RU2819588C2 - Aerosol-generating device, aerosol-generating system and method of controlling aerosol-generating device - Google Patents

Abstract

FIELD: smoking accessories.

SUBSTANCE: group of inventions relates to the tobacco industry, namely to an aerosol-generating device, an aerosol-generating system, and a method for controlling the aerosol-generating device. Aerosol-generating device comprises an induction heating system configured to heat the aerosol-forming substrate and including current collector system, which is made with possibility of heating under action of penetrating variable magnetic field for heating of aerosol-forming substrate. Induction heating system includes at least the first inductance coil, at least the second inductance coil and controller. Controller is configured to excite the first inductance coil using the first alternating signal with pulse width modulation to generate the first alternating magnetic field for heating the first part of the current collector system. Controller is also configured to excite the second inductance coil using the second alternating signal with pulse width modulation to generate the second alternating magnetic field for heating the second part of the current collector system. Controller is configured to supply a first alternating pulse-width modulated signal and a second alternating pulse-width modulated signal with complementary duty cycles.

EFFECT: providing optimum heating of various aerosol-forming substrates.

26 cl, 13 dwg

Description

The present invention relates to an aerosol generating device having an induction heating system, a method for controlling an aerosol generating device having an induction heating system, and an aerosol generating system comprising an aerosol generating device having an induction heating system.

A number of electrical aerosol generating systems have been proposed in the prior art (see for example WO 2018073376 A1, A24F 47/00, 26.04.2018) in which an aerosol generating device having an electrical heater is used to heat an aerosol-forming substrate such as a tobacco plug. One of the objectives of such aerosol-generating systems is to reduce the amount of known harmful smoke components resulting from the combustion and pyrolytic decomposition of tobacco in conventional cigarettes. Typically, the aerosol generating substrate is provided as part of the aerosol generating article that is inserted into a cavity in the aerosol generating device. In some known systems, to heat the aerosol-forming substrate to a temperature at which it is capable of releasing volatile components that can form an aerosol, a resistive heating element, such as a heating blade, is inserted into or around the circumference of the aerosol-forming substrate when the article is placed in the aerosol-generating device. . Other aerosol generating systems use an induction heater instead of a resistive heating element. The induction heater typically includes an inductor forming part of the aerosol-generating device, and a current collector positioned such that it is in thermal proximity to the aerosol-generating substrate. The inductor generates an alternating magnetic field to create eddy currents and hysteresis losses in the pantograph, causing the pantograph to heat up and thereby heating the aerosol-forming substrate. Induction heating provides the ability to generate an aerosol without the heater affecting the aerosol-generating product. This makes it possible to increase the ease of cleaning of the heater.

Some known aerosol generating devices contain more than one inductor, each inductor being configured to heat a different portion of the current collector. Such aerosol generating devices can be used to heat different parts of the aerosol generating article at different times or to different temperatures. However, with such aerosol-generating devices, it may be difficult to heat one portion of the aerosol-generating article without also indirectly simultaneously heating an adjacent portion of the aerosol-generating article.

It would be desirable to provide an aerosol generating device that mitigates or eliminates these problems with prior art systems.

According to the present invention, there is provided an aerosol generating device comprising: an induction heating system configured to heat an aerosol-forming substrate and comprising a current collecting system that is configured to be heated by a penetrating alternating magnetic field to heat the aerosol-forming substrate, at least a first inductor and at least a second inductor and a controller, wherein the controller is configured to drive the first inductor with a first pulse-width modulated alternating signal to generate a first alternating magnetic field for heating the first portion of the current collector system, the controller is configured to drive the second coil inductance using a second pulse-width modulated alternating signal to generate a second alternating magnetic field for heating the second portion of the susceptor system, and the controller is configured to supply the first pulse-width modulated alternating signal and the second pulse-width modulated alternating signal with complementary duty cycles. .

As used herein, the term "duty duty" refers to the ratio of the amount of time during which a signal is present to the amount of time during which the signal is not present. The duty cycle is indicated as a percentage. A duty cycle of 60% means that the signal is on 60% of the time and that the signal is not on 40% of the time.

As used herein, the term “complementary duty cycles” refers to two signals of which one signal is supplied while the other signal is not supplied. The signals may have a sawtooth shape, with the second signal having an inverse sawtooth shape with respect to the first signal. The combined signals can result in continuous alternating current.

In some embodiments, the duty cycles of the first and second signals are smoothly shifted. In other words, the duty cycle of the first signal may be reduced while the duty cycle of the second signal may be increased, or vice versa.

The controller may be configured to provide a first pulse width modulated alternating signal to the first inductor during a first step to increase the temperature of the first portion of the current collector system from an initial temperature to a first operating temperature, wherein the controller may be configured to provide the first alternating signal with pulse width modulation during the first stage with a duty cycle greater than 50%, preferably greater than 60%, preferably greater than 70%, more preferably greater than 80%, and most preferably greater than 90%.

The controller may be configured to provide a first pulse width modulated alternating signal to the first inductor during a second step to reduce the temperature of the first portion of the current collector system from a first operating temperature to a second operating temperature, wherein the controller may be configured to provide the first alternating signal with pulse width modulation during the second stage with a duty cycle below 50%, preferably below 40%, preferably below 30%, more preferably below 20% and most preferably below 10%.

The controller may be configured to apply a second pulse width modulated alternating signal to the second inductor during the first step to increase the temperature of the second portion of the susceptor system from an initial temperature to a third operating temperature less than the first operating temperature, wherein the controller may be configured to supplying a second pulse width modulated alternating signal during the first step with a duty cycle below 50%, preferably below 40%, preferably below 30%, more preferably below 20% and most preferably below 10%.

The controller may be configured to apply a second pulse width modulated alternating signal to the second inductor during a second step to increase the temperature of the second portion of the susceptor system from a third operating temperature to a fourth operating temperature above the second operating temperature, wherein the controller may be configured to the ability to supply a second pulse width modulated alternating signal with a duty cycle greater than 50%, preferably greater than 60%, preferably greater than 70%, more preferably greater than 80%, and most preferably greater than 90%.

The controller may be configured to provide a first pulse-width modulated alternating signal during the first stage with a duty cycle greater than 80%, and the controller may be configured to provide a second pulse-width modulated alternating signal during the first stage with a duty cycle below 20% .

The controller may be configured to provide a first pulse-width modulated alternating signal during the first stage with a duty cycle greater than 90%, and the controller may be configured to provide a second pulse-width modulated alternating signal during the first stage with a duty cycle below 10% .

The controller may be configured to provide a first pulse width modulated alternating signal during the second stage with a duty cycle below 20%, and the controller may be configured to provide a second pulse width modulated alternating signal during the second stage with a duty cycle greater than 80% .

The controller may be configured to provide a first pulse width modulated alternating signal during the second stage with a duty cycle below 10%, and the controller may be configured to provide a second pulse width modulated alternating signal during the second stage with a duty cycle greater than 90% .

The aerosol generating device may further comprise a power source for supplying power to the induction heating system.

The controller may comprise a microcontroller.

The microcontroller may be configured to use a clock frequency of the microcontroller as one or both of the frequency of change of the first pulse-width modulated variable signal and the frequency of variation of the second pulse-width modulated variable signal.

The aerosol generating device may further comprise a generator for generating one or both of a frequency of change of the first pulse-width modulated alternating signal and a frequency of variation of the second pulse-width modulated alternating signal.

The controller may further comprise an oscillator for generating one or both of a frequency change of the first pulse-width modulated alternating signal and the second pulse-width modulated alternating signal.

The aerosol generating device may further comprise a first power stage comprising at least a first inductor and a first capacitor.

The first inductor and the first capacitor may be arranged as a first LC circuit.

The aerosol generating device may further comprise a second power stage comprising at least a second inductor and a second capacitor.

The second inductor and the second capacitor may be arranged as a second LC circuit.

According to the present invention, there is also provided an aerosol generating system comprising an aerosol generating device according to the present invention and an aerosol generating article containing an aerosol generating substrate.

The present invention also provides a method for controlling an aerosol-generating device, comprising: an induction heating system configured to heat an aerosol-forming substrate, and comprising: a current-collecting system that is configured to be heated by a penetrating varying magnetic field to heat the aerosol-forming substrate, at least at least a first inductor and at least a second inductor, and a controller that may be configured to drive the first inductor and the second inductor, the method comprising: driving the first inductor with a first pulse width modulated signal to generate a first alternating magnetic field for heating the first portion of the current collector system, energizing the second inductor with a second pulse width modulated signal to generate a second alternating magnetic field for heating the second portion of the current collector system, and providing a first pulse width modulation signal with a duty cycle complementary to duty cycle of the second signal with pulse width modulation.

A first pulse-width modulated alternating signal may be supplied to the first inductor during a first step to increase the temperature of the first portion of the susceptor system from an initial temperature to a first operating temperature, wherein the first pulse-width modulated alternating signal is supplied during the first step with a duty cycle higher 50%, preferably above 60%, preferably above 70%, more preferably above 80% and most preferably above 90%.

A first pulse-width modulated alternating signal may be supplied to the first inductor during a second step to reduce the temperature of the first portion of the current collector system from a first operating temperature to a second operating temperature, wherein the first pulse-width modulated alternating signal is supplied during the second step with a duty cycle below 50%, preferably below 40%, preferably below 30%, more preferably below 20% and most preferably below 10%.

A second pulse width modulated alternating signal may be supplied to the second inductor during the first step to increase the temperature of the second portion of the susceptor system from an initial temperature to a third operating temperature, wherein the second pulse width modulated alternating signal is supplied during the first step with a duty cycle lower 50%, preferably below 40%, preferably below 30%, more preferably below 20% and most preferably below 10%.

A second pulse-width modulated alternating signal may be supplied to the second inductor during a second step to increase the temperature of the second portion of the current collector system from a third operating temperature to a fourth operating temperature, wherein the second pulse-width modulated alternating signal is supplied during the second step with a duty cycle above 50%, preferably above 60%, preferably above 70%, more preferably above 80% and most preferably above 90%.

The first pulse-width modulated alternating signal may be supplied during the first step at a duty cycle of 80%, and the second alternating pulse-width modulated signal may be supplied during the first step at a duty cycle of 20%.

The first pulse-width modulated alternating signal may be supplied during the first stage at a duty cycle of 90%, and the second alternating pulse-width modulated signal may be supplied during the first stage at a duty cycle of 10%.

The first pulse-width modulated alternating signal may be supplied during the second stage at a duty cycle of 20%, and the second alternating pulse-width modulated signal may be supplied during the second stage at a duty cycle of 80%.

The first pulse-width modulated alternating signal may be supplied during the second stage with a duty cycle of 10%, and the second alternating pulse-width modulated signal may be supplied during the second stage with a duty cycle of 90%.

As used herein, the term “aerosol-forming substrate” means a substrate capable of releasing volatile compounds that can form an aerosol. Such volatile compounds may be released as a result of heating the aerosol-forming substrate. The aerosol-generating substrate is typically part of an aerosol-generating article.

As used herein, the term “aerosol-generating article” refers to an article containing an aerosol-forming substrate capable of releasing volatile compounds that can form an aerosol. For example, the aerosol generating product may be an article that generates an aerosol that is directly inhaled by a user drawing or puffing on a mouthpiece at the proximal or user end of the system. The aerosol generating article may be disposable. An article containing an aerosol-forming substrate containing tobacco may be referred to as a tobacco stick in the context of this document.

As used herein, the term “aerosol generating device” refers to a device that interacts with an aerosol-forming substrate to generate an aerosol.

As used herein, the term “aerosol generating system” refers to the combination of an aerosol generating device and an aerosol generating article. In an aerosol generating system, an aerosol generating article and an aerosol generating device cooperate to generate a respirable aerosol.

As used herein, the term "alternating pulse width modulated signal" includes any currents that vary over time to generate a varying magnetic field. The term "pulse width modulated alternating signal" is intended to include alternating currents. In case the alternating signal with pulse width modulation is an alternating current, then this alternating current generates an alternating magnetic field.

As used herein, the term “length” refers to the major dimension in the longitudinal direction of an aerosol generating device, or an aerosol generating article, or a component of an aerosol generating device, or an aerosol generating article.

As used herein, the term “width” refers to the major lateral dimension of an aerosol generating device, or an aerosol generating article, or a component of an aerosol generating device, or an aerosol generating article, at a particular location along its length. The term "thickness" refers to the dimension in the transverse direction perpendicular to the width.

As used herein, the term “cross-section” is used to describe the cross-section of an aerosol generating device, or an aerosol generating article, or a component of an aerosol generating device, or an aerosol generating article, in a direction perpendicular to the longitudinal direction at a particular location along its length.

As used herein, the term “proximal” refers to the user end or mouth end of an aerosol generating device or aerosol generating article. The proximal end of a component of an aerosol generating device or aerosol generating article is the end of the component closest to the user end or mouthpiece end of the aerosol generating device or aerosol generating article. As used herein, the term "far" refers to the end opposite the near end.

The first stage may have a specified duration. The second stage can have a specified duration. The duration of the first stage and the duration of the second stage may be the same. The duration of the second stage may differ from the duration of the first stage. This provides the advantage that the system can heat the first portion of the aerosol-forming substrate and the second portion of the aerosol-forming substrate for different periods of time. The duration of the second stage may be less than the duration of the first stage. The duration of the second stage may be longer than the duration of the first stage.

The duration of the first stage may be from about 50 seconds to about 200 seconds. The duration of the second stage is from about 50 seconds to about 200 seconds. The total duration of the first stage and the second stage may be from about 100 seconds to about 400 seconds. The total duration of the first stage and the second stage may be from about 150 seconds to about 300 seconds.

In some embodiments, the system further includes a puff sensor configured to detect a user taking a puff on the aerosol receiving system. In these embodiments, the duration of the first stage may be based on a first predetermined number of puffs detected by the puff sensor. The first predetermined number of puffs may be from 2 to 5. In these embodiments, the duration of the second stage may be based on the second predetermined number of puffs detected by the puff sensor. The second predetermined number of puffs may be from 2 to 5. In these embodiments, the total duration of the first stage and the second stage may be based on the total predetermined number of puffs detected by the puff sensor. The total specified number of puffs can range from 3 to 10 puffs by the user.

In some preferred embodiments, the first stage ends after the first maximum number of puffs is detected, or sooner if the first maximum duration is reached. The first maximum number of puffs may be from 2 to 5, and the first maximum duration may be from 50 seconds to approximately 200 seconds.

In some preferred embodiments, the second stage ends after the second maximum number of puffs is detected, or sooner if the second maximum duration is reached. The second maximum number of puffs may be from 2 to 5, and the second maximum duration may be from 50 seconds to approximately 200 seconds.

The first pulse width modulated alternating signal may be adjusted such that the temperature of the first portion of the current collector system increases from an initial temperature in accordance with a first operating temperature profile. The first temperature profile represents the change in the specified desired temperature of the first part of the current collector system over time. At any given point in time, if the actual temperature of the first part of the susceptor system differs from the temperature on the first temperature profile at the same point in time, then adjust the first pulse-width modulated variable signal so that

adjust the temperature of the first part of the current collector system to the temperature specified by the first temperature profile at a given time.

Likewise, the second pulse width modulated variable signal may be adjusted to increase the temperature of the second portion of the current collector system from an initial temperature according to a second temperature profile. The second temperature profile represents the change in the specified desired temperature of the second part of the current collector system over time. At any given point in time, if the actual temperature of the second part of the susceptor system differs from the temperature on the second temperature profile at the same point in time, then a second variable signal with pulse width modulation is adjusted to regulate the temperature of the second part of the susceptor system to the temperature specified by the second temperature profile at a given moment in time.

In some embodiments, the first operating temperature profile is substantially constant. In some embodiments, the first operating temperature profile changes over time.

In some embodiments, the second operating temperature profile is substantially constant. In some embodiments, the second operating temperature profile changes over time.

In some embodiments, during at least a portion of the first stage, the first operating temperature profile exceeds the second operating temperature profile. In these embodiments, during at least a portion of the first stage, the first operating temperature profile exceeds the second operating temperature profile by at least about 50 degrees Celsius. The first operating temperature profile may exceed the second operating temperature profile throughout the first stage.

In some embodiments, in the second stage, the first operating temperature profile and the second operating temperature profile are substantially the same. In some embodiments, in the second stage, the second operating temperature profile is within about 5 degrees Celsius of the first operating temperature profile.

In some embodiments, during at least a portion of the second stage, the second operating temperature profile exceeds the first operating temperature profile. In these embodiments, in a second step, the second operating temperature profile may exceed the first operating temperature profile by no more than about 50 degrees Celsius.

In some embodiments, the first operating temperature profile is substantially constant during at least a portion of the first stage. The first operating temperature profile may be constant during the first stage.

In some embodiments, the first operating temperature profile is substantially constant during at least a portion of the second stage. The first operating temperature profile may be constant during the second stage.

In some embodiments, the second operating temperature profile is substantially constant during at least a portion of the second stage. The second operating temperature profile may be constant during the second stage.

The first operating temperature profile may set a temperature from about 180 degrees Celsius to 300 degrees Celsius during at least a portion of the first stage. The first operating temperature profile may set a temperature from about 160 degrees Celsius to about 260 degrees Celsius during at least a portion of the second stage. The second operating temperature profile may set a temperature from about 180 degrees Celsius to about 300 degrees Celsius during at least a portion of the second stage.

The current collecting system can have any suitable shape. The current collection system may have a monolithic design. The current collection system may contain a variety of monolithic structures. The current collecting system can be extended. The current collection system can have any suitable cross-section. For example, the current collector system may have a circular, elliptical, square, rectangular, triangular, or other polygonal cross-section.

In some embodiments, the current collector system may include an internal heating element. As used herein, the term “internal heating element” refers to a heating element configured to be inserted into an aerosol-forming substrate.

In some embodiments, the current collection system may be configured to penetrate the aerosol-forming substrate when the aerosol-forming substrate is received by the device. In these embodiments, the internal heating element is preferably configured to be inserted into the aerosol-forming substrate. The internal heating element may be in the form of a plate. The internal heating element may be in the form of a pin. The internal heating element may be cone-shaped. If the aerosol generating device includes a device cavity for receiving an aerosol-forming substrate, then preferably an internal heating element extends into said device cavity.

In some embodiments, the current collector system may be an external heating element. As used herein, the term “outer heating element” refers to a heating element configured to heat the outer surface of the aerosol-forming substrate. The outer heating element is preferably configured to at least partially surround the aerosol-forming substrate upon receiving the aerosol-forming substrate by the aerosol generating device. The susceptor system may be configured to heat the outer surface of the aerosol-forming substrate when the aerosol-forming substrate is received by the cavity of the susceptor system.

The current collection system may be configured to substantially surround the aerosol-forming substrate when the device receives the aerosol-forming substrate.

The current collection system may include a cavity for receiving an aerosol-forming substrate. The current collecting system may comprise an outer side and an inner side opposite to the outer side. The inner side may at least partially define a cavity of the susceptor system for receiving the aerosol-forming substrate. The first part of the current collecting system may be tubular and form part of the cavity of the current collecting system. The second part of the current collecting system may be tubular and form part of the cavity of the current collecting system.

In some embodiments, the susceptor system includes a plurality of internal cavities for receiving an aerosol-forming substrate. The internal cavity of the first current collecting system part may define a first current collecting system cavity, and the internal cavity of the second current collecting system part may define a second current collecting system cavity.

In some preferred embodiments, the susceptor system includes one internal cavity for receiving an aerosol-forming substrate. In these embodiments, the internal cavity of the first susceptor system part forms a part of the specified one internal cavity of the susceptor system, and the internal cavity of the second susceptor system part forms a second part of the specified one internal cavity of the susceptor system. In some preferred embodiments, the current collector system is a tubular current collector system. The inner surface of the tubular current collector system may form a current collector system cavity.

In those embodiments in which the aerosol generating device includes a device cavity for receiving an aerosol-forming substrate, the current collection system may at least partially surround said device cavity. The cavity of the current collector system may be aligned with the cavity of the device.

In some embodiments, the current collector system includes at least one internal heating element and at least one external heating element.

The current collector system contains at least one current collector. The current collector system may contain one current collector. The current collector system may consist of one current collector. The first part of the current collector system may include a first current collector. The second part of the pantograph system may comprise a second pantograph.

As used herein, the term "susceptor" refers to an element containing a material that is capable of converting electromagnetic energy into heat. When the pantograph is in a changing magnetic field, the pantograph heats up. Heating of the pantograph may result from at least one of hysteresis losses and eddy currents induced in the pantograph, depending on the electrical and magnetic properties of the pantograph material.

The current collector may comprise any suitable material. The current collector can be made of any material that can be inductively heated to a temperature sufficient to aerosolize the aerosol-forming substrate. Preferred pantographs can be heated to temperatures in excess of about 250 degrees Celsius. Preferred current collectors may be made of electrically conductive material. As used herein, the term "electrically conductive" refers to materials having an electrical resistivity less than or equal to 1×10 ^-4 ohm meter (Ohm⋅m) at twenty degrees Celsius. Preferred current collectors may be made of a thermally conductive material. As used herein, the term "thermal conductive material" is used to describe a material having a volumetric thermal conductivity of at least 10 watts per meter Kelvin (W/(m⋅K)) at 23 degrees Celsius and 50 percent relative humidity, as measured using the method modified transient plane source (MTPS).

Suitable materials for the current collector include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, nickel, nickel compounds, titanium and composite metal materials. Some preferred current collectors contain metal or carbon. Some preferred current collectors contain ferromagnetic material, such as ferritic iron, a ferromagnetic alloy such as ferromagnetic steel or stainless steel, ferromagnetic particles and ferrite. Some preferred current collectors are composed of ferromagnetic material. A suitable pantograph may contain aluminum. A suitable pantograph may consist of aluminum. The pantograph may contain at least about 5 percent, at least about 20 percent, at least about 50 percent, or at least about 90 percent ferromagnetic or paramagnetic materials.

Preferably, the current collector is made of a material that is substantially impermeable to gas. In other words, preferably, the current collector is made of a material that is impermeable to gas.

The current collector of the current collecting system may have any suitable shape. For example, the pantograph may be elongated. The pantograph may have any suitable cross-section. For example, a pantograph may have a circular, elliptical, square, rectangular, triangular, or other polygonal cross-section.

The first part of the current collector system may be a tubular current collector. The second part of the current collector system may be a tubular current collector. The tubular current collector contains an annular housing facing the internal cavity. The pantograph cavity may be configured to receive an aerosol-forming substrate. The pantograph cavity may be an open cavity. The pantograph cavity may be open at one end. The pantograph cavity can be open at both ends.

In some multiple pantograph embodiments, all pantographs may be substantially identical. For example, the second pantograph may be substantially identical to the first pantograph. All current collectors can be made of the same material. All pantographs can have the same shape and size. By making each pantograph identical to the other pantographs, each pantograph can be heated to substantially the same temperature and at substantially the same rate when a given varying magnetic field is applied.

In some embodiments, the second pantograph differs from the first pantograph in at least one characteristic. The second pantograph may be made of a material different from the material of the first pantograph. The shape and dimensions of the second pantograph may be different from the shape and dimensions of the first pantograph. The second pantograph may have a length that is greater than the length of the first pantograph. By making each pantograph different from other pantographs, each pantograph can be adapted to provide optimal heating for different aerosol-forming substrates.

In one example, the first aerosol-forming substrate may require heating to a first temperature to generate a first aerosol with the desired characteristics, and the second aerosol-forming substrate may require heating to a second temperature different from the first temperature to generate a second aerosol with the desired characteristics. In this example, the first susceptor may be made of a first material suitable for heating the first aerosol-forming substrate to a first temperature, and the second susceptor may be made of a second material different from the first material and suitable for heating the second aerosol-forming substrate to a second temperature.

In another example, the aerosol-generating article may comprise a first aerosol-forming substrate having a first length, and a second aerosol-forming substrate having a second length different from the first length such that when the second aerosol-forming substrate is heated, a different amount of aerosol is generated than when the first is heated. aerosol-forming substrate. In this embodiment, the first pantograph may have a length substantially equal to the first length, and the second pantograph may have a length substantially equal to the second length.

In some preferred embodiments, the first pantograph is an elongated tubular pantograph and the second pantograph is also an elongated tubular pantograph. In these preferred embodiments, the first pantograph and the second pantograph may be substantially aligned. In other words, the first pantograph and the second pantograph may be axially aligned.

The current collector system may contain any suitable number of current collectors. The current collector system may contain a plurality of current collectors. The current collector system may contain at least two current collectors. For example, the current collector system may contain three, four, five or six current collectors. If the pantograph system contains more than two pantographs, an intermediate element may be placed between each two adjacent pantographs.

In some preferred embodiments, the current collector may comprise a current collecting layer provided on the support body. In embodiments with a first pantograph and a second pantograph, each of the first pantograph and the second pantograph may be formed of a support body and a pantograph layer. When a pantograph is placed in a changing magnetic field, eddy currents are induced in the immediate vicinity of the pantograph surface, that is, an effect called the surface effect is created. Accordingly, it is possible to construct the pantograph from a relatively thin layer of pantograph material while simultaneously ensuring efficient heating of the pantograph in the presence of a changing magnetic field. By constructing the current collector from a support body and a relatively thin current collecting layer, it is possible to simplify the production of an aerosol generating product that is simple, inexpensive and reliable.

The support body may be made of a material that is resistant to induction heating. This provides the advantage of being able to reduce those surfaces of the pantograph that are not in contact with the aerosol-forming substrate, the surfaces of the support body forming those surfaces of the pantograph that are not in contact with the aerosol-forming substrate.

The support body may contain electrically insulating material. As used herein, the term "electrical insulating" refers to materials having an electrical resistivity of at least 1×10 ⁴ ohm meter (Ω⋅m) at twenty degrees Celsius.

The support body may be thermally insulating. As used herein, the term "thermal insulating material" is used to describe a material having a volumetric thermal conductivity less than or equal to approximately 40 Watts per meter Kelvin (W/(m⋅K)) at a temperature of 23 degrees Celsius and 50 percent relative humidity, when measured using the Modified Transient Planar Source (MTPS) method.

By making the support body from a heat-insulating material, it is possible to create a heat-insulating barrier between the current-receiving layer and other components of the induction heating system, such as an inductor surrounding the current-receiving system. This has the advantage of being able to reduce heat transfer between the current collector and other components of the induction heating system.

The support body may be a tubular support body, and a current collecting layer may be provided on an inner surface of the tubular support body. By providing the current-receiving layer on the inner surface of the support body, it is possible to place the current-receiving layer adjacent to the aerosol-forming substrate in the cavity of the current-receiving system, which improves heat transfer between the current-receiving layer and the aerosol-forming substrate.

In some preferred embodiments with a first pantograph and a second pantograph, the first pantograph comprises a tubular support body made of a thermally insulating material and a current collector layer on an inner surface of the tubular support body. In some preferred embodiments, the second current collector includes a tubular support body made of thermal insulating material and a current collector layer on the inner surface of the tubular support body.

The pantograph may be provided with a protective outer layer, such as a protective ceramic layer or a protective glass layer. The protective outer layer makes it possible to increase the strength of the pantograph and simplify cleaning of the pantograph. The protective outer layer may substantially surround the current collector.

The current collector may contain a protective coating made of glass, ceramics or inert metal.

The susceptor system may include a space between a first susceptor system portion and a second susceptor system portion.

Said gap may be of any suitable size for thermally insulating the first part of the current collecting system from the second part of the current collecting system.

The current collecting system may include an intermediate element located between the first part of the current collecting system and the second part of the current collecting system. The intermediate element may be located in the space between the first part of the current collecting system and the second part of the current collecting system. The intermediate element may extend between the first part of the current collecting system and the second part of the current collecting system. The intermediate element may contact the end of the first part of the current collecting system. The intermediate element may contact the end of the second part of the current collecting system. The intermediate element may be attached to the end of the first part of the current collecting system. The intermediate element may be attached to the end of the second part of the current collecting system. The intermediate element may connect the second part of the current collecting system to the first part of the current collecting system. If the intermediate member connects the second portion of the current collection system to the first portion of the current collection system, then the intermediate member may provide structural support for the current collection system. Preferably, said intermediate element allows the current-receiving system to be constructed as a single one-piece element and can be easily removed and replaced in the induction heating system.

The intermediate element may have any suitable shape. The intermediate element may have any suitable cross-section. For example, the intermediate element may have a circular, elliptical, square, rectangular, triangular or other polygonal cross-section. The intermediate element may be tubular. The tubular intermediate element contains an annular body forming an internal cavity. The intermediate element may be configured to allow gas to penetrate from the outside of the intermediate element into said internal cavity. The cavity of the intermediate element may be configured to receive a portion of the aerosol-generating article. The cavity of the intermediate element may be an open cavity. The spacer cavity may be open at one end. The cavity of the intermediate element can be open at both ends.

In some preferred embodiments, the first pantograph system portion and the second pantograph system portion are tubular pantographs, and the intermediate member is a tubular intermediate member. In these embodiments, the tubular first pantograph, tubular second pantograph, and tubular intermediate member may be substantially aligned. The tubular first current collector, the tubular intermediate element and the tubular second current collector can be placed end to end in the form of a tubular rod. The internal cavities of the tubular first pantograph, the tubular intermediate member, and the tubular second pantograph may be substantially aligned. The internal cavities of the tubular first pantograph, the tubular intermediate element and the tubular second pantograph may form a cavity of the pantograph system.

The intermediate element may be made of any suitable material.

In preferred embodiments, the intermediate element is made of a material different from the material of the first current collector system part and the second current collector system part.

The intermediate element may contain thermal insulating material for thermally insulating the first part of the current collecting system from the second part of the current collecting system. The intermediate element may comprise a material having a volumetric thermal conductivity of less than or equal to approximately 100 milliwatts per meter Kelvin (mW/(m⋅K)) at a temperature of 23 degrees Celsius and a relative humidity of 50 percent, as measured using a modified transient plane source method ( MTPS). By providing an intermediate element made of a heat-insulating material in the space between the first current collecting system part and the second current collecting system part, it is possible to further reduce heat transfer between the first current collecting system part and the second current collecting system part. This provides the advantage of being able to improve the ability of the susceptor system to selectively heat specific areas of the aerosol-forming substrate. This also makes it possible to reduce the size of the gap between the first part of the current collection system and the second part of the current collection system and thus the ability to reduce the size of the current collection system.

The intermediate element may contain electrically insulating material for electrically insulating the first part of the current collecting system from the second part of the current collecting system. The current collector may comprise a material having an electrical resistivity of at least 1×10 ⁴ ohm meter (Ohm⋅m) at twenty degrees Celsius.

The intermediate element may comprise at least one of: thermal insulating material for thermally insulating the first part of the current collecting system from the second part of the current collecting system; and an electrical insulating material for electrically insulating the first part of the current collecting system from the second part of the current collecting system. In some preferred embodiments, the intermediate member comprises thermally insulating material for thermally insulating a first susceptor system portion from a second susceptor system portion and electrically insulating material for electrically insulating a first susceptor system portion from a second susceptor system portion.

Particularly preferred materials for the spacer may include polymeric materials such as polyetheretherketone (PEEK), liquid crystal polymers such as Kevlar®, certain types of cement, glass and ceramic materials such as zirconia (ZrO2), silicon nitride (Si3N4) and oxide aluminum (Al2O3).

The intermediate element may be gas permeable. In other words, the intermediate element is configured to allow gas to penetrate through the intermediate element. Typically, the intermediate element is configured to allow gas to pass from one side of the intermediate element to the other side of the intermediate element. The intermediate element may comprise an outer side and an inner side opposite the outer side. The intermediate element may be configured to allow gas to penetrate from the outside to the inside.

In some embodiments, the intermediate member includes an air passage configured to allow air to flow through the intermediate member. In these embodiments, the intermediate element does not necessarily have to be made of a gas-permeable material. Accordingly, in some embodiments

the intermediate element is made of a gas-tight material and contains an air channel configured to allow air to pass through the intermediate element. The intermediate element may contain several air channels. The intermediate element may include any suitable number of air passages, such as two, three, four, five or six air passages. In case the intermediate element contains several air passages, these air passages may be located at regular intervals in the intermediate element.

If the intermediate element is a tubular intermediate element defining an internal cavity, the intermediate element may include an air passage configured to allow air flow from the outer surface of the intermediate element into said internal cavity. The intermediate element may include an air passage extending from the outer surface to the inner surface. In the event that the tubular intermediate member contains multiple air passages, these air passages may be spaced at regular intervals around the circumference of the tubular intermediate member.

The first inductor is configured such that a varying electric current supplied to the first inductor results in the generation of a varying magnetic field. The first inductor is positioned relative to the susceptor system such that a varying electric current supplied to the first inductor produces a varying magnetic field that heats the first portion of the susceptor system.

The second inductor is configured such that a varying electric current supplied to the second inductor results in the generation of a varying magnetic field. The second inductor is positioned relative to the susceptor system such that a varying electric current supplied to the second inductor produces a varying magnetic field that heats the second portion of the susceptor system.

The inductor can be of any suitable shape. For example, the inductor may be a planar inductor. The planar inductor may be wound in a spiral pattern substantially in one plane. Preferably, the inductor is a tubular inductor defining an internal cavity. Typically, a tubular inductor is wound in a spiral around an axis. The inductor coil can be extended. Particularly preferably, the inductor may be an elongated tubular inductor. The inductor can have any suitable cross-section. For example, the inductor may have a circular, elliptical, square, rectangular, triangular, or other polygonal cross-section.

The inductor can be made of any suitable material. The inductor is made of electrically conductive material. Preferably, the inductor is made of metal or a metal alloy.

In case the inductor is a tubular inductor, a part of the current collecting system is located inside the inner cavity of the inductor. Particularly preferably, the first inductor is a tubular inductor, and at least a portion of the first part of the current collecting system is located within the internal cavity of the first inductor. The length of the tubular first inductor may be substantially equal to the length of the first part of the current collecting system. Particularly preferably, the second inductor is a tubular inductor, and at least a portion of the second part of the current collecting system is located inside the inner cavity of the second inductor. The length of the tubular second inductor may be substantially equal to the length of the second portion of the current collecting system.

In some embodiments, the second inductor is substantially identical to the first inductor. In other words, the first inductor and the second inductor have the same shape, size and number of turns. Particularly preferably, the second inductor is substantially identical to the first inductor in those embodiments in which the second susceptor system portion is substantially identical to the first susceptor system portion.

In some embodiments, the second inductor is different from the first inductor. For example, the second inductor may have a different length, number of turns, or cross-section than the first inductor. Particularly preferably, the second inductor is different from the first inductor in those embodiments in which the second susceptor system portion is different from the first susceptor system portion.

The first inductor and the second inductor may be placed in any suitable system. Particularly preferably, the first inductor and the second inductor are coaxially aligned along the axis. In case the first inductor and the second inductor are elongated tubular inductors, the first inductor and the second inductor may be coaxially aligned along the longitudinal axis such that the internal cavities of the coils are aligned along the longitudinal axis.

In some embodiments, the first inductor and the second inductor are wound in the same direction. In some embodiments, the second inductor is wound in a direction different from the winding direction of the first inductor.

The induction heating system may contain any suitable number of inductors. The current collecting system contains a plurality of inductors. The induction heating system contains at least two inductors. Preferably, the number of inductors of the induction heating system is equal to the number of current collectors of the current collecting system. The number of inductors of the induction heating system may differ from the number of current collectors of the current collector system. In case the number of inductors is equal to the number of pantographs, preferably each inductor is placed around a pantograph. Particularly preferably, each inductor extends substantially the length of the pantograph around which it is placed.

The current collection system may contain a flow concentrator. A flux concentrator may be placed around the inductor coil of an induction heating system. The flux concentrator is configured to deform the changing magnetic field generated by the inductor in the direction of the current-collecting system.

Preferably, due to the deformation of the magnetic field in the direction of the current collecting system, the magnetic flux concentrator allows the magnetic field to be concentrated on the current collecting system. This makes it possible to improve the efficiency of the induction heating system compared to embodiments in which a flux concentrator is not provided. In the context of this document, the phrase "concentrate a magnetic field" means: deform a magnetic field so that the magnetic energy density of the magnetic field increases at the location where the magnetic field is "concentrated."

As used herein, the term "flux concentrator" refers to a component that has a high relative magnetic permeability and serves to concentrate and direct the magnetic field or magnetic field lines generated by the inductor. As used herein, the term "relative permeability" refers to the ratio of the magnetic permeability of a material or medium, such as a flux concentrator, to the magnetic permeability of free space, "μ ₀ ", where μ ₀ is 4π×10 ^-7 Newtons per square Ampere (NA ^-2 ).

As used herein, the term “high relative magnetic permeability” refers to a relative magnetic permeability of at least 5 at 2-5 degrees Celsius, for example at least 10, at least 20, at least 30, at least 40, at least 50, at least 60, at least 80 or at least 100 degrees Celsius. These exemplary values preferably refer to relative magnetic permeability values at a frequency of 6 to 8 megahertz (MHz) and a temperature of 25 degrees Celsius.

The flow concentrator may be made of any suitable material or combination of materials.

Preferably, the flux concentrator contains a ferromagnetic material, such as a ferrite material, ferrite powder held in a binder, or any other suitable material containing a ferritic material, such as ferritic iron, ferromagnetic steel or stainless steel.

In some embodiments, the induction heating system includes a flux concentrator positioned around the first inductor and the second inductor. In these embodiments, the flux concentrator is configured to deform the varying magnetic field generated by the first inductor toward the first susceptor system portion and deform the varying magnetic field generated by the second inductor toward the second susceptor system portion.

In some of these embodiments, the flux concentrator portion extends within the intermediate member between the first current collector system portion and the second current collector system portion. By extending the flux concentrator portion into the intermediate element between the first susceptor system portion and the second susceptor system portion, the magnetic field generated by the first inductor and the magnetic field generated by the second inductor can be further deformed. This additional deformation allows

an additional concentration of the magnetic field generated by the first inductor towards the first part of the current collecting system, and an additional concentration of the magnetic field generated by the second inductor towards the second part of the current collecting system. This provides the opportunity to further improve the efficiency of the induction heating system.

In some embodiments, the induction heating system includes a plurality of flux concentrators. In some preferred embodiments, a separate flux concentrator is placed around each inductor. By providing each inductor with a dedicated flux concentrator, the flux concentrator can be optimally configured to deform the magnetic field generated by the inductor. Such a system also makes it possible to construct an induction heating system from modular induction heating blocks. Each induction heating block may include an inductor and a flux concentrator. By providing modular induction heating blocks, it is possible to promote standardized production of the induction heating system and the ability to remove and replace individual blocks.

In some preferred embodiments, the induction heating system comprises: a first flux concentrator positioned around the first inductor and configured to deform a varying magnetic field generated by the first inductor toward a first portion of the current collector system; and a second flux concentrator disposed around the second inductor and configured to deform the changing magnetic field generated by the second inductor toward the second portion of the current collecting system.

In these preferred embodiments, a portion of the first flux concentrator may extend within an intermediate member between the first susceptor system portion and the second susceptor system portion. In these preferred embodiments, a portion of the second flux concentrator may extend within the intermediate member between the first current collector system portion and the second current collector system portion. Due to the passage of part of the flux concentrator inside the intermediate element between the pantographs, the flux concentrator has the possibility of additional deformation of the magnetic field generated by the inductor in the direction of the pantograph.

The induction heating system may further comprise an induction heating system housing. The housing can hold together the current collector system, inductors and flux concentrators. This provides the ability to help secure the relative positions of the components of the induction heating system and improve communication between the components. Preferably, the casing of the induction heating system is made of an electrically insulating material.

In the case where the induction heating system includes separate induction heating blocks comprising an inductor and a flux concentrator, each induction heating block may include an induction heating block housing. The induction heating block casing can hold the components of the induction heating block together and improve the connection between the components. Preferably, the casing of the induction heating unit is made of an electrically insulating material.

The aerosol generating device may include a power source. The power source may be any suitable type of power source. The power source may be a DC power supply. In some preferred embodiments, the power source is a battery, such as a rechargeable lithium-ion battery. The power source may be another type of charge storage device, such as a capacitor. The power supply may need to be recharged. The power source may have a capacity that can store sufficient energy for one or more uses of the device. For example, the power source may have a capacity sufficient to enable continuous generation of an aerosol for a period of approximately six minutes, which corresponds to the typical time required to smoke a conventional cigarette, or for a period that is a multiple of six minutes. In yet another example, the power supply may have a capacity sufficient to enable a given number of device usage sessions or individual activations. In one embodiment, the power supply is a DC power supply having a DC supply voltage in the range of about 2.5 Volts to about 4.5 Volts and a DC supply current in the range of about 1 Ampere to about 10 Amps (corresponding to DC power supply power ranging from approximately 2.5 Watts to approximately 45 Watts).

The aerosol generating device may include a controller coupled to an induction heating system and a power source. In particular, the aerosol generating device may include a controller coupled to the first inductor, the second inductor, and a power supply. The controller is configured to control the power supply to the induction heating system from the power source. The controller may include a microprocessor, which may be a programmable microprocessor, a microcontroller, or an application specific integrated circuit (ASIC), or other electronic circuit capable of providing control. The controller may contain additional electronic components. The controller may be configured to control the supply of current to the induction heating system. Current may be supplied to the induction heating system continuously upon activation of the aerosol generating device, or it may be supplied intermittently, such as from puff to puff.

The aerosol generating device may preferably include a DC-to-AC inverter, which may include a Class C, Class D, or Class E power amplifier. The DC-to-AC inverter may be located between the power supply and the induction heating system.

The aerosol generating device may further comprise a DC/DC converter coupled between the power source and the DC/AC converter.

The aerosol generating device may include a first switch connected between the power source and the first inductor, and a second switch connected between the power source and the second inductor. The controller may be configured to open and close the first switch at a first switching frequency to drive a first pulse width modulated alternating signal in the first inductor while the second switch remains open. The controller may be configured to close and open the second switch at a second switching frequency to drive a second pulse width modulated alternating signal in the second inductor while the first switch remains open.

The controller may be configured to provide a pulse width modulated alternating signal to the induction heating system at any suitable frequency. The controller may be configured to provide an alternating pulse width modulated signal to the induction heating system at a frequency of about 5 kilohertz to about 30 megahertz. In some preferred embodiments, the controller is configured to provide an alternating pulse width modulated signal to the induction heating system at a frequency of from about 5 kilohertz to about 500 kilohertz. In some embodiments, the controller is configured to provide a pulse width modulated high frequency alternating signal to the induction heating system. As used herein, the term “high-frequency pulse-width modulated alternating signal” means a pulse-width modulated alternating signal having a frequency of from about 500 kilohertz to about 30 megahertz. The high frequency alternating signal with pulse width modulation may have a frequency of from about 1 megahertz to about 30 megahertz, such as from about 1 megahertz to about 10 megahertz, or, for example, from about 5 megahertz to about 8 megahertz.

The aerosol generating device may include a device housing. The device casing can be extended. The device housing may comprise any suitable material or combination of materials. Examples of suitable materials include metals, alloys, plastics or composite materials containing one or more of such materials, or thermoplastic materials suitable for use in the food or pharmaceutical industries, for example polypropylene, polyetheretherketone (PEEK) and polyethylene. Preferably, the material is light and non-fragile.

The device housing may define a device cavity for receiving an aerosol-forming substrate. The cavity of the device may be configured to receive at least a portion of the aerosol generating article. The cavity of the device can have any suitable shape and size. The cavity of the device may be substantially cylindrical. The device cavity may have a substantially circular cross-section.

The current-receiving system can be placed in the cavity of the device. The current collection system may be placed around the cavity of the device. If the susceptor system is a tubular susceptor system, then the susceptor system may surround a cavity of the device. The inner surface of the current collecting system may form an inner surface of the device cavity.

The first inductor and the second inductor may be placed in the cavity of the device. The first inductor and the second inductor may be placed around the cavity of the device. The first inductor and the second inductor may surround the device cavity. The inner surface of the first inductor and the second inductor may define an inner surface of the device cavity.

The device may have a proximal end and a distal end opposite the proximal end. Preferably, the device cavity is located at the proximal end of the device.

The device cavity may have a proximal end and a distal end opposite the proximal end. The proximal end of the device cavity may be substantially open to receive the aerosol generating article.

In some embodiments, the aerosol generating device further includes a cover movable over a proximal end of the device cavity to prevent insertion of the aerosol generating article into the device cavity.

In some preferred embodiments, the first inductor is located near the proximal end of the device cavity and the second inductor is located near the distal end of the device cavity. In these preferred embodiments, the controller may be configured to initiate heating of the aerosol-forming substrate by driving a first varying current in the first inductor and subsequently driving a second pulse-width modulated variable signal in the second inductor. This action causes the proximal portion of the device cavity to heat before heating the distal portion of the device cavity.

The device housing may include an air inlet. The air inlet hole may be configured to allow ambient air to enter the device housing. The device housing may include any suitable number of air inlet openings. The device housing may include a plurality of air inlet openings.

The device housing may include an air outlet. The air outlet may be configured to allow air to enter the device cavity from within the device housing. The device housing may include any suitable number of air outlets. The device housing may include a plurality of air outlets.

If the current collector system intermediate member is gas-permeable, the aerosol generating device may define an air flow path extending from the air inlet to the current collector system intermediate member. Such an air flow path allows air to be drawn through the aerosol generating device from the air inlet into the cavity of the device through the intermediate element.

In some embodiments, the device cavity includes a proximal end and a distal end opposite the proximal end. In these embodiments, the device cavity may be open at the proximal end to receive the aerosol generating article. In these embodiments, the device cavity may be substantially closed at the distal end. The device body may include an air outlet at a distal end of the device cavity. The aerosol generating device may further comprise an annular seal at the proximal end of the device cavity. The ring seal may extend into the cavity of the device. The O-ring provides a substantially airtight seal between the body of the device and the outer surface of the aerosol generating article housed in the cavity of the device. This provides the ability to reduce the volume of air drawn into the device cavity during use through any gaps that are present between the outer surface of the aerosol generating article and the inner surface of the device cavity. This makes it possible to increase the volume of air drawn into the aerosol generating article through the permeable intermediate elements.

In some embodiments, the device body includes a mouthpiece. The mouthpiece may include at least one air inlet and at least one air outlet. The mouthpiece may include more than one air inlet. The one or more air inlets provide the ability to reduce the temperature of the aerosol before delivery to the user and the ability to reduce the concentration of the aerosol before delivery to the user.

In some embodiments, a mouthpiece is provided as part of an aerosol generating article. As used herein, the term “mouthpiece” refers to a portion of an aerosol generating system placed in the mouth of a user to directly inhale the aerosol generated by the aerosol generating system from an aerosol generating article housed in the aerosol generating device.

In some embodiments, the controller may be configured to monitor the supply of current to the induction heating system. The controller may be configured to determine the temperature of the current collector system based on the monitored current. The controller may be configured to monitor the first varying current and determine the temperature of the first portion of the susceptor system based on the monitored first varying current. The controller may be configured to monitor the second varying current and determine the temperature of the second portion of the susceptor system based on the monitored second varying current.

The aerosol generating device may include a temperature sensor. The second temperature sensor may be configured to measure the temperature of the current collector system. The controller may be configured to regulate the first varying current based on the temperature of the current collector system as measured by the temperature sensor. The controller may be configured to regulate the second varying current based on the temperature of the current collector system as measured by the temperature sensor.

The temperature sensor may be any suitable type of temperature sensor. For example, the temperature sensor may be a thermocouple, a negative temperature coefficient RTD, or a positive temperature coefficient RTD.

In some preferred embodiments, the aerosol generating device may include a first temperature sensor configured to measure the temperature of the first portion of the current collector system. In these embodiments, the controller may be configured to regulate the first varying current based on the temperature of the first portion of the susceptor system as measured by the first temperature sensor.

In some preferred embodiments, the aerosol generating device may include a second temperature sensor configured to measure the temperature of the second portion of the current collector system. In these embodiments, the controller may be configured to regulate the second varying current based on the temperature of the second portion of the susceptor system as measured by the second temperature sensor.

The aerosol generating device may include a user interface for activating the device, such as a button to initiate heating of the aerosol generating device.

The aerosol generating device may include a display for displaying the status of the device or the aerosol generating substrate.

The aerosol generating device may include a sensor for detecting the presence of an aerosol-forming substrate. In the event that the aerosol generating device includes a device cavity for receiving an aerosol-forming substrate, the aerosol generating device may include a sensor for detecting the presence of an aerosol-forming substrate in said device cavity. If the aerosol generating device is configured to receive at least a portion of the aerosol generating device, the aerosol generating device may include an aerosol generating product sensor configured to detect the aerosol generating product in the cavity of the device.

The controller may be configured to initiate heating by driving a first varying current in the first inductor if the presence of an aerosol-forming substrate is detected by the aerosol-forming substrate sensor.

The controller may be configured to initiate heating by driving a first varying current in the first inductor if the aerosol generating article sensor detects the presence of an aerosol generating article in the cavity of the device.

The aerosol-generating substrate sensor and the aerosol-generating article sensor can be any suitable type of sensor. For example, the sensor may be an optical, acoustic, capacitive or inductive sensor.

The aerosol generating device may include a puff sensor configured to detect a user taking puffs on the aerosol generating system. As used herein, the term “pull” refers to a pull exerted by a user on an aerosol generating system for receiving an aerosol.

Preferably, the aerosol generating device is portable. The aerosol generating device may be of a size comparable to that of a traditional cigar or cigarette. The aerosol generating device may have an overall length of from about 30 millimeters to about 150 millimeters. The aerosol generating device may have an outer diameter of from about 5 millimeters to about 30 millimeters.

The aerosol generating device may form part of an aerosol generating system.

The aerosol generating system may further comprise an aerosol generating article. The aerosol-generating article may contain an aerosol-forming substrate. The aerosol-generating article may comprise a first aerosol-forming substrate and a second aerosol-forming substrate. When placing an aerosol-generating article in a device cavity, at least a portion of the first aerosol-forming substrate may be placed in a first portion of the device cavity, and at least a portion of a second aerosol-forming substrate may be placed in a second portion of the device cavity.

The current-receiving system, forming part of the induction heating system of the aerosol-generating device, is configured to heat the aerosol-forming substrate.

The aerosol-forming substrate may contain nicotine. The nicotine-containing aerosol-forming substrate may be a nicotine salt matrix.

The aerosol-forming substrate may be a liquid. The aerosol-forming substrate may contain solid components and liquid components. Preferably, the aerosol-forming substrate is solid.

The aerosol-forming substrate may contain material of plant origin. The aerosol-forming substrate may contain tobacco. The aerosol-forming substrate may comprise tobacco-containing material containing volatile tobacco flavor compounds that are released from the aerosol-forming substrate when heated. The aerosol-forming substrate may comprise non-tobacco material. The aerosol-forming substrate may comprise homogenized material of plant origin. The aerosol-forming substrate may comprise homogenized tobacco material. Homogenized tobacco material can be obtained by agglomerating tobacco into particles. In a particularly preferred embodiment, the aerosol-forming substrate comprises an assembled corrugated sheet of homogenized tobacco material. As used herein, the term “corrugated sheet” means a sheet having a plurality of substantially parallel folds or corrugations.

The aerosol-forming substrate may contain at least one aerosol-forming substance. An aerosol forming agent is any suitable known compound or mixture of compounds which, when used, promotes the formation of a dense and stable aerosol and which is substantially resistant to thermal decomposition at the operating temperature of the system. Suitable aerosol-forming agents are well known in the art and include, but are not limited to: polyhydric alcohols such as triethylene glycol, 1,3-butanediol and glycerol; polyhydric alcohol esters such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate. Preferred aerosol formers may include polyhydric alcohols or mixtures thereof, such as triethylene glycol, 1,3-butanediol.

Preferably, the aerosol-forming agent is glycerol. If present, the aerosol forming agent content of the homogenized tobacco material will be equal to 5 percent by weight or greater than 5 percent by weight on a dry weight basis, such as from about 5 percent to about 30 percent by weight on a dry weight basis. The aerosol-forming substrate may contain other additives and ingredients, such as flavoring agents.

The aerosol-forming substrate may be contained in the aerosol-generating article. The aerosol generating device comprising an induction heating system may be configured to accommodate at least a portion of the aerosol generating article. The aerosol generating article may have any suitable shape. The aerosol generating article may have a substantially cylindrical shape. The aerosol generating article may be substantially elongated. The aerosol generating article may have a length and a circumference substantially perpendicular to the length.

The aerosol-forming substrate may be provided in the form of an aerosol-generating segment containing the aerosol-forming substrate. The aerosol generating segment may contain a plurality of aerosol-forming substrates. The aerosol generating segment may comprise a first aerosol-forming substrate and a second aerosol-forming substrate. In some embodiments, the second aerosol-forming substrate is substantially the same as the first aerosol-forming substrate. In some embodiments, the second aerosol-forming substrate is different from the first aerosol-forming substrate.

In case the aerosol generating segment contains a plurality of aerosol-forming substrates, the number of aerosol-forming substrates may be the same as the number of susceptors in the susceptor system. Likewise, the number of aerosol-forming substrates may be the same as the number of inductors in the induction heating system.

The aerosol generating segment may have a substantially cylindrical shape. The aerosol generating segment may be substantially elongated. The aerosol generating segment may also have a length and a circumference substantially perpendicular to the length.

In the event that the aerosol-generating segment contains a plurality of aerosol-forming substrates, the aerosol-forming substrates may be arranged end-to-end along the axis of the aerosol-generating segment. In some embodiments, the aerosol generating segment may comprise a gap between adjacent aerosol generating substrates.

In some preferred embodiments, the aerosol generating article may have an overall length of from about 30 millimeters to about 100 millimeters. In some embodiments, the aerosol generating article has an overall length of approximately 4 to 5 millimeters. The aerosol generating article may have an outer diameter of from about 5 millimeters to about 12 millimeters. In some embodiments, the aerosol generating article may have an outer diameter of approximately 7.2 millimeters.

The aerosol generating segment may have a length of from about 7 millimeters to about 15 millimeters. In some embodiments, the aerosol generating segment may be approximately 10 millimeters or 12 millimeters in length.

The aerosol generating segment preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol generating article. The outer diameter of the aerosol generating segment may range from about 5 millimeters to about 12 millimeters. In one embodiment, the aerosol generating segment may have an outer diameter of approximately 7.2 millimeters.

The aerosol generating article may include a filter plug. The filter plug may be located at the proximal end of the aerosol generating article. The filter plug may be a cellulose acetate filter plug. In some embodiments, the filter plug may have a length of from about 5 millimeters to about 10 millimeters. In some preferred embodiments, the filter plug may be approximately 7 millimeters in length.

The first portion of the current collection system may be configured to heat the first portion of the aerosol-forming substrate. The first portion of the current collection system may be configured to substantially surround the first portion of the aerosol-forming substrate. The second part of the current collecting system may be configured to heat the second part of the aerosol-forming substrate. The second portion of the current collection system may be configured to substantially surround the second portion of the aerosol-forming substrate.

The aerosol generating article may comprise an outer wrapper. The outer wrapper may be made of paper. The outer wrap may be permeable to gas in the aerosol generating segment. Particularly, in embodiments containing a plurality of aerosol-forming substrates, the outer wrap may include perforations or other air inlets at the interface between adjacent aerosol-forming substrates. If a gap is provided between adjacent aerosol-forming substrates, the outer wrap may include perforations or other air inlets at the space. This allows the aerosol-forming substrate to be directly supplied with air that has not been drawn in through another aerosol-forming substrate. This, in turn, allows the amount of air accepted by each aerosol-forming substrate to be increased. This, in turn, makes it possible to improve the characteristics of the aerosol generated from the aerosol-forming substrate.

The aerosol generating article may also include a gap between the aerosol generating substrate and the filter plug. Said gap may have a size of approximately 18 millimeters, but it may also have a size in the range of from about 5 millimeters to about 25 millimeters.

It should also be appreciated that specific combinations of the various features described above may be independently implemented, provided, and used.

Embodiments of the present invention will now be described solely by way of example with reference to the accompanying drawings, in which:

in Fig. 1 is a schematic illustration of a current collecting system according to an embodiment of the present invention placed between a pair of inductors;

in Fig. 2 is a schematic illustration of a current collecting system according to an embodiment of the present invention placed between a pair of inductors;

in Fig. 3 is an exploded perspective view of a susceptor system according to an embodiment of the present invention;

in Fig. 4 is a perspective view of the current collecting system of FIG. 3;

in Fig. 5 is a sectional view of an aerosol generating system according to an embodiment of the present invention, wherein the aerosol generating system includes an aerosol generating article and an aerosol generating device having an induction heating system;

in Fig. 6 is a sectional view of the proximal end of the aerosol generating device of FIG. 5;

in Fig. 7 is a cross-sectional view of the aerosol generating system of FIG. 5, with an aerosol generating article housed in the aerosol generating device;

in Fig. 8 is a schematic illustration of a current collecting system according to an embodiment of the present invention placed between a pair of inductors;

in Fig. 9 is a sectional view of an aerosol generating system according to another embodiment of the present invention, wherein the aerosol generating system includes an aerosol generating article and an aerosol generating device having an induction heating system;

in Fig. 10 shows a graph of temperature versus time for the current collector system of FIG. 8;

in Fig. 11 is an illustrative diagram of an induction heating system;

in Fig. 12 shows an exemplary circuit for driving an induction heating system; And

in Fig. 13 shows exemplary pulse width modulated signals for driving an induction heating system.

In FIG. 1 is a schematic diagram of a current collector system 10 according to an embodiment of the present invention. The current collecting system 10 is an elongated tubular element having a circular cross-section. The pantograph system 10 includes a first pantograph 12, a second pantograph 14, and a space 15 between the first pantograph 12 and the second pantograph 14. The first pantograph 12 and the second pantograph 14 are each an elongated tubular member having a circular cross-section. The first pantograph 12 and the second pantograph 14 are coaxially aligned end to end along the longitudinal axis AA.

The current collector system 10 includes a cylindrical cavity 20 open at both ends and formed by the inner surfaces of the first pantograph 12 and the second pantograph 14. The cavity 20 is configured to receive a portion of a cylindrical aerosol generating article (not shown) containing an aerosol generating substrate such that the outer surface of the the article aerosol may be heated by the first susceptor and the second susceptor, thereby heating the aerosol-forming substrate.

The cavity 20 contains three parts: a first part 22 located at the first end and formed by the inner surface of the tubular first pantograph 12, a second part 24 located at the second end opposite the first end and formed by the inner surface of the tubular second pantograph 14, and an intermediate part 26. limited by the gap 15 between the first pantograph 12 and the second pantograph 14. The first pantograph 12 is configured to heat the first part of the aerosol-generating product located in the first part 22 of the cavity 20, and the second pantograph 14 is configured to heat the second part of the aerosol-generating product located in the second parts 24 cavities 20.

The first inductor 32 is located around the first pantograph 12 and extends substantially the length of the first pantograph 12. Thus, the first pantograph 12 is surrounded by the first inductor 32 for substantially its entire length. When a varying electric current, preferably alternating current, is applied to the first inductor 32, the first inductor 32 generates a varying magnetic field that is concentrated in the first portion 22 of the cavity 20. Such varying magnetic field generated by the first inductor 32 induces eddy currents in the first pantograph 12, causing heating of the first pantograph 12.

The second inductor 34 is located around the second pantograph 14 and extends substantially the length of the second pantograph 14. Thus, the second pantograph 14 is surrounded by the second inductor 34 for substantially its entire length. When a varying electric current, preferably alternating current, is applied to the second inductor 34, the second inductor 34 generates a varying magnetic field concentrated in the second portion 24 of the cavity 20. Such varying magnetic field generated by the second inductor 34 induces eddy currents in the second pantograph. 14, causing heating of the second pantograph 14.

The gap 15 between the first pantograph 12 and the second pantograph 14 provides a space between the first pantograph 12 and the second pantograph 14 that is not subject to induction heating upon application of a varying magnetic field generated by either the first inductor 32 or the second inductor 3 4 . In addition, the gap 15 provides thermal insulation of the second pantograph 14 from the first pantograph 12, so that the amount of heat transfer between the first pantograph 12 and the second pantograph 14 is reduced compared to a pantograph system in which the first pantograph and the second pantograph are placed adjacent to each other in direct thermal contact . Thus, by providing a gap 15 between the first pantograph 12 and the second pantograph 14, it is possible to selectively heat the first part 22 of the cavity 20 by the first pantograph 12 with minimal heating of the second part 24 of the cavity 20, and it is possible to selectively heat the second part 24 of the cavity 20 by the second pantograph 14 with minimal heating of the first part 22 of cavity 20.

The first pantograph 12 and the second pantograph 14 may be heated simultaneously by simultaneously applying varying electrical current, preferably alternating current, to the first inductor 32 and the second inductor 34. Alternatively, the first pantograph 12 and the second pantograph 14 may be heated independently or alternately by applying a varying electrical current, preferably an alternating current, to the first inductor 32 without applying a current to the second inductor 34, and by subsequently applying a varying electrical current, preferably alternating current, to the second inductor 34 without applying current to the first inductor 32. It is also contemplated that a varying electric current, preferably an alternating current, may be supplied to the first inductor 32 and the second inductor 34 in series.

In FIG. 2 is a schematic illustration of a current collecting system according to another embodiment of the present invention. The current collecting system shown in FIG. 2 is almost identical to the current collecting system shown in FIG. 1, and like reference numerals are used to designate like elements.

Current collecting system 10 according to FIG. 2 is an elongated tubular element having a circular cross section. The pantograph system 10 includes a first pantograph 12 and a second pantograph 14. The difference between the pantograph system 10 of FIG. 1 and current collecting system 10 according to FIG. 2 is that the current collecting system 10 according to FIG. 2 includes an intermediate element 16 placed between the first pantograph 12 and the second pantograph 14. In the embodiment of FIG. 2, there is also a gap between the first pantograph 12 and the second pantograph 14, but this gap is filled by an intermediate member 16. In this embodiment, the intermediate member 16 is attached to the end of the first pantograph 12, and it is also attached to the end of the second pantograph 14. As a result of attaching the intermediate member 16 to the end of the first pantograph 12 and attaching the intermediate member 16 to the end of the second pantograph 14, the first pantograph 12 is indirectly connected to the second pantograph 14. By indirectly attaching the first pantograph 12 to the second pantograph 14, the advantage of being able to form an integral pantograph system is provided.

The intermediate element 16 contains thermal insulation material. The thermal insulation material is also electrical insulating. In this embodiment, the intermediate element 16 is made of a polymeric material such as PEEK. Thus, the intermediate element 16 between the first pantograph 12 and the second pantograph 14 provides a space between the first pantograph 12 and the second pantograph 14 that is not subject to inductive heating upon application of a varying magnetic field generated by either the first inductor 32 or the second inductor 34. In addition, the intermediate element 16 provides thermal insulation of the second pantograph 14 from the first pantograph 12, so that the amount of heat transfer between the first pantograph 12 and the second pantograph 14 is reduced compared to a pantograph system in which the first pantograph and the second pantograph are placed adjacent to each other in direct thermal contact. The spacer 16 may also further reduce the amount of heat transfer between the first pantograph 12 and the second pantograph 14 compared to the gap 15 of the pantograph system 10 of FIG. 1. As a result, the intermediate element 16 between the first pantograph 12 and the second pantograph 14 allows the first part 22 of the cavity 20 to be selectively heated by the first pantograph 12 while minimally heating the second part 24 of the cavity 20, and it allows the second part 24 of the cavity 20 to be selectively heated by the second pantograph 14 with minimal heating of the first part 22 of cavity 20.

In FIG. 3-7 are schematic illustrations of an aerosol generating system according to one embodiment of the present invention. The aerosol generating system includes an aerosol generating device 100 and an aerosol generating article 200. The aerosol generating device 100 includes an induction heating system 110 according to the present invention. The induction heating system 110 includes a current collecting system 120 according to the present invention.

In FIG. 3 and 4 show schematic illustrations of a pantograph system 120. The pantograph system 120 includes a first pantograph 122, a second pantograph 124, a third pantograph 126, a first intermediate member 128, and a second intermediate member 130. The first intermediate member 128 is positioned between the first pantograph 122 and the second pantograph 124. The second intermediate element 130 is located between the second pantograph 124 and the third pantograph 126.

In this embodiment, each of the first pantograph 122, the second pantograph 124, and the third pantograph 126 is identical to the others. Each of the pantographs 122, 124, 126 is an elongated tubular pantograph defining an internal cavity. Each pantograph and its corresponding internal cavity are substantially cylindrical and have a circular cross-section that is constant along the length of the pantograph. The internal cavity of the first pantograph 122 defines a first region 134. The internal cavity of the second pantograph 124 defines a second region 136. The internal cavity of the third pantograph defines a third region 138.

Likewise, the first intermediate element 128 and the second intermediate element 130 are identical. The intermediate elements 128, 130 are tubular and form an internal cavity. Each intermediate element 128, 130 is substantially cylindrical and has a circular cross-section that is constant along the length of the intermediate element. The outer diameter of the intermediate members 128, 130 is equal to the outer diameter of the pantographs 122, 124, 126, so that the outer surface of the intermediate members 128, 130 can be aligned flush with the outer surface of the pantographs 122, 124, 126. The inner diameter of the intermediate members 128, 130 is also equal to the inner diameter diameter of pantographs 122, 124, 126 such that the inner surface of the intermediate members 128, 138 can be flush with the inner surface of pantographs 122, 124, 126.

The first pantograph 122, the first intermediate member 128, the second pantograph 124, the second intermediate member 130, and the third pantograph 126 are arranged end to end and coaxially aligned along the B-B axis. In this arrangement, the pantographs 122, 124, 126 and intermediate members 128, 130 form a tubular elongated cylindrical structure. This structure forms the current collector system 120 according to an embodiment of the present invention.

The elongated tubular susceptor system 120 includes an internal cavity 140. The susceptor system cavity 140 is formed by the internal cavities of the susceptors 122, 124, 126 and the internal cavities of the intermediate elements 128, 130. The susceptor system cavity 140 is configured to receive an aerosol-generating segment generating an aerosol of the product 200, as described in more detail below.

The intermediate elements 128, 130 are made of electrical insulating and thermal insulating material. Thus, the pantographs 122, 124, 126 are substantially isolated from each other electrically and thermally. The material of the intermediate members 128, 130 is also substantially gas impermeable. In this embodiment, the tubular susceptor system 120 is substantially gas-tight in the direction from the outer surface to the inner surface defining the susceptor system cavity 140.

In FIG. 5, 6 and 7 show schematic cross-sections of an aerosol generating device 100 and an aerosol generating article 200.

The aerosol generating device 100 includes a generally cylindrical device housing 102, with a shape and size similar to a traditional cigarette. The device body 102 defines a device cavity 104 at the proximal end. The device cavity 104 is substantially cylindrical, open at the proximal end and substantially closed at the distal end opposite the proximal end. The device cavity 104 is configured to receive an aerosol generating segment 210 of the aerosol generating article 200. Accordingly, the length and diameter of the device cavity 104 is substantially similar to the length and diameter of the aerosol generating segment 210 of the aerosol generating article 200.

The aerosol generating device 100 further includes a power source 106 in the form of a rechargeable nickel-cadmium battery, a controller 108 in the form of a printed circuit board containing a microprocessor, an electrical connector 109, and an induction heating system 110. All of the power source 106, the controller 108, and the induction heating system 110 are housed There are 102 devices inside the casing. The induction heating system 110 of the aerosol generating device 100 is located at the proximal end of the device 100 and is generally located around the cavity 104 of the device. An electrical connector 109 is located at the distal end of the device housing 109 opposite the device cavity 104.

The controller 108 is configured to control the supply of power from a power source 106 to the induction heating system 110. The controller 108 further includes an inverter for converting direct current to alternating current, containing a Class D power amplifier and configured to supply varying current, preferably alternating current, to the induction heating system. heating system 110. Additionally or alternatively, the DC to AC inverter may comprise at least one of a Class C and a Class E power amplifier. The controller 108 is also configured to control recharging of the power source 106 from the electrical connector 109. In addition, the controller 108 includes a puff sensor (not shown) configured to detect a user taking puffs on an aerosol generating article located in the device cavity 104.

The induction heating system 110 includes three induction heating blocks, including a first induction heating block 112, a second induction heating block 114, and a third induction heating block 116. The first induction heating block 112, the second induction heating block 114, and the third induction heating block 116 are substantially identical.

The first induction heating unit 112 includes a cylindrical tubular first inductor coil 150, a cylindrical tubular first flux concentrator 152 disposed around the first inductor coil 150, and a cylindrical tubular first induction unit housing 154 disposed around the first flux concentrator 152.

The second induction heating unit 114 includes a cylindrical tubular second inductor coil 160, a cylindrical tubular second flux concentrator 162 disposed around the second inductor coil 160, and a cylindrical tubular second induction unit housing 164 disposed around the second flux concentrator 162.

The third induction heating unit 116 includes a cylindrical tubular third inductor coil 1 70, a cylindrical tubular third flux concentrator 172 disposed around the third inductor coil 170, and a cylindrical tubular third induction unit housing 174 disposed around the third flux concentrator 172.

Accordingly, each induction heating block 112, 114, 116 is a substantially tubular block with a circular cross-section. In each induction heating block 112, 114, 116, a flux concentrator extends over the proximal and distal ends of the inductor so that the inductor is located within the annular cavity of the flux concentrator. Likewise, the housing of each induction heating block extends over the proximal and distal ends of the flux concentrator such that the flux concentrator and inductor are housed within the annular cavity of the induction heating block housing. This system allows the flux concentrator to concentrate the magnetic field generated by the inductor into the internal cavity of the inductor. This system also allows the induction unit housing to contain the flux concentrator and inductor within the induction unit housing.

The induction heating device 110 further includes a susceptor system 120. The susceptor system 120 is located around the inner surface of the device cavity 104. In this embodiment, the device housing 102 defines the inner surface of the device cavity 104. However, it is contemplated that in some embodiments, the interior surface of the device cavity is formed by the interior surface of the current collector system 120.

Induction heating blocks 112, 114, 116 are located around the susceptor system 120 such that the susceptor system 120 and the induction heating blocks 112, 114, 116 are concentrically located around the device cavity 104. The first induction heating block 112 is located around the first pantograph 122 at the distal end of the device cavity 104. A second induction heating block 114 is located around a second susceptor 124 in the central portion of the device cavity 104. A third induction heating block 116 is located around a third pantograph 126 at the proximal end of the device cavity 104. It is contemplated that in some embodiments, the flux concentrators may also extend within the intermediate elements of the current collector system to further deform the magnetic fields generated by the inductors in the direction of the current collectors.

The first inductor 150 is connected to the controller 108 and the power supply 106, and the controller 108 is configured to supply varying electrical current, preferably alternating current, to the first inductor 150. When a varying electric current, preferably alternating current, is applied to the first inductor 150, the first inductor 150 generates a varying magnetic field that heats the first pantograph 122 by induction.

The second inductor 160 is coupled to the controller 108 and the power supply 106, and the controller 108 is configured to supply varying electrical current, preferably alternating current, to the second inductor 160. By applying a varying electric current, preferably alternating current, to the second inductor 160, the second inductor 160 generates a varying magnetic field that heats the second pantograph 12 4 by induction.

The first inductor 170 is connected to the controller 108 and the power supply 106, and the controller 108 is configured to supply varying electrical current, preferably alternating current, to the third inductor 170. By applying a varying electric current, preferably alternating current, to the third inductor 170, the third inductor 170 generates a varying magnetic field that heats the third pantograph 126 by induction.

The device housing 102 also defines an air inlet 180 in the vicinity of the distal end of the device cavity 106. The air inlet 180 is configured to draw ambient air into the device housing 102. An air flow path 181 is formed through the device between the air inlet 180 and the air outlet at the distal end of the device cavity 104 to allow air to be drawn from the air inlet 180 into the device cavity 104.

The aerosol generating article 200 generally has the shape of a cylindrical rod with a diameter similar to the internal diameter of the cavity 104 of the device. The aerosol generating article 200 includes a cylindrical cellulose acetate filter plug 204 and a cylindrical aerosol generating segment 210 wrapped together with an outer wrapper 220 of cigarette paper.

The filter plug 204 is located at the proximal end of the aerosol generating article 200 and forms the mouthpiece of the aerosol generating system upon which the user puffs to receive the aerosol generated by the system.

The aerosol generating segment 210 is located at the distal end of the aerosol generating article 200 and has a length substantially equal to the length of the cavity 104 of the device. The aerosol-generating segment 210 contains a plurality of aerosol-forming substrates, including: a first aerosol-forming substrate 212 located at the distal end of the aerosol-generating article 200, a second aerosol-forming substrate 214 located adjacent to the first aerosol-forming substrate 212, and a third aerosol-forming substrate 216 located at the proximal end of the aerosol-generating segment 210 adjacent to the second aerosol-forming substrate 216. It should be understood that in some embodiments, two or more aerosol-forming substrates may be made of the same materials. However, in this embodiment, each of the aerosol-forming substrates 212, 214, 216 is different from the others. The first aerosol-forming substrate 212 contains a collected and corrugated sheet of homogenized tobacco material without additional flavoring agents. The second aerosol-forming substrate 214 comprises an assembled and corrugated sheet of homogenized tobacco material containing a menthol flavoring agent. The third aerosol-forming substrate contains a flavoring agent in the form of menthol and does not contain tobacco material or any other source of nicotine. Each of the aerosol-forming substrates 212, 214, 216 also contains additional components, such as one or more aerosol-forming agents and water, such that heating the aerosol-forming substrate results in the generation of an aerosol with the desired organoleptic properties.

The proximal end of the first aerosol-forming substrate 212 is open because it is not covered by the outer wrap 220. In this embodiment, it is possible for air to be drawn into the aerosol-generating segment 210 through the proximal end of the first aerosol-forming substrate 212 at the proximal end of the article 200.

In this embodiment, the first aerosol-forming substrate 212, the second aerosol-forming substrate 214, and the third aerosol-forming substrate 216 are arranged end to end. However, it is contemplated that in other embodiments, a gap may be provided between the first aerosol-forming substrate and the second aerosol-forming substrate, and a gap may be provided between the second aerosol-forming substrate and the third aerosol-forming substrate.

As shown in FIG. 7, the length of the first aerosol-forming substrate 212 is such that when the aerosol-generating segment 210 of the aerosol-generating article 200 is placed in the device cavity 104, the first aerosol-forming substrate 212 extends from the distal end of the device cavity 104 through the first region 134 of the first pantograph 122 to the first intermediate element 128 The length of the second aerosol-forming substrate 214 is such that the second aerosol-forming substrate 214 extends from the first intermediate element 128 through the second region 136 of the second pantograph 124 to the second intermediate element 130. The length of the third aerosol-forming substrate 216 is such that the third aerosol-forming substrate. 216 extends from the second intermediate member 130 to the proximal end of the device cavity 104.

In use, when the aerosol generating article 200 is placed in the device cavity 104, the user can puff at the proximal end of the aerosol generating article 200 to inhale the aerosol generated by the aerosol generating system. When a user takes a puff at the proximal end of the aerosol generating article 200, air is drawn into the device body 102 through the air inlet 180 and is drawn along the air flow path 181 into the device cavity 104. Air is drawn into the aerosol generating article 200 at the proximal end of the first aerosol-forming substrate 212 through an outlet at the distal end of the device cavity 104.

In this embodiment, the controller 108 of the aerosol generating device 100 is configured to supply power to the inductors of the induction heating system 110 in a predetermined sequence. Said predetermined sequence comprises applying a varying electrical current, preferably alternating current, to the first inductor 150 during the user's first tightening, then applying a varying electrical current, preferably alternating current, to the second inductor 160 during the user's second tightening after the first tightening has been validated. , and then applying a varying electrical current, preferably alternating current, to the third inductor 170 during a third puff by the user after completion of the second puff. On the fourth puff, this sequence resumes with the first inductor 150. This sequence results in heating of the first aerosol-forming substrate 212 on the first puff, heating of the second aerosol-forming substrate 214 on the second puff, and heating of the third aerosol-forming substrate 216 on the third puff. Since the aerosol-forming substrates 212, 214, 216 of the article 100 are all different, this sequence results in a different user experience with each puff of the aerosol-generating system.

It should be understood that the controller 108 may be configured to supply power to the inductors in a different sequence or simultaneously, depending on the desired delivery of the aerosol to the user. In some embodiments, the user has the ability to control the aerosol generating device to change the specified sequence.

In FIG. 8 is a schematic illustration of a current collector system 310 according to an embodiment of the present invention. The current collector system 310 is an elongated tubular member having a circular cross section. The current collector system 310 includes one elongated pantograph having a first portion 312 and a second portion 314. The first portion 312 and the second portion 314 are each an elongate tubular member having a circular cross-section. The first portion 312 and the second portion 314 are coaxially aligned end to end along the longitudinal axis AA.

The current receiving system 310 includes a cylindrical cavity 320 open at both ends and formed by the inner surfaces of the first part 312 and the second part 314. The cavity 320 is configured to receive a portion of a cylindrical aerosol generating article (not shown) containing an aerosol generating substrate such that the outer surface of the aerosol generating the article aerosol may be heated by the first susceptor and the second susceptor, thereby heating the aerosol-forming substrate.

Cavity 320 is configured to receive a portion of an aerosol-generating article containing an aerosol-forming substrate.

The cavity 320 contains two parts, namely a first part 322 located at the first end and formed by the inner surface of the first part 312 of the current collector system 310, and a second part 324 located at the second end opposite the first end and formed by the inner surface of the second part 314 of the current collector system 310. The first part 312 of the susceptor system 310 is configured to heat the first part of the aerosol generating article housed in the first part 322 of the cavity 320, and the second part 314 of the susceptor system 310 is configured to heat the second part of the aerosol generating article housed in the second part 324 of the cavity 320 .

The first inductor 332 is disposed around the first portion 312 of the current collector system 310 and extends substantially the length of the first portion 312 of the current collector system 310. Thus, the first portion 312 of the current collector system 310 is surrounded by the first inductor 332 substantially along its entire length. When a varying electric current, preferably alternating current, is applied to the first inductor 332, the first inductor 332 generates a varying magnetic field concentrated in the first portion 322 of the cavity 320. Such varying magnetic field generated by the first inductor 332 induces eddy currents in the first portion 312 of the current collector system 310, causing the first portion 312 of the current collector system 310 to heat up.

A second inductor 334 is positioned around the second portion 314 of the current collector system 310 and extends substantially the length of the second portion 314 of the current collector system 310. Thus, the second portion 314 of the current collector system 310 is surrounded by the second inductor 334 of the current collector system 310 for substantially its entire length. When a varying electric current, preferably alternating current, is applied to the second inductor 334, the second inductor 334 generates a varying magnetic field concentrated in the second portion 324 of the cavity 320. Such varying magnetic field generated by the second inductor 334 induces eddy currents in the second portion 314 of the current collector system 310, causing said second portion 314 to heat up.

The first portion 312 of the current collector system 310 and the second portion 314 of the current collector system 310 may be heated simultaneously by simultaneously applying varying electrical current, preferably alternating current, to the first inductor 332 and the second inductor 334. Alternatively, the first portion 312 of the current collector system 310 and the second portion 314 of the current collector system 310 may be heated independently or alternately by applying varying electrical current, preferably alternating current, to the first inductor 332 without applying current to the second inductor 334, and then applying varying electrical current, preferably alternating current, to the second inductor 334 without supplying current to the first inductor 332. It is also provided that a varying electrical current, preferably alternating current, can be supplied to the first inductor 332 and the second inductor 334 in series.

Temperature sensors in the form of thermocouples are also provided on the outer surfaces of the current collector system 310. A first thermocouple 342 is provided on an outer surface of a first portion 312 of a current collector system 310 for measuring the temperature of a first portion 312 of a current collector system 310. A second thermocouple 344 is provided on an outer surface of a second portion 314 of a current collector system 310 for measuring a temperature of a second portion 314 of a current collector system 310.

In FIG. 9 is a cross-sectional view of an aerosol generating system 600 in accordance with yet another embodiment of the present invention. The aerosol generating system 600 includes an aerosol generating device 602 including a current collector system 310, a first inductor 332, and a second inductor 334 of FIG. 8. Aerosol generating device 602 is similar to aerosol generating device 100 in FIG. 5, and like reference numerals are used to designate like parts.

The aerosol-generating system 60 0 also includes an aerosol-generating article 700. The aerosol-generating article 700 includes an aerosol-forming substrate 702 having the shape of a cylindrical rod and containing tobacco strands made from homogenized tobacco and an aerosol-forming agent. The cylindrical rod of aerosol-forming substrate 702 has a length substantially equal to the length of the cavity 104 of the device. The aerosol generating article 700 also includes a tubular cooling segment 704, a filter segment 706, and a mouthpiece end segment 708. The aerosol-forming substrate 702, tubular cooling segment 704, filter segment 706, and mouthpiece segment 708 are held together by an outer wrap 710.

In one example, the aerosol-forming substrate 702 has a length from 34 millimeters to 50 millimeters, more preferably, the aerosol-forming substrate 702 has a length from 38 millimeters to 46 millimeters, and even more preferably, the aerosol-forming substrate 702 has a length of 42 millimeters.

In one example, the overall length of the article 700 is from 71 millimeters to 95 millimeters, more preferably the overall length of the article 700 is from 79 millimeters to 8-7 millimeters, and even more preferably the overall length of the article 700 is 83 millimeters.

In one example, the cooling segment 704 is an annular tube, and an air gap is formed within the cooling segment 704. This air gap provides a chamber for the flow of heated vaporized components generated from the aerosol-forming substrate 702. The cooling segment 704 is hollow to provide a chamber for aerosol accumulation, but is nevertheless rigid enough to withstand the axial compressive forces and bending moments that may occur during during production and, when using article 700, during insertion into aerosol generating device 602. In one example, the wall thickness of cooling segment 704 is approximately 0.29 millimeters.

Cooling segment 704 provides physical displacement between aerosol-forming substrate 702 and filter segment 706. The physical displacement provided by cooling segment 704 creates a temperature gradient along the length of cooling segment 704 during use. In one example, cooling segment 704 is configured to provide a temperature difference of at least 40 degrees Celsius between the heated vaporized component entering the distal end of the cooling segment 704 and the heated vaporized component exiting the proximal end of the cooling segment 704. In one example, example, the cooling segment 704 is configured to provide a temperature difference of at least 60 degrees Celsius between the heated vaporized component entering the distal end of the cooling segment 704 and the heated vaporized component exiting the proximal end of the cooling segment 704. The length of the cooling element 704 protects the temperature-sensitive filter segment 706 from the high temperatures of the aerosol generated from the aerosol-forming substrate 702.

In one example, the length of the cooling segment 704 is at least 15 millimeters. In one example, the length of the cooling segment 704 is from 20 millimeters to 30 millimeters, more specifically from 23 millimeters to 27 millimeters, more specifically from 25 millimeters to 27 millimeters, and more particularly from 25 millimeters.

The cooling segment 704 is made of paper. In one example, the cooling segment 704 is made of a spirally wound paper tube that forms a hollow inner chamber but still retains mechanical rigidity. Spiral wound paper tubes are capable of meeting the stringent dimensional accuracy requirements of high-speed manufacturing processes in terms of tube length, outside diameter, roundness and straightness. In yet another example, the cooling segment 704 is a recess formed by rigid ficell or tipping paper. The rigid ficella or tipping paper is manufactured such that it has sufficient rigidity to withstand the axial compressive forces and bending moments that may be encountered during manufacture and, in use of the article 700, during insertion into the aerosol generating device 602.

For each of the examples of cooling segment 704, the dimensional accuracy of the cooling segment is sufficient to meet the dimensional accuracy requirements of a high-speed manufacturing process.

The filter segment 706 may be made of any filter material sufficient to remove one or more volatile compounds from the heated vaporized components coming from the aerosol-forming substrate 702. In one example, the filter segment 706 is made of a monoacetate material, such as cellulose acetate. The filter segment 706 provides cooling and reduced irritation from heated vaporized components without reducing the amount of heated vaporized components to a level that is unsatisfactory for the user.

The density of the cellulose acetate tow material of the filter segment 706 determines the pressure drop within the filter segment 706, which in turn determines the draw resistance of the article 700. Therefore, the selection of the material of the filter segment 706 is important in controlling the draw resistance of the article 700. In addition, the filter segment performs the function filtration in product 700.

The presence of the filter segment 706 provides an insulating effect by providing additional cooling to the heated evaporated components that exit the cooling segment 704. This additional cooling effect reduces the temperature when the user's lips contact the surface of the filter segment 706.

One or more flavors may be added to filter segment 706 either by directly injecting flavor liquids into filter segment 706 or by embedding or placing one or more erodible flavor capsules or other flavor carriers within the cellulose acetate tow of filter segment 706. In one example, the filter segment 706 has a length of from 6 millimeters to 10 millimeters, more preferably 8 millimeters.

The mouth end segment 708 is an annular tube, and an air gap is formed within the mouth end segment 708. This air gap provides a chamber for the heated vaporized components that flow from the filter segment 706. The mouthpiece end segment 708 is hollow to provide a chamber for aerosol accumulation, but is rigid enough to withstand the axial compressive forces and bending moments that may occur during time of manufacture and, during use of the product, during insertion into the aerosol generating device 602. In one example, the wall thickness of the mouthpiece end segment 708 is approximately 0.2-9 millimeters.

In one example, the length of the mouth end segment 708 is from 6 millimeters to 10 millimeters, and more preferably 8 millimeters.

The mouth end segment 708 may be made of a spiral wound paper tube that provides a hollow inner chamber while still maintaining critical mechanical rigidity. Spiral wound paper tubes are capable of meeting the stringent dimensional accuracy requirements of high-speed manufacturing processes in terms of tube length, outside diameter, roundness and straightness.

The mouthpiece end segment 708 provides the function of preventing any liquid condensate that accumulates at the outlet of the filter segment 706 from coming into direct contact with the user.

It should be understood that, in one example, the mouth end segment 708 and the cooling segment 704 may be formed from a single tube, and the filter segment 70 6 may be located within the tube, separating the mouth end segment 708 and the cooling segment 704.

Ventilation openings 707 are located within the cooling segment 704 to assist in cooling the article 700. In one example, the venting holes 707 include one or more rows of holes, and preferably, each row of holes is located circumferentially around the article 700 in a section that is substantially perpendicular to the longitudinal axis of the article. 700.

In one example, one to four rows of vents 707 are provided to provide ventilation for article 700. Each row of vents 707 may have from 12 to 36 vents 707. The vents 707 may have a diameter, for example, from 100 to 500 micrometers. In one example, the axial spacing between rows of vent holes 707 is from 0.25 millimeters to 0.75 millimeters; more preferably, the axial spacing between the rows of vent holes 707 is 0.5 millimeters.

In one example, the vent holes 707 are the same size. In yet another example, the vents 707 vary in size. The vents 707 may be made using any suitable technology, such as one or more of the following technologies: laser technology, mechanical perforation of the cooling segment 704, or pre-punching the cooling segment 704 prior to its inclusion in the product 700. The vents 707 are located such that they provide efficient cooling for the 700 product.

In one example, the rows of vent holes 707 are located at least 11 millimeters from the proximal end of the article 700 and, more preferably, the vent holes 707 are located at a distance from 17 millimeters to 20 millimeters from the proximal end of the article 700. The location of the vent holes 707 is selected such that that the user does not block the ventilation openings 707 when using the product 700.

By providing rows of vent holes 707 spaced from 17 millimeters to 20 mm from the proximal end of the article 700, the advantage is provided that the vent holes 707 can be positioned outside the aerosol generating device 602 when the article 700 is fully inserted into the aerosol generating device 602. By positioning the vents openings 707 on the outside of the device 602, allow unheated air to enter the product 700 through the vents 707 from the outside of the device 602 to assist in cooling the product 700.

In FIG. 10 shows graphs of temperature 404 versus time 402 during one heating cycle, with the first portion 312 of the current collector system 310 plotted using readings from the first thermocouple 342 and the second portion of the susceptor system 310 plotted using readings from the second thermocouple 344 .In Fig. 10, a temperature graph of the first portion 312 of the current collector system 310 using readings from the first thermocouple 342 is shown as a solid line 406. In FIG. 10, a temperature plot of the second portion 314 of the current collector system 310 using readings from the second thermocouple 344 is shown as a dotted line 408.

As shown in FIG. 10, once heating begins, the first portion 312 of the current collector system 310 heats up rapidly during the first step 410 and reaches operating temperature after the first period 414 of approximately 60 seconds. The second portion 314 of the current collector system 310 also heats up during the first stage 410, but much more slowly than the first portion 312. The temperature of the first portion 312 of the current collector system 310 exceeds the temperature of the second portion 314 of the current collector system 310 throughout the first stage 410. The second portion 314 of the current collector system 310 310 does not reach the operating temperature during the first step 410. In this embodiment, by operating temperature is meant the desired temperature at which the most desirable aerosol is released from the aerosol-forming substrate.

Next, as shown in FIG. 10, after a second period 416 of approximately 150 seconds from the start of heating, the first step 410 ends and the second step 412 begins. In the second step 412, the first portion 312 of the current collector system 312 is heated to a lower temperature, but still within approximately 50 degrees Celsius relative to operating temperature. Also in the second step 412, the second portion 314 of the susceptor system 310 is rapidly heated to operating temperature and reaches operating temperature after a third period 418 of approximately 210 seconds from the start of heating.

In particular, in FIG. 10 shows a desired temperature profile for an aerosol generating system, with a first portion 312 of the susceptor system 310 configured to heat a proximal portion of the aerosol-forming substrate and a second portion 314 of the susceptor system 310 configured to heat a distal portion of the aerosol-forming substrate. The proximal portion of the aerosol-forming substrate is located toward the mouthpiece end of the aerosol-generating article containing the aerosol-forming substrate. This temperature profile within the aerosol-forming substrate allows the generation of an aerosol with the desired characteristics throughout the extended period of aerosol generation. Heating the proximal portion of the aerosol-generating substrate before heating the distal portion of the substrate promotes optimal delivery of the generated aerosol to the user. In particular, this is believed to be due to the fact that the hot aerosol from the heated proximal portion of the aerosol-forming substrate does not interact with the unheated distal portion of the aerosol-forming substrate during the first stage, and therefore the hot aerosol from the proximal portion does not contain the volatile compounds released from the distal portion. parts.

Such a temperature profile can be achieved by exciting varying currents, preferably alternating currents, in the first inductor 312 and the second inductor 314 in various ways. For example, in a first step, a first varying current, preferably an alternating current, may be driven in the first inductor 312 at a first duty cycle, and a second varying current, preferably an alternating current, may be driven in the second inductor 314, with a duty cycle of the second varying current being less than the duty cycle of the first varying current such that the current driven in the first inductor 312 exceeds the current driven in the second inductor 314 during the first step. It should be understood that in some embodiments, the varying current is not applied to the second inductor 314 in the first step 410. In the second step, the opposite may be applied such that the duty cycle of the first varying current is less than the duty cycle of the second pulse width modulated alternating signal.

In FIG. 11 illustrates a current collector system 501. The induction heating system 501 includes a first LC circuit 510. The first LC circuit 510 includes a first inductor 512 and a first capacitor 514. The first inductor 512 has a first inductor. The first capacitor 514 has a first capacitance. The resonant frequency of the first LC circuit 510 is determined by the first inductance and the first capacitance.

In FIG. 11 further shows a first transistor 516, such as a field effect transistor, coupled to the first LC circuit 510. In addition, FIG. 11 shows DC power supply terminals 518. The DC power supply terminals 518 are connected to a power source, preferably a battery, of the device. The first LC circuit 510 is configured to inductively heat the first portion of the current collector system. The first part of the susceptor system may be located adjacent to the first inductor such that the first inductor can heat the first part of the susceptor element due to eddy currents and/or hysteresis.

The induction heating system 501 of FIG. 11 also includes a second LC circuit 520 including a second inductor 522 and a second capacitor 524. Connected to the second LC circuit 520 is a second transistor 526.

The first transistor 516 is configured to control the operation of the first LC circuit 510. The second transistor 526 is configured to control the operation of the second LC circuit 520.

Components of the second LC circuit 520 may be similar to those of the first LC circuit 510. That is, the second inductor 522 may have a second inductance, the second capacitor 524 may have a second capacitance, and the second transistor 526 may be a field effect transistor. Two LC circuits 510, 520 may be connected in parallel with a DC power supply.

In FIG. 12 shows a controller 527, in addition to a power stage 528. The power stage 528 may include a first LC circuit 510 and a first transistor 516, as shown in FIG. 11. Power stage 528 may alternatively include all of the components shown in FIG. 11. Controller 527 shown in FIG. 12 may include an oscillator 530. The oscillator 530 may be coupled to one or both of the first transistor 516 and the second transistor 526. In addition, in FIG. 12 also shows a DC power supply 532. A DC power supply 532 may be used to power the elements shown in FIG. 11. In addition, DC power supply 532 may be used to power controller 527, preferably oscillator 530.

The controller 527 further includes a pulse width modulation module 534. Pulse width modulation module 534 may be configured to modulate a signal used to drive LC circuits 510, 520. Controller 527 may be configured to drive LC circuits 510, 520. In other words, controller 527 may be configured to supply electrical signal on the LC circuit 510, 520.

The controller 527 may be configured to drive the first LC circuit 510 using an alternating current of a first frequency. The first frequency may correspond to a resonant frequency of the first LC circuit 510. The controller 527 may be configured to drive the second LC circuit 520 using an alternating current of a second frequency. The second frequency may correspond to the resonant frequency of the second LC circuit 520.

The resonant frequency of the first LC circuit 510 may be equal to the resonant frequency of the second LC circuit 520. In this embodiment, the controller 52 7 may be configured to supply an alternating current with a frequency corresponding to the resonant frequency of the first LC circuit 510 to the first LC circuit 510 during the first stage. The first step may be a step in which advantageously the first part of the aerosol-forming substrate is to be heated by the first part of the current collecting system. The controller 527 may be configured, during the first step, to apply an alternating current at a frequency different from the resonant frequency of the second LC circuit 520 to the second LC circuit 520. Consequently, the second LC circuit 520 will be heated to a lower temperature, than the first LC circuit 510. In a second stage, in which preferably the second part of the aerosol-forming substrate is to be heated by the second part of the current collector system, it is possible for complementary alternating currents to be supplied by the controller to the LC circuits 510, 520. In the second stage, to the second LC circuit 520 an alternating current may be supplied corresponding to a resonant frequency of the second LC circuit 520, and an alternating current at a frequency different from the resonant frequency of the first LC circuit 510 may be supplied to the first LC circuit 510.

The resonant frequency of the first LC circuit 510 may be different from the resonant frequency of the second LC circuit 520. In this case, the controller 527 may be configured, during the first step, to apply alternating current to the first LC circuit 510 at a frequency corresponding to the resonant frequency of the first LC circuits 510. The second LC circuit 520 may be supplied with alternating current at the same frequency. Because the resonant frequency of the second LC circuit 520 is different from the resonant frequency of the first LC circuit 510, the second LC circuit 520 can heat only the second part of the current collector system to a lower temperature than that to which the first LC circuit 510 heats the first part of the current collection system. The controller 52 7 may be configured, in a second step that requires heating of the second portion of the susceptor system, to supply alternating current at a frequency corresponding to the resonant frequency of the second LC circuit 520, while this alternating current will result in lower heating the first part of the current collecting system via the first LC circuit 510.

In FIG. 13 shows an embodiment in which the first LC circuit 510 is predominantly heated in the first step, while the second LC circuit 520 is heated to a lower temperature during the first step. The opposite of this occurs in the second stage, in which the first LC circuit 510 is heated to a lower temperature than the second LC circuit 520. Pulse width modulation is used to facilitate this. More specifically, in the upper part of FIG. 13 shows the complementary duty cycles of a first pulse-width modulated ac signal (top left) and a second pulse-width modulated ac signal (top right). The first pulse width modulated variable signal will be referred to herein as first signal 536. The second pulse width modulated variable signal will be referred to herein as second signal 538. Duty duty refers to the percentage of time the corresponding signal is applied. As can be seen in FIG. 13, the first signal 536 has a high duty cycle of approximately 80%, while the second signal 538 has a low duty cycle of approximately 20%. The embodiment shown in FIG. 13 corresponds to a first stage in which the first portion 541 of the current collector system 540 is predominantly heated, while the second portion 542 of the current collector system 540 is heated to a lower temperature. Below the signals shown in Fig. 13, a first inductor 512 and a second inductor 522 are shown. Below the inductors 512, 522, a susceptor system 540 is depicted, comprising a first portion 541 and a second portion 542. Below the susceptor system 540, an aerosol generating article 542 is depicted containing an aerosol-forming substrate. Below the aerosol generating article 542 is a chart 544 showing heating versus distance. The heating is strong predominantly in the first part 541 of the current collector system 540, while in the second part 542 of the current collecting system 540 the heating is weaker. During the second stage, the heating of the current collector system 540 will be different. During the second stage, the second LC circuit 520 will heat the second portion 542 of the current collector system 540 to a higher temperature, and the temperature of the first portion 541 of the current collector system 540 will be lower than in the first stage. To facilitate this, pulse width modulation can be used, similar to the first stage. The duty cycle of the second signal 538 may be increased while the duty cycle of the first signal 53 6 may be decreased. The temperature can change smoothly from the first stage to the second stage. The duty cycle of the first signal 536 and the duty cycle of the second signal 538 may be up to 100%. Alternatively, the duty cycle of the first signal 536 and the duty cycle of the second signal 538 may be less than 100%. For example, in a first step, the duty cycle of the first signal 53 6 may be greater than 50%, such as 80%, and the duty cycle of the second signal 538 may be close to 0% or 0%; and the opposite of this occurs during the second stage.

It should be understood that the embodiments described above are only specific examples, and other embodiments are contemplated according to the present invention.

Claims (43)

1. An aerosol generating device containing: an induction heating system configured to heat an aerosol-forming substrate and comprising: a current-receiving system that is configured to be heated by a penetrating varying magnetic field to heat the aerosol-forming substrate; at least a first inductor; at least a second inductor; And controller, wherein the controller is configured to excite the first inductor using the first pulse-width modulated alternating signal to generate a first alternating magnetic field for heating the first portion of the current collector system, the controller is configured to drive the second inductor with a second pulse-width modulated alternating signal to generate a second alternating magnetic field for heating the second portion of the current collector system, and the controller is configured to supply a first pulse-width modulated alternating signal and a second pulse-width modulated alternating signal with complementary duty cycles. 2. The aerosol generating device of claim 1, wherein the controller is configured to apply a first pulse width modulated alternating signal to the first inductor during a first step to increase the temperature of the first portion of the current collector system from an initial temperature to a first operating temperature, wherein the controller configured to supply the first pulse width modulated alternating signal during the first stage with a duty cycle greater than 50%, preferably greater than 60%, preferably greater than 70%, more preferably greater than 80%, and most preferably greater than 90%. 3. The aerosol generating device of claim 2, wherein the controller is configured to apply a first pulse width modulated alternating signal to the first inductor during a second step to reduce the temperature of the first portion of the susceptor system from the first operating temperature to the second operating temperature, wherein the controller is configured to supply the first pulse width modulated alternating signal during the second stage with a duty cycle below 50%, preferably below 40%, preferably below 30%, more preferably below 20% and most preferably below 10%. 4. The aerosol generating device according to claim 2 or 3, wherein the controller is configured to apply a second pulse-width modulated alternating signal to the second inductor during the first step to increase the temperature of the second portion of the susceptor system from an initial temperature to a third operating temperature, lower than the first operating temperature, wherein the controller is configured to supply a second pulse width modulated alternating signal during the first stage with a duty cycle of less than 50%, preferably less than 40%, preferably less than 30%, more preferably less than 20%, and most preferably less than 10% . 5. The aerosol generating device of claim 4, wherein the controller is configured to apply a second pulse width modulated alternating signal to the second inductor during a second step to increase the temperature of the second portion of the current collector system from a third operating temperature to a fourth operating temperature above a second operating temperature, wherein the controller is configured to supply a second pulse width modulated alternating signal with a duty cycle greater than 50%, preferably greater than 60%, preferably greater than 70%, more preferably greater than 80%, and most preferably greater than 90%. 6. The aerosol generating device as claimed in any one of the preceding claims, further comprising a power source for supplying power to the induction heating system. 7. An aerosol generating device according to any of the previous paragraphs, wherein the controller comprises a microcontroller. 8. The aerosol generating device of claim 7, wherein the microcontroller is configured to use a clock frequency of the microcontroller as one or both of the frequency of variation of the first pulse-width modulated variable signal and the frequency of variation of the second pulse-width modulated variable signal. 9. An aerosol generating device according to any one of paragraphs. 1-7, further comprising a generator for generating one or both of the frequency of the first pulse-width modulated alternating signal and the frequency of the second pulse-width modulated alternating signal. 10. The aerosol generating device of any one of the preceding claims, further comprising a first power stage comprising at least a first inductor and a first capacitor. 11. The aerosol generating device according to claim 10, wherein the first inductor and the first capacitor are arranged as a first LC circuit. 12. The aerosol generating device of any one of the preceding claims, further comprising a second power stage comprising at least a second inductor and a second capacitor. 13. The aerosol generating device according to claim 12, wherein the second inductor and the second capacitor are arranged as a second LC circuit. 14. The aerosol generating device according to any one of the preceding claims, wherein the second coil is wound in a direction different from the winding direction of the first coil. 15. The aerosol generating device according to any of the preceding claims, wherein the second coil has a different number of turns than the first coil. 16. The aerosol generating device according to any of the preceding claims, wherein the second coil has a length different from the length of the first coil. 17. The aerosol-generating device of any one of the preceding claims, comprising a device cavity configured to receive an aerosol-forming substrate, a first inductor located around the device cavity and a second inductor also located around the device cavity. 18. The aerosol generating device of claim 17, wherein the cavity of the device has a proximal end and a distal end opposite the proximal end, the proximal end being open to receive the aerosol generating article. 19. The aerosol generating device of claim 18, wherein the first inductor is located closer to the proximal end of the device cavity than to the distal end of the device cavity, and the second inductor is located closer to the distal end of the device cavity than to the proximal end of the device cavity. 20. An aerosol generating system comprising an aerosol generating device according to any one of claims. 1-19 and an aerosol-generating article containing an aerosol-forming substrate. 21. A method for controlling an aerosol-generating device containing: an induction heating system configured to heat an aerosol-forming substrate and comprising: a current collecting system configured to be heated by a penetrating varying magnetic field to heat the aerosol-forming substrate; at least a first inductor; at least a second inductor; And a controller configured to control the first inductor and the second inductor, wherein the method includes: energizing the first inductor with a first pulse-width modulated alternating signal to generate a first alternating magnetic field for heating the first portion of the current collector system, energizing the second inductor with a second pulse-width modulated alternating signal to generate a second alternating magnetic field for heating the second portion of the current collector system, and supplying a first pulse-width modulated alternating signal with a duty cycle complementary to the duty cycle of the second pulse-width modulated alternating signal. 22. The method of claim 21, wherein a first pulse-width modulated alternating signal is applied to the first inductor during a first step to increase the temperature of the first portion of the current collector system from an initial temperature to a first operating temperature, wherein the alternating pulse-width modulated signal supplied during the first stage with a duty cycle above 50%, preferably above 60%, preferably above 70%, more preferably above 80% and most preferably above 90%. 23. The method of claim 22, wherein a first pulse width modulated alternating signal is applied to the first inductor during a second step to reduce the temperature of the first portion of the current collector system from a first operating temperature to a second operating temperature, wherein the first alternating pulse width modulated signal pulse modulation is applied during the second stage with a duty cycle below 50%, preferably below 40%, preferably below 30%, more preferably below 20% and most preferably below 10%. 24. The method of claim 22 or 23, wherein a second pulse width modulated alternating signal is applied to the second inductor during the first step to increase the temperature of the second portion of the current collector system from an initial temperature to a third operating temperature, wherein the second pulse width modulated alternating signal -pulse modulation is applied during the first stage with a duty cycle below 50%, preferably below 40%, preferably below 30%, more preferably below 20% and most preferably below 10%. 25. The method of claim 24, wherein a second pulse-width modulated alternating signal is applied to the second inductor during a second step to increase the temperature of the second portion of the current collector system from a third operating temperature to a fourth operating temperature, wherein the second alternating pulse-width modulated signal pulse modulation is applied during the second stage with a duty cycle greater than 50%, preferably greater than 60%, preferably greater than 70%, more preferably greater than 80%, and most preferably greater than 90%. 26. Method according to any one of paragraphs. 21-25, according to which the aerosol generating device is an aerosol generating device according to any one of paragraphs. 1-19.

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