RU2818904C2 - Induction heating system with segmented induction heating element - Google Patents

Abstract

FIELD: smoking accessories.

SUBSTANCE: invention relates to an induction heating element for an aerosol generating system, to an induction heating system, to an aerosol generating device with an induction heating system and an aerosol generating system, with an aerosol generating device comprising an induction heating system. Invention improves the ability of the induction heating element to selectively heat separate parts of the aerosol-forming substrate. For this purpose, an induction heating element (10) for an aerosol generating system, an induction heating system for an aerosol generating system, an aerosol generating device with an induction heating system are proposed and an aerosol generating system with an aerosol generating device comprising an induction heating system. Induction heating element (10) comprises: first current collector (12), wherein first current collector (12) is a tubular current collector defining an inner cavity for receiving an aerosol-forming substrate; second current collector (14), wherein second current collector (14) is a tubular current collector defining an inner cavity for receiving an aerosol-forming substrate; and gap (15) between first current collector (12) and second current collector (14), wherein gap (15) thermally insulates first current collector (12) from second current collector (14).

EFFECT: disclosed is an induction heating system with a segmented induction heating element.

16 cl, 8 dwg

Description

The present invention relates to an induction heating element for an aerosol generating system, an induction heating system for an aerosol generating system, an aerosol generating device with an induction heating system, and an aerosol generating system with an aerosol generating device comprising an induction heating system.

The prior art has proposed a number of electrical aerosol generating systems in which an aerosol generating device having an electrical heater is used to heat an aerosol generating substrate such as a tobacco plug. One of the goals of such aerosol-generating systems is to reduce the amount of known harmful smoke components produced by combustion and pyrolytic degradation of tobacco in conventional cigarettes. Typically, the aerosol generating substrate is provided as part of an aerosol generating article that is inserted into a cavity in the aerosol generating device. In some known systems for heating the aerosol-forming substrate to a temperature at which it is capable of releasing volatile components capable of forming an aerosol, a resistive heating element, such as a heating plate, is inserted into or located around the aerosol-forming substrate when the article is contained. into an aerosol generating device. Other aerosol generating systems use an induction heater instead of a resistive heating element. The induction heater typically includes an induction coil forming part of the aerosol generating device and a susceptor located in thermal proximity to the aerosol generating substrate. The inductor generates a varying magnetic field to generate eddy currents and hysteresis losses in the pantograph, causing the pantograph to heat up, thereby heating the aerosol-forming substrate. Inductive heating provides the ability to generate an aerosol without the heater affecting the aerosol-generating product. This may increase the ease with which the heater can be cleaned.

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

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

The present invention provides an induction heating element for an aerosol generating system. The induction heating element may include a first current collector. The first susceptor may be a tubular susceptor defining an internal cavity for receiving the aerosol-forming substrate. The induction heating element may include a second current collector. The second pantograph may be a tubular pantograph defining an internal cavity for receiving the aerosol-forming substrate. The induction heating element may further include a space between the first pantograph and the second pantograph. The gap may thermally isolate the first pantograph from the second pantograph.

The present invention provides an induction heating element for an aerosol generating system, the induction heating element comprising: a first pantograph, the first pantograph being a tubular pantograph defining an internal cavity for receiving an aerosol generating substrate; a second pantograph, the second pantograph being a tubular pantograph defining an internal cavity for receiving the aerosol-forming substrate; and a gap between the first pantograph and the second pantograph, the gap thermally insulating the first pantograph from the second pantograph.

Providing the induction heating element with a gap between the first pantograph and the second pantograph may reduce conductive heat transfer between the first pantograph and the second pantograph compared to an induction heating element comprising a single pantograph of the same length. This may improve the ability of the induction heating element to selectively heat separate portions of the aerosol-forming substrate.

The present invention provides an induction heating system for an aerosol generating system.

The induction heating system may include an induction heating element. The induction heating element may include a first current collector. The first susceptor may be a tubular susceptor defining an internal cavity for receiving the aerosol-forming substrate. The induction heating element may include a second current collector. The second pantograph may be a tubular pantograph defining an internal cavity for receiving the aerosol-forming substrate. The induction heating element may further include a space between the first pantograph and the second pantograph. The gap may thermally isolate the first pantograph from the second pantograph.

The induction heating system may further include a first induction coil. The induction heating system may further include a second induction coil. The first induction coil may be positioned relative to the induction heating element such that a varying electric current supplied to the first induction coil generates a varying magnetic field that heats the first current collector of the induction heating element. The second induction coil may be positioned relative to the induction heating element such that a varying electrical current supplied to the second induction coil generates a varying magnetic field that heats the second current collector of the induction heating element.

Specifically, the present invention provides an induction heating system for an aerosol generating system, the induction heating system including: an induction heating element, a first induction coil, and a second induction coil. The induction heating element includes: a first susceptor, the first susceptor being a tubular susceptor defining an internal cavity for receiving an aerosol-forming substrate; a second pantograph, the second pantograph being a tubular pantograph defining an internal cavity for receiving the aerosol-forming substrate; and a gap between the first pantograph and the second pantograph, the gap thermally insulating the first pantograph from the second pantograph. The first induction coil is positioned relative to the induction heating element such that a varying electric current supplied to the first induction coil generates a varying magnetic field that heats the first current collector of the induction heating element. The second induction coil is positioned relative to the induction heating element such that a varying electric current supplied to the second induction coil generates a varying magnetic field that heats the second current collector of the induction heating element.

Providing the induction heating system with a first induction coil positioned to heat the pantograph of the induction heating element and a second induction coil positioned to heat the second pantograph of the induction heating element provides selective heating of the first pantograph and the second pantograph. This selective heating allows the induction heating system to heat different parts of the aerosol-forming substrate at different times, and can cause one of the susceptors to be heated to a different temperature than the other susceptor.

The present invention provides an aerosol generating device comprising an induction heating system.

The induction heating system may include an induction heating element. The induction heating element may include a first current collector. The first susceptor may be a tubular susceptor defining an internal cavity for receiving the aerosol-forming substrate. The induction heating element may include a second current collector. The second pantograph may be a tubular pantograph defining an internal cavity for receiving the aerosol-forming substrate. The induction heating element may further include a space between the first pantograph and the second pantograph. The gap may thermally isolate the first pantograph from the second pantograph.

The induction heating system may further include a first induction coil. The induction heating system may further include a second induction coil. The first induction coil may be positioned relative to the induction heating element such that a varying electric current supplied to the first induction coil generates a varying magnetic field that heats the first current collector of the induction heating element. The second induction coil may be positioned relative to the induction heating element such that a varying electric current supplied to the second induction coil generates a varying magnetic field that heats the second current collector of the induction heating element.

In particular, the present invention provides an aerosol generating device comprising a device body defining a device cavity for receiving an aerosol generating substrate. The aerosol generating device further comprises an induction heating system including an induction heating element, a first induction coil and a second first induction coil. The induction heating element includes: a first current collector located around a first portion of the device cavity; a second current collector located around the second portion of the device cavity; and a gap between the first pantograph and the second pantograph, the gap thermally insulating the first pantograph from the second pantograph. The aerosol generating device further comprises: a first induction coil located around at least a portion of the first pantograph and a first cavity portion of the device; a second induction coil disposed around at least a portion of the second pantograph and a second portion of the device cavity; and a power supply connected to the induction heating system and configured to supply a varying electric current to the first induction coil and the second induction coil. When a varying electric current is applied to the first induction coil, the first induction coil generates a varying magnetic field that heats the first current collector. When a varying electric current is applied to the second induction coil, the second induction coil generates a varying magnetic field that heats the second current collector.

Providing the aerosol generating device with an induction heating system comprising a first susceptor located around a first portion of the device cavity and a second susceptor located around a second portion of the device cavity may provide selective heating of a first portion of the device cavity by the first susceptor and a second portion of the device cavity by the second susceptor. Providing a first induction coil positioned to heat the first pantograph and a second induction coil positioned to heat the second pantograph may provide selective heating of the first pantograph and the second pantograph. This selective heating allows the induction heating system to heat different parts of the aerosol-forming substrate located in the device cavity at different times and at different temperatures. Advantageously, this may allow the aerosol generating device to generate aerosols having different characteristics, increasing the functionality and flexibility of the aerosol generating device.

The present invention provides an aerosol generating system. The aerosol generating system comprises an aerosol generating article containing an aerosol generating substrate, and the aerosol generating device is configured to accommodate at least a portion of the aerosol generating article. The aerosol generating article may comprise a first aerosol generating substrate; and a second aerosol-forming substrate. The aerosol generating device may include an induction heating system. The induction heating system may include an induction heating element. The induction heating element may include a first current collector. The first susceptor may be a tubular susceptor defining an internal cavity for receiving the aerosol-forming substrate. The induction heating element may include a second current collector. The second pantograph may be a tubular pantograph defining an internal cavity for receiving the aerosol-forming substrate. The induction heating element may further include a space between the first pantograph and the second pantograph. The gap may thermally isolate the first pantograph from the second pantograph. The induction heating system may further include a first induction coil. The induction heating system may further include a second induction coil. The first induction coil may be positioned relative to the induction heating element such that a varying electric current supplied to the first induction coil generates a varying magnetic field that heats the first current collector of the induction heating element. The second induction coil may be positioned relative to the induction heating element such that a varying electrical current supplied to the second induction coil generates a varying magnetic field that heats the second current collector of the induction heating element. The induction heating system may be arranged such that the first susceptor is positioned to heat the first aerosol-generating substrate of the aerosol-generating article when the aerosol-generating article is located in the aerosol-generating device. The induction heating system may be arranged such that the second susceptor is positioned to heat the second aerosol-generating substrate of the aerosol-generating article when the aerosol-generating article is located in the aerosol-generating device.

Advantageously, such an aerosol generating system may be configured to selectively heat the first aerosol generating substrate and the second aerosol generating substrate of the aerosol generating article. The second aerosol-forming substrate may be heated at a different time than the first aerosol-forming substrate. The second aerosol-forming substrate may be heated to a different temperature than the first aerosol-forming substrate. This may allow the aerosol generating system to generate an aerosol having particularly desirable characteristics, and may allow the aerosol generating system to generate aerosols having different characteristics.

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

As used herein, the term “aerosol-generating article” refers to an article containing an aerosol-forming substrate that is capable of releasing volatile compounds that can form an aerosol. For example, an aerosol generating product may be one that generates an aerosol that is directly inhaled by a user inhaling or puffing from a mouthpiece at the proximal or user end of the system. The aerosol-generating product may be disposable. An article containing a substrate forming an aerosol 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 "varying current" includes any type of current that changes over time to generate a varying magnetic field. The term "variable current" is intended to include varieties of alternating current. In case the changing current is alternating current, the alternating current generates an alternating magnetic field.

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

As used herein, the term "width" means the basic dimension in the transverse direction of an aerosol generating device or aerosol generating article, or a component of an aerosol generating device or an aerosol generating article, at a specific location along its length. The term "thickness" means 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 aerosol generating article, or a component of an aerosol generating device or 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 mouthpiece 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 present invention provides an induction heating element for an aerosol generating system.

The induction heating element may be an external heating element. As used herein, the term “external heating element” refers to a heating element configured to heat the outer surface of the aerosol-forming substrate.

The external heating element is preferably configured to at least partially enclose the aerosol-forming substrate when the aerosol-forming substrate is accommodated in the aerosol-generating device. The induction heating element may be configured to heat an outer surface of the aerosol-forming substrate when the aerosol-forming substrate is received within the cavity of the induction heating element.

The induction heating element contains a cavity to receive an aerosol-forming substrate. The induction heating element may include an outer side and an inner side opposite the outer side. The inner side may at least partially define a cavity of the induction heating element for receiving the aerosol-forming substrate. The first pantograph is a tubular pantograph forming part of the cavity of the induction heating element. The second pantograph is a tubular pantograph forming part of the cavity of the induction heating element.

In some embodiments, the induction heating element includes multiple internal cavities to accommodate an aerosol-forming substrate. The internal cavity of the first pantograph may define a first cavity of the induction heating element, and the internal cavity of the second pantograph may define a second cavity of the induction heating element.

In some preferred embodiments, the induction heating element includes a single internal cavity for receiving the aerosol-forming substrate. In these embodiments, the internal cavity of the first pantograph defines a portion of the single internal cavity of the induction heating element, and the internal cavity of the second pantograph defines a second portion of the single internal cavity of the induction heating element. In some preferred embodiments, the induction heating element is a tubular induction heating element. The inner surface of the tubular induction heating element may define a cavity of the induction heating element.

In those embodiments where the aerosol generating device includes a device cavity for receiving an aerosol generating substrate, an induction heating element may at least partially surround the device cavity. The cavity of the induction heating element may be aligned with the cavity of the device.

The induction heating element contains a first current collector and a second current collector.

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 may be formed from any material that can be inductively heated to a temperature sufficient to aerosolize the aerosol-forming substrate. Preferred pantographs may be heated to temperatures in excess of approximately 250 degrees Celsius. Preferred current collectors may be formed from an electrically conductive material. As used herein, the term "electrically conductive" refers to materials having an electrical resistivity of less than or equal to 1 x10 ^-4 ohm-meter (Ohm-m), at twenty degrees Celsius. Preferred current collectors may be formed from 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/(mK)) at 23 degrees Celsius and 50 percent relative humidity, when measured using the method modified transient planar 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 current collector may contain at least about 5 percent, at least about 20 percent, at least about 50 percent, or at least about 90 ferromagnetic or paramagnetic materials.

Preferably, the current collector is formed from a material that is substantially impermeable to gas. In other words, preferably the current collector is formed from a material that is not permeable to gas.

The first pantograph is a tubular pantograph. The second pantograph is a tubular pantograph. The tubular current collector contains an annular body forming an internal cavity. The cavity of the current collector is configured to accommodate a substrate that forms an aerosol. 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 case the pantograph is a tubular pantograph having a cavity for receiving the aerosol-forming substrate that is open at one end or both ends, preferably the pantograph is substantially gas-tight from the outer surface to the inner surface defining the inner cavity. In other words, preferably the pantograph is substantially gas-tight through the side walls of the pantograph.

The current collector of the induction heating element can take any suitable shape. For example, the pantograph may be oblong. The pantograph may have any suitable cross-section. For example, the pantograph may have a circular, elliptical, square, rectangular, triangular, or other polygonal cross-section.

In some embodiments, each pantograph is substantially identical. For example, the second pantograph may be substantially identical to the first pantograph. All pantographs can be formed from the same material. All pantographs can have the same shape and size. Making each pantograph identical to the other pantographs can ensure that each pantograph is heated to substantially the same temperature and heated 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 formed from 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. Making each pantograph different from other pantographs can ensure that each pantograph is adapted to optimally heat 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 formed from a first material suitable for heating the first aerosol-forming substrate to a first temperature, and the second susceptor may be formed from a second material different from the first material suitable for heating the second aerosol-forming substrate to second temperature.

In another example, an aerosol-generating article may comprise a first aerosol-generating substrate having a first length, and a second aerosol-generating substrate having a second length different from the first length, such that heating the second aerosol-generating substrate generates a different amount of aerosol, than heating the first 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 an oblong 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 coaxially aligned.

The induction heating element may contain any suitable number of current collectors. The induction heating element contains several current collectors. The induction heating element contains at least two current collectors. For example, an induction heating element may contain three, four, five or six current collectors. If the induction heating element contains more than two pantographs, an intermediate element may be located between each adjacent pair of pantographs.

In some preferred embodiments, the pantograph may comprise a pantograph layer provided on the support body. Each of the first pantograph and the second pantograph may be formed from a support body and a pantograph layer. The placement of a pantograph in a changing magnetic field induces eddy currents in close proximity to the surface of the pantograph, that is, it creates an effect called the skin effect. Accordingly, it is possible to form a susceptor from a relatively thin layer of susceptor material, which at the same time ensures efficient heating of the susceptor in the presence of a changing magnetic field. Constructing the susceptor from a support body and a relatively thin susceptor layer can facilitate the production of an aerosol generating article that is simple, inexpensive and reliable.

The supporting main part can be made of a material that is not subject to induction heating. Advantageously, this can reduce heating of the pantograph surfaces that are not in contact with the aerosol-generating substrate, where the surfaces of the support body form pantograph surfaces that are not in contact with the aerosol-generating substrate.

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

The support body may include thermal insulation material for thermally insulating the first pantograph from the second pantograph. As used herein, the term "thermal insulating material" is used to describe a material having a volumetric thermal conductivity of less than or equal to approximately 40 watts per meter-Kelvin (W/(mK)) at a temperature of 23 degrees Celsius and 50 percent relative humidity, when measured with using the modified transient planar source (MTPS) method.

Forming a support body of thermal insulation material can provide a thermal barrier between the current collector layer and other components of the induction heating system, such as an induction coil surrounding the induction heating element. Advantageously, this can 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 collector layer may be provided on an inner surface of the tubular support body. By providing a susceptor layer on the inner surface of the support body, it is possible to position the susceptor layer adjacent to the aerosol-forming substrate in the cavity of the induction heating element, improving heat transfer between the susceptor layer and the aerosol-forming substrate.

In some preferred embodiments, the first pantograph comprises a tubular support body formed from a thermal insulation material and a pantograph layer on an inner surface of the tubular support body. In some preferred embodiments, the second pantograph comprises a tubular support body formed from a thermal insulation material and a pantograph layer on an inner surface of the tubular support body.

The current collector may be provided with a protective outer layer, for example a protective ceramic layer or a protective glass layer. The protective outer layer can improve the strength of the pantograph and make the pantograph easier to clean. The protective outer layer may substantially enclose the current collector. The current collector may contain a protective coating formed from glass, ceramics or inert metal.

The induction heating element includes a space between the first pantograph and the second pantograph.

The gap may be of any suitable size to thermally insulate the first pantograph from the second pantograph.

The induction heating element may include an intermediate element located between the first pantograph and the second pantograph. The intermediate element may be located in the space between the first pantograph and the second pantograph. The intermediate element may extend between the first pantograph and the second pantograph. The intermediate element may contact the end of the first pantograph. The intermediate element may contact the end of the second pantograph. The intermediate element may be attached to the end of the first pantograph. The intermediate element may be attached to the end of the second pantograph. The intermediate element may connect the second pantograph to the first pantograph. If the intermediate element connects the second pantograph to the first pantograph, the intermediate member may provide structural support to the induction heating element. Advantageously, the intermediate element can provide the induction heating element as a single integral element that can be easily removed from the induction heating system and replaced.

The intermediate element may take 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 defining an internal cavity. The intermediate element may be configured to allow gas to penetrate from the outside of the intermediate element into the internal cavity. The cavity of the intermediate element may be configured to accommodate 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 and the second pantograph are tubular pantographs, and the intermediate element is a tubular intermediate element. In these embodiments, the tubular first pantograph, tubular second pantograph, and tubular intermediate member may be substantially aligned. The tubular first pantograph, the tubular intermediate member, and the tubular second pantograph may be arranged end to end in the shape 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 member, and the tubular second pantograph may define a cavity of the induction heating element.

The intermediate element may be formed from any suitable material.

In preferred embodiments, the intermediate element is formed from a different material relative to the first pantograph and the second pantograph.

The intermediate element may contain thermal insulating material for thermally insulating the first pantograph from the second pantograph. 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/(mK)) at a temperature of 23 degrees Celsius and 50 percent relative humidity, as measured using a modified transient planar source (MTPS) method ). Providing an intermediate member formed of a thermal insulating material in the space between the first pantograph and the second pantograph can further reduce heat transfer between the first pantograph and the second pantograph. Advantageously, this can improve the ability of the induction heating element to selectively heat separate portions of the aerosol-forming substrate. This may also make it possible to reduce the size of the gap between the first pantograph and the second pantograph and, in turn, reduce the size of the induction heating element.

The intermediate element may include electrically insulating material for electrically insulating the first pantograph from the second pantograph. 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 the following: thermal insulation material for thermally insulating the first pantograph from the second pantograph; and an electrical insulating material for electrically insulating the first pantograph from the second pantograph. In some preferred embodiments, the intermediate element comprises thermal insulating material for thermally insulating the first pantograph from the second pantograph; and an electrical insulating material for electrically insulating the first pantograph from the second pantograph.

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 member is formed from a gas-impermeable material and includes an air passage configured to allow air to pass through the intermediate member. The intermediate element may contain several air passages. The intermediate element may comprise any suitable number of air passages, for example two, three, four, five or six air passages. In case the intermediate element contains multiple air passages, the air passages may be evenly spaced from 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 the internal cavity. The intermediate element may include an air passage extending from the outer surface to the inner surface. In case the tubular intermediate member contains multiple air passages, the air passages may be evenly spaced around the circumference of the tubular intermediate member.

An induction heating element may be contained in an induction heating system.

The induction heating system further includes an induction coil. Preferably, the induction heating system includes a first induction coil and a second induction coil.

The first induction coil is configured such that a varying electric current supplied to the first induction coil generates a varying magnetic field. The first induction coil is positioned relative to the induction heating element such that a varying electric current supplied to the first induction coil generates a varying magnetic field that heats the first current collector of the induction heating element.

The second induction coil is configured such that a varying electric current supplied to the second induction coil generates a varying magnetic field. The second induction coil is positioned relative to the induction heating element such that a varying electric current supplied to the second induction coil generates a varying magnetic field that heats the second current collector of the induction heating element.

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

The induction coil may be formed from any suitable material. The induction coil is formed from an electrically conductive material. Preferably, the induction coil is formed from a metal or a metal alloy.

In case the induction coil is a tubular induction coil, preferably the induction heating element portion is located inside the inner cavity of the induction coil. Particularly preferably, the first induction coil is a tubular induction coil, and at least part of the first current collector is located inside the inner cavity of the first induction coil. The length of the tubular first induction coil may be substantially similar to the length of the first pantograph. Particularly preferably, the second induction coil is a tubular induction coil, and at least part of the second current collector is located inside the inner cavity of the second induction coil. The length of the tubular second induction coil may be substantially similar to the length of the second current collector.

In some embodiments, the second telecoil is substantially identical to the first telecoil. In other words, the first induction coil and the second induction coil have the same shape, size and number of turns. Particularly preferably, the second induction coil is substantially identical to the first induction coil in those embodiments where the second pantograph is substantially identical to the first pantograph.

In some embodiments, the second induction coil is different from the first induction coil. For example, the second induction coil may have a different length, number of turns, or cross-section than the first induction coil. Particularly preferably, the second induction coil is different from the first induction coil in those embodiments where the second pantograph is different from the first pantograph.

The first induction coil and the second induction coil may be located in any suitable system. Particularly preferably, the first induction coil and the second induction coil are coaxially aligned along an axis. In case the first induction coil and the second induction coil are elongated tubular induction coils, the first induction coil and the second induction coil can be coaxially aligned along the longitudinal axis so that the internal cavities of the coils are aligned along the longitudinal axis.

The induction heating system may contain any suitable number of induction coils. An induction heating element contains several induction coils. The induction heating system includes at least two induction coils. Preferably, the number of induction coils of the induction heating system is equal to the number of current collectors of the induction heating element. The number of induction coils of an induction heating system may differ from the number of current collectors of an induction heating element. In case the number of induction coils is equal to the number of pantographs, preferably each induction coil is located around a pantograph. Particularly preferably, each induction coil extends substantially along the length of the pantograph around which it is located.

The induction heating element may include a flux concentrator. The flux concentrator may be located around the induction coil of the induction heating system. The flux concentrator is configured to deform the changing magnetic field generated by the induction coil in the direction of the induction heating element.

Advantageously, by deforming the electromagnetic field in the direction of the induction heating element, the flux concentrator can concentrate the magnetic field on the induction heating element. This may increase the efficiency of the induction heating system compared to embodiments in which a flux concentrator is not provided. As used herein, the phrase “concentrate a magnetic field” means to deform a magnetic field such 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 having a high relative magnetic permeability that serves to concentrate and direct the magnetic field or magnetic field lines generated by the induction coil. 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 4 π × 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 25 degrees Celsius, for example at least 10, at least 20, at least 30, at least 40, at at least 50, at least 60, at least 80 or at least 100 degrees Celsius. These exemplary values preferably refer to relative permeability values for 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 comprises a ferromagnetic material, for example 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 located around the first induction coil and the second induction coil. In these embodiments, the flux concentrator is configured to deform the varying magnetic field generated by the first induction coil toward the first induction heating element susceptor and to deform the varying magnetic field generated by the second induction coil toward the second induction heating element susceptor.

In some of these embodiments, a portion of the flux concentrator extends into an intermediate element between the first pantograph and the second pantograph. Passing a portion of the flux concentrator into the intermediate element between the first pantograph and the second pantograph may further deform the magnetic field generated by the first induction coil and the magnetic field generated by the second induction coil. This additional deformation may result in an additional concentration of the magnetic field generated by the first induction coil in the direction of the first pantograph and an additional concentration of the magnetic field generated by the second induction coil in the direction of the second pantograph. This can further improve the efficiency of the induction heating system.

In some embodiments, the induction heating system includes multiple flux concentrators. In some preferred embodiments, a separate flux concentrator is located around each induction coil. Providing each induction coil with a dedicated flux concentrator may allow the flux concentrator to be optimally configured to deform the magnetic field generated by the induction coil. Such a system can also provide the formation of an induction heating system from modular induction heating units. Each induction heating assembly may include an induction coil and a flux concentrator. Providing modular induction heating assemblies can speed up the standardized production of an induction heating system and provide the ability to remove and replace individual assemblies.

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

In these preferred embodiments, a portion of the first flux concentrator may extend into an intermediate element between the first pantograph and the second pantograph. In these preferred embodiments, a portion of the second flux concentrator may extend into an intermediate element between the first pantograph and the second pantograph. The passage of a portion of the flux concentrator into the intermediate element between the pantographs may allow the flux concentrator to further deform the magnetic field generated by the induction coil in the direction of the pantograph.

The induction heating system may further comprise an induction heating system housing. The housing can connect together the induction heating element, induction coils and flux concentrators. This can help solidify the relative layouts of the induction heating system components and improve the interface between components. Preferably, the body of the induction heating system is formed from an electrically insulating material.

In the event that the induction heating system includes separate induction heating units comprising an induction coil and a flux concentrator, each induction heating unit may include an induction heating unit body. The induction heating unit body can assemble the components of the induction heating unit and improve the interface between components. Preferably, the body of the induction heating unit is formed from an electrically insulating material.

The induction heating system may be contained in an aerosol generating device.

The aerosol generating device may include a power supply. The power supply may be any suitable type of power supply. The power supply may be a DC power supply. In some preferred embodiments, the power supply is a battery, such as a rechargeable lithium-ion battery. The power supply may be another type of charge storage device, such as a capacitor. The power supply may need to be recharged. The power supply may have a capacity that allows sufficient energy to be stored for one or more uses of the device. For example, the power supply may have sufficient capacity to continuously generate 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 another example, the power supply may have sufficient capacity to support a predetermined number of device uses 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 amp to about 10 amps (corresponding to DC power supply power ranges from approximately 2.5 watts to approximately 45 watts).

The aerosol generating device may comprise a controller coupled to an induction heating system and a power supply. In particular, the aerosol generating device may include a controller coupled to the first induction coil and the second induction coil and the power supply. The controller is configured to control the power supply to the induction heating system from the power supply. 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. The current may be supplied to the induction heating system continuously upon activation of the aerosol generating device, or may be supplied intermittently, such as from puff to puff.

The controller may advantageously comprise a DC-AC converter, which may comprise a Class C, Class D or Class E power amplifier.

The controller may be configured to supply varying current to the induction heating system at any suitable frequency. The controller may be configured to supply varying current to the induction heating system at a frequency of from about 5 kilohertz to about 30 megahertz. In some preferred embodiments, the controller is configured to supply varying current to the induction heating system from about 5 kilohertz to about 500 kilohertz. In some embodiments, the controller is configured to supply high frequency varying current to the induction heating system. As used herein, the term “high frequency alternating current” refers to alternating current with a frequency of about 500 kilohertz to about 30 megahertz. The high frequency varying current 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 comprise a device housing. The body of the device may be oblong. The device body 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 body may define a device cavity for receiving the aerosol-forming substrate. The cavity of the device may be configured to accommodate 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.

An induction heating element may be located in the cavity of the device. An induction heating element may be located around the cavity of the device. If the induction heating element is a tubular induction heating element, the induction heating element may surround a cavity of the device. The inner surface of the induction heating element may form the inner surface of a cavity of the device.

The first induction coil and the second induction coil may be located in the cavity of the device. The first induction coil and the second induction coil may be located around the cavity of the device. The first induction coil and the second induction coil may surround the device cavity. The inner surface of the first induction coil and the second induction coil 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 body of the device may include an air inlet. The air inlet hole may be configured to allow ambient air to enter the device body. The body of the device may include any suitable number of air inlet openings. The body of the device may contain multiple air inlets.

The body of the device may include an air outlet. The air outlet may be configured to allow air to enter the device cavity from the device body. The body of the device may include any suitable number of air outlets. The device body may contain multiple air outlets.

In case the intermediate element of the induction heating element is gas-permeable, the aerosol generating device may determine an air flow path extending from the air inlet to the intermediate element of the induction heating element. Such an air flow path may allow air to be drawn through the aerosol generating device, through the air inlet, and into the device cavity through the intermediate member.

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 towards a proximal end of the device cavity. The ring seal may extend into the cavity of the device. The O-ring may provide a substantially airtight seal between the body of the device and the outer surface of the aerosol generating article contained within the cavity of the device. This may reduce the amount of air drawn into the device cavity during use through any gaps between the outer surface of the aerosol generating article and the inner surface of the device cavity. This may increase the volume of air drawn into the aerosol generating article through the permeable intermediate members.

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 contain more than one air inlet. The one or more air inlets may reduce the temperature of the aerosol before delivery to the user and may reduce the concentration of the aerosol before delivery to the user.

In some embodiments, the mouthpiece is provided as part of the 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.

The aerosol generating device may include a temperature sensor. The temperature sensor may be configured to sense the temperature of the induction heating element. The aerosol generating device may include a first temperature sensor configured to measure the temperature of the first pantograph. The aerosol generating device may include a second temperature sensor configured to measure the temperature of the second pantograph.

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 indicating the status of the aerosol generating device or substrate.

The aerosol generating device may include a puff sensor to detect when a user takes a puff through the aerosol generating system.

Preferably, the aerosol generating device is portable. The aerosol-generating device may be comparable in size to 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 comprise a first aerosol generating substrate; and a second aerosol-forming substrate. When an aerosol-generating article is received in a device cavity, at least a portion of the first aerosol-generating substrate may be received in a first portion of the device cavity, and at least a portion of a second aerosol-generating substrate may be received in a second portion of the device cavity.

An induction heating element forming part of the induction heating system of the aerosol generating device is configured to heat the aerosol generating substrate.

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

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 a 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 contain homogenized material of plant origin. The aerosol-forming substrate may comprise homogenized tobacco material. Homogenized tobacco material can be formed 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 generating 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 essentially resistant to thermal degradation 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. When present, the homogenized tobacco material may have an aerosol forming agent content equal to 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-generating substrate may be contained in the aerosol-generating article. An 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 essentially oblong. 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 multiple aerosol generating substrates. The aerosol generating segment may comprise a first aerosol generating substrate and a second aerosol generating 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 multiple aerosol generating substrates, the number of aerosol generating substrates may be the same as the number of current collectors in the induction heating element. Likewise, the number of aerosol-forming substrates may be the same as the number of induction coils in the induction heating system.

The aerosol generating segment may have a substantially cylindrical shape. The aerosol generating segment may be essentially oblong. 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 multiple 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 45 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 can be 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 product may include a filter plug. The filter plug may be located at the proximal end of the aerosol generating product. 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 aerosol generating article may comprise an outer wrapper. The outer wrapper may be formed from paper. The outer wrap may be permeable to gas in the aerosol generating segment. Particularly, in embodiments providing multiple aerosol-forming substrates, the outer wrap may include perforations or other air inlets at the interface between adjacent aerosol-forming substrates. Where a gap is provided between adjacent aerosol-forming substrates, the outer wrap may include perforations or other air inlets in the gap. This can provide a direct supply of air to the aerosol-forming substrate without being drawn in through another aerosol-forming substrate. This can increase the amount of air taken up by each aerosol-forming substrate. This can 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. The gap may be approximately 18 millimeters in size, but may range in size from about 5 millimeters to about 25 millimeters.

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

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 an induction heating element according to one embodiment of the present invention located between a pair of induction coils;

in fig. 2 is a schematic illustration of an induction heating element according to one embodiment of the present invention located between a pair of induction coils;

in fig. 3 is an exploded perspective view of an induction heating element according to one embodiment of the present invention;

in fig. 4 is a perspective view of the induction heating element of FIG. 3;

in fig. 5 is a cross-sectional view of an aerosol generating system according to one 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 cross-sectional view of a proximal end of the aerosol generating device shown in FIG. 5;

in fig. 7 is a cross-sectional view of the aerosol generating system shown in FIG. 5, wherein the aerosol generating article is located in the aerosol generating device; And

Figure 8 is a cross-sectional view of a modular induction heating system according to an embodiment of the present invention, the induction heating system comprising two stacked induction heating units, each induction heating unit including a current collector having thermally insulating and electrically insulating intermediate members disposed on both ends, induction coil, flux concentrator and housing.

In fig. 1 is a schematic diagram of an induction heating element 10 according to one embodiment of the present invention. The induction heating element 10 is an elongated tubular element with a circular cross section. The induction heating element 10 includes a first pantograph 12, a second pantograph 14, and a space 15 between the first pantograph 12 and the second pantograph 14. Both the first pantograph 12 and the second pantograph 14 are elongated tubular members with 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 induction heating element 10 includes a cylindrical cavity 20, open at both ends, defined by the internal 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 aerosol-generating article may be heated by the first susceptor and the second susceptor, thereby heating the aerosol-generating substrate.

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

The first induction coil 32 is located around the first pantograph 12 and extends substantially the length of the first pantograph 12. As such, the first pantograph 12 is surrounded by the first induction coil 32 substantially along its length. When a varying electric current is applied to the first induction coil 32, the first induction coil 32 generates a varying magnetic field concentrated in the first portion 22 of the cavity 20. Such varying magnetic field generated by the first induction coil 32 induces eddy currents in the first pantograph 12, causing the first pantograph to heat up. pantograph 12.

The second induction coil 34 is located around the second pantograph 14 and extends substantially the length of the second pantograph 14. As such, the second pantograph 14 is surrounded by the second induction coil 34 substantially along its length. When a varying electric current is applied to the second induction coil 34, the second induction coil 34 generates a varying magnetic field concentrated in the second portion 24 of the cavity 20. Such varying magnetic field generated by the second induction coil 34 induces eddy currents in the second pantograph 14, causing the second pantograph to heat up. 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 inductively heated by the application of a varying magnetic field generated by either the first induction coil 32 or the second induction coil 34. In addition, the gap 15 provides thermally insulating the second pantograph 14 from the first pantograph 12, so that the rate of heat transfer between the first pantograph 12 and the second pantograph 14 is reduced compared to an induction heating element in which the first pantograph and the second pantograph are located adjacent to each other in direct thermal contact. As a result, providing a gap 15 between the first pantograph 12 and the second pantograph 14 provides selective heating of 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 provides selective heating of the second part 24 of the cavity 20 by the second pantograph 14 with minimal heating of the first part 22 cavities 20.

The first pantograph 12 and the second pantograph 14 may be heated simultaneously by simultaneously applying a varying electric current to the first induction coil 32 and the second induction coil 34. Alternatively, the first pantograph 12 and the second pantograph 14 may be heated independently or alternately by applying a varying electric current to the first induction coil 32 in the absence of current being supplied to the second induction coil 34 and by subsequently applying a varying electric current to the second induction coil 34 in the absence of current being supplied to the first induction coil 32. It is also provided that the varying electric current can be supplied to the first induction coil 32 and the second induction coil 34 in some order.

In fig. 2 is a schematic diagram of an induction heating element according to another embodiment of the present invention. The induction heating element shown in FIG. 2 is essentially identical to the induction heating element shown in FIG. 1, and the same reference numerals are used to describe the same features.

The induction heating element 10 in FIG. 2 is an elongated tubular element with a circular cross-section. The induction heating element 10 includes a first pantograph 12 and a second pantograph 14. The difference between the induction heating element 10 in FIG. 1 and induction heating element 10 in FIG. 2 is that the induction heating element 10 in FIG. 2 includes an intermediate element 16 located between the first pantograph 12 and the second pantograph 14. In the embodiment of FIG. 2 there is still a gap between the first pantograph 12 and the second pantograph 14, however the 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 is also attached to the end of the second pantograph 14. 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 indirectly connects the first pantograph 12 to the second pantograph 14. Advantageously, the indirect attachment of the first pantograph 12 to the second pantograph 14 allows the induction heating element to form an integral structure.

The intermediate element 16 contains thermal insulation material. The thermal insulation material is also electrical insulating. In this embodiment, the intermediate element 16 is formed from a polymeric material such as PEEK. As such, the intermediate member 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 inductively heated upon application of a varying magnetic field generated by either the first induction coil 32 or the second induction coil 34. In addition, , the intermediate element 16 provides thermal insulation of the second pantograph 14 from the first pantograph 12, so that the rate of heat transfer between the first pantograph 12 and the second pantograph 14 is reduced, compared with an induction heating element in which the first pantograph and the second pantograph are located adjacent to each other, in direct thermal contact. The spacer 16 may also further reduce the rate of heat transfer between the first pantograph 12 and the second pantograph 14 compared to the gap 15 of the induction heating element 10 shown in FIG. 1. As a result, the intermediate element 16 between the first pantograph 12 and the second pantograph 14 provides selective heating of 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 provides selective heating of the second part 24 of the cavity 20 by the second pantograph 14 with minimal heating first part 22 cavity 20.

In fig. 3-7 are schematic illustrations of an aerosol generating system in accordance with 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 an induction heating element 120 according to the present invention.

In fig. 3 and 4 show schematic diagrams of an induction heating element 120. The induction heating element 120 includes: a first pantograph 122, a second pantograph 124, a third pantograph 126, a first intermediate element 128, and a second intermediate element 130. The first intermediate element 128 is located 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 are the same. Each of the pantographs 122, 124, 126 is an elongated tubular pantograph defining an internal cavity. Each pantograph and its corresponding internal cavity are essentially cylindrical with a circular cross-section that is constant along the length of the pantograph. The internal cavity of the first pantograph 122 defines the first section 134. The internal cavity of the second pantograph 124 defines the second section 136. The internal cavity of the third pantograph defines the third section 138.

Likewise, the first intermediate element 128 and the second intermediate element 130 are identical. The intermediate elements 128, 130 are tubular, defining an internal cavity. Each intermediate element 128, 130 is essentially cylindrical with 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 system, the pantographs 122, 124, 126 and the intermediate elements 128, 130 form a tubular elongated cylindrical structure. This structure forms an induction heating element 120 in accordance with one embodiment of the present invention.

The elongated tubular induction heating element 120 includes an internal cavity 140. The induction heating element cavity 140 is defined by the internal cavities of the current collectors 122, 124, 126 and the internal cavities of the intermediate elements 128, 130. The induction heating element cavity 140 is configured to receive an aerosol generating segment of the product 200 , generating an aerosol, as described in more detail below.

The intermediate elements 128, 130 are formed from electrical insulating and thermal insulating material. As such, pantographs 122, 124, 126 are essentially electrically and thermally isolated from each other. The material of the intermediate elements 128, 130 is also essentially gas-tight. In this embodiment, the tubular induction heating element 120 is substantially gas-tight from the outer surface to the inner surface defining the induction heating element 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 body 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 the aerosol generating segment 210 of the aerosol generating article 200. Accordingly, the length and diameter of the device cavity 104 are 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 supply 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 supply 106, controller 108, and induction heating system 110 are located within the device housing 102. 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 the power supply 106 to the induction heating system 110. The controller 108 further includes a DC-AC converter including a Class D power amplifier, and is configured to supply varying current to the induction heating system 110. The controller 108 is also configured to control the recharging of the power supply 106 from the electrical connector 109. In addition, the controller 108 includes a puff sensor (not shown) configured to detect that a user is taking a puff on the aerosol generating article housed in the device cavity 104.

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

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

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

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

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

The induction heating system 110 further includes an induction heating element 120. The induction heating element 120 is located around the inner surface of the device cavity 104. In this embodiment, the device body 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 defined by the interior surface of the induction heating element 120.

The induction heating assemblies 112, 114, 116 are located around the induction heating element 120 such that the induction heating element 120 and the induction heating assemblies 112, 114, 116 are concentrically located around the device cavity 104. The first induction heating assembly 112 is located around the first susceptor 122 at the distal end of the device cavity 104. A second induction heating assembly 114 is located around a second susceptor 124 in the central portion of the device cavity 104. A third induction heating assembly 116 is located around a third susceptor 126 at the proximal end of the device cavity 104. It is contemplated that in some embodiments, flux concentrators may also extend into intermediate elements of the induction heating element to further deform the magnetic fields generated by the induction coils towards the current collectors.

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

The second induction coil 160 is connected to the controller 108 and the power supply 106, and the controller 108 is configured to supply a varying electrical current to the second induction coil 160. When the varying electrical current is supplied to the second induction coil 160, the second induction coil 160 generates a varying magnetic field that heats the second pantograph 124 by induction.

The first induction coil 170 is connected to the controller 108 and the power supply 106, and the controller 108 is configured to supply a varying electric current to the third induction coil 170. When the varying electric current is supplied to the third induction coil 170, the third induction coil 170 generates a varying magnetic field that heats the third pantograph 126 by induction.

The device body 102 also defines an air inlet 180 in close proximity to 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 defined through the device between the air inlet 180 and the air outlet at the distal end of the device cavity 104 to allow air from the air inlet 180 to be drawn into the device cavity 104.

The aerosol generating article 200 is generally provided in the form of a cylindrical rod having a diameter similar to the inner diameter of the device cavity 104. 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 cigarette paper wrapper 220.

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 takes a puff 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 device cavity 104. The aerosol generating segment 210 contains multiple aerosol generating substrates, including: a first aerosol generating substrate 212 at the distal end of the aerosol generating article 200, a second aerosol generating substrate 214 adjacent the first aerosol generating substrate 212, and a third substrate 216, which forms an aerosol, at the proximal end of the segment 210, which generates an aerosol, adjacent to the second substrate 216, which forms an aerosol. It should be understood that in some embodiments, two or more aerosol-forming substrates may be formed from the same materials. However, in this embodiment, each of the aerosol-forming substrates 212, 214, 216 is different. The first aerosol-forming substrate 212 comprises 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, for example, one or more aerosol-forming agents and water, such that heating the aerosol-forming substrate generates an aerosol with the desired organoleptic properties.

The proximal end of the first aerosol generating substrate 212 is open because it is not covered by the outer wrap 220. In this embodiment, air is able to be drawn into the aerosol generating segment 210 through the proximal end of the first aerosol generating 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, when the aerosol generating segment 210 of the aerosol generating article 200 is placed in the device cavity 104, the length of the first aerosol generating substrate 212 is such that the first aerosol generating substrate 212 extends from the distal end of the device cavity 104, through the first region 134 of the first pantograph 122 and 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 and 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 housed in the device cavity 104, the user can puff on 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 at 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 generating 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 induction coils of the induction heating system 110 in a predetermined sequence. The predetermined sequence involves applying a varying electrical current to the first induction coil 150 during the first puff from the user, then applying a varying electrical current to the second induction coil 160 during the second puff from the user after the first puff has been completed, and then applying a varying electrical current to the first induction coil 150. current to the third induction coil 170 during the third puff from the user after the second puff has been completed. On the fourth puff, the sequence begins again at the first induction coil 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 generating 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 induction coils in a different sequence or simultaneously, depending on the desired delivery of the aerosol to the user. In some embodiments, the user may be able to control the aerosol generating device to change the sequence.

Figure 8 shows an induction heating system according to another embodiment of the present invention. The induction heating system 300 includes two modular induction heating units, a first induction heating unit 310 and a second induction heating unit 360. The modular induction heating units 310, 360 are identical, independent units that are separately removable and replaceable within the induction heating system 300. The provision of such modular induction heating assemblies allows the induction heating system to be relatively inexpensive and easy to manufacture. The reason is that it may be easier to standardize the production of individual modular induction heating units rather than an entire induction heating system. Providing such modular induction heating units can also make it possible to easily customize an induction heating system.

The first induction heating assembly 310 generally includes a tubular first current collector 312, a tubular first induction coil 314, a tubular first flux concentrator 316, and a tubular first induction heating assembly housing 318.

The first pantograph 312 includes a tubular support body 320 formed from an electrically and thermally insulating material such as aluminum oxide, and a pantograph layer 322 on an inner surface of the tubular support body 320. Intermediate members 324 are provided at each end of the tubular support body 320, overlapping the ends pantograph layer 322. The intermediate members 324 are also formed from an electrical and thermal insulating material such as alumina.

The first induction coil 314 is located around the outer surface of the first susceptor 312 and extends substantially along the length of the first susceptor 312. Each end 326 of the first induction coil 312 extends through the first flux concentrator 316 and housing 318 to the outer surface of the first induction heating assembly 310, such that the first induction coil coil 314 may be connected to a power supply and supplied with varying current.

The first flux concentrator 316 is located around the outer surface of the tubular first induction coil 314 and extends along the ends of the first induction coil 314 and the first current collector 312, but not beyond the inner surface of the first current collector 312. Intermediate elements 324 are located between the first current collector 312 and the first flux concentrator 316 and electrically insulating the current collector layer of the first current collector 312 from the first flux concentrator 316 .

The housing 318 of the first induction heating assembly extends around the outer surface of the first flux concentrator 316, along the ends of the flux concentrator 316, and along the interior surface of the first flux concentrator 316. The housing 318 of the first induction heating assembly also extends over the intermediate members 324 of the first susceptor 312 such that the first susceptor 312, the first induction coil 314, and the first flux concentrator 316 are held together. Thus, the first current collector 312, the first induction coil 314, the first flux concentrator 316, and the first induction heating assembly housing 318 form a tubular block having an internal cavity that can accommodate an aerosol-forming substrate. The body 318 of the first induction heating unit is formed of electrical insulating and thermal insulating material. In this embodiment, the first induction assembly housing 318 is formed from a polymer, such as PEEK, that is injection molded over the first pantograph 312, the first induction coil 314, and the first flux concentrator 316.

The second induction heating assembly 360 generally includes a tubular second current collector 362, a tubular second induction coil 364, a tubular second flux concentrator 366, and a tubular second induction heating assembly housing 368.

The second pantograph 362 includes a tubular support body 370 formed from an electrically and thermally insulating material such as PEEK, and a pantograph layer 372 on the inner surface of the tubular support body 370. Intermediate members 374 are provided at each end of the tubular support body 370, overlapping the ends of the layer. 372 pantographs. The intermediate members 374 are also formed from an electrically and thermally insulating material, which in this embodiment is a ceramic material such as zirconium dioxide (ZrO2).

A second induction coil 364 is disposed around the outer surface of the second susceptor 362 and extends substantially along the length of the second susceptor 362. Each end 376 of the second induction coil 362 extends through the second flux concentrator 366 and housing 368 to the outer surface of the second induction heating assembly 360 such that the second induction coil 364 coil 364 can be connected to a power supply and supplied with varying current.

The second flux concentrator 366 is located around the outer surface of the tubular second induction coil 364 and extends along the ends of the second induction coil 364 and the second current collector 362, but not beyond the inner surface of the second current collector 362. Intermediate elements 374 are located between the second current collector 362 and the second flux concentrator 366 and electrically insulating the current collector layer of the second current collector 362 from the second flux concentrator 366 .

The body 368 of the second induction heating assembly extends around the outer surface of the second flux concentrator 366, along the ends of the flux concentrator 366, and along the interior surface of the second flux concentrator 366. The housing 368 of the second induction heating assembly also extends over the intermediate members 374 of the second pantograph 362 such that the second pantograph 362, the second induction coil 364, and the second flux concentrator 366 are held together. Thus, the second current collector 362, the second induction coil 364, the second flux concentrator 366, and the second induction heating assembly housing 368 form a tubular block having an internal cavity that can accommodate an aerosol-forming substrate. The body 368 of the second induction heating unit is formed of electrical insulating and thermal insulating material. In this embodiment, the body 368 of the second induction assembly is formed from a polymer, such as PEEK, which is injection molded over the second pantograph 362, the second induction coil 364, and the second flux concentrator 366.

A second induction heating assembly 360 is mounted on top of the first induction heating assembly 310 to form an induction heating system 300. The induction heating system 300 generally forms a tubular block defining an internal cavity 380 for receiving the aerosol-forming substrate.

When the second induction heating assembly 360 is installed on top of the first induction heating assembly 310, a gap exists between the first susceptor 312 and the second susceptor 362. The space includes an intermediate element 324, 374 from each of the first and second induction heating units 310, 360, as well as end portions of a flux concentrator 316, 366 and an induction heating unit body 318, 368 from each of the first and second induction heating units 310, 360. This spacing provides effective thermal and electrical insulation between the pantograph layer 322 of the first pantograph 312 and the pantograph layer 372 of the second pantograph 362.

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

Claims (49)

1. An induction heating element for an aerosol generating system, comprising: a first susceptor, which is a tubular susceptor and forms an internal cavity for receiving the aerosol-forming substrate; a second susceptor, which is a tubular susceptor and forms an internal cavity for containing the aerosol-forming substrate; a gap between the first pantograph and the second pantograph, the gap thermally insulating the first pantograph from the second pantograph. 2. The induction heating element according to claim 1, characterized in that the induction heating element further comprises an intermediate element located between the first pantograph and the second pantograph, the intermediate element comprising thermal insulation material for thermally insulating the first pantograph from the second pantograph. 3. An induction heating element according to claim 2, characterized in that the intermediate element contains electrical insulating material for electrically insulating the first pantograph from the second pantograph. 4. An induction heating element according to claim 2 or 3, characterized in that the intermediate element is a tubular intermediate element forming an internal cavity. 5. Induction heating element according to any one of paragraphs. 2-4, characterized in that the intermediate element is attached to the end of the first pantograph. 6. An induction heating element according to claim 5, characterized in that the intermediate element is attached to the end of the second pantograph. 7. Induction heating element according to any one of paragraphs. 1-6, characterized in that the first pantograph includes a tubular support body formed from a heat-insulating material and a pantograph layer on an inner surface of the tubular support body; the second pantograph contains a tubular support body formed from a heat-insulating material and a pantograph layer on the inner surface of the tubular support body. 8. Induction heating system containing: induction heating element according to any one of claims. 1-7; a first induction coil; And second induction coil, wherein the first induction coil is positioned relative to the induction heating element such that a varying electric current supplied to the first induction coil generates a varying magnetic field that heats the first current collector of the induction heating element; A the second induction coil is positioned relative to the induction heating element such that a varying electric current supplied to the second induction coil generates a varying magnetic field that heats the second current collector of the induction heating element. 9. Induction heating system according to claim 8, characterized in that the first induction coil is a tubular coil having an internal cavity, the first current collector being located within the internal cavity of the first induction coil; the second induction coil is a tubular coil having an internal cavity, the second current collector being located within the internal cavity of the second induction coil. 10. The induction heating system of claim 9, further comprising a flux concentrator located around the first induction coil and the second induction coil, the flux concentrator being configured to deform a changing magnetic field generated by the first induction coil in the direction of the first current collector and deformation of the changing magnetic field generated by the second induction coil in the direction of the second current collector. 11. The induction heating system according to claim 10, characterized in that part of the flux concentrator extends into the intermediate element between the first pantograph and the second pantograph. 12. Induction heating system according to claim 9, characterized in that it additionally contains: a first flux concentrator located around the first induction coil, wherein the first flux concentrator is configured to deform a changing magnetic field generated by the first induction coil in the direction of the first current collector; And a second flux concentrator located around the second induction coil, wherein the second flux concentrator is configured to deform the changing magnetic field generated by the second induction coil in the direction of the second current collector. 13. Induction heating system according to claim 12, characterized in that at least a portion of the first flux concentrator extends into an intermediate element between the first pantograph and the second pantograph; And a portion of the second flux concentrator extends into an intermediate element between the first pantograph and the second pantograph. 14. An aerosol generating device comprising an induction heating system according to any one of claims. 8-13. 15. An aerosol generating device containing: a device body defining a device cavity for receiving the aerosol-forming substrate; induction heating system containing: an induction heating element comprising: a first current collector located around the first portion of the device cavity; a second current collector located around the second portion of the device cavity; a gap between the first pantograph and the second pantograph, the gap thermally insulating the first pantograph from the second pantograph; a first induction coil disposed around at least a portion of the first pantograph and a first portion of the device cavity; a second induction coil disposed around at least a portion of the second pantograph and a second portion of the device cavity; a power supply connected to the induction heating system and configured to supply a varying electrical current to the first induction coil and the second induction coil, wherein, when a varying electric current is supplied to the first induction coil, the first induction coil generates a varying magnetic field that heats the first current collector; when a varying electric current is applied to the second induction coil, the second induction coil generates a varying magnetic field that heats the second current collector. 16. An aerosol generating system containing: aerosol generating product containing: a first aerosol-forming substrate; a second aerosol-forming substrate; aerosol generating device according to claim 15, wherein, when the aerosol-generating article is located in the device cavity, at least a portion of the first aerosol-generating substrate is located in the first portion of the device cavity, and at least a portion of the second aerosol-generating substrate is located in the second portion of the device cavity.