The primary and secondary sections may be electrically connected to the power supply at the second end of the chamber. The first end of the primary section may be electrically connected to the positive terminal of the control circuit. The first end of the secondary section may be electrically connected to the negative terminal of the control circuit.

[0159] The primary and secondary sections may be directly connected to each other adjacent to the first end of the chamber. In particular, the second end of the primary section, located opposite the first end of the primary section, may be directly connected to the second end of the secondary section, located opposite the first end of the secondary section.

[0160] The primary part may be formed integrally with the secondary part.

[0161] The primary and secondary parts may be wound together around the chamber such that they are substantially parallel to each other. The primary and secondary parts may be wound together in a helical manner around the chamber.

[0162] Advantageously, this arrangement allows for a clear implementation of the above concept and provides two co-wound sections such that the total induced AC current between the positive and negative terminals of the control circuit is at least significantly reduced to approximately zero.

[0163] The resistance heating element may be arranged in a meandering shape. The resistance heating element may include two filaments arranged in a meandering shape such that the two filaments are substantially parallel to each other. In this arrangement, the resistance heating element may include a plurality of alternating primary and secondary parts, as described above.

[0164] Advantageously, this arrangement makes it possible to implement the above concept that the total induced AC current within the serpentine resistance heating element between the positive and negative terminals of the control circuit is at least significantly reduced to approximately zero.

[0165] The resistance heating element may be folded or curved to at least partially enclose the chamber. Therefore, advantageously, the resistance heating element may be printed onto a substantially flat and planar substrate before being folded or curved to at least partially enclose the chamber. This may provide a simple and reliable method for manufacturing an aerosol generator. For example, the resistance heating element may be printed onto a substantially flat and planar polyimide substrate.

[0166] According to a third aspect of this disclosure, an aerosol generator is provided, which is

[0167] A chamber for receiving at least a portion of an aerosol-generating article,

[0168] An inductor element positioned adjacent to or within the chamber,

[0169] A resistance heating element is provided, which is located adjacent to or inside the chamber.

[0170] The inductor element contains copper,

[0171] The resistance heating element includes stainless steel.

[0172] A third embodiment of the aerosol generator may include any of the features described with respect to the first and second embodiments of this disclosure.

[0173] For example, the inductor element may enclose the chamber at least partially. Advantageously, this can result in efficient heating of the susceptor element by the inductor element. The inductor element may enclose the chamber.

[0174] The resistance heating element may surround the chamber at least partially. Advantageously, this can lead to efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0175] The inductor element and the resistive heating element may surround the same longitudinal portion of the chamber.

[0176] The resistance heating element may be configured to heat the periphery of the chamber. Advantageously, if the inductor element and susceptor are configured to heat the central portion of the aerosol-forming substrate, this arrangement can ensure that no portion of the aerosol-forming substrate is overheated.

[0177] The inductor element may be an inductor coil. The inductor coil may be a helical coil. The resistive heating element may be a resistive heating coil. The resistive heating coil may be a helical coil. The resistive heating coil and the inductor coil may be wound together. Advantageously, this can result in a space-efficient arrangement in which the two separate heating systems can be positioned adjacent to the aerosol-forming substrate when the aerosol-forming article is received in the chamber.

[0178] The resistance heating coil may be wound around a winding axis. The inductor coil may be wound around the same winding axis as the resistance heating coil.

[0179] The aerosol generator may further include a jacket, which may at least partially define the chamber.

[0180] The resistive heating element may be positioned on the outer surface of the jacket. The resistive heating coil may be wound around the outer surface of the jacket. Advantageously, the resistive heating element does not come into contact with the outer surface of the aerosol-forming article when the aerosol-forming article is received into the chamber. This can protect the resistive heating element from damage when the aerosol-forming article is inserted into the chamber, and can reduce the likelihood of the aerosol-forming article overheating when a second current is supplied to the resistive heating element.

[0181] The inductor element may be positioned on the outer surface of the jacket. The inductor coil may be wound around the outer surface of the jacket. Advantageously, the inductor element does not come into contact with the outer surface of the aerosol-forming article when the aerosol-forming article is received into the chamber. This protects the inductor element from damage when the aerosol-forming article is inserted into the chamber.

[0182] The jacket may be a thermally conductive jacket. The thermal conductivity of the thermally conductive jacket shall be at least 20 Wm². -1 K -1 Preferably at least 30Wm -1 K -1 More preferably, at least 40 Wm -1 K -1 More preferably, about 80 Wm -1 K -1 Alternatively, this may be the case. Advantageously, the thermally conductive jacket ensures that heat is efficiently transferred from the resistance heating element to the aerosol-forming substrate.

[0183] The jacket may contain an electrical insulating material. The jacket may consist of an electrical insulating material. The jacket may contain a material having a relative permeability of 0.9 to 1.1, preferably 0.99 to 1.01. Therefore, the jacket may contain a material that is substantially transparent to the alternating magnetic field. Advantageously, the jacket may not substantially affect the alternating magnetic field induced in the chamber by the inductor element.

[0184] The jacket may contain ceramics. The ceramic may contain alumina. Advantageously, it has been found that alumina has suitable thermal properties to ensure efficient heat transfer from the resistance heating element to the aerosol-forming substrate. The ceramic may contain aluminum nitrate. Advantageously, it has been found that aluminum nitrate has suitable thermal properties to ensure efficient heat transfer from the resistance heating element to the aerosol-forming substrate.

[0185] The jacket may have a circular cross-section. The jacket may also have a substantially cylindrical shape. Therefore, advantageously, a cylindrical aerosol-forming article can be easily inserted into the chamber by the user in any orientation within 360 degrees.

[0186] The aerosol generator may further include a housing. The housing may at least partially enclose the chamber. The jacket may be housed within the housing.

[0187] The inductor element may be placed within the housing. The inductor element may be placed within the housing such that it at least partially encloses the jacket and the resistive heating element. Advantageously, the jacket and the resistive heating element may be manufactured together as a resistive heating assembly, and the resistive heating assembly may be insertable into the housing during manufacturing. This may allow for some degree of modularity during manufacturing, in that different resistive heating assemblies can be inserted into different housings with different inductor elements. Furthermore, the resistive heating assembly may be interchangeable with respect to the housing containing the inductor element.

[0188] The jacket may include a longitudinal axis. The jacket may include an inner surface. The inner surface may define a chamber. The jacket may include at least one groove defined on the inner surface of the jacket. At least one groove may extend parallel to the longitudinal axis.

[0189] An airflow channel may be defined between the aerosol-generating article and the jacket when the aerosol-generating article is received into the chamber. The airflow channel may extend from the distal end of the jacket to the proximal end of the jacket.

[0190] The airflow channel may be defined between the aerosol-generating article and at least one groove.

[0191] The airflow path may be defined from the distal end of the jacket through the airflow channel to the proximal end of the jacket when the aerosol-generating article is received into the chamber, or from the proximal end of the aerosol-generating article through the article to the distal end of the aerosol-generating article. Advantageously, this may provide a clear airflow path solution that does not require an airflow inlet defined through the housing.

[0192] The resistance heating coil may be wound around a winding axis that coincides with the long axis of the jacket. The inductor coil may be wound around a winding axis that coincides with the long axis of the jacket.

[0193] The inductor element may extend between the first and second ends. The electrical resistance between the first and second ends of the inductor element may be less than 250 milliohms, preferably less than 150 milliohms, and more preferably about 100 milliohms. Advantageously, the relatively low electrical resistance ensures that minimal power is dissipated as heat within the inductor element, since the inductor element cannot be configured to resistively heat the aerosol-forming substrate.

[0194] The resistive heating element may extend between the first and second ends. The electrical resistance between the first and second ends of the resistive heating element may be 100 milliohms to 2000 milliohms, preferably 150 to 1500 milliohms, and more preferably 200 to 1000 milliohms. Advantageously, a relatively high electrical resistance ensures that the maximum power is dissipated as heat within the resistive heating element, as the resistive heating element may be configured to resistively heat the aerosol-forming substrate.

[0195] The electrical resistance of the resistive heating element may be greater than that of the inductor element. The electrical resistance of the resistive heating element may be at least twice as great as that of the inductor element. The electrical resistance of the resistive heating element may be at least five times greater than that of the inductor element. The electrical resistance of the resistive heating element may be at least ten times greater than that of the inductor element.

[0196] The inductor element may include a first filament. The first filament may include a first cross-sectional area.

[0197] The first cross-sectional area may be defined by a first plane. The first cross-sectional area may be perpendicular to the direction of extension of the first filament. The first cross-sectional area may be perpendicular to the direction of extension of the first filament between the first and second ends of the inductor element. The orthogonality with respect to the first plane defining the first cross-sectional area may be perpendicular to the winding axis. The first cross-sectional area may be substantially constant between the first and second ends of the inductor element. Advantageously, this arrangement can be ensured that no portion of the inductor element between the first and second ends generates more heat via resistive heating than any other portion.

[0198] The first cross-sectional area may be perpendicular to the first current flow direction. The first cross-sectional area may be substantially rectangular in shape. Advantageously, it has been found that a rectangular cross-section increases the efficiency of the inductor element and reduces capacitance losses within the inductor element. Furthermore, the size of the aerosol generator can therefore be reduced by using a rectangular cross-section with respect to the inductor element. The first cross-sectional area may have a first width and a first thickness. The first width may be greater than the first thickness. The first width may be at least five times greater than the first thickness. For example, the first width may be at least ten times greater than the first thickness. Preferably, the first width may be at least fifteen times greater than the first thickness. The first width may be 0.1 mm to 5 mm. For example, the first width may be 0.5 mm to 4 mm. Preferably, the first width is 1 mm to 3 mm. The first thickness may be 0.02 mm to 1 mm. The first thickness may be 0.05 mm to 0.5 mm. The first thickness is preferably 0.05 mm to 0.2 mm. The first width may be parallel to the longitudinal axis of the jacket. The first width may be parallel to the winding axis of the inductor coil. The first thickness may be perpendicular to the longitudinal axis of the jacket. The first thickness may be perpendicular to the winding axis of the inductor coil. Advantageously, it has been found that this shape of the inductor element and these dimensions provide minimal heating of the inductor element via resistive heating, and also provide strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0199] The resistance heating element may include a second filament. The second filament may include a second cross-sectional area. The second cross-sectional area may be defined by the first plane. The second cross-sectional area may be defined by the same plane as the first cross-sectional area. The second cross-sectional area may be perpendicular to the direction of extension of the second filament. The second cross-sectional area may be perpendicular to the direction of extension of the second filament between the first and second ends of the resistance heating element. The orthogonality of the first plane defining the second cross-sectional area may be perpendicular to the winding axis. The second cross-sectional area may be substantially constant between the first and second ends of the resistance heating element. The first cross-sectional area may be larger than the second cross-sectional area. The first cross-sectional area may be at least five times larger than the second cross-sectional area. For example, the first cross-sectional area may be at least ten times larger than the second cross-sectional area. Preferably, the first cross-sectional area is at least fifteen times larger than the second cross-sectional area. It is even more preferable that the first cross-sectional area is at least 20 times larger than the second cross-sectional area. Advantageously, a larger ratio of the first cross-sectional area to the second cross-sectional area means that resistive heating within the inductor element is reduced, and that the majority of resistive heating occurs within the resistive heating element as intended. The second cross-sectional area may be perpendicular to the second current flow direction. The second cross-sectional area may be substantially circular in shape. The second cross-sectional area may have a diameter of 0.1 to 0.4 millimeters. Advantageously, it has been found that this shape and these dimensions of the resistive heating element allow for proper heating of the resistive heating element by resistive heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the resistive heating element.

[0200] The second cross-sectional area is preferably substantially rectangular in shape. Advantageously, it has been found that the rectangular cross-section enhances the efficiency of the resistance heating element by providing a larger contact area with the periphery of the aerosol-forming substrate or jacket. The second cross-sectional area may have a second width and a second thickness. The second width may be greater than the second thickness. The second width may be at least 5 times greater than the second thickness. For example, the second width may be at least 10 times greater than the second thickness. Preferably, the second width is at least 25 times greater than the second thickness. The second width may be 0.1 mm to 5 mm. For example, the second width may be 0.2 mm to 2 mm. Preferably, the second width is 0.5 mm to 0.7 mm. The second thickness may be 0.005 mm to 0.5 mm. The second thickness may be 0.01 mm to 0.1 mm. Preferably, the second thickness is 0.02 mm to 0.05 mm. The second width may be parallel to the longitudinal axis of the jacket. The second width may be parallel to the winding axis of the inductor coil. The second thickness may be perpendicular to the longitudinal axis of the jacket. The second thickness may be perpendicular to the winding axis of the inductor coil. Advantageously, it has been found that this shape and these dimensions of the resistance heating element provide efficient resistance heating of the periphery of the aerosol-forming substrate.

[0201] The inductor element may be made of copper. Advantageously, it has been found that copper provides minimal heating of the inductor element via resistive heating, and also provides a strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0202] The resistance heating element may be made of stainless steel. Advantageously, stainless steel has been found to be a durable material with a suitable resistivity for maximizing the heating of the resistance heating element by resistance heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0203] The inductor element may contain materials different from those of the resistive heating element. The inductor element may be made of materials different from those of the resistive heating element.

[0204] The aerosol generator may include at least one power supply for providing power to the inductor element and the resistive heating element. The aerosol generator may also include a control circuit configured to control the power supply from at least one power supply to the inductor element and the resistive heating element.

[0205] The control circuit may be configured to supply a first current to the inductor element so that the inductor element generates an alternating magnetic field within the chamber.

[0206] The control circuit may be configured to supply a second current to the resistive heating element in order to heat the chamber.

[0207] The resistance heating element may extend from the first end of the chamber to the second end of the chamber.

[0208] When an alternating magnetic field is generated in the chamber by an alternating current in an inductor coil, depending on the configuration of adjacent resistive heating elements, the alternating magnetic field may induce an alternating current in the adjacent resistive heating elements. The resistive heating elements may be configured such that the total current induced in them by the alternating magnetic field is substantially zero.

[0209] The resistive heating element may include at least one primary portion. The resistive heating element may include at least one secondary portion. The resistive heating element may be configured such that the current induced in at least one primary portion by the alternating magnetic field is approximately equal to and opposite to the current induced in at least one secondary portion by the alternating magnetic field.

[0210] The resistive heating element may form an electrical path from the positive terminal to the negative terminal of the control circuit. At least one primary portion may extend along the electrical path clockwise around the chamber toward the negative terminal of the control circuit when viewed from the first end of the chamber.

[0211] The second current can be considered to flow from the positive terminal of the control circuit to the negative terminal of the control circuit. At least one primary section may be arranged such that, when viewed from the first end of the chamber, the second current flows clockwise around the chamber within at least one primary section.

[0212] At least one secondary portion may extend along the electrical path toward the negative terminal of the control circuit in the opposite direction to at least one primary portion when viewed from the first end of the chamber. For example, at least one secondary portion may extend along the electrical path toward the negative terminal of the control circuit in a counterclockwise direction when viewed from the first end of the chamber.

[0213] At least one secondary section may be configured such that, when viewed from the first end of the chamber, the second current flows in the at least one secondary section in the opposite direction to the second current in the at least one primary section. For example, at least one secondary section may be configured such that, when viewed from the first end of the chamber, the second current flows in the at least one secondary section in a counterclockwise direction around the chamber.

[0214] The cumulative length of at least one primary part may be substantially equal to the cumulative length of at least one secondary part.

[0215] The alternating current induced within a resistive heating element can be particularly disadvantageous because the control circuit requires a filter to ensure that the alternating current induced within the resistive heating element does not damage any electronic components electrically connected to it. Advantageously, in the above configuration, the resistive heating element is positioned such that any alternating current induced within the resistive heating element toward the negative terminal of the control circuit is equal to the current induced within the resistive heating element toward the positive terminal of the control circuit. As a result, the total alternating current induced within the resistive heating element between the positive and negative terminals of the control circuit is at least significantly reduced, to approximately zero. This minimization of the total alternating current induced within the resistive heating element between the positive and negative terminals of the control circuit means that a filter is not required to ensure that the alternating current induced within the resistive heating element does not damage any electronic components electrically connected to it. Therefore, the complexity of the control circuit can be significantly reduced.

[0216] At least one primary part may be formed integrally with at least one secondary part.

[0217] The resistance heating element may include exactly one primary portion. The resistance heating element may include exactly one secondary portion. The primary and secondary portions may extend from the portion adjacent to the first end of the chamber to the portion adjacent to the second end of the chamber.

[0218] The primary and secondary sections may be electrically connected to the power supply at the second end of the chamber. The first end of the primary section may be electrically connected to the positive terminal of the control circuit. The first end of the secondary section may be electrically connected to the negative terminal of the control circuit.

[0219] The primary and secondary sections may be directly connected to each other adjacent to the first end of the chamber. In particular, the second end of the primary section, located opposite the first end of the primary section, may be directly connected to the second end of the secondary section, located opposite the first end of the secondary section.

[0220] The primary part may be formed integrally with the secondary part.

[0221] The primary and secondary parts may be wound together around the chamber such that they are substantially parallel to each other. The primary and secondary parts may be wound together in a helical manner around the chamber.

[0222] Advantageously, this arrangement allows for a clear implementation of the above concept and provides two co-wound sections such that the total induced AC current between the positive and negative terminals of the control circuit is at least significantly reduced to approximately zero.

[0223] The resistance heating element may be arranged in a meandering shape. The resistance heating element may include two filaments arranged in a meandering shape such that the two filaments are substantially parallel to each other. In this arrangement, the resistance heating element may include a plurality of alternating primary and secondary parts, as described above.

[0224] Advantageously, this arrangement makes it possible to implement the above concept that the total induced AC current within the serpentine resistance heating element between the positive and negative terminals of the control circuit is at least significantly reduced to approximately zero.

[0225] The resistance heating element may be folded or curved to at least partially enclose the chamber. Therefore, advantageously, the resistance heating element may be printed onto a substantially flat and planar substrate before being folded or curved to at least partially enclose the chamber. This may provide a simple and reliable method for manufacturing an aerosol generator. For example, the resistance heating element may be printed onto a substantially flat and planar polyimide substrate.

[0226] The present disclosure also provides an aerosol generating system. The aerosol generating system may comprise an aerosol generating device according to the present disclosure. For example, the aerosol generating system may comprise an aerosol generating device according to a first, second, or third aspect of the present disclosure. The aerosol generating system may comprise an aerosol generating article comprising an aerosol generating substrate. The aerosol generating article may be received within a chamber of the aerosol generating device.

[0227] According to a fourth aspect of this disclosure, an aerosol generating system is provided, which aerosol generating system an aerosol generator according to any of the above embodiments of the present disclosure, an aerosol generating article comprising an aerosol generating substrate, The aerosol-generating article is received into the chamber of the aerosol generator.

[0228] An aerosol-generating article may comprise one or more susceptors. An aerosol-generating article may comprise one or more susceptors as described above with respect to a first aspect of the present disclosure. For example, one or more susceptors may be in the form of at least one flake, or at least one rod, or at least one particle. One or more susceptors may be in the form of elongated particles. Elongated particles may be aligned with the long axis of the aerosol-generating article. Elongated particles may be aligned with the long axis of the aerosol-forming substrate. One or more susceptors may be in the form of one or more flakes made of susceptor material. An aerosol-generating article may comprise one or more flakes of an aerosol-forming substrate laminated with one or more flakes made of susceptor material. For example, an aerosol-generating article may comprise one or more flakes of tobacco material laminated with one or more flakes made of susceptor material.

[0229] The aerosol generator may include one or more susceptors. The aerosol generator may include one or more susceptors as described above in relation to the first aspect of the present disclosure. For example, one or more susceptors may be configured to be inserted into the aerosol generating substrate when an aerosol generating article is received into the chamber.

[0230] During operation, one or more susceptors may be heated by an inductor element. The aerosol generating substrate may contain tobacco material.

[0231] As described above with respect to the first embodiment, an airflow channel may be defined between the aerosol-generating article and the jacket, and the airflow channel extends from the distal end of the jacket to the proximal end of the jacket. The airflow channel may also be defined between the aerosol-generating article and at least one groove. The airflow path may be defined from the distal end of the jacket through the airflow channel to the proximal end of the jacket, or from the proximal end of the aerosol-generating article through the aerosol-generating article to the distal end of the aerosol-generating article.

[0232] As used herein, the term "aerosol-generating article" refers to an article comprising an aerosol-forming substrate having the ability to release volatile compounds capable of forming aerosols. Aerosol-generating articles may be disposable.

[0233] The Disclosure also provides a method for generating an aerosol by controlling an aerosol generating system. The aerosol generating system may comprise any aerosol generating system according to the Disclosure. For example, the aerosol generating system may comprise an aerosol generating article comprising an aerosol generating substrate. The aerosol generating system may comprise an aerosol generating device. The aerosol generating device may be in any of the above embodiments of the Disclosure. For example, the aerosol generating device may comprise a chamber for receiving at least a portion of the aerosol generating article. The aerosol generating device may further comprise an inductor element located adjacent to or within the chamber. The aerosol generating device may further comprise a resistive heating element located adjacent to or within the chamber. The aerosol generating device may further comprise at least one power source for supplying power to the inductor element and the resistive heating element. The aerosol generating device may further comprise a control circuit configured to control the power supply from at least one power source to the inductor element and the resistive heating element. The method may comprise the step of supplying a first current to an inductor element such that the inductor element generates an alternating magnetic field within the chamber. The method may include the step of providing a second current to the resistive heating element in order to resistively heat the resistive heating element.

[0234] According to a fifth aspect of this disclosure, a method is provided for generating an aerosol by controlling an aerosol generating system, the system being an aerosol generating article containing an aerosol generating substrate, an aerosol generator comprising an aerosol generator having a chamber for receiving at least a portion of an aerosol generating article, The aerosol generator is An inductor element positioned adjacent to or within the chamber, A resistance heating element positioned adjacent to or inside the chamber, At least one power supply for providing power to an inductor element and a resistive heating element, The system further comprises a control circuit configured to control the power supply from at least one power source to an inductor element and to a resistive heating element, The method is, A step of providing a first current to an inductor element so that the inductor element generates an alternating magnetic field within the chamber, The process includes the step of providing a second current to a resistive heating element in order to resistively heat the resistive heating element.

[0235] Providing a first current to the inductor element so that the inductor element generates an alternating magnetic field within the chamber may include heating one or more susceptors by the inductor element. Therefore, advantageously, the aerosol-forming substrate within the aerosol-generating article can be efficiently heated both externally and internally.

[0236] The method may further include adjusting the amount of heating provided by induction heating by adjusting a first current supplied to an inductor element. The method may further include adjusting the amount of heating provided by resistive heating by adjusting a second current supplied to a resistive heating element. Therefore, advantageously, the method avoids both overheating and underheating of any part of the aerosol-forming substrate, thereby resulting in more efficient aerosol generation without burning the aerosol-forming substrate.

[0237] The first current may be an alternating current. The alternating current may have a first frequency. The method may further include not providing a second current to the inductor element. The method may further include not providing a direct current to the inductor element. The method may further include supplying only the first current to the inductor element. Advantageously, this may result in minimal resistive heating of the inductor element, thereby reducing the risk of overheating or burning of the peripheral portion of the aerosol-forming substrate.

[0238] An aerosol-forming article may comprise one or more susceptors. Each of the susceptors may be in the form of at least one strip, or at least one rod, or at least one particle. Advantageously, the structure of an aerosol generator can be simplified because the aerosol generator does not need to include susceptor elements. Each of the susceptors may be in the form of elongated particles. The elongated particles may be aligned along the long axis of the aerosol-forming article. The elongated particles may also be aligned along the long axis of the aerosol-forming substrate. Each of the susceptors may be in the form of one or more strips made of susceptor material. An aerosol-forming article may comprise one or more strips of an aerosol-forming substrate laminated with one or more strips made of susceptor material. For example, an aerosol-forming article may comprise one or more strips of tobacco material laminated with one or more strips made of susceptor material.

[0239] The aerosol generator may comprise one or more susceptors. Each of the susceptors may be in the form of at least one blade or at least one pin. Advantageously, each of the susceptors may be reused with multiple aerosol-forming articles. Each of the susceptors may be configured to be inserted into the aerosol-generating substrate when the aerosol-generating article is received into the chamber. Advantageously, this may allow for a simpler and more sustainable configuration when using the aerosol-forming article.

[0240] The second current may be a direct current. The method may further include not supplying the first current to the resistive heating element. The method may further include not supplying an alternating current to the resistive heating element. The method may further include supplying only the second current to the resistive heating element. Advantageously, this may mean that the resistive heating element does not have a magnetic interaction with the inductor element.

[0241] The power supply may comprise a first DC power supply. Advantageously, a suitable range of DC power supplies may be suitable for use in an aerosol generator. The first DC power supply may be a battery. The control circuit may comprise a DC / AC converter connected to the first DC power supply. The method may further include supplying power from the first DC power supply to both the resistive heating element and the inductive element. Advantageously, power can be supplied to both the resistive heating element and the inductive element using a single DC power supply.

[0242] The DC / AC converter may include a Class E power amplifier comprising a first transistor switch and an LC load network.

[0243] The method may further include providing a second current to the resistive heating element so that the resistive heating element is heated to at least 80°C. Advantageously, heating the resistive heating element to at least 80°C may ensure that the resistive heating element adequately heats the aerosol-forming substrate so that vapor can be generated. The method may further include providing a second current to the resistive heating element so that the resistive heating element is heated not to exceed 210°C. Advantageously, heating the resistive heating element not to exceed 210°C may ensure that the resistive heating element does not burn or char the aerosol-forming substrate, thereby ensuring that no aerosol is generated that produces undesirable compounds and causes the user to experience a burnt taste.

[0244] The method may further include providing a first current to the inductor element and a second current to the resistive heating element at different times.

[0245] The method may further include providing a first current to an inductor element and then providing a second current to a resistive heating element. The method may further include providing a first current to an inductor element over a first time period. The method may further include providing a second current to a resistive heating element over a second time period following the first time period. Advantageously, the aerosol-forming substrate may be heterogeneous, and different parts of the aerosol-forming substrate may be heated at different times by heating the aerosol-forming substrate by induction heating followed by resistance heating. Because the aerosol-forming substrate may be heterogeneous, aerosols having aerosol properties may be generated at different times.

[0246] The method may further include providing a second current to a resistive heating element, and then providing a first current to an inductor element. The method may further include providing a second current to a resistive heating element over a first time period. The method may further include providing a first current to an inductor element over a second time period following the first time period. Advantageously, the aerosol-forming substrate may be heterogeneous, and different parts of the aerosol-forming substrate may be heated at different times by heating the aerosol-forming substrate by resistive heating followed by induction heating. Because the aerosol-forming substrate may be heterogeneous, aerosols having aerosol properties may be generated at different times.

[0247] The method may further include detecting when a user is inhaling smoke on the system. For example, the control circuit may be coupled to a pressure sensor, which is configured to detect a pressure drop when a user is inhaling smoke on the system. When the pressure sensor detects a pressure drop when a user is inhaling smoke on the system, the method may further include supplying power to an inductor element or a resistive heating element, or to both an inductor element and a resistive heating element. For example, the method may further include initiating a first time period in response to a user inhaling smoke on the system.

[0248] The control circuit may include a user-activatable trigger. For example, the user-activatable trigger may include a button or a switch. The method may further include initiating a first time period in response to the activation of the user-activatable trigger.

[0249] The method is, The system has performed a predetermined number of smoke inhalations, or A predetermined amount of time has elapsed since the first smoke extraction on the system, or A user-activated trigger has been activated, or This may further include ending the first time period and starting the second time period in response to any one or more of the above-mentioned combinations. The method may further include providing a first current to an inductor element and a second current to a resistive heating element in an alternating sequence. Advantageously, alternating between induction heating and resistive heating may be beneficial to avoid overheating of any portion of the aerosol-forming substrate. The method may further include the control circuit receiving an inductor feedback signal from an inductor element and a resistive heating feedback signal from a resistive heating element. For example, the method may further include the microcontroller receiving an inductor feedback signal from an inductor element and a resistive heating feedback signal from a resistive heating element. The inductor feedback signal may include at least one of voltage, current, or conductance. For example, the inductor feedback signal may include voltage and current. The resistive heating feedback signal may include at least one of voltage, current, or conductance. For example, the resistive heating feedback signal may include voltage and current.

[0250] The method may further include the control circuit providing a first current to the inductor element based on an inductor feedback signal. The method may further include the control circuit providing a second current to the resistive heating element based on a resistive heating feedback signal. The inductor feedback signal may depend on the temperature of the susceptor. The resistive heating feedback signal may depend on the temperature of the resistive heating element.

[0251] The method may further include adjusting a first current supplied to an inductor element depending on an inductor feedback signal. The method may further include determining the temperature of the inductor element depending on an inductor feedback signal. The method may further include maintaining the temperature of a susceptor element at a susceptor target temperature or following a target temperature profile by adjusting a first current supplied to an inductor element depending on an inductor feedback signal.

[0252] The method may further include adjusting a second current supplied to the resistive heating element depending on a resistive heating feedback signal. The method may further include determining the temperature of the resistive heating element depending on the resistive heating feedback signal. The method may further include maintaining the temperature of the resistive heating element at a resistive heating target temperature or following a resistive heating target temperature profile by adjusting the second current supplied to the resistive heating element depending on the resistive heating feedback signal.

[0253] When an alternating magnetic field is generated by supplying an alternating current to an inductor coil, the alternating magnetic field may induce an alternating current in the resistive heating element. Therefore, when a second current is supplied to the resistive heating element and the first current is supplied to the inductor element at the same time, the alternating current induced in the resistive heating element may affect the resistive heating feedback signal provided to the control circuit. For example, the alternating current induced in the resistive heating element may modify the resistive heating feedback signal provided to the control circuit. This may affect the control circuit's ability to accurately determine the temperature of the resistive heating element, and therefore the method's ability to maintain the temperature of the resistive heating element at a resistive heating target temperature or to make it follow a resistive heating target temperature profile.

[0254] Therefore, the method may further include preventing the supply of a second current to the resistive heating element when a first current is supplied to the inductor element. For example, the method may further include preventing the supply of a direct current to the resistive heating element when an alternating current is supplied to the inductor element. Advantageously, if the method further includes preventing the supply of a second current to the resistive heating element when a first current is supplied to the inductor element, the induced alternating current does not affect the resistive heating feedback signal. Thus, the method can determine the temperature of the resistive heating element more accurately.

[0255] Similarly, the method may further include preventing the supply of the first current to the inductor element when the second current is supplied to the resistive heating element. The method may further include preventing the simultaneous supply of the first current to the inductor element and the second current to the resistive heating element.

[0256] The method may further include providing a first current to the inductor element during the ON period and preventing the provision of the first current to the inductor element during the OFF period. The method may further include alternating between the ON period and the OFF period.

[0257] Specifically, the method may further include providing a switching voltage to a DC / AC converter to control a first current supplied to an inductor element. In particular, the method may further include supplying a switching voltage to a field-effect transistor of the DC / AC converter to control a first current supplied to an inductor element. The switching voltage may have a rectangular profile. The switching voltage may include alternating on periods in which a first current is supplied to the inductor element and off periods in which the supply of the first current to the inductor element is prevented.

[0258] The method may further include controlling the temperature of the susceptor element by adjusting the length of the on-period. For example, the method may further include maintaining the temperature of the susceptor element at a susceptor target temperature or following a susceptor target temperature profile by adjusting the length of the on-period, for example by using pulse width modulation.

[0259] The method may further include supplying a first current to the inductor element in one or more pulses during each ON period. The pulses may include a plurality of separate pulses. The method may further include blocking the supply of the first current to the inductor element when not in pulse mode.

[0260] The method may further include controlling the temperature of the susceptor element by adjusting the pulse during each on-period. For example, the method may further include controlling the temperature of the susceptor element by using pulse width modulation. The method may further include controlling the temperature of the susceptor element by adjusting one or more of the duration of each pulse, the number of each pulse, or the time gap between adjacent pulses during each on-period. For example, the method may further include maintaining the temperature of the susceptor element at the susceptor target temperature or following the susceptor target temperature profile by adjusting the pulse during each on-period.

[0261] The pulse may occupy a proportion of each on-period. For example, the pulse may occupy 100% of each on-period such that a first current is supplied to the inductor element over the entire duration of each on-period during each on-period. As another example, the pulse may occupy 50% of each on-period such that a first current is supplied to the inductor element over half of the duration of each on-period during each on-period. The method may further include controlling the temperature of the susceptor element by adjusting the proportion that the pulse occupies in each on-period. For example, the method may further include maintaining the temperature of the susceptor element at the susceptor target temperature or following the susceptor target temperature profile by adjusting the proportion that the pulse occupies in each on-period.

[0262] The on-period may have a length of 500 milliseconds to 1 millisecond. The on-period preferably has a length of 100 milliseconds to 5 milliseconds. More preferably, the on-period has a length of 50 milliseconds to 10 milliseconds. Even more preferably, the on-period has a length of about 20 milliseconds.

[0263] The off period may be 500 milliseconds to 1 millisecond in length. The off period is preferably 200 milliseconds to 10 milliseconds in length. The off period is more preferably 100 milliseconds to 50 milliseconds in length. The off period is still more preferably about 70 milliseconds in length.

[0264] The method may further include providing a second current to the resistive heating element during the off period. In particular, the method may further include providing a second current to the resistive heating element only during the off period.

[0265] The method may further include controlling the temperature of the resistive heating element by adjusting the length of the off period. For example, the method may further include maintaining the temperature of the resistive heating element at a resistive heating target temperature or following a resistive heating target temperature profile by adjusting the length of the off period. For example, by using pulse width modulation.

[0266] The method may further include providing the second current to the resistive heating element in one or more pulses during each off period. The pulses may include a plurality of distinct pulses. The method may further include blocking the supply of the second current to the resistive heating element when not in the pulses.

[0267] The method may further include controlling the temperature of the resistive heating element by adjusting the pulses during each off period. For example, the method may further include controlling the temperature of the resistive heating element by using pulse width modulation. The method may further include controlling the temperature of the resistive heating element by adjusting one or more of the duration of each pulse, the number of each pulse, or the time gap between adjacent pulses during each off period. For example, the method may further include maintaining the temperature of the resistive heating element at a resistive heating target temperature or following a resistive heating target temperature profile by adjusting the pulses during each off period.

[0268] The pulse may occupy a proportion of each off period. For example, the pulse may occupy 100% of each off period so that a second current is supplied to the resistive heating element for the entire duration of each off period. Alternatively, the pulse may occupy 50% of each off period so that a second current is supplied to the resistive heating element for half the duration of each off period. The method may further include controlling the temperature of the resistive heating element by adjusting the proportion of each off period occupied by the pulse. For example, the method may further include maintaining the temperature of the resistive heating element at a resistive heating target temperature or following a resistive heating target temperature profile by adjusting the proportion of each off period occupied by the pulse.

[0269] The method may further include supplying a second current to the resistive heating element over a reduced time period, the reduced time period being shorter than the off period. Advantageously, by supplying a second current to the resistive heating element over a reduced time period shorter than the off period during the off period, the control circuit can avoid any overlap between the first current supplied to the inductor element and the second current supplied to the resistive heating element. Advantageously, including a time gap between the reduced time period and the period during which the first current is supplied to the inductor element, because the alternating current induced in the resistive heating element cannot instantaneously drop to zero when the first current supplied to the inductor element is stopped, can reduce noise in the resistive heating feedback signal caused by any alternating current induced in the resistive heating element. Also advantageously, the method may further include controlling the temperature of the resistive heating element by adjusting the length of the reduced time period. For example, the method may further include maintaining the temperature of the resistive heating element at a resistive heating target temperature or following a resistive heating target temperature profile by adjusting the length of the reduced time period. The method may further include controlling the temperature of the resistive heating element by adjusting the length of the time gap between the reduced time period and the on period. For example, the method may further include maintaining the temperature of the resistive heating element at a resistive heating target temperature or following a resistive heating target temperature profile by adjusting the length of the time gap between the reduced time period and the on period. This allows the control circuit to maintain the temperature of the resistive heating element at a resistive heating target temperature or follow a resistive heating target temperature profile using pulse width modulation.

[0270] The method may further include performing a calibration process before alternating between on and off periods. The method may further include performing a calibration process immediately after the aerosol generator is switched on. The calibration process may include determining at least one calibration variable of a susceptor element, such as a conductance or resistance value, by providing a first current to the inductor element. In particular, the method may further include performing a calibration process before providing a second current to the resistive heating element.

[0271] The method may further include simultaneously supplying a first current to an inductor element and a second current to a resistive heating element. Advantageously, this mode of operation may supply maximum power to the aerosol-forming substrate in order to rapidly heat the aerosol-forming substrate. This may be particularly beneficial, for example, after the aerosol-generating system has been started up or when using the aerosol-generating system in a low-temperature environment.

[0272] The method may further include, after the device is started, first supplying a first current to the inductor element, and then supplying a second current to the resistive heating element. Advantageously, the aerosol-forming substrate may be non-uniform, and different parts of the aerosol-forming substrate may be heated at different times by heating the aerosol-forming substrate by induction heating followed by resistive heating. Because the aerosol-forming substrate may be non-uniform, aerosols having aerosol properties may be generated at different times.

[0273] The method may further include adjusting the amount of heating provided by induction heating by adjusting the frequency of the first current while the device is in operation.

[0274] The method may further include maintaining the susceptor temperature at a target temperature or following a target temperature profile by adjusting a first current supplied to the inductor element. For example, the method may further include maintaining the susceptor temperature at a susceptor target temperature or following a susceptor target temperature profile by adjusting the amplitude of the first current supplied to the inductor element.

[0275] The method may further include maintaining the temperature of the resistive heating element at a target temperature or following a target temperature profile by adjusting a second current supplied to the resistive heating element. For example, the method may further include maintaining the temperature of the resistive heating element at a resistive heating target temperature or following a resistive heating target temperature profile by adjusting the amplitude of the second current supplied to the resistive heating element.

[0276] Advantageously, the temperature profiles of the resistive heating element and the inductor element may be controlled independently.

[0277] According to a sixth aspect of this disclosure, an aerosol generator is provided, which is an aerosol generator A chamber for receiving at least a portion of an aerosol-generating article, Internal heater, External heater and, At least one power supply for providing power to the internal heater and the external heater, A control circuit configured to control the power supply from at least one power source to an internal heater and to an external heater, The control circuit is further configured to block the power supply to one of the external heaters or the internal heaters when power is being supplied to the other of the external heaters or the internal heaters.

[0278] Advantageously, by blocking the power supply to one of the external or internal heaters while power is being supplied to the other, the aerosol generator can utilize the energy stored in at least one power source in a more efficient manner, which may allow the user to have a longer aerosol generation experience. Simultaneous power supply from a power source to two separate internal and external heaters has been found to be detrimental to the efficiency of at least one power source.

[0279] The control circuit may be configured to block power supply to the external heater when power is being supplied to the internal heater. The control circuit may be configured to control power supply to the external heater depending on the power profile supplied to the internal heater. For example, the control circuit may be configured to block power supply to the external heater when power is being supplied to the internal heater, and not to block power supply to the external heater when power is not being supplied to the internal heater. In other words, the control circuit may be configured to allow power supply to the external heater when power is not being supplied to the internal heater.

[0280] The control circuit may be configured to block the power supply to the internal heater when power is being supplied to the external heater. The control circuit may be configured to control the power supply to the internal heater depending on the power profile supplied to the external heater. For example, the control circuit may be configured to block the power supply to the internal heater when power is being supplied to the external heater, and not to block the power supply to the internal heater when power is not being supplied to the external heater. In other words, the control circuit may be configured to allow the power supply to the internal heater when power is not being supplied to the external heater.

[0281] The internal heater may be configured to generate heat from an internal position within the chamber. The internal heater may be configured to heat the aerosol generating article from an internal position within the aerosol generating article when at least a portion of the aerosol generating article is received within the chamber. In particular, the internal heater may be configured to heat the aerosol generating article from an internal position within the aerosol forming substrate when at least a portion of the aerosol generating article is received within the chamber.

[0282] The external heater may be configured to generate heat from an external position outside the chamber. The external heater may be configured to heat the aerosol generating article from an external position outside the aerosol generating article when at least a portion of the aerosol generating article is received within the chamber. In particular, the external heater may be configured to heat the aerosol generating article from an external position outside the aerosol generating substrate when at least a portion of the aerosol generating article is received within the chamber.

[0283] The control circuit may be configured to provide a first current to the internal heater.

[0284] The control circuit may be configured to provide a second current to the external heater.

[0285] The power supply may comprise a first DC power supply. Advantageously, a range of suitable DC power supplies may be suitable for use in the aerosol generating device. The first DC power supply may be a battery. The control circuit may comprise a DC / AC converter connected to the first DC power supply. Thus, advantageously, a single DC power supply may be used to supply power to both the external heater and the internal heater.

[0286] The DC / AC converter may comprise a class E power amplifier including a first transistor switch and an LC load network.

[0287] The control circuit may be configured to supply a first current to the internal heater and a second current to the external heater at different times.

[0288] For example, the control circuit may be configured to supply a first current to an internal heater, and then a second current to an external heater. The control circuit may be configured to supply a first current to the internal heater over a first time period. The control circuit may be configured to supply a second current to the external heater over a second time period following the first time period. Advantageously, the aerosol-forming substrate may be heterogeneous, and different parts of the aerosol-forming substrate may be heated at different times by heating the aerosol-forming substrate from the inside and then from the outside. Because the aerosol-forming substrate may be heterogeneous, aerosols with aerosol properties may be generated at different times.

[0289] The control circuit may be configured to supply a second current to an external heater, and then to supply a first current to an internal heater. The control circuit may be configured to supply a second current to an external heater over a first time period. The control circuit may be configured to supply a first current to an internal heater over a second time period following the first time period. Advantageously, the aerosol-forming substrate may be non-uniform, and different parts of the aerosol-forming substrate may be heated at different times by heating the aerosol-forming substrate by resistance heating followed by induction heating. Because the aerosol-forming substrate may be non-uniform, aerosols with aerosol properties may be generated at different times.

[0290] The control circuit may be configured to detect when a user is inhaling smoke on the system. For example, the control circuit may be coupled to a pressure sensor, which is configured to detect a pressure drop when a user is inhaling smoke on the system. The control circuit may be configured to supply power to an internal heater or an external heater, or to both internal and external heaters, when the pressure sensor detects a pressure drop when a user is inhaling smoke on the system. For example, the control circuit may be configured to initiate a first time period in response to a user inhaling smoke on the system.

[0291] The control circuit may include a user-activatable trigger. For example, the user-activatable trigger may be a button or a switch. The control circuit may be configured to start a first time period in response to the activation of the user-activatable trigger.

[0292] The control circuit is, The system has performed a predetermined number of smoke inhalations, or A predetermined amount of time has elapsed since the first smoke extraction on the system, or A user-activated trigger has been activated, or The system may be configured to terminate the first time period and begin the second time period in response to any one or more of the above-mentioned combinations.

[0293] The control circuit may be configured to provide a first current to the internal heater and a second current to the external heater in an alternating sequence. Advantageously, alternating internal and external heating may be beneficial in preventing any portion of the aerosol-forming substrate from overheating.

[0294] The control circuit may include a microcontroller. The control circuit may be configured to receive internal heating feedback signals from an internal heater and external heating feedback signals from an external heater. For example, the microcontroller may be configured to receive internal heating feedback signals from an internal heater and external heating feedback signals from an external heater.

[0295] The internal heating feedback signal may include at least one of voltage, current, or conductance. For example, the internal heating feedback signal may include voltage and current. The external heating feedback signal may include at least one of voltage, current, or conductance. For example, the external heating feedback signal may include voltage and current.

[0296] The control circuit may be configured to supply a first current to the internal heater based on an internal heating feedback signal. The control circuit may be configured to supply a second current to the external heater based on an external heating feedback signal. The internal heating feedback signal may depend on the temperature of the internal heater components. The external heating feedback signal may depend on the temperature of the external heater components.

[0297] The control circuit may be configured to adjust a first current supplied to the internal heater depending on an internal heating feedback signal. The control circuit may be configured to determine the temperature of the internal heater components depending on the internal heating feedback signal. By adjusting the first current supplied to the internal heater depending on the internal heating feedback signal, the control circuit may be configured to maintain the temperature of the internal heater components at an internal heater target temperature or to follow an internal heater target temperature profile.

[0298] The control circuit may be configured to adjust a second current supplied to the external heater depending on an external heating feedback signal. The control circuit may be configured to determine the temperature of the external heater depending on an external heating feedback signal. By adjusting the second current supplied to the external heater depending on an external heating feedback signal, the control circuit may be configured to maintain the temperature of the components of the external heater at an external heater target temperature or to follow an external heater target temperature profile.

[0299] The control circuit may be configured to supply a first current to the internal heater during the ON period and to prevent the supply of the first current to the internal heater during the OFF period. The control circuit may be configured to supply a second current to the external heater during the OFF period and to prevent the supply of the second current to the external heater during the ON period. The control circuit may be configured to alternate between ON and OFF periods.

[0300] The microcontroller may be configured to supply a switching voltage to control circuit components in order to control a first current supplied to the internal heater. Specifically, in the embodiments described below in which the internal heater has an inductor element, the microcontroller may be configured to supply a switching voltage to a DC / AC converter in order to control a first current supplied to the internal heater. In particular, the microcontroller may be configured to supply a switching voltage to the field-effect transistor of the DC / AC converter in order to control a first current supplied to the internal heater.

[0301] The microcontroller may be configured to supply a switching voltage to control circuit components in order to control a second current supplied to an external heater. Specifically, in the embodiments described below in which the external heater has an inductor element, the microcontroller may be configured to supply a switching voltage to a DC / AC converter in order to control a second current supplied to the external heater. In particular, the microcontroller may be configured to supply a switching voltage to the field-effect transistor of the DC / AC converter in order to control a second current supplied to the external heater.

[0302] The switching voltage may have a rectangular profile.

[0303] The switching voltage may include alternating on periods in which a first current is supplied to the internal heater and off periods in which the supply of the first current to the internal heater is prevented. The control circuit may be configured to prevent the supply of a second current to the external heater during the on period.

[0304] The switching voltage may include alternating off periods in which a second current is supplied to the external heater and on periods in which the supply of the second current to the external heater is prevented. The control circuit may be configured to prevent the supply of the first current to the internal heater during the on periods.

[0305] The temperature of the internal heater components may be controlled by adjusting the length of the on-time. For example, the control circuit may be configured to adjust the length of the on-time to maintain the temperature of the internal heater components at the internal heater target temperature or to follow the internal heater target temperature profile.

[0306] The control circuit may be configured to supply a first current to the internal heater in one or more pulses during each ON period. The pulses may consist of multiple separate pulses. The control circuit may be configured to block the supply of the first current to the internal heater when there is no pulse.

[0307] The control circuit may be configured to control the temperature of the internal heater components by adjusting the pulses during each ON period. For example, the control circuit may be configured to control the temperature of the internal heater components by using pulse width modulation. The control circuit may be configured to control the temperature of the internal heater components by adjusting one or more of the duration of each pulse, the number of each pulse, or the time gap between adjacent pulses during each ON period. For example, the control circuit may be configured to maintain the temperature of the internal heater components at the internal heater target temperature or to follow the internal heater target temperature profile by adjusting the pulses during each ON period.

[0308] The pulse may occupy a proportion of each on-period. For example, the pulse may occupy 100% of each on-period so that a primary current is supplied to the internal heater for the entire duration of each on-period. Alternatively, the pulse may occupy 50% of each on-period so that a primary current is supplied to the internal heater for half the duration of each on-period. The control circuit may be configured to control the temperature of the internal heater components by adjusting the proportion of each on-period occupied by the pulse. For example, the control circuit may be configured to maintain the temperature of the internal heater components at or follow an internal heater target temperature profile by adjusting the proportion of each on-period occupied by the pulse.

[0309] The ON period may be 3000 milliseconds to 1 millisecond. The ON period may be 500 milliseconds to 1 millisecond. Preferably, the ON period is 100 milliseconds to 5 milliseconds. More preferably, the ON period is 50 milliseconds to 10 milliseconds. Even more preferably, the ON period is about 20 milliseconds.

[0310] The off-period may have a length of 3000 milliseconds to 1 millisecond. The off-period may have a length of 500 milliseconds to 1 millisecond. Preferably, the off-period has a length of 200 milliseconds to 10 milliseconds. More preferably, the off-period has a length of 100 milliseconds to 50 milliseconds. Even more preferably, the off-period has a length of approximately 70 milliseconds.

[0311] The control circuit may be configured to supply a second current to the external heater during the off period. In particular, the control circuit may be configured to supply a second current to the external heater only during the off period.

[0312] The temperature of the external heater components may be controlled by adjusting the length of the off period. For example, the control circuit may be configured to adjust the length of the off period to maintain the temperature of the external heater components at the external heater target temperature or to follow the external heater target temperature profile.

[0313] The control circuit may be configured to supply a second current to the external heater in one or more pulses during each off period. The pulses may consist of multiple separate pulses. The control circuit may be configured to block the supply of the second current to the external heater when there are no pulses.

[0314] The control circuit may be configured to control the temperature of the external heater components by adjusting the pulses during each off period. For example, the control circuit may be configured to control the temperature of the external heater components by using pulse width modulation. The control circuit may be configured to control the temperature of the external heater components by adjusting one or more of the duration of each pulse, the number of each pulse, or the time gap between adjacent pulses during each off period. For example, the control circuit may be configured to maintain the temperature of the external heater components at the external heater target temperature or to follow the external heater target temperature profile by adjusting the pulses during each off period.

[0315] The pulse may occupy a proportion of each off period. For example, the pulse may occupy 100% of each off period so that a second current is supplied to the external heater for the entire duration of each off period. Alternatively, the pulse may occupy 50% of each off period so that a second current is supplied to the external heater for half the duration of each off period. The control circuit may be configured to control the temperature of the external heater components by adjusting the proportion of each off period occupied by the pulse. For example, the control circuit may be configured to maintain the temperature of the external heater components at an external heater target temperature or to follow an external heater target temperature profile by adjusting the proportion of each off period occupied by the pulse.

[0316] The control circuit may be configured to supply a second current to the external heater over reduced time periods. Each reduced time period may be shorter than each off period. The control circuit may be configured to control the temperature of the external heater components by adjusting the length of the reduced time periods. Advantageously, by supplying a second current to the external heater over reduced time periods shorter than the off periods during off periods, the control circuit can avoid any overlap between the first current supplied to the internal heater and the second current supplied to the external heater.

[0317] Because the first current supplied from the power supply cannot instantaneously drop to zero when the first current supplied to the internal heater is stopped, the inclusion of a time gap between the reduced time period and the period during which the first current is supplied to the internal heater is advantageous in that it can be ensured that simultaneous supply of the first and second currents to the internal and external heaters, respectively, does not occur, i.e., simultaneous supply that could adversely affect the power supply, such as shortening the operating life of the power supply.

[0318] Furthermore, advantageously, the temperature of the external heater components may be controlled by adjusting the length of the reduced time period. For example, the control circuit may be configured to maintain the temperature of the external heater components at the external heater target temperature or to follow the external heater target temperature profile by adjusting the length of the reduced time period. The temperature of the external heater components may also be controlled by adjusting the length of the time gap between the reduced time period and the on period. For example, the control circuit may be configured to maintain the temperature of the external heater components at the external heater target temperature or to follow the external heater target temperature profile by adjusting the length of the time gap between the reduced time period and the on period. This allows the control circuit to use pulse width modulation to maintain the temperature of the external heater components at the external heater target temperature or to follow the external heater target temperature profile.

[0319] The controller may be configured to perform a calibration process before alternating between on and off periods. The controller may also be configured to perform a calibration process immediately after the aerosol generator is switched on. In particular, the controller may be configured to perform a calibration process before supplying a second current to the external heater.

[0320] The control circuit may be configured to maintain the temperature of the internal heater components at the internal heater target temperature or to follow the internal heater target temperature profile by adjusting the first current supplied to the internal heater. For example, the control circuit may be configured to maintain the temperature of the internal heater components at the internal heater target temperature or to follow the internal heater target temperature profile by adjusting the amplitude of the first current supplied to the internal heater.

[0321] The control circuit may be configured to maintain the temperature of the components of the external heater at the external heater target temperature or to follow the external heater target temperature profile by adjusting the second current supplied to the external heater. For example, the control circuit may be configured to maintain the temperature of the components of the external heater at the external heater target temperature or to follow the external heater target temperature profile by adjusting the amplitude of the second current supplied to the external heater.

[0322] At least a portion of the internal heater may surround the chamber at least partially. Advantageously, this can result in efficient heating of the aerosol-generating article by the internal heater. At least a portion of the internal heater may surround the chamber.

[0323] The external heater may surround the chamber at least partially. Advantageously, this can lead to efficient heating of the periphery of the aerosol-forming substrate by the external heater.

[0324] The inductor element and the resistive heating element may surround the same longitudinal portion of the chamber.

[0325] The external heater may be configured to heat the periphery of the chamber. Advantageously, if the internal heater is configured to heat the central portion of the aerosol-forming substrate, this arrangement can ensure that no portion of the aerosol-forming substrate is overheated.

[0326] The external heater may extend from the first end of the chamber to the second end of the chamber.

[0327] The aerosol generator may further include a jacket, which may at least partially define the chamber.

[0328] The external heater may be positioned on the outer surface of the jacket. The external heater may be wound around the outer surface of the jacket. Advantageously, the external heater does not come into contact with the outer surface of the aerosol-forming article when the aerosol-forming article is received into the chamber. This can protect the external heater from damage when the aerosol-forming article is inserted into the chamber, and can reduce the possibility of the aerosol-forming article overheating when a second current is supplied to the external heater.

[0329] At least a portion of the internal heater may be positioned on the outer surface of the jacket. At least a portion of the internal heater may be wound around the outer surface of the jacket. Advantageously, the portion of the internal heater does not come into contact with the outer surface of the aerosol-forming article when the aerosol-forming article is received into the chamber. This protects the portion of the internal heater from damage when the aerosol-forming article is inserted into the chamber.

[0330] The jacket may be a thermally conductive jacket. The thermal conductivity of the thermally conductive jacket shall be at least 20 Wm². -1 K -1 Preferably at least 30Wm -1 K -1 More preferably, at least 40 Wm -1 K -1 More preferably, about 80 Wm -1 K -1 Alternatively, this may be the case. Advantageously, the thermally conductive jacket ensures that heat is efficiently transferred from the resistance heating element to the aerosol-forming substrate.

[0331] The jacket may contain an electrical insulating material. The jacket may consist of an electrical insulating material. The jacket may contain a material having a relative permeability of 0.9 to 1.1, preferably 0.99 to 1.01. Therefore, the jacket may contain a material that is substantially transparent to the alternating magnetic field. Advantageously, the jacket may not substantially affect the alternating magnetic field induced in the chamber by the inductor element.

[0332] The jacket may contain ceramics. The ceramic may contain alumina. Advantageously, it has been found that alumina has suitable thermal properties to ensure efficient heat transfer from the resistance heating element to the aerosol-forming substrate. The ceramic may contain aluminum nitrate. Advantageously, it has been found that aluminum nitrate has suitable thermal properties to ensure efficient heat transfer from the resistance heating element to the aerosol-forming substrate.

[0333] The jacket may have a circular cross-section. The jacket may also have a substantially cylindrical shape. Therefore, advantageously, a cylindrical aerosol-forming article can be easily inserted into the chamber by the user in any orientation within 360 degrees.

[0334] The aerosol generator may further include a housing. The housing may at least partially enclose the chamber. The jacket may be housed within the housing.

[0335] A portion of the internal heater may be located within the housing. The portion of the internal heater may be located within the housing such that it at least partially encloses the jacket and the external heater. Therefore, advantageously, the jacket and external heater may be manufactured together as an external heater assembly, which may be insertable into the housing during manufacturing. This allows for a degree of modularity during manufacturing, in that different external heater assemblies can be inserted into different housings with different internal heater components. Furthermore, the external heater assembly may be interchangeable with respect to the housing containing the internal heater components.

[0336] The jacket may include a longitudinal axis. The jacket may include an inner surface. The inner surface may define a chamber. The jacket may include at least one groove defined on the inner surface of the jacket. At least one groove may extend parallel to the longitudinal axis.

[0337] An airflow channel may be defined between the aerosol-generating article and the jacket when the aerosol-generating article is received into the chamber. The airflow channel may extend from the distal end of the jacket to the proximal end of the jacket.

[0338] The airflow channel may be defined between the aerosol-generating article and at least one groove.

[0339] The airflow path may be defined from the distal end of the jacket through the airflow channel to the proximal end of the jacket when the aerosol-generating article is received into the chamber, or from the proximal end of the aerosol-generating article through the article to the distal end of the aerosol-generating article. Advantageously, this may provide a clear airflow path solution that does not require an airflow inlet defined through the housing.

[0340] The external heater may be wound around a winding axis that coincides with the longitudinal axis of the jacket. A portion of the internal heater may be wound around a winding axis that coincides with the longitudinal axis of the jacket.

[0341] In the sixth embodiment, the internal heater may include an inductor element, and the external heater may include a resistive heating element. The inductor element may be positioned adjacent to the chamber. The inductor element may be configured to generate an alternating magnetic field within the chamber when an alternating current is supplied. The resistive heating element may be positioned adjacent to the chamber. The resistive heating element may be configured to be resistively heated when a direct current is supplied.

[0342] The first current may be an alternating current. The alternating current may have a first frequency. The control circuit may be configured so that a second current is not supplied to the inductor element. The control circuit may be configured so that a direct current is not supplied to the inductor element. The control circuit may be configured so that only the first current is supplied to the inductor element. Advantageously, this may result in minimal resistive heating of the inductor element, thereby reducing the risk of overheating or burning of the peripheral portion of the aerosol-forming substrate.

[0343] When the first current is supplied, the inductor element may generate an alternating magnetic field within the chamber, thereby inductively heating one or more susceptors within the aerosol-generating article when the article is received into the chamber. Therefore, advantageously, the aerosol-forming substrate within the aerosol-generating article can be efficiently heated from both the outside and the inside.

[0344] An aerosol-forming article may comprise one or more susceptors. Each of the susceptors may be in the form of at least one strip, or at least one rod, or at least one particle. Advantageously, the structure of an aerosol generator can be simplified because the aerosol generator does not need to include susceptor elements. Each of the susceptors may be in the form of elongated particles. The elongated particles may be aligned along the long axis of the aerosol-forming article. The elongated particles may also be aligned along the long axis of the aerosol-forming substrate. Each of the susceptors may be in the form of one or more strips made of susceptor material. An aerosol-forming article may comprise one or more strips of an aerosol-forming substrate laminated with one or more strips made of susceptor material. For example, an aerosol-forming article may comprise one or more strips of tobacco material laminated with one or more strips made of susceptor material.

[0345] The aerosol generator may comprise one or more susceptors. Each of the susceptors may be in the form of at least one blade or at least one pin. Advantageously, each of the susceptors may be reused with multiple aerosol-forming articles. Each of the susceptors may be configured to be inserted into the aerosol-generating substrate when the aerosol-generating article is received into the chamber. Advantageously, this may allow for a simpler and more sustainable configuration when using the aerosol-forming article.

[0346] The second current may be a direct current. The control circuit may be configured such that the first current is not supplied to the resistive heating element. The control circuit may be configured such that no alternating current is supplied to the resistive heating element. The control circuit may be configured so that only the second current is supplied to the resistive heating element. Advantageously, this may mean that the resistive heating element does not have a magnetic interaction with the inductor element.

[0347] The control circuit may be configured to supply a second current to the resistive heating element so that the resistive heating element is heated to at least 80°C. Advantageously, heating the resistive heating element to at least 80°C may ensure that the resistive heating element adequately heats the aerosol-forming substrate so that vapor can be generated. The control circuit may be configured to supply a second current to the resistive heating element so that the resistive heating element is heated not to exceed 210°C. Advantageously, heating the resistive heating element not to exceed 210°C may ensure that the resistive heating element does not burn or char the aerosol-forming substrate, thereby ensuring that an aerosol is not generated that produces undesirable compounds and gives the user a burnt taste.

[0348] When an alternating magnetic field is generated by supplying an alternating current to an inductor element, the alternating magnetic field may induce an alternating current in the resistive heating element. Therefore, when a second current is supplied to the resistive heating element and the first current is supplied to the inductor element at the same time, the alternating current induced in the resistive heating element may affect the resistive heating feedback signal provided to the control circuit. For example, the alternating current induced in the resistive heating element may modify the resistive heating feedback signal provided to the control circuit. This may affect the control circuit's ability to accurately determine the temperature of the resistive heating element, and therefore its ability to maintain the temperature of the resistive heating element at or to follow the external heater target temperature profile.

[0349] Advantageously, if the control circuit is configured to block the supply of a second current to the resistive heating element when a first current is supplied to the inductor element, the induced AC current does not affect the resistive heating feedback signal. Therefore, the control circuit can determine the temperature of the resistive heating element more accurately.

[0350] Similarly, the control circuit may be configured to prevent the supply of the first current to the inductor element when the second current is being supplied to the resistive heating element. The control circuit may also be configured to prevent the simultaneous supply of the first current to the inductor element and the second current to the resistive heating element.

[0351] When an alternating magnetic field is generated in the chamber by an alternating current in an inductor coil, depending on the configuration of adjacent resistive heating elements, the alternating magnetic field may induce an alternating current in the adjacent resistive heating elements. The resistive heating elements may be configured such that the total current induced in them by the alternating magnetic field is substantially zero.

[0352] The resistive heating element may include at least one primary portion. The resistive heating element may include at least one secondary portion. The resistive heating element may be configured such that the current induced in at least one primary portion by the alternating magnetic field is approximately equal to and opposite to the current induced in at least one secondary portion by the alternating magnetic field.

[0353] The resistive heating element may form an electrical path from the positive terminal to the negative terminal of the control circuit. At least one primary portion may extend along the electrical path clockwise around the chamber toward the negative terminal of the control circuit when viewed from the first end of the chamber.

[0354] The second current can be considered to flow from the positive terminal of the control circuit to the negative terminal of the control circuit. At least one primary section may be arranged such that, when viewed from the first end of the chamber, the second current flows clockwise around the chamber within at least one primary section.

[0355] At least one secondary portion may extend along the electrical path toward the negative terminal of the control circuit in the opposite direction to at least one primary portion when viewed from the first end of the chamber. For example, at least one secondary portion may extend along the electrical path toward the negative terminal of the control circuit in a counterclockwise direction when viewed from the first end of the chamber.

[0356] At least one secondary section may be configured such that, when viewed from the first end of the chamber, the second current flows in the at least one secondary section in the opposite direction to the second current in the at least one primary section. For example, at least one secondary section may be configured such that, when viewed from the first end of the chamber, the second current flows in the at least one secondary section in a counterclockwise direction around the chamber.

[0357] The cumulative length of at least one primary part may be substantially equal to the cumulative length of at least one secondary part.

[0358] The alternating current induced within a resistive heating element can be particularly disadvantageous because the control circuit requires a filter to ensure that the alternating current induced within the resistive heating element does not damage any electronic components electrically connected to it. Advantageously, in the above configuration, the resistive heating element is positioned such that any alternating current induced within the resistive heating element toward the negative terminal of the control circuit is equal to the current induced within the resistive heating element toward the positive terminal of the control circuit. As a result, the total alternating current induced within the resistive heating element between the positive and negative terminals of the control circuit is at least significantly reduced, to approximately zero. This minimization of the total alternating current induced within the resistive heating element between the positive and negative terminals of the control circuit means that a filter is not required to ensure that the alternating current induced within the resistive heating element does not damage any electronic components electrically connected to it. Therefore, the complexity of the control circuit can be significantly reduced.

[0359] At least one primary part may be formed integrally with at least one secondary part.

[0360] The resistance heating element may include exactly one primary portion. The resistance heating element may include exactly one secondary portion. The primary and secondary portions may extend from the portion adjacent to the first end of the chamber to the portion adjacent to the second end of the chamber.

[0361] The primary and secondary sections may be electrically connected to the power supply at the second end of the chamber. The first end of the primary section may be electrically connected to the positive terminal of the control circuit. The first end of the secondary section may be electrically connected to the negative terminal of the control circuit.

[0362] The primary and secondary sections may be directly connected to each other adjacent to the first end of the chamber. In particular, the second end of the primary section, located opposite the first end of the primary section, may be directly connected to the second end of the secondary section, located opposite the first end of the secondary section.

[0363] The primary part may be formed integrally with the secondary part.

[0364] The primary and secondary parts may be wound together around the chamber such that they are substantially parallel to each other. The primary and secondary parts may be wound together in a helical manner around the chamber.

[0365] Advantageously, this arrangement allows for a clear implementation of the above concept and provides two co-wound sections such that the total induced AC current between the positive and negative terminals of the control circuit is at least significantly reduced to approximately zero.

[0366] The resistance heating element may be arranged in a meandering shape. The resistance heating element may include two filaments arranged in a meandering shape such that the two filaments are substantially parallel to each other. In this arrangement, the resistance heating element may include a plurality of alternating primary and secondary parts, as described above.

[0367] Advantageously, this arrangement makes it possible to implement the above concept that the total induced AC current within the serpentine resistance heating element between the positive and negative terminals of the control circuit is at least significantly reduced to approximately zero.

[0368] The resistance heating element may be folded or curved to at least partially enclose the chamber. Therefore, advantageously, the resistance heating element may be printed onto a substantially flat and planar substrate before being folded or curved to at least partially enclose the chamber. This may provide a simple and reliable method for manufacturing an aerosol generator. For example, the resistance heating element may be printed onto a substantially flat and planar polyimide substrate.

[0369] The inductor element may be an inductor coil. The inductor coil may be a helical coil. The resistive heating element may be a resistive heating coil. The resistive heating coil may be a helical coil. The resistive heating coil and the inductor coil may be wound together. Advantageously, this can result in a space-efficient arrangement in which the two separate heating systems can be positioned adjacent to the aerosol-forming substrate when the aerosol-forming article is received in the chamber.

[0370] The resistance heating coil may be wound around a winding axis. The inductor coil may be wound around the same winding axis as the resistance heating coil.

[0371] The inductor element may include a first filament. The first filament may include a first cross-sectional area.

[0372] The first cross-sectional area may be defined by a first plane. The first cross-sectional area may be perpendicular to the direction of extension of the first filament. The first cross-sectional area may be perpendicular to the direction of extension of the first filament between the first and second ends of the inductor element. The orthogonality with respect to the first plane defining the first cross-sectional area may be perpendicular to the winding axis. The first cross-sectional area may be substantially constant between the first and second ends of the inductor element. Advantageously, this arrangement can be ensured that no portion of the inductor element between the first and second ends generates more heat via resistive heating than any other portion.

[0373] The first cross-sectional area may be perpendicular to the first current flow direction. The first cross-sectional area may be substantially rectangular in shape. Advantageously, it has been found that a rectangular cross-section increases the efficiency of the inductor element and reduces capacitance losses within the inductor element. Furthermore, the size of the aerosol generator can therefore be reduced by using a rectangular cross-section with respect to the inductor element. The first cross-sectional area may have a first width and a first thickness. The first width may be greater than the first thickness. The first width may be at least five times greater than the first thickness. For example, the first width may be at least ten times greater than the first thickness. Preferably, the first width may be at least fifteen times greater than the first thickness. The first width may be 0.1 mm to 5 mm. For example, the first width may be 0.5 mm to 4 mm. Preferably, the first width is 1 mm to 3 mm. The first thickness may be 0.02 mm to 1 mm. The first thickness may be 0.05 mm to 0.5 mm. The first thickness is preferably 0.05 mm to 0.2 mm. The first width may be parallel to the longitudinal axis of the jacket. The first width may be parallel to the winding axis of the inductor coil. The first thickness may be perpendicular to the longitudinal axis of the jacket. The first thickness may be perpendicular to the winding axis of the inductor coil. Advantageously, it has been found that this shape of the inductor element and these dimensions provide minimal heating of the inductor element via resistive heating, and also provide strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0374] The resistance heating element may include a second filament. The second filament may include a second cross-sectional area. The second cross-sectional area may be defined by the first plane. The second cross-sectional area may be defined by the same plane as the first cross-sectional area. The second cross-sectional area may be perpendicular to the direction of extension of the second filament. The second cross-sectional area may be perpendicular to the direction of extension of the second filament between the first and second ends of the resistance heating element. The orthogonality of the first plane defining the second cross-sectional area may be perpendicular to the winding axis. The second cross-sectional area may be substantially constant between the first and second ends of the resistance heating element. The first cross-sectional area may be larger than the second cross-sectional area. The first cross-sectional area may be at least five times larger than the second cross-sectional area. For example, the first cross-sectional area may be at least ten times larger than the second cross-sectional area. Preferably, the first cross-sectional area is at least fifteen times larger than the second cross-sectional area. It is even more preferable that the first cross-sectional area is at least 20 times larger than the second cross-sectional area. Advantageously, a larger ratio of the first cross-sectional area to the second cross-sectional area means that resistive heating within the inductor element is reduced, and that the majority of the resistive heating occurs within the resistive heating body as intended.

[0375] The second cross-sectional area may be perpendicular to the direction of the second current flow. The second cross-sectional area may be substantially circular in shape. The second cross-sectional area may have a diameter of 0.1 to 0.4 millimeters. Advantageously, it has been found that this shape and these dimensions of the resistance heating element allow for proper heating of the resistance heating element by resistance heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0376] The second cross-sectional area is preferably substantially rectangular in shape. Advantageously, it has been found that the rectangular cross-section enhances the efficiency of the resistance heating element by providing a larger contact area with the periphery of the aerosol-forming substrate or jacket. The second cross-sectional area may have a second width and a second thickness. The second width may be greater than the second thickness. The second width may be at least 5 times greater than the second thickness. For example, the second width may be at least 10 times greater than the second thickness. Preferably, the second width is at least 25 times greater than the second thickness. The second width may be 0.1 mm to 5 mm. For example, the second width may be 0.2 mm to 2 mm. Preferably, the second width is 0.5 mm to 0.7 mm. The second thickness may be 0.005 mm to 0.5 mm. The second thickness may be 0.01 mm to 0.1 mm. Preferably, the second thickness is 0.02 mm to 0.05 mm. The second width may be parallel to the longitudinal axis of the jacket. The second width may be parallel to the winding axis of the inductor coil. The second thickness may be perpendicular to the longitudinal axis of the jacket. The second thickness may be perpendicular to the winding axis of the inductor coil. Advantageously, it has been found that this shape and these dimensions of the resistance heating element provide efficient resistance heating of the periphery of the aerosol-forming substrate.

[0377] The inductor element may contain a metal. The inductor element may contain copper. The inductor element may be made of copper. Advantageously, it has been found that copper provides minimal heating of the inductor element via resistive heating, and also provides a strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0378] The resistance heating element may contain a metal. The resistance heating element may contain stainless steel. The resistance heating element may be made of stainless steel. Advantageously, stainless steel has been found to be a durable material with a suitable resistivity for maximizing the heating of the resistance heating element by resistance heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the resistance heating element.

[0379] The inductor element may contain materials different from those of the resistive heating element. The inductor element may be made of materials different from those of the resistive heating element.

[0380] In a further embodiment of the sixth aspect, the internal heater may include an internal resistive heating element, and the external heater may include an external resistive heating element.

[0381] The internal resistance heating element may be placed inside the chamber. The internal resistance heating element may include at least one pin configured to be inserted into the aerosol generating substrate when the aerosol generating article is received inside the chamber. The internal resistance heating element may include at least one blade configured to be inserted into the aerosol generating substrate when the aerosol generating article is received inside the chamber. The internal resistance heating element may be configured to be resistively heated when a direct current is supplied.

[0382] The external resistance heating element may be positioned adjacent to the chamber. The external resistance heating element may be configured to resistively heat when a DC current is supplied. The external resistance heating element may be folded or curved to at least partially enclose the chamber. Advantageously, the external resistance heating element may be printed onto a substantially flat and planar substrate before being folded or curved to at least partially enclose the chamber. This may provide a simple and reliable method for manufacturing an aerosol generator. For example, the external resistance heating element may be printed onto a substantially flat and planar polyimide substrate.

[0383] The external resistance heating element may be wound around a winding axis. The external resistance heating element may include a filament. The filament may include a cross-sectional area. The cross-sectional area may be defined by a first plane. The cross-sectional area may be perpendicular to the direction of extension of the filament. The cross-sectional area may be perpendicular to the direction of extension of the filament between the first and second ends of the external resistance heating element. The orthogonality with respect to the first plane defining the cross-sectional area may be perpendicular to the winding axis. The cross-sectional area may be substantially constant between the first and second ends of the resistance heating element.

[0384] The cross-sectional area may be perpendicular to the direction of the second current flow. The cross-sectional area may be substantially circular in shape. The cross-sectional area may have a diameter of 0.1 to 0.4 millimeters. Advantageously, it has been found that this shape and these dimensions of the external resistance heating element allow for proper heating of the external resistance heating element by resistance heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the external resistance heating element.

[0385] The cross-sectional area is preferably substantially rectangular in shape. Advantageously, it has been found that a rectangular cross-section enhances the efficiency of the external resistance heating element by providing a larger contact area with the aerosol-forming substrate or the periphery of the jacket. The cross-sectional area may have width and thickness. The width may be greater than the thickness. The width may be at least 5 times greater than the thickness. For example, the width may be at least 10 times greater than the thickness. Preferably, the width is at least 25 times greater than the thickness. The width may be 0.1 mm to 5 mm. For example, the width may be 0.2 mm to 2 mm. Preferably, the width is 0.5 mm to 0.7 mm. The thickness may be 0.005 mm to 0.5 mm. The thickness may be 0.01 mm to 0.1 mm. Preferably, the thickness is 0.02 mm to 0.05 mm. The width may be parallel to the longitudinal axis of the jacket. The thickness may be perpendicular to the longitudinal axis of the jacket. Advantageously, it was found that this shape and these dimensions of the external resistance heating element provide efficient resistance heating of the periphery of the aerosol-forming substrate.

[0386] In this further embodiment, the first current may be a direct current. The control circuit may be configured so that a second current is not supplied to the internal resistance heating element. The control circuit may be configured so that only the first current is supplied to the internal resistance heating element.

[0387] In this further embodiment, the second current may also be a DC current. The control circuit may be configured such that the first current is not supplied to the external resistive heating element. The control circuit may be configured such that only the second current is supplied to the external resistive heating element.

[0388] Advantageously, this may also mean that, when the first and second currents are supplied in an alternating manner, power is supplied from the power source to only one of the internal resistance heating element or the external resistance heating element at a time. As described above, this can advantageously ensure that the power source is utilized optimally and efficiently.

[0389] The control circuit may be configured to provide a second current to the external resistive heating element and a first current to the internal resistive heating element so that the external resistive heating element and the internal resistive heating element are heated to at least 80°C. Advantageously, heating the external resistive heating element and the internal resistive heating element to at least 80°C may ensure that the external resistive heating element and the internal resistive heating element adequately heat the aerosol-forming substrate so that vapor can be generated. The control circuit may be configured to provide a second current to the external resistive heating element and a first current to the internal resistive heating element so that the external resistive heating element and the internal resistive heating element are heated not to exceed 210°C. Advantageously, by heating the external and internal resistance heating elements so as not to exceed 210°C, it can be assured that the external and internal resistance heating elements will not burn or char the aerosol-forming substrate, and thereby it can be assured that aerosols that produce undesirable compounds and cause the user to perceive a burnt taste will not be generated.

[0390] The external resistance heating element may contain metal. The external resistance heating element may contain stainless steel. The external resistance heating element may be made of stainless steel. Advantageously, stainless steel has been found to be a durable material with a suitable resistivity for maximizing the heating of the external resistance heating element by resistance heating. This results in more efficient heating of the periphery of the aerosol-forming substrate by the external resistance heating element.

[0391] The internal resistance heating element may contain metal. The internal resistance heating element may contain stainless steel. The internal resistance heating element may be made of stainless steel. Advantageously, stainless steel has been found to be a durable material with a suitable resistivity for maximizing the heating of the internal resistance heating element by resistance heating. This results in more efficient heating of the internal portion of the aerosol-forming substrate by the internal resistance heating element.

[0392] In a further embodiment of the sixth aspect, the internal heater may include an internal resistance heating element, and the external heater may include an external induction heating element.

[0393] The internal resistance heating element may be placed inside the chamber. The internal resistance heating element may include at least one pin configured to be inserted into the aerosol generating substrate when the aerosol generating article is received inside the chamber. The internal resistance heating element may include at least one blade configured to be inserted into the aerosol generating substrate when the aerosol generating article is received inside the chamber. The internal resistance heating element may be configured to be resistively heated when a direct current is supplied.

[0394] In this further embodiment, the first current may be a direct current. The control circuit may be configured so that a second current is not supplied to the internal resistance heating element. The control circuit may be configured so that only the first current is supplied to the internal resistance heating element.

[0395] In this further embodiment, the second current may be an alternating current. The control circuit may be configured such that the first current is not supplied to the external induction heating element. The control circuit may be configured such that only the second current is supplied to the external induction heating element.

[0396] Advantageously, this may also mean that, when the first and second currents are supplied in an alternating manner, power is supplied from the power source to only one of the internal resistance heating element or the external induction heating element at a time. As described above, this can advantageously ensure that the power source is utilized optimally and efficiently.

[0397] The external induction heating element may be positioned adjacent to the chamber. The external induction heating element may comprise an inductor element and a susceptor element. The susceptor element may comprise a susceptor sleeve positioned adjacent to the chamber. The susceptor element may at least partially enclose the chamber. The susceptor element may at least partially enclose the jacket. The susceptor element may be located on the outer surface of the jacket.

[0398] The inductor element may include an inductor coil. The inductor coil may be a helical coil. The inductor element may at least partially surround the susceptor element. The inductor element may be configured to generate an alternating magnetic field within the region of the susceptor element when an alternating current is supplied. The alternating magnetic field may be configured to heat the susceptor element.

[0399] Therefore, advantageously, the aerosol-forming substrate within the aerosol-generating article can be efficiently heated from both the outside and the inside.

[0400] The second current may be an alternating current. The alternating current may have a first frequency. The control circuit may be configured so that the first current is not supplied to the inductor element. The control circuit may be configured so that a direct current is not supplied to the inductor element. The control circuit may be configured so that only the second current is supplied to the inductor element. Advantageously, this may result in minimal resistive heating of the inductor element, thereby reducing the risk of undesirable heating of any part of the aerosol generator housing.

[0401] The inductor element may include a first filament. The first filament may include a first cross-sectional area. The first cross-sectional area may be defined by a first plane. The first cross-sectional area may be perpendicular to the direction of extension of the first filament. The first cross-sectional area may be perpendicular to the direction of extension of the first filament between the first and second ends of the inductor element. The orthogonality with respect to the first plane defining the first cross-sectional area may be perpendicular to the winding axis. The first cross-sectional area may be substantially constant between the first and second ends of the inductor element. Advantageously, this arrangement can be ensured that no portion of the inductor element between the first and second ends generates more heat via resistive heating than any other portion.

[0402] The first cross-sectional area may be perpendicular to the second current flow direction. The first cross-sectional area may be substantially rectangular in shape. Advantageously, it has been found that a rectangular cross-section increases the efficiency of the inductor element and reduces capacitance losses within the inductor element. Furthermore, the size of the aerosol generator can therefore be reduced by using a rectangular cross-section with respect to the inductor element. The first cross-sectional area may have a first width and a first thickness. The first width may be greater than the first thickness. The first width may be at least five times greater than the first thickness. For example, the first width may be at least ten times greater than the first thickness. Preferably, the first width may be at least fifteen times greater than the first thickness. The first width may be 0.1 mm to 5 mm. For example, the first width may be 0.5 mm to 4 mm. Preferably, the first width is 1 mm to 3 mm. The first thickness may be 0.02 mm to 1 mm. The first thickness may be 0.05 mm to 0.5 mm. The first thickness is preferably 0.05 mm to 0.2 mm. The first width may be parallel to the longitudinal axis of the jacket. The first width may be parallel to the winding axis of the inductor coil. The first thickness may be perpendicular to the longitudinal axis of the jacket. The first thickness may be perpendicular to the winding axis of the inductor coil. Advantageously, it has been found that this shape of the inductor element and these dimensions provide minimal heating of the inductor element via resistive heating, and also provide strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0403] The control circuit may be configured to supply a first current to the internal resistance heating element so that the internal resistance heating element is heated to at least 80°C. Advantageously, heating the internal resistance heating element to at least 80°C may ensure that the internal resistance heating element adequately heats the aerosol-forming substrate so that vapor can be generated. The control circuit may be configured to supply a first current to the internal resistance heating element so that the internal resistance heating element is heated not to exceed 210°C. Advantageously, heating the internal resistance heating element not to exceed 210°C may ensure that the internal resistance heating element does not burn or char the aerosol-forming substrate, thereby ensuring that an aerosol is not generated that produces undesirable compounds and gives the user a burnt taste.

[0404] The inductor element may contain a metal. The inductor element may contain copper. The inductor element may be made of copper. Advantageously, it has been found that copper provides minimal heating of the inductor element via resistive heating, and also provides a strong coupling between the susceptor element and the inductor element. This results in more efficient heating of the susceptor element by the inductor element.

[0405] The internal resistance heating element may contain metal. The internal resistance heating element may contain stainless steel. The internal resistance heating element may be made of stainless steel. Advantageously, stainless steel has been found to be a durable material with a suitable resistivity for maximizing the heating of the internal resistance heating element by resistance heating. This results in more efficient heating of the internal portion of the aerosol-forming substrate by the internal resistance heating element.

[0406] According to a seventh aspect of the present disclosure, an aerosol generating system is also provided, which comprises an aerosol generating device according to a sixth aspect of the present disclosure and an aerosol generating article having an aerosol generating substrate, the aerosol generating article being housed in a chamber of the aerosol generating device. The aerosol generating article may comprise any aerosol generating article according to a fourth aspect of the present disclosure.

[0407] According to the eighth aspect of this disclosure, a method is provided for generating an aerosol by controlling an aerosol generating system, the system being: an aerosol generating article containing an aerosol-forming substrate, an aerosol generator comprising an aerosol generator having a chamber for receiving at least a portion of an aerosol generating article, The aerosol generator is Internal heater, External heater and, At least one power supply for providing power to the internal heater and the external heater, The system further comprises a control circuit configured to control the power supply from at least one power source to an internal heater and to an external heater, The method is, A step of supplying power to an internal heater so that the internal heater heats the aerosol-forming substrate from an internal position within the aerosol-forming substrate, A step of supplying power to an external heater so that the external heater heats the aerosol-forming substrate from an external position outside the aerosol-forming substrate, The process includes a step of blocking the power supply to one of the external heater and the internal heater when power is being supplied to the other of the external heater and the internal heater.

[0408] Advantageously, by blocking the power supply to the external heater when power is being supplied to the internal heater, the aerosol generator can utilize the energy stored in at least one power source in a more efficient manner, which may allow the user to have a longer aerosol generation experience. Simultaneous power supply from a power source to two separate internal and external heaters has been found to be detrimental to the efficiency of at least one power source.

[0409] The aerosol generator may be any aerosol generator according to the sixth aspect of this disclosure.

[0410] Providing power to the internal heater may include providing a first current to the internal heater.

[0411] Providing power to an external heater may include providing a second current to the external heater.

[0412] The method may include blocking the power supply to the external heater when power is being supplied to the internal heater. The method may also include controlling the power supply to the external heater depending on the power profile supplied to the internal heater. For example, the method may include blocking the power supply to the external heater when power is being supplied to the internal heater, and not blocking the power supply to the external heater when power is not being supplied to the internal heater. In other words, the method may include allowing the power supply to the external heater when power is not being supplied to the internal heater.

[0413] The method may include blocking the power supply to the internal heater when power is being supplied to the external heater. The method may also include controlling the power supply to the internal heater depending on the power profile supplied to the external heater. For example, the method may include blocking the power supply to the internal heater when power is being supplied to the external heater, and not blocking the power supply to the internal heater when power is not being supplied to the external heater. In other words, the method may include allowing the power supply to the internal heater when power is not being supplied to the external heater.

[0414] The method may further include providing a first current to the internal heater and a second current to the external heater at different times.

[0415] For example, the method may further include supplying a first current to an internal heater and then supplying a second current to an external heater. The method may further include supplying a first current to an internal heater over a first time period. The method may further include supplying a second current to an external heater over a second time period following the first time period. Advantageously, the aerosol-forming substrate may be heterogeneous, and different parts of the aerosol-forming substrate may be heated at different times by heating the aerosol-forming substrate from the inside and then from the outside. Because the aerosol-forming substrate may be heterogeneous, aerosols having aerosol properties may be generated at different times.

[0416] The method may further include supplying a second current to an external heater, and then supplying a first current to an internal heater. The method may further include supplying a second current to an external heater over a first time period. The method may further include supplying a first current to an internal heater over a second time period following the first time period. Advantageously, the aerosol-forming substrate may be heterogeneous, and different parts of the aerosol-forming substrate may be heated at different times by heating the aerosol-forming substrate by resistance heating followed by induction heating. Because the aerosol-forming substrate may be heterogeneous, aerosols having aerosol properties may be generated at different times.

[0417] The method may further include detecting the time when a user is inhaling smoke on the system. For example, the control circuit may be coupled to a pressure sensor, and the method includes detecting a pressure drop when a user is inhaling smoke on the system. When the pressure sensor detects a pressure drop when a user is inhaling smoke on the system, the method may further include supplying power to an internal heater or an external heater, or to both an internal heater and an external heater. For example, the method may further include initiating a first time period in response to a user inhaling smoke on the system.

[0418] The control circuit may include a user-activatable trigger. For example, the user-activatable trigger may include a button or a switch. The method may further include initiating a first time period in response to the activation of the user-activatable trigger.

[0419] The method is, The system has performed a predetermined number of smoke inhalations, or A predetermined amount of time has elapsed since the first smoke extraction on the system, or A user-activated trigger has been activated, or This may further include ending the first time period and starting the second time period in response to any one or more of the above-mentioned combinations.

[0420] The method may further include providing a first current to an internal heater and a second current to an external heater in an alternating sequence. Advantageously, alternating internal and external heating may be beneficial in order to avoid overheating of any portion of the aerosol-forming substrate.

[0421] The control circuit may include a microcontroller. The method may further include receiving an internal heating feedback signal from an internal heater and receiving an external heating feedback signal from an external heater. The internal heating feedback signal may include at least one of voltage, current, or conductance. For example, the internal heating feedback signal may include voltage and current. The external heating feedback signal may include at least one of voltage, current, or conductance. For example, the external heating feedback signal may include voltage and current.

[0422] The method may further include providing a first current to an internal heater based on an internal heating feedback signal. The method may further include providing a second current to an external heater based on an external heating feedback signal. The internal heating feedback signal may depend on the temperature of the components of the internal heater. The external heating feedback signal may depend on the temperature of the components of the external heater.

[0423] The method may further include adjusting a first current supplied to the internal heater in accordance with an internal heating feedback signal. The method may further include determining the temperature of the internal heater components in accordance with the internal heating feedback signal. The method may further include maintaining the temperature of the internal heater components at an internal heater target temperature or following an internal heater target temperature profile by adjusting the first current supplied to the internal heater in accordance with the internal heating feedback signal.

[0424] The method may further include adjusting a second current supplied to the external heater in accordance with an external heating feedback signal. The method may further include determining the temperature of the external heater in accordance with the external heating feedback signal. The method may further include maintaining the temperature of the components of the external heater at an external heater target temperature or following an external heater target temperature profile by adjusting the second current supplied to the external heater in accordance with the external heating feedback signal.

[0425] The method may further include providing a first current to the internal heater during the ON period and preventing the first current from being provided to the internal heater during the OFF period. The method may further include providing a second current to the external heater during the OFF period and preventing the second current from being provided to the external heater during the ON period. The method may further include alternating between the ON and OFF periods.

[0426] The method may further include supplying a switching voltage to control circuit components in order to control a first current supplied to an internal heater. Specifically, in the embodiments described below in which the internal heater comprises an inductor element, the method may further include supplying a switching voltage to a DC / AC converter in order to control a first current supplied to the internal heater. In particular, the method may further include supplying a switching voltage to a field-effect transistor of the DC / AC converter in order to control a first current supplied to the internal heater.

[0427] The method may further include supplying a switching voltage to control circuit components to control a second current supplied to an external heater. Specifically, in the embodiments described below in which the external heater includes an inductor element, the method may further include supplying a switching voltage to a DC / AC converter to control a second current supplied to the external heater. In particular, the method may further include supplying a switching voltage to a field-effect transistor of the DC / AC converter to control a second current supplied to the external heater.

[0428] The switching voltage may have a rectangular profile.

[0429] The switching voltage may include alternating on periods in which a first current is supplied to the internal heater and off periods in which the supply of the first current to the internal heater is prevented. The control circuit may be configured to prevent the supply of a second current to the external heater during the on period.

[0430] The switching voltage may include alternating off periods in which a second current is supplied to the external heater and on periods in which the supply of the second current to the external heater is prevented. The control circuit may be configured to prevent the supply of the first current to the internal heater during the on periods.

[0431] Specifically, the method may further include supplying a switching voltage to a DC / AC converter to control a first current supplied to an internal heater. In particular, the method may further include supplying a switching voltage to a field-effect transistor of the DC / AC converter to control a first current supplied to an internal heater. The switching voltage may have a rectangular profile. The switching voltage may include alternating on periods in which a first current is supplied to the internal heater and off periods in which the supply of the first current to the internal heater is prevented.

[0432] The temperature of the internal heater components may be controlled by adjusting the length of the on-time. For example, the method may further include maintaining the temperature of the internal heater components at an internal heater target temperature or following an internal heater target temperature profile by adjusting the length of the on-time.

[0433] The method may further include supplying a first current to the internal heater in one or more pulses during each ON period. The pulses may include a plurality of separate pulses. The method may further include blocking the supply of the first current to the internal heater when not in pulse mode.

[0434] The method may further include controlling the temperature of the internal heater components by adjusting the pulses during each ON period. For example, the method may further include controlling the temperature of the internal heater components by using pulse width modulation. The method may further include controlling the temperature of the internal heater components by adjusting one or more of the duration of each pulse, the number of each pulse, or the time gap between adjacent pulses during each ON period. For example, the method may further include maintaining the temperature of the internal heater components at an internal heater target temperature or following an internal heater target temperature profile by adjusting the pulses during each ON period.

[0435] The pulse may occupy a proportion of each on-period. For example, the pulse may occupy 100% of each on-period so that a primary current is supplied to the internal heater for the entire duration of each on-period. Alternatively, the pulse may occupy 50% of each on-period so that a primary current is supplied to the internal heater for half the duration of each on-period. The method may further include controlling the temperature of the internal heater components by adjusting the proportion of each on-period occupied by the pulse. For example, the method may further include maintaining the temperature of the internal heater components at an internal heater target temperature or following an internal heater target temperature profile by adjusting the proportion of each on-period occupied by the pulse.

[0436] The ON period may be 3000 milliseconds to 1 millisecond. The ON period may be 500 milliseconds to 1 millisecond. Preferably, the ON period is 100 milliseconds to 5 milliseconds. More preferably, the ON period is 50 milliseconds to 10 milliseconds. Even more preferably, the ON period is about 20 milliseconds.

[0437] The off-period may have a length of 3000 milliseconds to 1 millisecond. The off-period may have a length of 500 milliseconds to 1 millisecond. Preferably, the off-period has a length of 200 milliseconds to 10 milliseconds. More preferably, the off-period has a length of 100 milliseconds to 50 milliseconds. Even more preferably, the off-period has a length of approximately 70 milliseconds.

[0438] The method may further include providing a second current to an external heater during the off period. In particular, the method may further include providing a second current to an external heater only during the off period.

[0439] The temperature of the external heater components may be controlled by adjusting the length of the off period. For example, the method may further include maintaining the temperature of the external heater components at the external heater target temperature or following the external heater target temperature profile by adjusting the length of the off period.

[0440] The method may further include supplying a second current to an external heater in one or more pulses during each off period. The pulses may include multiple separate pulses. The method may further include blocking the supply of the second current to the external heater when not in a pulse.

[0441] The method may further include controlling the temperature of the external heater components by adjusting the pulses during each off period. For example, the method may further include controlling the temperature of the external heater components by using pulse width modulation. The method may further include controlling the temperature of the external heater components by adjusting one or more of the duration of each pulse, the number of each pulse, or the time gap between adjacent pulses during each off period. For example, the method may further include maintaining the temperature of the external heater components at the external heater target temperature or following the external heater target temperature profile by adjusting the pulses during each off period.

[0442] The pulse may occupy a proportion of each off period. For example, the pulse may occupy 100% of each off period so that a second current is supplied to the external heater for the entire duration of each off period. Alternatively, the pulse may occupy 50% of each off period so that a second current is supplied to the external heater for half the duration of each off period. The method may further include controlling the temperature of the external heater components by adjusting the proportion of each off period occupied by the pulse. For example, the method may further include maintaining the temperature of the external heater components at an external heater target temperature or following an external heater target temperature profile by adjusting the proportion of each off period occupied by the pulse.

[0443] The method may further include supplying a second current to the external heater over reduced time periods, each of which may be shorter than each off period. The method may further include controlling the temperature of the external heater components by adjusting the length of the reduced time periods. Advantageously, by supplying a second current to the external heater over reduced time periods shorter than the off periods during off periods, the control circuit can avoid any overlap between the first current supplied to the internal heater and the second current supplied to the external heater.

[0444] Because the first current supplied from the power supply cannot instantaneously drop to zero when the first current supplied to the internal heater is stopped, the inclusion of a time gap between the reduced time period and the period during which the first current is supplied to the internal heater is advantageous in that it can be ensured that simultaneous supply of the first and second currents to the internal and external heaters, respectively, does not occur, i.e., simultaneous supply that could adversely affect the power supply, such as shortening the operating life of the power supply.

[0445] Furthermore, advantageously, the temperature of the external heater components may be controlled by adjusting the length of the reduced time period. For example, the method may further include maintaining the temperature of the external heater components at the external heater target temperature or following the external heater target temperature profile by adjusting the length of the reduced time period. The temperature of the external heater components may also be controlled by adjusting the length of the time gap between the reduced time period and the on period. For example, the method may further include maintaining the temperature of the external heater components at the external heater target temperature or following the external heater target temperature profile by adjusting the length of the time gap between the reduced time period and the on period. This allows the control circuit to use pulse width modulation to maintain the temperature of the external heater components at the external heater target temperature or follow the external heater target temperature profile.

[0446] The method may further include performing a calibration process before alternating between on and off periods. The method may further include performing a calibration process immediately after the aerosol generator is switched on. In particular, the method may further include performing a calibration process before supplying a second current to an external heater.

[0447] The method may further include adjusting a first current supplied to the internal heater to maintain the temperature of the internal heater components at an internal heater target temperature or to follow an internal heater target temperature profile. For example, the method may further include adjusting the amplitude of the first current supplied to the internal heater to maintain the temperature of the internal heater components at an internal heater target temperature or to follow an internal heater target temperature profile.

[0448] The method may further include adjusting a second current supplied to the external heater to maintain the temperature of the external heater components at the external heater target temperature or to follow the external heater target temperature profile. For example, the method may further include adjusting the amplitude of the second current supplied to the external heater to maintain the temperature of the external heater components at the external heater target temperature or to follow the external heater target temperature profile.

[0449] In the eighth embodiment, the internal heater may include an inductor element, and the external heater may include a resistive heating element. The inductor element may be positioned adjacent to the chamber. The inductor element may be configured to generate an alternating magnetic field within the chamber when an alternating current is supplied. The resistive heating element may be positioned adjacent to the chamber. The resistive heating element may be configured to be resistively heated when a direct current is supplied.

[0450] Providing power to the internal heater may include supplying alternating current to the inductor element. The alternating current may have a first frequency. The method may further include not supplying a second current to the inductor element. The method may further include not supplying a direct current to the inductor element. The method may further include supplying only the first current to the inductor element. Advantageously, this may result in minimal resistive heating of the inductor element, thereby reducing the risk of overheating or burning of the peripheral portion of the aerosol-forming substrate.

[0451] When the first current is supplied, the inductor element may generate an alternating magnetic field within the chamber, thereby inductively heating one or more susceptors within the aerosol-generating article when the article is received into the chamber. Therefore, advantageously, the aerosol-forming substrate within the aerosol-generating article can be efficiently heated from both the outside and the inside.

[0452] An aerosol-forming article may comprise one or more susceptors. Each of the susceptors may be in the form of at least one strip, or at least one rod, or at least one particle. Advantageously, the structure of an aerosol generator can be simplified because the aerosol generator does not need to include susceptor elements. Each of the susceptors may be in the form of elongated particles. The elongated particles may be aligned along the long axis of the aerosol-forming article. The elongated particles may also be aligned along the long axis of the aerosol-forming substrate. Each of the susceptors may be in the form of one or more strips made of susceptor material. An aerosol-forming article may comprise one or more strips of an aerosol-forming substrate laminated with one or more strips made of susceptor material. For example, an aerosol-forming article may comprise one or more strips of tobacco material laminated with one or more strips made of susceptor material.

[0453] The aerosol generator may comprise one or more susceptors. Each of the susceptors may be in the form of at least one blade or at least one pin. Advantageously, each of the susceptors may be reused with multiple aerosol-forming articles. Each of the susceptors may be configured to be inserted into the aerosol-generating substrate when the aerosol-generating article is received into the chamber. Advantageously, this may allow for a simpler and more sustainable configuration when using the aerosol-forming article.

[0454] Providing power to an external heater may include supplying a direct current to a resistive heating element. The method may further include not supplying a first current to the resistive heating element. The method may further include not supplying an alternating current to the resistive heating element. The method may further include supplying only a second current to the resistive heating element. Advantageously, this may mean that the resistive heating element does not have a magnetic interaction with the inductor element.

[0455] The method may further include providing a second current to the resistive heating element so that the resistive heating element is heated to at least 80°C. Advantageously, heating the resistive heating element to at least 80°C may ensure that the resistive heating element adequately heats the aerosol-forming substrate so that vapor can be generated. The method may further include providing a second current to the resistive heating element so that the resistive heating element is heated not to exceed 210°C. Advantageously, heating the resistive heating element not to exceed 210°C may ensure that the resistive heating element does not burn or char the aerosol-forming substrate, thereby ensuring that no aerosol is generated that produces undesirable compounds and causes the user to experience a burnt taste.

[0456] When an alternating magnetic field is generated by supplying an alternating current to an inductor element, the alternating magnetic field may induce an alternating current in the resistive heating element. Therefore, when a second current is supplied to the resistive heating element and the first current is supplied to the inductor element at the same time, the alternating current induced in the resistive heating element may affect the resistive heating feedback signal provided to the control circuit. For example, the alternating current induced in the resistive heating element may modify the resistive heating feedback signal provided to the control circuit. This may affect the control circuit's ability to accurately determine the temperature of the resistive heating element, and therefore its ability to maintain the temperature of the resistive heating element at or to follow the external heater target temperature profile.

[0457] Advantageously, if the method involves preventing the supply of a second current to the resistive heating element when a first current is supplied to the inductor element, the induced alternating current does not affect the resistive heating feedback signal. Therefore, the method can more accurately determine the temperature of the resistive heating element.

[0458] Similarly, the method may further include preventing the supply of the first current to the inductor element when the second current is supplied to the resistive heating element. The method may further include preventing the simultaneous supply of the first current to the inductor element and the second current to the resistive heating element.

[0459] When an alternating magnetic field is generated in the chamber by an alternating current in an inductor coil, depending on the configuration of adjacent resistive heating elements, the alternating magnetic field may induce an alternating current in the adjacent resistive heating elements. The resistive heating elements may be configured such that the total current induced in the resistive heating elements by the alternating magnetic field is substantially zero, as described in relation to the sixth aspect of this disclosure.

[0460] In a further embodiment of the eighth aspect, the internal heater may include an internal resistance heating element, and the external heater may include an external resistance heating element.

[0461] In this further embodiment, the first current may be a direct current such that providing power to the internal heater may include providing a direct current to the internal resistance heating element. The method may further include not supplying a second current to the internal resistance heating element. The method may further include supplying only the first current to the internal resistance heating element.

[0462] In this further embodiment, the second current may also be a direct current, such that providing power to the external heater may include providing a direct current to the external resistive heating element. The method may further include not supplying the first current to the external resistive heating element. The method may further include supplying only the second current to the external resistive heating element.

[0463] Advantageously, this may also mean that, when the first and second currents are supplied in an alternating manner, power is supplied from the power source to only one of the internal resistance heating element or the external resistance heating element at a time. As described above, this can advantageously ensure that the power source is utilized optimally and efficiently.

[0464] The method may further include providing a second current to the external resistive heating element and a first current to the internal resistive heating element so that the external resistive heating element and the internal resistive heating element are heated to at least 80°C. Advantageously, heating the external resistive heating element and the internal resistive heating element to at least 80°C may ensure that the external resistive heating element and the internal resistive heating element adequately heat the aerosol-forming substrate so that vapor can be generated. The method may further include providing a second current to the external resistive heating element and a first current to the internal resistive heating element so that the external resistive heating element and the internal resistive heating element are heated not to exceed 210°C. Advantageously, by heating the external and internal resistance heating elements so as not to exceed 210°C, it can be assured that the external and internal resistance heating elements will not burn or char the aerosol-forming substrate, and thereby it can be assured that aerosols that produce undesirable compounds and cause the user to perceive a burnt taste will not be generated.

[0465] In a further embodiment of the eighth aspect, the internal heater may include an internal resistance heating element, and the external heater may include an external induction heating element.

[0466] The internal resistance heating element may be placed inside the chamber. The internal resistance heating element may include at least one pin configured to be inserted into the aerosol generating substrate when the aerosol generating article is received inside the chamber. The internal resistance heating element may include at least one blade configured to be inserted into the aerosol generating substrate when the aerosol generating article is received inside the chamber. The internal resistance heating element may be configured to be resistively heated when a direct current is supplied.

[0467] In this further embodiment, the first current may be a direct current such that providing power to the internal heater may include providing a direct current to the internal resistance heating element. The method may further include not supplying a second current to the internal resistance heating element. The method may further include supplying only the first current to the internal resistance heating element.

[0468] In this further embodiment, the second current may be an alternating current such that providing power to an external heater may include providing an alternating current to an external induction heating element. The method may further include not supplying a first current to the external induction heating element. The method may further include supplying only a second current to the external induction heating element.

[0469] Advantageously, this may also mean that, when the first and second currents are supplied in an alternating manner, power is supplied from the power source to only one of the internal resistance heating element or the external induction heating element at a time. As described above, this can advantageously ensure that the power source is utilized optimally and efficiently.

[0470] The method may further include providing a first current to the internal resistance heating element so that the internal resistance heating element is heated to at least 80°C. Advantageously, heating the internal resistance heating element to at least 80°C may ensure that the internal resistance heating element adequately heats the aerosol-forming substrate so that vapor can be generated. The method may further include providing a first current to the internal resistance heating element so that the internal resistance heating element is heated not to exceed 210°C. Advantageously, heating the internal resistance heating element not to exceed 210°C may ensure that the internal resistance heating element does not burn or char the aerosol-forming substrate, thereby ensuring that no aerosol is generated that produces undesirable compounds and causes the user to perceive a burnt taste.

[0471] As used herein, the term “aerosol generator” is used to describe a device that interacts with an aerosol-forming substrate to generate an aerosol. Preferably, the aerosol generator is a smoking device that interacts with an aerosol-forming substrate to generate an aerosol that can be directly inhaled into the user’s lungs through the user’s mouth.

[0472] As used herein, the term "aerosol-forming substrate" refers to a substrate made of an aerosol-forming material having the ability to release volatile compounds upon heating in order to generate an aerosol, or a substrate containing such material.

[0473] The aerosol-forming substrate is preferably a solid aerosol-forming substrate. However, the aerosol-forming substrate may contain both solid and liquid components. Alternatively, the aerosol-forming substrate may be a liquid aerosol-forming substrate.

[0474] The aerosol-forming substrate preferably contains nicotine. More preferably, the aerosol-forming substrate contains tobacco. Alternatively, or additionally, the aerosol-forming substrate may contain a non-tobacco-containing aerosol-forming material.

[0475] When the aerosol-forming substrate is a solid aerosol-forming substrate, the solid aerosol-forming substrate may contain one or more of the following: herb leaves, tobacco leaves, tobacco stems, puffed tobacco, and homogenized tobacco, for example, one or more of the following: powder, granules, pellets, fragments, twisted yarn, splinters, or sheets.

[0476] Optionally, the solid aerosol-forming substrate may contain tobacco or non-tobacco volatile flavor compounds, which are released upon heating of the solid aerosol-forming substrate. The solid aerosol-forming substrate may also contain, for example, one or more capsules containing additional tobacco or non-tobacco volatile flavor compounds, which may melt during heating of the solid aerosol-forming substrate.

[0477] Optionally, the solid aerosol-forming substrate may be provided on or embedded within a thermally stable carrier. The carrier may take the form of a powder, granules, pellets, fragments, yarns, strips, or sheets. The solid aerosol-forming substrate may be deposited on the surface of the carrier, for example, in the form of a sheet, foam, gel, or slurry. The solid aerosol-forming substrate may be deposited over the entire surface of the carrier, or alternatively, in a pattern to provide non-uniform flavor delivery during use.

[0478] In preferred embodiments, the aerosol-forming substrate comprises homogenized tobacco material. As used herein, the term “homogenized tobacco material” refers to material formed by agglomerating particulate tobacco.

[0479] The aerosol-forming substrate preferably comprises an aggregate of homogenized tobacco material sheets. As used herein, the term “sheet” refers to a layered element having a width and length substantially greater than its thickness. As used herein, the term “aggregated” is used to describe a sheet that is wrapped, folded, or otherwise compressed or compressed substantially transversely with respect to the longitudinal axis of the aerosol-generating article. Preferably, the aerosol-forming substrate comprises an aerosol-forming compound. As used herein, the term “aerosol-forming compound” is used to describe any suitable known compound or mixture of compounds that facilitates aerosol formation during use and is substantially resistant to thermal decomposition at the operating temperature of the aerosol-generating article.

[0480] Suitable aerosol-forming materials are known in the art and include, but are not limited to, polyhydric alcohols such as propylene glycol, triethylene glycol, 1,3-butanediol, and glycerin; esters of polyhydric alcohols such as glycerol monoacetate, glycerol diacetate, and glycerol triacetate; and aliphatic esters of monocarboxylic acids, dicarboxylic acids, or polycarboxylic acids such as dimethyl dodecanediol and dimethyl tetradecanediol. Preferred aerosol-forming materials are polyhydric alcohols or mixtures thereof, such as propylene glycol, triethylene glycol, and 1,3-butanediol, and most preferably glycerin.

[0481] The aerosol-forming substrate may comprise a single aerosol-forming body. Alternatively, the aerosol-forming substrate may comprise a combination of two or more aerosol-forming bodies.

[0482] As used herein, the term “susceptor” refers to an element comprising a material having the ability to convert magnetic field energy into heat. When a susceptor is located in an alternating magnetic field, it is heated. The heating of the susceptor may be the result of at least one of hysteresis losses and eddy currents induced within the susceptor, depending on the electrical and magnetic properties of the susceptor material.

[0483] As used herein, the term “inductive coupling” refers to heating of a susceptor when it is penetrated by an alternating magnetic field. Heating may be caused by the generation of eddy currents within the susceptor. Heating may also be caused by magnetic hysteresis losses.

[0484] As used herein, the term "inhalation" means the act of a user inhaling an aerosol into their body through their mouth or nose.

[0485] As used herein, when referring to an aerosol generator, the terms “upstream” and “downstream” are used to describe the relative positions of components or parts of components of an aerosol generator with respect to the direction in which air flows through the aerosol generator during use. An aerosol generator according to the present invention may have a proximal end through which aerosol is discharged from the aerosol generator during use. The proximal end of an aerosol generator may also be called the mouth end or the downstream end. The mouth end is downstream of the distal end. The distal end of an aerosol generator may also be called the upstream end. Components or parts of components of an aerosol generator may be described as being upstream or downstream of each other based on their relative positions with respect to the airflow path of the aerosol generator. As used herein, when referring to an aerosol generating article, the terms “upstream” and “downstream” are used to describe the relative positions of components or parts of components of an aerosol generating article with respect to the direction in which air flows through the aerosol generating article during use. The aerosol generating article according to the present invention may have a proximal end through which an aerosol is drawn out of the aerosol generating article during use. The proximal end of the aerosol generating article may also be called the mouth end or the downstream end. The mouth end is downstream of the distal end. The distal end of the aerosol generating article may also be called the upstream end. Components or parts of components of the aerosol generating article may be described as being located upstream or downstream of each other based on their relative positions between the proximal end and the distal end of the aerosol generating article. The front of a component or part of a component of the aerosol generating article is the part closest to the upstream end of the aerosol generating article. The rear of a component or part of a component is the part closest to the downstream end of the aerosol generating article. [Examples]

[0486] The present invention is defined in the claims. However, a non-exclusive list of non-limiting embodiments is provided below. Any one or more features of these embodiments may be combined with any one or more features of other embodiments, forms, or aspects described herein.

[0487] Example 1. Aerosol generator, A chamber for receiving at least a portion of an aerosol-generating article, An inductor element positioned adjacent to or within the chamber, A resistance heating element positioned adjacent to or inside the chamber, At least one power supply for providing power to an inductor element and a resistive heating element, A control circuit configured to control the power supply from at least one power source to an inductor element and to a resistive heating element, The control circuit is configured to supply a first current to the inductor element so that the inductor element generates an alternating magnetic field within the chamber. An aerosol generator in which the control circuit is configured to supply a second current to a resistive heating element in order to heat the chamber. Example 2. The first current is an alternating current, as described in Example 1 of the aerosol generator. Example 3. The aerosol generator according to Example 1 or Example 2, wherein the control circuit is configured so that a second current is not supplied to the inductor element. Example 4. The aerosol generator according to any one of Examples 1 to 3, wherein the control circuit is configured so that no DC current is supplied to the inductor element. Example 5. The aerosol generator according to any one of Examples 1 to 4, wherein the control circuit is configured to supply only a first current to the inductor element. Example 6. The second current is a direct current, as described in any one of Examples 1 to 5 of the aerosol generator. Example 7. The aerosol generator according to any one of Examples 1 to 6, wherein the control circuit is configured so that a first current is not supplied to the resistive heating element. Example 8. The aerosol generator according to any one of Examples 1 to 7, wherein the control circuit is configured so that alternating current is not supplied to the resistive heating element. Example 9. The aerosol generator according to any one of Examples 1 to 8, wherein the control circuit is configured to supply only a second current to the resistive heating element. Example 10. The aerosol generator according to any one of Examples 1 to 9, wherein the power supply is a first DC power supply. Example 11. The first DC power source is a battery, as described in Example 10 of the aerosol generator. Example 12. The aerosol generator according to Example 10 or Example 11, wherein the control circuit comprises a DC / AC converter connected to a first DC power supply. Example 13. The aerosol generator according to Example 12 includes a DC / AC converter, a Class E power amplifier including a first transistor switch and an LC load network. Example 14. The aerosol generator according to any one of Examples 1 to 13, wherein the control circuit is configured to supply a second current to the resistive heating element so that the resistive heating element is heated to at least 80°C. Example 15. The aerosol generator according to any one of Examples 1 to 14, wherein the control circuit is configured to supply a second current to the resistive heating element so that the resistive heating element is heated so that it does not exceed 210°C. Example 16. The aerosol generator according to any one of Examples 1 to 15, wherein the control circuit is configured to provide a first current to an inductor element and a second current to a resistive heating element at different times. Example 17. The aerosol generator according to any one of Examples 1 to 16, wherein the control circuit is configured to provide a first current to an inductor element and a second current to a resistive heating element in an alternating sequence. Example 18. The aerosol generator according to any one of Examples 1 to 17, wherein the control circuit is configured to adjust the amplitude of a first current supplied to the inductor element to maintain the temperature of the susceptor element at a target temperature or to make it follow a susceptor target temperature profile. Example 19. The aerosol generator according to any one of Examples 1 to 18, wherein the control circuit is configured to adjust the amplitude of a second current supplied to the resistive heating element to maintain the temperature of the resistive heating element at a resistive heating target temperature or to follow a resistive heating target temperature profile. Example 20. The aerosol generator according to any one of Examples 1 to 19, wherein the control circuit is configured to block the supply of a second current to the resistive heating element when a first current is supplied to the inductor element. Example 21. The aerosol generator according to any one of Examples 1 to 20, wherein the control circuit is configured to block the supply of the first current to the inductor element when a second current is supplied to the resistive heating element. Example 22. The aerosol generator according to any one of Examples 1 to 21, wherein the control circuit is configured to prevent the simultaneous supply of a first current to the inductor element and a second current to the resistive heating element. Example 23. The aerosol generator according to any one of Examples 1 to 22, wherein the control circuit is configured to provide a first current to the inductor element during the ON period and to prevent the provision of the first current to the inductor element during the OFF period. Example 24. The aerosol generator according to Example 23, wherein the control circuit is configured to supply a first current to the inductor element in one or more pulses during each on-period, and the control circuit is configured to control the temperature of the susceptor element by adjusting the pulses during each on-period. Example 25. The aerosol generator according to Example 24, wherein the pulse occupies a proportion of each on-period, and the control circuit is configured to control the temperature of the susceptor element by adjusting the proportion of each on-period occupied by the pulse. Example 26. The aerosol generator according to any one of Examples 23 to 25, wherein the control circuit is configured to maintain the temperature of the susceptor element at the susceptor target temperature or to follow the susceptor target temperature profile by adjusting the length of the on period. Example 27. The aerosol generator according to any one of Examples 23 to 26, wherein the control circuit is configured to provide a second current to the resistive heating element during the off period. Example 28. The aerosol generator according to Example 27, wherein the control circuit is configured to maintain the temperature of the resistive heating element at the resistive heating target temperature or to follow the resistive heating target temperature profile by adjusting the length of the off period. Example 29. The aerosol generator according to Example 27 or Example 28, wherein the control circuit is configured to provide a second current to the resistive heating element with one or more pulses during each off period, and the control circuit is configured to control the temperature of the susceptor element by adjusting the pulses during each off period. Example 30. The aerosol generator according to Example 29, wherein a pulse occupies a proportion of each off period, and the control circuit is configured to control the temperature of the susceptor element by adjusting the proportion of each off period occupied by the pulse. Example 31. The aerosol generator according to Example 27 or Example 28, wherein the control circuit is configured to provide a second current to the resistive heating element for a reduced time period shorter than each off period during off periods. Example 32. The aerosol generator according to Example 31, wherein the control circuit is configured to maintain the temperature of the resistive heating element at the resistive heating target temperature or to follow the resistive heating target temperature profile by adjusting the length of the reduced time period. Example 33. The aerosol generator according to Example 31, wherein the control circuit is configured to maintain the temperature of the resistive heating element at the resistive heating target temperature or to follow the resistive heating target temperature profile by adjusting the length of the time gap between the reduced time period and the on period. Example 34. The aerosol generator according to any one of Examples 1 to 19, wherein the control circuit is configured to simultaneously provide a first current to an inductor element and a second current to a resistive heating element. Example 35. The inductor element surrounds the chamber, in the aerosol generator according to any one of Examples 1 to 34. Example 36. The resistance heating element surrounds the chamber, and the aerosol generator is as described in any one of Examples 1 to 35. Example 37. The aerosol generator according to any one of Examples 1 to 36, wherein the resistance heating element is configured to heat the periphery of the chamber. Example 38. The aerosol generator according to any one of Examples 1 to 37, wherein the resistive heating element is configured such that the total current induced within the resistive heating element by the alternating magnetic field is substantially zero. Example 39. The aerosol generator according to any one of Examples 1 to 38, wherein the resistance heating element comprises at least one primary portion and at least one secondary portion. Example 40. The aerosol generator according to Example 39, wherein the resistive heating element is configured such that the current induced in at least one primary portion by the alternating magnetic field is approximately equal to and opposite to the current induced in at least one secondary portion by the alternating magnetic field. Example 41. The aerosol generator according to Example 39 or Example 40, wherein at least one primary section is arranged such that a second current flows clockwise around the chamber within the primary section when viewed from the first end of the chamber, and at least one secondary section is arranged such that a second current flows counterclockwise around the chamber within the secondary section when viewed from the first end of the chamber, and the cumulative length of at least one primary section is substantially equal to the cumulative length of at least one secondary section. Example 42. The aerosol generator according to any one of Examples 39 to 41, wherein the resistance heating element comprises strictly one primary part and strictly one secondary part. Example 43. The aerosol generator according to Example 42, wherein the primary part is integrally formed with the secondary part. Example 44. The aerosol generator according to any one of Examples 39 to 41, wherein the resistance heating element is arranged in a serpentine shape and is folded or curved so as to at least partially enclose the chamber. Example 45. The aerosol generator according to Example 44, wherein the resistance heating element comprises two filaments arranged in a serpentine shape such that the two filaments are substantially parallel to each other, and the resistance heating element comprises a plurality of alternating primary and secondary parts. Example 46. The inductor element is an inductor coil, as described in any one of Examples 1 to 45 of the aerosol generator. Example 47. The inductor coil is a helical coil, as described in Example 45 of the aerosol generator. Example 48. The aerosol generator according to any one of Examples 1 to 47, wherein the resistive heating element is a resistive heating coil. Example 49. The resistance heating coil is a helical coil, as described in Example 48 of the aerosol generator. Example 50. The aerosol generator according to any one of Examples 1 to 49, wherein the inductor element is an inductor coil and the resistive heating element is a resistive heating coil. Example 51. The aerosol generator described in Example 50, wherein the resistance heating coil and the inductor coil are wound together. Example 52. The aerosol generator according to Example 50 or Example 51, wherein the resistance heating coil is wound around a winding axis and the inductor coil is wound around the same winding axis. Example 53. The aerosol generator further comprises a jacket, the jacket defining the chamber, as described in any one of Examples 1 to 52. Example 54. An aerosol generator according to Example 53, in which the resistance heating coil is wound around the outer surface of the jacket, as in Example 48. Example 55. The aerosol generator according to Example 53 or Example 54, as opposed to Example 46, wherein the inductor coil is wound around the outer surface of the jacket. Example 56. The jacket is a thermally conductive jacket, as described in any one of Examples 53 to 55 of the aerosol generating apparatus. Example 57. The thermal conductivity of the thermally conductive jacket is at least 20 Wm². -1 K -1 Preferably at least 30Wm -1 K -1 More preferably, at least 40 Wm -1 K -1 More preferably, about 80 Wm -1 K -1 The aerosol generator described in any one of Examples 53 to 56. Example 58. The jacket is a ceramic aerosol generator according to any one of Examples 53 to 57. Example 59. The aerosol generator according to Example 58, wherein the ceramic is alumina or aluminum nitrate. Example 60. The jacket has a circular cross-section, and the aerosol generator is as described in any one of Examples 53 to 59. Example 61. The aerosol generator according to any one of Examples 53 to 60, wherein the jacket has a substantially cylindrical shape. Example 62. The jacket has a longitudinal axis, and the aerosol generator is as described in any one of Examples 53 to 61. Example 63. The aerosol generator according to Example 62, wherein the jacket has an inner surface, the inner surface defining a chamber. Example 64. The aerosol generator according to Example 63, wherein the jacket has at least one groove defined on the inner surface of the jacket. Example 65. The aerosol generator according to Example 64, wherein at least one groove extends parallel to the longitudinal axis. Example 66. An aerosol generator according to any one of Examples 53 to 65, as dependent on Example 48, wherein the resistance heating coil is wound around a winding axis that coincides with the longitudinal axis of the jacket. Example 67. An aerosol generator according to any one of Examples 53 to 66, as dependent on Example 46, wherein the inductor coil is wound around a winding axis that coincides with the longitudinal axis of the jacket. Example 68. The aerosol generator according to any one of Examples 1 to 67, further comprising a housing, the housing at least partially enclosing the chamber. Example 69. The jacket is received within the housing, and the aerosol generator is as described in Example 68, in accordance with Example 48. Example 70. The aerosol generator according to Embodiment 69, wherein the inductor element is located inside the housing such that the inductor element at least partially surrounds the jacket and the resistive heating element. Example 71. An aerosol generator according to any one of Examples 1 to 70, wherein the inductor element extends between the first end and the second end. Example 72. The aerosol generator according to Example 71, wherein the electrical resistance between the first and second ends of the inductor element is less than 250 milliohms, preferably less than 150 milliohms, and more preferably about 100 milliohms. Example 73. The resistance heating element extends between the first end and the second end, in the aerosol generator according to any one of Examples 1 to 72. Example 74. The aerosol generator according to Example 73, wherein the electrical resistance between the first and second ends of the resistive heating element is 100 milliohms to 2000 milliohms, preferably 150 milliohms to 1500 milliohms, and more preferably 200 milliohms to 1000 milliohms. Example 75. The aerosol generator according to any one of Examples 1 to 74, wherein the electrical resistance of the resistive heating element is greater than the electrical resistance of the inductor element. Example 76. The aerosol generator according to Example 75, wherein the electrical resistance of the resistive heating element is at least twice as great as the electrical resistance of the inductor element. Example 77. An aerosol generator according to any one of Examples 1 to 76, wherein the inductor element comprises a first filament, and the first filament has a first cross-sectional area. Example 78. The aerosol generator according to Example 77, wherein the first cross-sectional area is defined within the first plane. Example 79. The aerosol generator according to Example 77 or Example 78, wherein the first cross-sectional area is perpendicular to the direction of extension of the first filament. Example 80. The aerosol generator according to any one of Examples 77 to 79, wherein the first cross-sectional area is perpendicular to the direction of extension of the first filament at the first and second ends of the inductor element. Example 81. The aerosol generator according to any one of Examples 77 to 80, wherein the first cross-sectional area is substantially constant between the first and second ends of the inductor element. Example 82. The aerosol generator according to any one of Examples 77 to 81, wherein the first cross-sectional area is perpendicular to the direction of the first current flow. Example 83. The first cross-sectional area is an aerosol generator according to any one of Examples 77 to 82, wherein the shape is substantially rectangular. Example 84. An aerosol generator according to any one of Examples 77 to 83, wherein the first cross-sectional area has a first width and a first thickness, and the first width is greater than the first thickness. Example 85. The aerosol generator according to Example 84, wherein the first width is at least 15 times greater than the first thickness. Example 86. The first width is 1 mm to 3 mm, an aerosol generator according to Example 84 or Example 85. Example 87. The first thickness is 0.05 mm to 0.2 mm, an aerosol generator according to any one of Examples 84 to 86. Example 88. An aerosol generator according to any one of Examples 84 to 87, dependent on Example 62, wherein the first width is parallel to the longitudinal axis of the jacket. Example 89. An aerosol generator according to any one of Examples 84 to 88, dependent on Example 67, wherein the first width is parallel to the winding axis of the inductor coil. Example 90. The first thickness is perpendicular to the longitudinal axis of the jacket, an aerosol generator according to any one of Examples 84 to 89 when dependent on Example 62. Example 91. The first thickness is perpendicular to the winding axis of the inductor coil, an aerosol generator according to any one of Examples 84 to 90 when dependent on Example 67. Example 92. The aerosol generator according to any one of Examples 1 to 91, wherein the resistance heating element comprises a second filament, and the second filament has a second cross-sectional area. Example 93. The aerosol generator according to Example 92, wherein the second cross-sectional area is defined within the first plane. Example 94. The aerosol generator according to Example 92 or Example 93, wherein the second cross-sectional area is perpendicular to the direction of extension of the second filament. Example 95. The aerosol generator according to any one of Examples 92 to 94, wherein the second cross-sectional area is perpendicular to the direction of extension of the second filament between the first and second ends of the resistance heating element. Example 96. The aerosol generator according to any one of Examples 92 to 95, wherein the second cross-sectional area is substantially constant between the first and second ends of the resistance heating element. Example 97. The aerosol generator according to any one of Examples 92 to 96, wherein the second cross-sectional area is perpendicular to the direction of the second current flow. Example 98. The second cross-sectional area is the aerosol generator according to any one of Examples 92 to 97, wherein the shape is substantially rectangular. Example 99. An aerosol generator according to any one of Examples 1 to 98, wherein the inductor element contains a metal, preferably copper. Example 100. The inductor element is made of copper, and the aerosol generator is as described in any one of Examples 1 to 99. Example 101. The aerosol generator according to any one of Examples 1 to 100, wherein the resistance heating element contains a metal, preferably stainless steel. Example 102. The resistance heating element is made of stainless steel, and the aerosol generator is as described in any one of Examples 1 to 101. Example 103. The aerosol generator according to any one of Examples 1 to 102, wherein the inductor element contains a material different from that of the resistive heating element. Example 104. An aerosol generator according to any one of Examples 1 to 103, wherein the inductor element is made of a different material from the resistive heating element. Example 105. Aerosol generator, A chamber for receiving at least a portion of an aerosol-generating article, An inductor element positioned adjacent to or within the chamber, A resistance heating element is provided, which is located adjacent to or inside the chamber. The inductor element comprises a first filament having a first cross-sectional area, the first cross-sectional area being defined in a first plane, The resistive heating element comprises a second filament including a second cross-sectional area, the second cross-sectional area also defined within the first plane. An aerosol generator in which the first cross-sectional area is larger than the second cross-sectional area. Example 106. Aerosol generator, A chamber for receiving at least a portion of an aerosol-generating article, An inductor element positioned adjacent to or within the chamber, A resistance heating element is provided, which is located adjacent to or inside the chamber. The inductor element contains copper, The resistance heating element is made of stainless steel and is used in aerosol generators. Example 107. Aerosol generation system, an aerosol generator described in any one of Examples 1 to 106, an aerosol generating article comprising an aerosol generating substrate, The aerosol generating article is received in the chamber of the aerosol generating device; this is an aerosol generating system. Example 108. The aerosol generating article comprises one or more susceptors, as described in Example 107. Example 109. The aerosol generating device is an aerosol generating system according to Example 107 or Example 108, comprising one or more susceptors. Example 110. The aerosol generating system according to Example 109, wherein one or more susceptors are configured to be inserted into the aerosol generating substrate when an aerosol generating article is received in the chamber. Example 111. During operation, one or more susceptors are heated by an inductor element, an aerosol generating system according to any one of Examples 107 to 110. Example 112. The aerosol generating substrate is an aerosol generating system according to any one of Examples 107 to 111, comprising a tobacco material. Example 113. An aerosol generating system according to any one of Examples 107 to 112, wherein an airflow channel is defined between the aerosol generating article and the jacket, and the airflow channel extends from the distal end of the jacket to the proximal end of the jacket. Example 114. The aerosol generating system according to Example 113, wherein an airflow channel is defined between an aerosol generating article and at least one groove. Example 115. The aerosol generating system according to Example 113 or Example 114, wherein the airflow path is defined from the distal end of the jacket through the airflow channel to the proximal end of the jacket, and also defined from the proximal end of the aerosol generating article through the aerosol generating article to the distal end of the aerosol generating article. Example 116. A method for generating aerosols by controlling an aerosol generation system, wherein the system is an aerosol generating article containing an aerosol generating substrate, an aerosol generator comprising an aerosol generator having a chamber for receiving at least a portion of an aerosol generating article, The aerosol generator is An inductor element positioned adjacent to or within the chamber, A resistance heating element positioned adjacent to or inside the chamber, At least one power supply for providing power to an inductor element and a resistive heating element, The system further comprises a control circuit configured to control the power supply from the power source to the inductor element and the resistive heating element, The method is, A step of providing a first current to an inductor element so that the inductor element generates an alternating magnetic field within the chamber, A method comprising the step of providing a second current to a resistive heating element in order to resistively heat the resistive heating element. Example 117. The aerosol generating article comprises one or more susceptors, according to the method of Example 116. Example 118. The aerosol generator comprises one or more susceptors, as described in Example 116 or Example 117. Example 119. The method according to any one of Examples 116 to 118, wherein one or more susceptors are configured to be inserted into the aerosol generating substrate when an aerosol generating article is received in the chamber. Example 120. The method according to any one of Examples 116 to 119, wherein providing a first current to an inductor element so that the inductor element generates an alternating magnetic field within a chamber includes heating one or more susceptors by the inductor element. Example 121. The method according to any one of Examples 116 to 120, further comprising adjusting the amount of heating provided by induction heating by adjusting a first current provided to an inductor element. Example 122. The method according to any one of Examples 116 to 121, further comprising adjusting the amount of heating provided by resistive heating by adjusting a second current supplied to a resistive heating element. Example 123. The method is the method of any one of Examples 116 to 122, further comprising adjusting the amplitude of a first current supplied to an inductor element to maintain the temperature of a susceptor element at a susceptor target temperature or to follow a susceptor target temperature profile. Example 124. The method according to any one of Examples 116 to 123, further comprising adjusting the amplitude of a second current supplied to the resistive heating element to maintain the temperature of the resistive heating element at a resistive heating target temperature or to follow a resistive heating target temperature profile. Example 125. The method is the method of any one of Examples 116 to 124, further comprising preventing the supply of a second current to a resistive heating element when a first current is supplied to an inductor element. Example 126. The method is the method of any one of Examples 116 to 125, further comprising preventing the supply of the first current to the inductor element when the second current is supplied to the resistive heating element. Example 127. The method is the method according to any one of Examples 116 to 126, further comprising preventing the simultaneous supply of a first current to the inductor element and the supply of a second current to the resistive heating element. Example 128. The method is the method according to any one of Examples 116 to 127, further comprising providing a first current to an inductor element during the ON period and preventing the provision of a first current to an inductor element during the OFF period. Example 129. The method according to Example 128, further comprising adjusting the length of the on-period to maintain the temperature of the susceptor element at a susceptor target temperature or to make it follow a susceptor target temperature profile. Example 130. The method according to Example 128 or Example 129, further comprising providing a first current to an inductor element with one or more pulses during each on-period, and further comprising controlling the temperature of a susceptor element by adjusting the pulses during each on-period. Example 131. The method according to Example 130, further comprising controlling the temperature of a susceptor element by adjusting the proportion of each on-period occupied by the pulse, wherein the pulse occupies a proportion of each on-period. Example 132. The method is the method according to any one of Examples 128 to 131, further comprising providing a second current to the resistive heating element during the off period. Example 133. The method according to Example 132, further comprising adjusting the length of the off period to maintain the temperature of the resistive heating element at the resistive heating target temperature or to make it follow the resistive heating target temperature profile. Example 134. The method according to Example 132 or Example 133, further comprising providing a second current to the resistive heating element with one or more pulses during each off period, and further comprising controlling the temperature of the resistive heating element by adjusting the pulses during each off period. Example 135. The method according to Example 134, further comprising controlling the temperature of a resistive heating element by adjusting the proportion of time the pulse occupies during each off period, wherein the pulse occupies a proportion of the time during each off period. Example 136. The method according to Example 132 or Example 133, further comprising providing a second current to the resistive heating element for a reduced time period shorter than the off period during the off period. Example 137. The method according to Example 136, further comprising adjusting the length of the reduced time period to maintain the temperature of the resistive heating element at the resistive heating target temperature or to make it follow the resistive heating target temperature profile. Example 138. The method according to Example 136, which may include maintaining the temperature of the resistive heating element at or following a resistive heating target temperature profile by adjusting the length of the time gap between the reduced time period and the on period. Example 139. The method is the method according to any one of Examples 116 to 124, further comprising simultaneously providing a first current to an inductor element and a second current to a resistive heating element. Example 140. The method is the method according to any one of Examples 116 to 139, further comprising, after the device is started, first providing a first current to an inductor element, and then providing a second current to a resistive heating element. Example 141. The method is the method of any one of Examples 116 to 139, further comprising, after the device is started, first providing a second current to a resistive heating element, and then providing a first current to an inductor element. Example 142. The method according to any one of Examples 116 to 141, further comprising adjusting the amount of heating provided by induction heating by adjusting the frequency of a first current during operation of the apparatus. Example 143. The method is the method of any one of Examples 116 to 142, further comprising adjusting the temperature of a susceptor to maintain it at a target temperature or to follow a target temperature profile by adjusting a first current supplied to an inductor element. Example 144. Aerosol generator, A chamber for receiving at least a portion of an aerosol-generating article, Internal heater, External heater and, At least one power supply for providing power to the internal heater and the external heater, A control circuit configured to control the power supply from at least one power source to an internal heater and to an external heater, The control circuit is further configured to block the power supply to one of the external heaters or the internal heaters when power is being supplied to the other of the external heaters or the internal heaters. Example 145. The aerosol generator according to Example 144, wherein the control circuit is configured to block the supply of power to the external heater when power is being supplied to the internal heater. Example 146. The aerosol generator according to Example 144 or Example 145, wherein the control circuit is configured to block the supply of power to the external heater when power is being supplied to the internal heater. Example 147. The aerosol generating apparatus according to any one of Examples 144 to 146, wherein the internal heater is configured to heat the aerosol generating article from an internal position within the aerosol generating article when at least a portion of the aerosol generating article is received in the chamber. Example 148. The aerosol generating apparatus according to any one of Examples 144 to 147, wherein the external heater is configured to heat the aerosol generating article from an external position outside the aerosol generating article when at least a portion of the aerosol generating article is received in the chamber. Example 149. An aerosol generator according to any one of Examples 144 to 148, wherein the control circuit is configured to supply a first current to an internal heater, and the control circuit is configured to supply a second current to an external heater. Example 150. The aerosol generator according to Example 149, wherein the control circuit is configured to provide a first current to an internal heater and a second current to an external heater at different times. Example 151. The aerosol generator according to Example 149 or Example 150, wherein the control circuit is configured to supply a first current to an internal heater, and then a second current to an external heater. Example 152. The aerosol generator according to any one of Examples 149 to 151, wherein the control circuit is configured to supply a first current to an internal heater over a first time period, and the control circuit is configured to supply a second current to an external heater over a second time period following the first time period. Example 153. The aerosol generator according to Example 149 or Example 150, wherein the control circuit is configured to supply a second current to an external heater, and then to supply a first current to an internal heater. Example 154. The aerosol generator according to any one of Examples 149, 150, or 153, wherein the control circuit is configured to supply a second current to an external heater over a first time period, and the control circuit is configured to supply a first current to an internal heater over a second time period following the first time period. Example 155. The aerosol generator according to any one of Examples 149 to 154, wherein the control circuit is configured to provide a first current to an internal heater and a second current to an external heater in an alternating sequence. Example 156. The aerosol generator according to any one of Examples 149 to 155, wherein the control circuit is configured to provide a first current to an internal heater based on an internal heating feedback signal, and the control circuit is configured to provide a second current to an external heater based on an external heating feedback signal. Example 157. An aerosol generator according to any one of Examples 149 to 156, wherein the internal heater comprises an inductor element and the external heater comprises a resistive heating element. Example 158. An aerosol generator according to any one of Examples 149 to 156, wherein the internal heater is equipped with an internal resistance heating element, and the external heater is equipped with an external resistance heating element. Example 159. An aerosol generator according to any one of Examples 149 to 156, wherein the internal heater is equipped with an internal resistance heating element, and the external heater is equipped with an external induction heating element. Example 160. Aerosol generation system, an aerosol generator described in any one of Examples 144 to 159, An aerosol generating system comprising an aerosol generating article equipped with an aerosol generating substrate, the aerosol generating article being received in the chamber of an aerosol generating device. Example 161. A method for generating aerosols by controlling an aerosol generation system, wherein the system is an aerosol generating article containing an aerosol-forming substrate, an aerosol generator comprising an aerosol generator having a chamber for receiving at least a portion of an aerosol generating article, The aerosol generator is Internal heater, External heater and, At least one power supply for providing power to the internal heater and the external heater, The system further comprises a control circuit configured to control the power supply from at least one power source to an internal heater and to an external heater, The method is, A step of supplying power to an internal heater so that the internal heater heats the aerosol-forming substrate from an internal position within the aerosol-forming substrate, A step of supplying power to an external heater so that the external heater heats the aerosol-forming substrate from an external position outside the aerosol-forming substrate, A method comprising the step of blocking the power supply to one of an external heater and an internal heater when power is being supplied to the other of the external heater and the internal heater. Example 162. The method is the method according to Example 161, which includes blocking the supply of power to an external heater when power is being supplied to an internal heater. Example 163. The method is the method according to Example 161 or Example 162, which includes blocking the supply of power to an internal heater when power is being supplied to an external heater. Example 164. The method according to any one of Examples 161 to 163, wherein providing power to an internal heater includes providing a first current to the internal heater, and providing power to an external heater includes providing a second current to the external heater. Example 165. The method according to Example 164, further comprising providing a first current to an internal heater and a second current to an external heater at different times. Example 166. The method according to Example 164 or Example 165, further comprising supplying a first current to an internal heater and then supplying a second current to an external heater. Example 167. The method according to any one of Examples 164 to 166, further comprising providing a first current to an internal heater over a first time period, and further comprising providing a second current to an external heater over a second time period after the first time period. Example 168. The method according to Example 164 or Example 165, further comprising supplying a second current to an external heater and then supplying a first current to an internal heater. Example 169. The method according to Example 164, Example 165, or Example 168, further comprising providing a second current to an external heater over a first time period, and further comprising providing a first current to an internal heater over a second time period after the first time period. Example 170. The method is the method according to any one of Examples 164 to 169, further comprising providing a first current to an internal heater and a second current to an external heater in an alternating sequence. Example 171. The method according to any one of Examples 164 to 170, further comprising providing a first current to an internal heater based on an internal heating feedback signal, and further comprising providing a second current to an external heater based on an external heating feedback signal. Example 172. The method according to any one of Examples 161 to 171, wherein the internal heater comprises an inductor element and the external heater comprises a resistive heating element. Example 173. The method according to any one of Examples 161 to 171, wherein the internal heater is equipped with an internal resistive heating element, and the external heater is equipped with an external resistive heating element. Example 174. The method according to any one of Examples 161 to 171, wherein the internal heater is equipped with an internal resistance heating element, and the external heater is equipped with an external induction heating element.

[0488] The present invention will be further described with reference to the accompanying drawings, which are for illustrative purposes only. [Brief explanation of the drawing]

[0489] [Figure 1] Figure 1 shows a side cross-sectional view of an aerosol generator according to the first embodiment. [Figure 2] Figure 2 shows an axial cross-sectional view of the aerosol generator in Figure 1 along line 1-1. [Figure 3] Figure 3 shows a perspective view of the heated assembly of the aerosol generator shown in Figures 1 and 2. [Figure 4] Figure 4 shows a side cross-sectional view of an aerosol generation system equipped with the aerosol generators shown in Figures 1 and 2. [Figure 5] Figure 5 shows a side cross-sectional view of an aerosol generator according to the second embodiment. [Figure 6] Figure 6 shows a side cross-sectional view of an aerosol generation system equipped with the aerosol generator shown in Figure 5. [Figure 7] Figure 7 shows a side cross-sectional view of an aerosol generator according to the third embodiment. [Figure 8] Figure 8 shows an axial cross-sectional view of the aerosol generator in Figure 7 along line 401-401. [Figure 9] Figure 9 shows a side cross-sectional view of an aerosol generator according to the fourth embodiment. [Figure 10] Figure 10 shows an axial cross-sectional view of the aerosol generator in Figure 9 along line 201-201. [Figure 11] Figure 11 shows a schematic diagram of the inductor element from the aerosol generator shown in Figure 9. [Figure 12A-B]Figures 12A and 12B show further arrangements of inductor elements and coil-shaped resistive heating elements for use in the aerosol generator according to the present invention. [Figure 13A-B] Figures 13A, 13B, and 13C show further arrangements of inductor elements and serpentine resistance heating elements for use in an aerosol generator according to the present invention. [Figure 13C] Figures 13A, 13B, and 13C show further arrangements of inductor elements and serpentine resistance heating elements for use in an aerosol generator according to the present invention. [Figure 13D] Figures 13D and 13E show further arrangements of the meandering resistance heating element for use in the aerosol generator according to the present invention. [Figure 13E] Figures 13D and 13E show further arrangements of the meandering resistance heating element for use in the aerosol generator according to the present invention. [Figure 14] Figure 14 is a block diagram showing the induction heating arrangement of the aerosol generator, which will be explained in relation to Figures 1 to 11. [Figure 15] Figure 15 is a schematic diagram showing the induction heating electrical circuit of the aerosol generator described in relation to Figures 1 to 11. [Figure 16] Figure 16 is a schematic diagram showing the resistance heating electrical circuit of the aerosol generator described in relation to Figures 1 to 11. [Figure 17] Figure 17 illustrates the application of DC current to the resistive heating element during the first operating stage and the application of AC current to the inductor element during the second operating stage. [Figure 18] Figure 18 is a block diagram showing further induction heating arrangements for the aerosol generator described in relation to Figures 1 to 11. [Figure 19] Figure 19 illustrates the switching voltage scheme for controlling the DC current supplied to the resistive heating element and the AC current supplied to the inductor element. [Figure 20]Figure 20 illustrates the resulting DC current to the resistive heating element and the AC current to the inductor element, which are caused by the switching voltage shown in Figure 19. [Figure 21] Figure 21 shows a side cross-sectional view of an aerosol generator according to an embodiment of the sixth aspect of the present disclosure. [Figure 22] Figure 22 shows an axial cross-sectional view of the aerosol generator in Figure 21 along line 1101-1101. [Figure 23] Figure 23 shows a side cross-sectional view of an aerosol generator according to an embodiment of the sixth aspect of the present disclosure. [Figure 24] Figure 24 shows an axial cross-sectional view of the aerosol generator in Figure 23 along line 1201-1201. [Figure 25] Figure 25 is a block diagram showing the heating arrangement of the aerosol generator, which will be explained in relation to Figures 23 and 24. [Figure 26] Figure 26 illustrates the switching voltage scheme for controlling the DC current supplied to the internal resistive heating element and the DC current supplied to the external resistive heating element. [Figure 27] Figure 27 illustrates the resulting DC current supplied to the internal resistive heating element and the DC current supplied to the external resistive heating element, both resulting from the switching voltage shown in Figure 26. [Modes for carrying out the invention]

[0490] Figures 1 and 2 show an aerosol generator 10 according to a first embodiment. Figure 1 shows a side cross-sectional view of the aerosol generator 10. Figure 2 shows an axial cross-sectional view of the aerosol generator 10 of Figure 1 along line 1-1. The aerosol generator 10 comprises a housing 12 that defines a chamber 16 for receiving a portion of an aerosol generating article. The chamber 16 comprises an open end 18 through which the aerosol generating article can be inserted into the chamber 16, and a closed end 20 located opposite the open end 18. The cylindrical wall 22 of the chamber 16 extends between the open end 18 and the closed end 20.

[0491] The cylindrical wall 22 of the chamber 16 is at least partially defined by the inner surface of the jacket 60, which is received within the housing 12. The jacket is substantially cylindrical in shape and has a circular cross-section. The jacket 60 is hollow and opens at its distal and proximal ends. The jacket 60 preferably contains ceramic, and more preferably contains alumina or aluminum nitrate. The inner surface of the jacket 60 defines a lumen 28 into which a portion of the aerosol-generating article is received when the aerosol-generating article is inserted into the chamber 16.

[0492] The aerosol generator 10 also includes an inductor element 24. The inductor element 24 is formed from a helical coil having a plurality of windings 26 arranged adjacent to and surrounding the chamber 16. The aerosol generator 10 also includes a resistive heating element 44. The resistive heating element 44 is also formed from a helical coil having a plurality of windings 46 arranged adjacent to and surrounding the chamber 16. The plurality of windings 26 of the inductor element 24 and the plurality of windings 46 of the resistive heating element 44 are located on the outer surface of the jacket 60. The jacket 60 is a thermally conductive heating jacket so that when the resistive element 44 is heated, heat is transferred from the resistive element 44 to the inner surface of the heating jacket 60. Advantageously, direct contact between the jacket 60 and the aerosol generating article facilitates heat transfer from the jacket 60 to the aerosol generating article.

[0493] The inductor element 24 and the resistive heating element 44 are helically wound around the central axis 36 of the aerosol generator 10 on the outer surface of the jacket 60. The central axis 36 of the aerosol generator 10 coincides with the long axis of the jacket 60. The jacket 60, the inductor element 24, and the resistive heating element 44 together form a heating assembly. The heating assembly is shown in Figure 3. As shown in Figure 3, the inductor element 24 and the resistive heating element 44 are wound together with each other.

[0494] The jacket 60 further comprises a plurality of grooves or airflow channels 62 extending along the longitudinal axis along the inner surface of the jacket 60. The longitudinal axis is parallel to the central axis 36. Each airflow channel 62 is defined on the inner surface of the jacket 60 and extends linearly from the distal end of the jacket 60 to the proximal end of the jacket 60. Advantageously, the plurality of airflow channels 62 allow air to flow from the distal end of the jacket 60 to the proximal end of the jacket 60, and a portion of the aerosol-generating article is received by the lumen 28 when the aerosol-generating article is inserted into the chamber 16.

[0495] The housing 12 also defines a number of projections 38 extending into the chamber 16 from the closed end 20 of the chamber 16. As will be further described below, the projections 38 function to maintain a gap between the end of the aerosol generating article and the closed end 20 of the chamber 16 when the aerosol generating article is fully inserted into the chamber 16. In the embodiments shown in Figures 1 and 2, the housing 12 defines three projections 38 that are equidistant from each other around the central axis 36 of the aerosol generator 10. Those skilled in the art will understand that the housing 12 may define a larger or smaller number of projections 38, and that the arrangement of the projections 38 at the closed end 20 of the chamber 16 may vary.

[0496] The aerosol generator 10 also includes a control circuit 40 and a power supply 42 connected to the inductor element 24 and the resistive heating element 44. The control circuit 40 is configured to provide alternating current from the power supply 42 to the inductor element 24 in order to generate an alternating magnetic field. The control circuit 40 is also configured to provide direct current from the power supply 42 to the resistive heating element 44 in order to generate heat within the resistive heating element 44 by Joule heating or resistive heating.

[0497] Figure 3 shows a perspective view of the heated assembly described in relation to Figures 1 and 2. The jacket 60 is shown as semi-transparent to reveal multiple airflow channels 62 extending from the distal end to the proximal end of the jacket 60.

[0498] The inductor element 24 is formed from a single filament, which contains copper. The inductor element 24 has a substantially rectangular cross-section perpendicular to the direction of alternating current flow through the inductor element 24. The rectangular cross-section of the inductor element 24 is substantially constant in size and shape with respect to substantially the entire length of the inductor element 24. In this embodiment, the cross-section of the inductor element 24 has a width parallel to the central axis 36 and the long axis of the jacket 60. The width of the cross-section of the inductor element 24 is 1 mm to 3 mm. In this embodiment, the cross-section of the inductor element 24 has a thickness perpendicular to the central axis 36 and the long axis of the jacket 60. The thickness of the cross-section of the inductor element 24 is 0.05 mm to 0.2 mm.

[0499] The resistive heating element 44 is formed from a single filament, which contains stainless steel. The resistive heating element 44 has a substantially rectangular cross-section perpendicular to the direction of direct current flow through the resistive heating element 44. The rectangular cross-section of the resistive heating element 44 is substantially constant in size and shape with respect to substantially the entire length of the resistive heating element 44. The rectangular cross-section of the resistive heating element 44 has a width parallel to the central axis 36 and the long axis of the jacket 60. The width of the cross-section of the resistive heating element 44 is 0.1 mm to 5 mm. In this embodiment, the rectangular cross-section of the resistive heating element 44 has a thickness perpendicular to the central axis 36 and the long axis of the jacket 60. The thickness of the cross-section of the resistive heating element 44 is 0.005 mm to 0.5 mm.

[0500] Figure 4 shows a cross-sectional view of an aerosol generating system 100 comprising the aerosol generating device 10 and aerosol generating article 102 shown in Figure 1.

[0501] The aerosol generating article 102 comprises an aerosol-forming substrate 104 in the form of a cigarette plug, a first hollow acetate tube 106, a second hollow acetate tube 108, a mouthpiece 110, and an outer wrapper 112. The aerosol generating article 102 also comprises a susceptor element 114 disposed within the aerosol-forming substrate 104. During use, a portion of the aerosol generating article 102 is inserted into the chamber 16 and the inductor element 24, thereby positioning the aerosol-forming substrate 104 and the susceptor element 114 within the lumen 28 defined by the inductor element 24. The control circuit 40 generates an alternating magnetic field that inductively heats the susceptor element 114 by supplying an alternating current from the power supply 42 to the inductor element 24, thereby heating the central region of the aerosol-forming substrate 104 and generating an aerosol. As will be explained in more detail below, the level of inductive coupling between the inductor element 24 and the susceptor element 114 (and consequently the heating of the susceptor 114) is affected by the frequency of the alternating current supplied to the inductor element 24. The control circuit 40 also heats the resistive heating element 44 by Joule heating or resistive heating by supplying a direct current to the resistive heating element 44 from the power supply 42. The heat from the resistive heating element 44 is transferred through the jacket 60 to the peripheral region of the aerosol-forming substrate 104, thereby heating the peripheral region of the aerosol-forming substrate 104 and generating an aerosol.

[0502] The airflow passing through the aerosol generating system 100 during use is illustrated by the dashed line 116 in Figure 3. When the user inhales the mouthpiece 110 of the aerosol generating article 102, a negative pressure is generated in the chamber 16. This negative pressure draws air into the chamber 16 through the open end 18 of the chamber. The air flowing into the chamber 16 then flows through a plurality of airflow channels 62 defined on the inner wall of the jacket 60. When the airflow reaches the closed end 20 of the chamber 16, the air flows into the aerosol generating article 102 through the aerosol forming substrate 104. The inflow of airflow into the aerosol generating article 102 is facilitated by a gap maintained between the upstream end of the aerosol generating article 102 and the closed end 20 of the chamber 16 by a plurality of protrusions 38. As the airflow passes through the aerosol forming substrate 104, the aerosol generated by the heating of the aerosol forming substrate 104 is carried into the airflow. Next, the aerosol flows along the length of the aerosol generating article 102 through the mouthpiece 110 to the user.

[0503] Figure 5 shows a cross-sectional view of the aerosol generator 150 according to the second embodiment. The aerosol generator 150 is similar to the aerosol generator 10 described with reference to Figures 1 and 2, and the same reference numerals are used to specify similar parts.

[0504] The aerosol generator 150 differs from the aerosol generator 10 in that it has an additional susceptor element 164. The susceptor element 164 has an elongated shape and extends into the chamber 16 from the closed end 20 of the chamber 16. The susceptor element 164 extends along the central axis 36 of the aerosol generator 150 such that the inductor element 24 extends concentrically around the susceptor element 164.

[0505] Figure 6 shows a cross-sectional view of an aerosol generating system 170 comprising the aerosol generating device 150 and aerosol generating article 172 shown in Figure 5. The aerosol generating system 170 is similar to the aerosol generating system 100 described with reference to Figure 4, and the same reference numerals are used to specify similar parts.

[0506] The aerosol generating system 170 differs from the aerosol generating system 100 in that there is no susceptor element within the aerosol generating article 172. When the aerosol generating article 172 is inserted into the chamber 16, the susceptor element 164 of the aerosol generating device 150 is received inside the aerosol forming substrate 104 of the aerosol generating article 172. Figures 4 and 5 show the susceptor element 164 having a pin-shaped or blade-shaped profile, so that the susceptor element 164 can easily penetrate the aerosol forming substrate 104 when the aerosol generating article 172 is inserted into the chamber 16 of the aerosol generating device 150. Those skilled in the art will understand that the susceptor element 164 may have a profile other than the one shown in Figures 5 and 6.

[0507] After the aerosol generating article 172 is inserted into the chamber 16, the operation of the aerosol generating system 170 is the same as the operation of the aerosol generating system 100, which will be described with reference to Figure 4.

[0508] Figures 7 and 8 show an aerosol generator 450 according to a third embodiment. Figure 7 shows a side cross-sectional view of the aerosol generator 450. Figure 8 shows an axial cross-sectional view of the aerosol generator 450 of Figure 7 along line 401-401. The aerosol generator 450 is also similar to the aerosol generator 10 described with reference to Figures 1 and 2, and the same reference numerals are used to specify similar parts.

[0509] The embodiment in Figure 7 differs from the embodiments in Figures 1 and 2 in the positioning of the inductor element 424. Instead of being located on the outer surface of the jacket 60, the inductor element 424, which has multiple windings 426,...

Claims

1. Aerosol generator, A chamber for receiving at least a portion of an aerosol-generating article, An inductor element that at least partially surrounds the chamber, A resistance heating element that at least partially surrounds the chamber, At least one power supply for providing power to the inductor element and the resistive heating element, The system comprises a control circuit configured to control the power supply from the at least one power source to the inductor element and to the resistive heating element, The control circuit is configured to supply a first current to the inductor element so that the inductor element generates an alternating magnetic field within the chamber in order to heat one or more susceptors within the aerosol generating article when the aerosol generating article is received into the chamber. The control circuit is configured to supply a second current to the resistive heating element in order to heat the chamber. An aerosol generator in which the inductor element at least partially surrounds the resistive heating element, or is wound together with the resistive heating element.

2. The aerosol generating apparatus according to claim 1, wherein the first current is an alternating current.

3. The aerosol generator according to claim 1 or 2, wherein the second current is a direct current.

4. The aerosol generator according to any one of claims 1 to 3, wherein the control circuit is configured such that the second current is not supplied to the inductor element, and the control circuit is configured such that the first current is not supplied to the resistive heating element.

5. The aerosol generating apparatus according to any one of claims 1 to 4, wherein the resistance heating element is configured to heat the periphery of the chamber.

6. The aerosol generator according to any one of claims 1 to 5, further comprising a jacket, the jacket defining the chamber.

7. The aerosol generating apparatus according to claim 6, wherein the resistance heating element is positioned on the outer surface of the jacket.

8. The aerosol generating apparatus according to claim 6 or 7, wherein the resistance heating element is a resistance heating coil.

9. The aerosol generator according to claim 8, wherein the resistance heating coil is wound around the outer surface of the jacket.

10. The aerosol generating apparatus according to claim 8 or 9, wherein the inductor element is an inductor coil.

11. The aerosol generating apparatus according to claim 10, wherein the inductor coil is wound around the outer surface of the jacket.

12. The aerosol generating apparatus according to claim 10, wherein the resistance heating coil and the inductor coil are wound together.

13. The aerosol generator further comprises a housing, the housing at least partially enclosing the chamber, The jacket is received within the housing, The aerosol generator according to any one of claims 6 to 12, wherein the inductor element is disposed inside the housing such that the inductor element at least partially surrounds the jacket and the resistive heating element.

14. The aerosol generating apparatus according to any one of claims 6 to 13, wherein the jacket comprises an electrical insulating material.

15. The aerosol generating apparatus according to any one of claims 6 to 14, wherein the jacket is made of an electrical insulating material.

16. The aerosol generator according to any one of claims 6 to 15, wherein the jacket comprises a material having a relative permeability of 0.9 to 1.1, preferably 0.99 to 1.

01.

17. The aerosol generator according to any one of claims 6 to 16, wherein the jacket comprises a material that is substantially transparent to the alternating magnetic field.

18. The aerosol generator according to any one of claims 6 to 17, wherein the jacket comprises ceramic.

19. The aerosol generator according to any one of claims 6 to 18, wherein the jacket comprises alumina or alumina nitrate.

20. The jacket is a thermally conductive jacket, and the thermal conductivity of the thermally conductive jacket is at least 20 Wm -1 K -1 Preferably at least 30 Wm -1 K -1 More preferably, at least 40 Wm -1 K -1 More preferably, about 80 Wm -1 K -1 The aerosol generating apparatus according to any one of claims 6 to 19.

21. The aerosol generating apparatus according to any one of claims 6 to 20, wherein the jacket has an inner surface, and the inner surface defines the chamber.

22. The aerosol generating apparatus according to claim 21, wherein the jacket is provided with at least one groove defined on the inner surface of the jacket.

23. The aerosol generating apparatus according to claim 22, wherein the at least one groove extends parallel to the longitudinal axis of the jacket.

24. The inductor element comprises a first filament, and the first filament comprises a first cross-sectional area. The first cross-sectional area is perpendicular to the direction of the first current flow, The aforementioned first cross-sectional area has a substantially rectangular shape, The resistive heating element comprises a second filament, and the second filament has a second cross-sectional area. The second cross-sectional area is perpendicular to the direction of current flow of the second current, The aerosol generator according to any one of claims 1 to 23, wherein the second cross-sectional area has a substantially rectangular shape.

25. The aerosol generator according to any one of claims 1 to 24, wherein the control circuit is configured to block the supply of the second current to the resistive heating element when the first current is supplied to the inductor element.

26. The aerosol generating apparatus according to any one of claims 1 to 25, wherein the resistive heating element is configured such that the total current induced within the resistive heating element by the alternating magnetic field is substantially zero.

27. The aforementioned resistance heating element comprises at least one primary portion and at least one secondary portion. The at least one primary portion is arranged such that the second current flows clockwise around the chamber within the at least one primary portion when viewed from the first end of the chamber, and the at least one secondary portion is arranged such that the second current flows counterclockwise around the chamber within the at least one secondary portion when viewed from the first end of the chamber. The aerosol generator according to any one of claims 1 to 26, wherein the cumulative length of the at least one primary portion is substantially equal to the cumulative length of the at least one secondary portion.

28. The aerosol generator according to any one of claims 1 to 27, wherein the aerosol generator comprises one or more susceptors.

29. The aerosol generating device according to claim 28, wherein the one or more susceptors are configured to be inserted into the aerosol generating substrate from within the aerosol generating article when the aerosol generating article is received in the chamber.

30. The aerosol generator according to claim 29, wherein the one or more susceptors are in the form of at least one blade or at least one pin.

31. The aerosol generating apparatus according to any one of claims 1 to 27, wherein the aerosol-forming article comprises one or more susceptors.

32. Aerosol generation system, an aerosol generator according to any one of claims 1 to 31, an aerosol generating article comprising an aerosol generating substrate, An aerosol generating system in which the aerosol generating article is received in the chamber of the aerosol generating device.

33. The aerosol generating system according to claim 32, wherein the aerosol-forming article comprises one or more susceptors.

34. The aerosol generating system according to claim 32, wherein the aerosol generating device comprises one or more susceptors.

35. The aerosol generating system according to claim 34, wherein one or more susceptors are configured to be inserted into the aerosol generating substrate when the aerosol generating article is received in the chamber.

36. The aerosol generating system according to any one of claims 32 to 35, wherein during operation, one or more susceptors are heated by the inductor element.

37. The aerosol generating system according to any one of claims 32 to 36, wherein the aerosol generating substrate includes a tobacco material.

38. The aerosol generating system according to any one of claims 32 to 37, wherein an airflow channel is defined between the aerosol generating article and the jacket, and the airflow channel extends from the distal end of the jacket to the proximal end of the jacket.

39. The aerosol generating system according to claim 38, wherein the airflow channel is defined between the aerosol generating article and at least one groove.

40. The aerosol generating system according to claim 39, wherein the airflow path is defined from the distal end of the jacket through the airflow channel to the proximal end of the jacket, and also defined from the proximal end of the aerosol generating article through the aerosol generating article to the distal end of the aerosol generating article.

41. A method for generating aerosols by controlling an aerosol generation system, wherein the system is an aerosol generating article containing an aerosol generating substrate, an aerosol generator comprising an aerosol generator having a chamber for receiving at least a portion of the aerosol generating article, The aerosol generating device is An inductor element that at least partially surrounds the chamber, A resistance heating element that at least partially surrounds the chamber, At least one power supply for providing power to the inductor element and the resistive heating element, The system further comprises a control circuit configured to control the power supply from the at least one power source to the inductor element and the resistive heating element, The inductor element surrounds the resistive heating element at least partially, or is wound together with the resistive heating element. The aforementioned method, The steps include: providing a first current to the inductor element so that the inductor element generates an alternating magnetic field within the chamber in order to heat one or more susceptors within the aerosol generating article when the aerosol generating article is received into the chamber; A method comprising the step of providing a second current to the resistive heating element in order to resistively heat the resistive heating element.

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