阅读说明：本技术 具有多个感受器的气溶胶生成系统 (Aerosol-generating system with multiple susceptors ) 是由 O·米罗诺夫 J·C·库拜特 T·李维尔 A·M·罗索尔 E·斯图拉 于 2018-08-09 设计创作，主要内容包括：本发明提供了一种具有气溶胶生成装置(100)的气溶胶生成系统,该气溶胶生成装置包括：具有室(120)的壳体(110),所述室的尺寸设定为接收气溶胶生成制品(10)的至少一部分；以及感应元件(130、930),所述感应元件围绕室(120)的至少一部分设置。气溶胶生成装置(100)还包括突出到室(120)中的多个细长感受器元件(180、960、980、1160、1180、1260、1280),所述多个细长感受器元件(180、960、980、1160、1180、1260、1280)在室的纵向方向上延伸并且彼此间隔开。气溶胶生成装置(100)还包括电源(140)和控制器(150),所述控制器连接到电感器线圈(130),并被配置成向电感器线圈(130)提供交变电流,使得在使用中,感应元件(130、930)能够被控制以按顺序在第一时段内提供具有第一频率的第一交变磁场接着在第二时段内提供具有第二频率的第二交变磁场。(The invention provides an aerosol-generating system having an aerosol-generating device (100) comprising: a housing (110) having a chamber (120) dimensioned to receive at least a portion of an aerosol-generating article (10); and an inductive element (130, 930) disposed around at least a portion of the chamber (120). The aerosol-generating device (100) further comprises a plurality of elongated susceptor elements (180, 960, 980, 1160, 1180, 1260, 1280) protruding into the chamber (120), the plurality of elongated susceptor elements (180, 960, 980, 1160, 1180, 1260, 1280) extending in a longitudinal direction of the chamber and being spaced apart from each other. The aerosol-generating device (100) further comprises a power supply (140) and a controller (150) connected to the inductor coil (130) and configured to provide an alternating current to the inductor coil (130) such that, in use, the inductive element (130, 930) can be controlled to sequentially provide a first alternating magnetic field having a first frequency for a first period of time followed by a second alternating magnetic field having a second frequency for a second period of time.)

1. An aerosol-generating system comprising:

an aerosol-generating device having,

a shell body, a plurality of first connecting rods and a plurality of second connecting rods,

a heating chamber defining a heating zone, the heating chamber being dimensioned to receive at least a portion of an aerosol-forming substrate within the heating zone,

an inductive element disposed around or adjacent to the heating zone,

a power supply for supplying power to the electronic device,

and a controller connected to the inductive element and configured to provide an alternating current to the inductive element to generate an alternating magnetic field within the heating zone,

wherein the inductive element is controllable to sequentially provide a first alternating magnetic field having a first frequency for a first period of time followed by a second alternating magnetic field having a second frequency for a second period of time.

2. An aerosol-generating system according to claim 1, wherein, in use, the first alternating magnetic field causes preferential heating of first susceptors located within the heating zone, and the second alternating magnetic field causes preferential heating of second susceptors located within the heating zone.

3. An aerosol-generating system according to claim 2, wherein the first susceptor is heated to a higher temperature than the second susceptor during the first period and the second susceptor is heated to a higher temperature than the first susceptor during the second period, or the second susceptor is heated to a higher temperature than the first susceptor during the first period and the first susceptor is heated to a higher temperature than the second susceptor during the second period.

4. An aerosol-generating system according to claim 1, claim 2 or claim 3, wherein the inductive element is controllable to provide three or more different alternating magnetic fields, each of the three or more magnetic fields having a different frequency, for three or more separate periods of time.

5. An aerosol-generating system according to claim 2, claim 3 or claim 4, wherein aerosol-generating device comprises the first susceptor and the second susceptor.

6. An aerosol-generating system according to claim 5, wherein the aerosol-generating device comprises a plurality of elongated susceptor elements protruding into the chamber, the plurality of elongated susceptor elements extending in a longitudinal direction of the chamber and being spaced apart from each other, the plurality of elongated susceptor elements comprising at least the first susceptor and the second susceptor.

7. An aerosol-generating system according to claim 6, wherein the plurality of elongate susceptor elements are substantially parallel to each other.

8. An aerosol-generating system according to any one of claims 5 to 7, wherein the first susceptor element, the second susceptor element or each of the plurality of elongate susceptor elements is detachably attached to the aerosol-generating device.

9. An aerosol-generating system according to claim 8, comprising the first susceptor element, the second susceptor element or the plurality of elongated susceptor elements and a base portion configured to be detachably attached to a housing of the aerosol-generating device, wherein the first susceptor element, the second susceptor element or the plurality of elongated susceptor elements are attached to the base portion such that the first susceptor element, the second susceptor element or the plurality of elongated susceptor elements protrude into the heating chamber when the base portion is detachably coupled to the housing.

10. An aerosol-generating system according to any preceding claim, further comprising an aerosol-generating article comprising the aerosol-forming substrate and dimensioned to be received by the heating chamber such that at least a portion of aerosol-forming substrate is within the heating zone.

11. An aerosol-generating system according to any of claims 2 to 4, further comprising an aerosol-generating article comprising the aerosol-forming substrate and dimensioned to be received by the heating chamber such that at least a portion of aerosol-forming substrate is within the heating zone, wherein the aerosol-generating article comprises the first susceptor and the second susceptor.

12. An aerosol-generating system according to any preceding claim, wherein the first susceptor has a first shape, a first cross-section, a first length dimension, a first width dimension and a first thickness dimension, and the second susceptor has a second shape, a second cross-section, a second length dimension, a second width dimension and a second thickness dimension, wherein at least one of the first shape and the second shape, the first cross-section and the second cross-section, the first length dimension and the second length dimension, the first width dimension and the second width dimension and the first thickness dimension and the second thickness dimension are different.

13. An aerosol-generating system according to any preceding claim, wherein the first susceptor is formed of a first material and the second susceptor is formed of a second material, wherein the first material has one or more material properties different from the second material, wherein the one or more properties comprise: the resistivity of the material and the permeability of the material.

14. An aerosol-generating system according to any preceding claim, wherein the inductive element is a single coil configured to provide both the first and second alternating magnetic fields, or wherein the inductive element comprises a first coil and a second coil, the first coil being actuatable to provide the first alternating magnetic field and the second coil being actuatable to provide the second alternating magnetic field.

15. A method of using an aerosol-generating system as defined in any preceding claim, the method comprising the steps of;

inserting the aerosol-generating article into a heating chamber of the aerosol-generating device such that at least a portion of an aerosol-forming substrate is located within the heating zone,

actuating the inductive element to provide a first alternating magnetic field having a first frequency for a first period of time to preferentially heat a first susceptor located within the heating zone for the first period of time, and

actuating the inductive element to provide a second alternating magnetic field having a second frequency for a second period of time to preferentially heat a second susceptor located within the heating zone for the second period of time,

heating a first portion of the aerosol-forming substrate by the first susceptor during the first period of time and heating a second portion of the aerosol-forming substrate by the second susceptor during the second period of time.

Technical Field

The present invention relates to aerosol-generating devices. In particular, the present invention relates to an aerosol-generating device having an induction heater for heating an aerosol-generating article using a susceptor. The invention also relates to an aerosol-generating system comprising such an aerosol-generating device in combination with an aerosol-generating article for use with an aerosol-generating device.

Background

Many electrically operated aerosol-generating systems have been proposed in the art in which an aerosol-generating device having an electric heater is used to heat an aerosol-forming substrate, such as a tobacco plug. One purpose of such aerosol-generating systems is to reduce known harmful smoke constituents of the type produced in conventional cigarettes by the combustion and pyrolytic degradation of tobacco. Typically, the aerosol-generating substrate is provided as part of an aerosol-generating article inserted into a chamber or cavity in an aerosol-generating device. In some known systems, in order to heat an aerosol-forming substrate to a temperature at which it is capable of releasing volatile components that can form an aerosol, a resistive heating element, such as a heating blade, is inserted into or around the aerosol-forming substrate when the aerosol-generating article is received in an aerosol-generating device. In other aerosol-generating systems, an inductive heater is used instead of a resistive heating element. The inductive heater typically comprises an inductor forming part of the aerosol-generating device and an electrically conductive susceptor element arranged such that it is thermally adjacent to the aerosol-forming substrate. During use, the inductor generates an alternating electromagnetic field to generate eddy currents and hysteresis losses in the susceptor element, thereby causing the susceptor element to heat up, thereby heating the aerosol-forming substrate.

In known systems having an inductor and an electrically conductive susceptor element, the susceptor element is typically fixed within a chamber of the aerosol-generating device and is configured such that it extends at least partially into the aerosol-generating article received in the chamber. The susceptor element heats the aerosol-forming substrate of the aerosol-generating article from inside when excited by the inductor coil. For example, the susceptor element may be arranged to pass through the aerosol-forming substrate of the aerosol-generating article when the aerosol-generating article is received in the chamber.

It is desirable to provide an aerosol-generating device having improved heat distribution when heating an aerosol-generating article.

Disclosure of Invention

According to a first aspect of the invention, there is provided an aerosol-generating system comprising: an aerosol-generating device having: a housing; a heating chamber defining a heating zone, the heating chamber being dimensioned to receive at least a portion of an aerosol-forming substrate therein; an inductive element disposed around or adjacent to the heating zone; a power source; and a controller connected to the inductive element and configured to provide an alternating current to the inductive element to generate an alternating magnetic field within the heating zone. The inductive element may be controlled to sequentially provide a first alternating magnetic field having a first frequency for a first period of time, followed by a second alternating magnetic field having a second frequency for a second period of time.

Advantageously, in use, the first alternating magnetic field may cause preferential heating of a first susceptor located within the heating zone and the second alternating magnetic field may cause preferential heating of a second susceptor located within the heating zone. The result of this may be that during a first period of time the first susceptor is heated to a higher temperature than the second susceptor and during a second period of time the second susceptor is heated to a higher temperature than the first susceptor. Thus, although both the first susceptor and the second susceptor may be heated simultaneously, the first alternating current may be more efficiently coupled to the first susceptor than to the second susceptor during the first period, with the result that the temperature of the first susceptor is greater than the temperature of the first susceptor during the first period. Alternatively, the second alternating magnetic field may cause preferential heating of a first susceptor located within the heating zone and the first alternating magnetic field may cause preferential heating of a second susceptor located within the heating zone. The result of this may be that during a first period of time the second susceptor is heated to a higher temperature than the first susceptor and during a second period of time the first susceptor is heated to a higher temperature than the second susceptor.

An alternating magnetic field having any particular frequency will produce different inductive behavior in different types of susceptors. For example, if the first and second susceptors have different physical dimensions, they may behave differently when located within an alternating magnetic field, and one or the other of the susceptors may heat to a higher temperature than the other of the susceptors. Also, if the first susceptor and the second susceptor are different in shape, the inductive behavior may be different. Also, the inductive behavior may be different if the first susceptor and the second susceptor are of different materials, e.g. different electrical resistivity or magnetic permeability.

The first susceptor may have a first shape, a first cross-section, a first length dimension, a first width dimension, and a first thickness dimension, the second susceptor may have a second shape, a second cross-section, a second length dimension, a second width dimension, and a second thickness dimension, wherein at least one of the first shape and the second shape, the first cross-section and the second cross-section, the first length dimension and the second length dimension, the first width dimension and the second width dimension, and the first thickness dimension and the second thickness dimension are different. One or more of the first shape and the second shape, the first cross section and the second cross section, the first length dimension and the second length dimension, the first width dimension and the second width dimension, and the first thickness dimension and the second thickness dimension may be different.

The first susceptor may have a shape selected from the list consisting of a rod, a needle, a tube, a blade, a sheet, or a specific shape, and the second susceptor may have a shape selected from the list consisting of a rod, a needle, a tube, a blade, a sheet, or a specific shape, the shape of the second susceptor being different from the shape of the first susceptor.

The first susceptor may have a cross-section selected from the list consisting of circular, oval, square, rectangular and triangular, and the second susceptor may have a cross-section selected from the list consisting of circular, oval, square, rectangular and triangular, the cross-section of the second susceptor being different from the shape of the first susceptor.

The first susceptor may be formed of a first material and the second susceptor may be formed of a second material, wherein the first material has one or more material properties different from the second material. The one or more characteristics may include a resistivity of the material and a permeability of the material.

The first susceptor may have a material selected from the list of ferrous alloys, stainless steel, aluminum, nickel alloys, graphite or carbon, the second susceptor may have a material selected from the list of ferrous alloys, stainless steel, aluminum, nickel alloys, graphite or carbon, the material of the second susceptor being different in shape from the first susceptor. The first and second susceptors may be formed of different compositions of the same alloy, for example different compositions of stainless steel, especially if the material properties such as resistivity or permeability are different due to the different compositions.

By choosing different parameters, the first and second susceptors may be optimized to heat in alternating magnetic fields of different frequencies. This may allow the aerosol-generating system to operate with two different susceptors, each susceptor being optimized to heat in an alternating magnetic field of a different frequency.

If the temperature of the first susceptor is sufficiently large to aerosolize material from the aerosol-forming substrate and the temperature of the second susceptor is not sufficiently large to aerosolize material from the aerosol-forming substrate when operating the aerosol-generating device, a portion of the aerosol-forming substrate located closer to the first susceptor may be preferentially aerosolized during the first period of time. Thus, sequential heating of different parts of the aerosol-forming substrate may be achieved by operating the device to generate a first alternating magnetic field having a first frequency to preferentially heat the first susceptor relative to the second susceptor, and subsequently to generate a second alternating magnetic field having a second frequency to preferentially heat the second susceptor relative to the second susceptor. Sequential heating may advantageously allow for optimization of aerosol delivery to a user over the duration of the smoking experience.

One of the first or second susceptor may be associated with a first aerosol-forming substrate and intended to heat the first aerosol-forming substrate, while the other of the first or second susceptor may be associated with a second aerosol-forming substrate and intended to heat the second aerosol-forming substrate.

In addition, the frequency of the alternating magnetic field may be adjusted between the first frequency and the second frequency to optimise heating of the aerosol-forming substrate during consumption.

A method of consuming an aerosol-generating article comprising an aerosol-forming substrate using an aerosol-generating system as described above may comprise the steps of: inserting an aerosol-generating article into a heating chamber of an aerosol-generating device such that at least a portion of the aerosol-forming substrate is located within the heating zone; actuating the inductive element to provide a first alternating magnetic field having a first frequency for a first period of time to preferentially heat a first susceptor located within the heating zone for the first period of time; and actuating the inductive element to provide a second alternating magnetic field having a second frequency for a second period of time to preferentially heat a second susceptor located within the heating zone for the second period of time. A first portion of the aerosol-forming substrate is heated by the first susceptor during a first period of time and a second portion of the aerosol-forming substrate is heated by the second susceptor during a second period of time.

In some embodiments, the inductive element may be controlled to provide three or more different alternating magnetic fields, each of the three or more magnetic fields having a different frequency, for three or more separate periods of time. Thus, three or more susceptors may be preferentially heated by each of three or more different alternating magnetic fields. Thus, sequential heating of three or more regions in the aerosol-forming substrate may be achieved. Furthermore, frequency modulation may allow for optimization of heating of three or four regions of the aerosol-forming substrate.

In some embodiments of the aerosol-generating system, the aerosol-generating device may comprise a first susceptor and a second susceptor. That is, the first susceptor and the second susceptor may be part of an aerosol-generating device. For example, such susceptors may extend into or be associated with a heating chamber of an aerosol-generating device. The aerosol-generating device may comprise a plurality of elongated susceptor elements protruding into the heating chamber, the plurality of elongated susceptor elements extending in a longitudinal direction of the heating chamber and being spaced apart from each other, the plurality of elongated susceptor elements comprising at least a first susceptor and a second susceptor.

The plurality of elongate susceptor elements may be substantially parallel to each other. Each of the first susceptor element, the second susceptor element or the plurality of elongated susceptor elements may be detachably attached to the aerosol-generating device. The aerosol-generating system may comprise a first susceptor element, a second susceptor element or a plurality of elongated susceptor elements, and a base portion configured to be detachably attached to a housing of the aerosol-generating device. The first susceptor element, the second susceptor element or the plurality of elongated susceptor elements may be attached to the base portion such that the first susceptor element, the second susceptor element or the plurality of elongated susceptor elements protrude into the heating chamber when the base portion is detachably coupled to the housing.

Preferably, the aerosol-generating system comprises an aerosol-generating device and an aerosol-generating article comprising the aerosol-forming substrate and dimensioned to be received by the heating chamber such that at least a portion of the aerosol-forming substrate is within the heating zone. The aerosol-generating article may comprise a first susceptor and a second susceptor. That is, the first and second susceptor may be part of an aerosol-generating article arranged to heat the aerosol-forming substrate.

Whether the susceptor is located in an aerosol-generating device or an aerosol-generating article, the first susceptor may have a first shape and the second susceptor may have a second shape different from the first shape. The first susceptor may have a first cross-section and the second susceptor may have a second cross-section different from the first cross-section. For example, the first susceptor may be shaped as an elongated blade having a rectangular cross-section and the second susceptor may be shaped as an elongated tube having a circular cross-section. The first susceptor may have a different size than the second susceptor.

The first susceptor may be formed of a first material and the second susceptor may be formed of a second material different from the first material. For example, the first material may be a magnetic material and the second material may be a non-magnetic material. The first material may have a first resistivity and the second material may have a second resistivity different from the first resistivity. The first susceptor may be an iron-based material, such as stainless steel, and the second susceptor may be a carbon or aluminum material.

The inductive element may be a single coil configured to provide both the first alternating magnetic field and the second alternating magnetic field. The controller may control the parameters to determine whether the single coil produces the first alternating magnetic field or the second alternating magnetic field.

The inductive element may comprise at least a first coil and a second coil. The first coil may be actuatable to provide a first alternating magnetic field and the second coil may be actuatable to provide a second alternating magnetic field. The controller may control whether the first coil or the second coil is actuated to generate the first alternating magnetic field or the second alternating magnetic field.

In an alternative aspect, an aerosol-generating device may comprise: a housing having a chamber sized to receive at least a portion of an aerosol-generating article; a plurality of elongate susceptor elements projecting into the chamber; an inductor coil disposed around at least a portion of the chamber; and a power supply and controller connected to the inductor coil and configured to provide an alternating current to the inductor coil such that, in use, the inductor coil produces an alternating magnetic field to heat the plurality of elongate susceptor elements and hence at least a portion of the aerosol-generating article received in the chamber. A plurality of elongated susceptor elements extend in the longitudinal direction of the chamber and are spaced apart from each other.

The aerosol-generating device of this alternative aspect may be used in an aerosol-generating system as described anywhere above. The following preferred features may relate to alternative aspects of the aerosol-generating system and aerosol-generating device described above.

As used herein, the term "longitudinal" is used to describe a direction along a major axis of an aerosol-generating device or aerosol-generating article, or a component of an aerosol-generating device or aerosol-generating article, and the term "transverse" is used to describe a direction perpendicular to the longitudinal direction. The heating chamber may sometimes be referred to simply as a "chamber". When referring to a chamber, the term "longitudinal" refers to the direction of insertion of the aerosol-generating article into the chamber, and the term "transverse" refers to a direction perpendicular to the direction of insertion of the aerosol-generating article into the chamber.

Generally, the chamber will have an open end into which the aerosol-generating article is inserted and a closed end opposite the open end. In such embodiments, the longitudinal direction is a direction extending between the open end and the closed end. In certain embodiments, the longitudinal axis of the chamber is parallel to the longitudinal axis of the aerosol-generating device. For example, the open end of the chamber is located at the proximal end of the aerosol-generating device. In other embodiments, the longitudinal axis of the chamber is at an angle to the longitudinal axis of the aerosol-generating device, for example transverse to the longitudinal axis of the aerosol-generating device. For example, the open end of the chamber is located along a side of the aerosol-generating device such that the aerosol-generating article may be inserted into the chamber in a direction perpendicular to the longitudinal axis of the aerosol-generating device.

As used herein, the term "proximal" refers to the user end or mouth end of the aerosol-generating device and the term "distal" refers to the end opposite the proximal end. When referring to a chamber or inductor coil, the term "proximal" refers to the area closest to the open end of the chamber and the term "distal" refers to the area closest to the closed end. The end of the aerosol-generating device or chamber may also be referred to with respect to the direction of airflow through the aerosol-generating device. The proximal end may be referred to as the downstream end and the distal end may be referred to as the upstream end.

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

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

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

As used herein, the term "aerosol-generating article" refers to an article comprising an aerosol-forming substrate capable of releasing volatile compounds that can form an aerosol. For example, the aerosol-generating article may be an article that generates an aerosol that can be inhaled directly by a user drawing or sucking on a mouthpiece at the proximal or user end of the system. The aerosol-generating article may be disposable. Articles comprising an aerosol-forming substrate, including tobacco, are known as cigarettes.

As used herein, the term "aerosol-generating device" refers to a device that interacts with an aerosol-generating article to generate an aerosol.

As used herein, the term "aerosol-generating system" refers to the combination of an aerosol-generating article as further described and illustrated herein and an aerosol-generating device as further described and illustrated herein. In the system, an aerosol-generating article and an aerosol-generating device cooperate to generate an inhalable aerosol.

As used herein, the term "elongated" refers to a component having a length that is greater than (e.g., twice as great as) its width and thickness.

As used herein, a "susceptor element" refers to an electrically conductive element that heats up when subjected to a changing magnetic field. This may be the result of eddy currents, hysteresis losses or both eddy currents and hysteresis losses induced in the susceptor element. During use, the susceptor element is located in thermal contact or in close thermal contact with an aerosol-forming substrate of an aerosol-generating article received in a chamber of an aerosol-generating device. In this way, the aerosol-forming substrate is heated by the susceptor element such that an aerosol is formed.

Advantageously, providing a plurality of elongate susceptor elements spaced apart from one another may promote uniform heating of the aerosol-forming substrate across the width of the aerosol-generating article. A uniform thermal distribution may result in more consistent aerosol characteristics and more efficient use of the aerosol-forming substrate. The use of different susceptors with differences (e.g. different sizes or shapes or materials) may allow for sequential heating of different parts of the aerosol-forming substrate, which may also facilitate more efficient use of the aerosol-forming substrate. By heating the aerosol-forming substrate more efficiently, the power required to heat the aerosol-forming substrate may be reduced relative to existing systems. This may improve the efficiency of the device according to the invention. This may result in a reduced battery size or may result in an increased battery life for a given battery size. This may facilitate a more compact arrangement.

The plurality of elongated susceptor elements may be spaced apart from each other in the transverse direction of the chamber. The plurality of elongate susceptor elements may be spaced apart from one another along a plane orthogonal to the longitudinal axis of the chamber.

By providing more uniform heating across the width of the aerosol-generating article, the width or thickness, or both, of each individual susceptor element may be reduced. This may advantageously reduce the force required to insert the aerosol-generating article into the chamber. Reducing the width or thickness, or both, of each individual susceptor element may reduce the amount of aerosol-forming substrate displaced during insertion, thereby reducing or eliminating the need to clean the chamber after use.

In addition, in embodiments in which the chamber of the aerosol-generating device and the aerosol-generating article have a circular cross-section, the required arrangement of the elongate susceptor element may reduce or prevent accidental rotation of the aerosol-generating article within the chamber, which may otherwise result in damage to the heater.

The use of induction heating has the following advantages: the heating element (susceptor element in this case) need not be electrically connected to any other component, thereby eliminating the need for solder or other bonding elements for the heating element. Furthermore, the inductor coil is provided as part of the aerosol-generating device, such that a simple, cheap and robust aerosol-generating article may be constructed. Aerosol-generating articles are typically disposable and are produced in much larger quantities than the aerosol-generating devices with which they operate. Thus, even if more expensive devices are required, reducing the cost of aerosol-generating articles, significant cost savings can be brought to the manufacturer and consumer.

Furthermore, the use of induction heating rather than a resistive coil may provide improved energy conversion as this may save energy losses associated with resistive coils, particularly losses due to contact resistance at the junction between the resistive coil and the power supply.

Advantageously, the use of an inductor coil rather than a resistive coil may extend the useful life of the aerosol-generating device, as the inductor coil itself experiences minimal heating during use of the aerosol-generating device.

The plurality of elongated susceptor elements may be arranged such that their respective longitudinal axes are at an angle to each other. That is, the plurality of elongate susceptor elements may be non-parallel. In a preferred embodiment, the plurality of elongated susceptor elements are substantially parallel to each other.

As used herein, the term "substantially parallel" means within plus or minus 10 degrees, preferably within plus or minus 5 degrees.

A plurality of elongated susceptor elements extend in the longitudinal direction of the chamber. That is, preferably, at least a portion of each susceptor element is substantially parallel to the longitudinal axis of the chamber. Advantageously, this facilitates insertion of at least a portion of the elongate susceptor element into the aerosol-generating article when the aerosol-generating article is inserted into the chamber. The plurality of elongated susceptor elements may be arranged such that their longitudinal axes are at an angle to, i.e. not parallel to, the longitudinal axis of the chamber. One or more of the plurality of elongated susceptor elements may be substantially parallel to the longitudinal axis of the chamber.

In a preferred embodiment, the plurality of elongated susceptor elements is substantially parallel to the longitudinal axis of the chamber. In this way, the susceptor element may be more easily inserted into the aerosol-generating article when the aerosol-generating article is inserted into the chamber.

The magnetic axis of the inductive element (e.g., inductor coil) may be at an angle, i.e., non-parallel, to the longitudinal axis of the chamber. In a preferred embodiment, the magnetic axis of the inductor coil is substantially parallel to the longitudinal axis of the chamber. This may facilitate a more compact arrangement. Preferably, at least a portion of each elongate susceptor element is substantially parallel to the magnetic axis of the inductor coil. This may promote uniform heating of the elongated susceptor element by the inductor coil. In a particularly preferred embodiment, the plurality of elongated susceptor elements are substantially parallel to each other and to the magnetic axis of the inductor coil, the longitudinal axis of the chamber.

One or more of the plurality of elongated susceptor elements may be at least partially coincident with the longitudinal axis of the chamber. For example, one or more of the plurality of elongate susceptor elements may be at an angle to the longitudinal axis of the chamber and may pass through the longitudinal axis of the chamber at a location along its length. Alternatively or additionally, one of the plurality of elongate susceptor elements may be parallel to the longitudinal axis of the chamber and centrally located within the chamber such that it extends along the longitudinal axis of the chamber.

In a preferred embodiment, the plurality of elongate susceptor elements are each spaced from the longitudinal axis of the chamber. In this way, the plurality of elongate susceptor elements are spaced apart from each other and from the longitudinal axis of the chamber. This may promote a uniform heat distribution across the entire width of the chamber and hence the aerosol-generating article received in the chamber.

Where the plurality of elongate susceptor elements are spaced from the longitudinal axis of the chamber, one or more of the plurality of elongate susceptor elements may be at a different distance from the longitudinal axis than one or more of the other elongate susceptor elements. This may allow the aerosol-generating device to more uniformly heat the asymmetric aerosol-forming substrate.

In a preferred embodiment, the plurality of elongated susceptor elements is equal to the longitudinal axis of the chamber. That is, at a given position along the length of the susceptor element, each of the plurality of elongated susceptor elements is equidistant from the longitudinal axis. This may facilitate uniform heating of a symmetrical aerosol-forming substrate by distributing the heat evenly across the width of the chamber. It may also avoid the need to insert the aerosol-generating article into a chamber having a particular orientation, which may be the case when the asymmetric aerosol-forming substrate, and the plurality of elongate susceptor elements, are at different distances from the longitudinal axis.

The plurality of elongated susceptor elements may comprise any suitable number of susceptor elements projecting into the chamber. For example, the number of susceptor elements may be selected based on the size of the chamber, the size, geometry and composition of the susceptor elements, and the size and composition of the aerosol-forming substrate intended for use with the aerosol-generating device. For example, the plurality of elongated susceptor elements may consist of two elongated susceptor elements which are spaced apart in the transverse direction of the chamber.

In certain embodiments, the plurality of elongated susceptor elements comprises three or more elongated susceptor elements. For example, the plurality of elongated susceptor elements may comprise three, four, five, six, seven, eight, nine, ten or more elongated susceptor elements. In such embodiments, the plurality of elongate susceptor elements may be spaced apart from each other in a single transverse direction such that they extend substantially along the same plane. This may allow for a more uniform heating of the aerosol-forming substrate than an arrangement consisting of two elongate susceptor elements. Alternatively, the plurality of elongate susceptor elements may be spaced apart in a first lateral direction of the chamber and in a second lateral direction of the chamber perpendicular to the first lateral direction. In this way a plurality of elongate susceptor elements are spaced apart over an area. This may in particular result in uniform heating of the aerosol-forming substrate of the aerosol-generating article received in the chamber.

When the plurality of elongated susceptor elements comprises three or more elongated susceptor elements, the three or more elongated susceptor elements may be spaced apart from each other in an irregular pattern, wherein the spacing between one or more pairs of adjacent susceptor elements is non-uniform. The plurality of elongated susceptor elements may be arranged in the following configuration: each susceptor element is positioned at a vertex of a polygon having sides of unequal length, having unequal corners, or having sides of unequal length and unequal corners. For example, the plurality of elongated susceptor elements may consist of four elongated susceptor elements located at the vertices of a rectangle, a trapezoid, a diamond, a kite shape, on a single circle or in another irregular configuration.

In a preferred embodiment, the plurality of elongated susceptor elements may be arranged in a regular pattern. As used herein, the term "regular pattern" is used to denote a pattern comprising an array of uniformly spaced elongate susceptor elements. For example, the elongated susceptor elements may be arranged in a regular striped pattern, a regular grid or square pattern, a regular brick pattern, a regular honeycomb or hexagonal pattern, or any other regular geometric pattern. The arrangement of the plurality of elongated susceptor elements may be selected based on the cross-sectional shape of the inductor coil, or vice versa.

The inductor coil may have a circular cross-sectional shape. The inductor coil may have a non-circular cross-sectional shape. For example, the inductor coil may have an elliptical, triangular, square, rectangular, trapezoidal, rhomboid, diamond, kite, pentagonal, hexagonal, heptagonal, octagonal, nonagonal, decagonal, or any other polygonal cross-sectional shape. The inductor coil may have a regular polygonal cross-sectional shape. For example, an equilateral triangular, square, regular pentagon, regular hexagon, regular heptagon, regular octagon, regular nonagon, or regular decagon cross-sectional shape.

The plurality of elongated susceptor elements may be arranged in a configuration in which each susceptor element is located at a vertex of a regular polygon. That is, at the vertices of equiangular and equilateral polygons. This may allow for more consistent heating over the entire area of the chamber. For example, where the plurality of elongate susceptor elements comprises three elongate susceptor elements, the elements may be arranged in a triangular configuration, such as an equilateral triangular configuration. Where the plurality of elongate susceptor elements comprises four elongate susceptor elements, the elements may be arranged in a square configuration.

A plurality of elongated susceptor elements project into the chamber. Preferably, each elongate susceptor element has a free end projecting into the chamber. Preferably, the free end is configured to be inserted into the aerosol-generating article when the aerosol-generating article is inserted into the chamber. Preferably, the free end of one or more of the plurality of elongate susceptor elements is tapered. This means that the cross-sectional area of a portion of the elongated susceptor element decreases in a direction towards the free end. Advantageously, the tapered free end facilitates insertion of the elongated susceptor element into the aerosol-generating article. Advantageously, the tapered free end may reduce the amount of aerosol-forming substrate displaced by the elongate susceptor element during insertion of the aerosol-generating article into the chamber. This may reduce the amount of cleaning required. In a preferred embodiment, each of the plurality of elongate susceptor elements is tapered at its free end. Preferably, each of the plurality of elongate susceptor elements tapers at its free end towards a tip.

The aerosol-generating device comprises a plurality of elongate susceptor elements projecting into the chamber. The aerosol-generating device may further comprise a non-elongate susceptor element within the chamber. The aerosol-generating device may further comprise one or more external susceptor elements. The outer susceptor element is configured to remain outside the aerosol-generating article received in the chamber. For example, the one or more outer susceptor elements may extend at least partially around the circumference of the aerosol-generating article when received in the chamber.

The elongate susceptor element may be formed of any material which can be inductively heated to a temperature sufficient to aerosolize the aerosol-forming substrate. Suitable materials for the elongate susceptor element include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, nickel-containing compounds, titanium, and composites of metallic materials. Preferred elongate susceptor elements comprise metal or carbon. Advantageously, each elongate susceptor element comprises or consists of a ferromagnetic material, such as ferritic iron, a ferromagnetic alloy (e.g. ferromagnetic steel or stainless steel), ferromagnetic particles and ferrites. Suitable elongate susceptor elements may be or may include aluminum. The elongated susceptor element preferably comprises more than 5%, preferably more than 20%, preferably more than 50% or more than 90% of ferromagnetic or paramagnetic material. The preferred elongated susceptor element may be heated to a temperature in excess of 250 degrees celsius.

One or more of the susceptor elements may be formed from a single layer of material. The single layer of material may be a layer of steel.

The elongated susceptor element may comprise a non-metallic core, wherein the metallic layer is disposed on the non-metallic core. For example, one or more of the elongated susceptor elements may comprise a metal track formed on the outer surface of a ceramic core or substrate.

One or more of the susceptor elements may be formed from a layer of austenitic steel. One or more layers of stainless steel may be disposed on the austenitic steel layer. For example, one or more of the susceptor elements may be formed of an austenitic steel layer having a stainless steel layer on each of its upper and lower surfaces.

The elongated susceptor elements may each comprise a first susceptor material and a second susceptor material. The first susceptor material may be arranged in close physical contact with the second susceptor material. The first susceptor material and the second susceptor material may be in intimate contact to form a unitary susceptor. In certain embodiments, the first susceptor material is stainless steel and the second susceptor material is nickel. One or more of the susceptor elements may have a two-layer construction. Such susceptor elements may be formed from a layer of stainless steel and a layer of nickel.

The intimate contact between the first susceptor material and the second susceptor material may be performed by any suitable means. For example, the second susceptor material may be plated, deposited, coated, clad or welded onto the first susceptor material. Preferred methods include electroplating, flow plating and cladding.

The second susceptor material may have a curie temperature below 500 ℃. The first susceptor material may be used primarily for heating the susceptor when the susceptor is placed in an alternating electromagnetic field. Any suitable material may be used. For example, the first susceptor material may be aluminum, or may be a ferrous material, such as stainless steel. The second susceptor material is preferably used primarily for indicating when the susceptor has reached a certain temperature, which is the curie-temperature of the second susceptor material. The curie temperature of the second susceptor material may be used to regulate the temperature of the entire susceptor during operation. Thus, the curie temperature of the second susceptor material should be below the ignition point of the aerosol-forming substrate. Suitable materials for the second susceptor material may include nickel and certain nickel alloys. The curie temperature of the second susceptor material may preferably be selected to be below 400 deg.c, preferably below 380 deg.c, or below 360 deg.c. Preferably, the second susceptor material is a magnetic material selected to have a curie temperature substantially the same as the desired maximum heating temperature. That is, preferably the curie temperature of the second susceptor material is about the same as the temperature to which the susceptor should be heated in order to generate an aerosol from the aerosol-forming substrate. For example, the curie temperature of the second susceptor material may be in the range of 200 ℃ to 400 ℃ or in the range of 250 ℃ to 360 ℃. In some embodiments it may be preferred that the first susceptor material is in the form of an elongated strip having a width between 3mm and 6mm and a thickness between 10 micrometers and 200 micrometers, and the second susceptor material is in the form of a discrete patch plated, deposited or welded onto the first susceptor material. For example, the first susceptor material may be an elongated strip of 430 grade stainless steel or an elongated strip of aluminum and the second susceptor material may be in the form of a patch of nickel having a thickness between 5 and 30 micrometers, which is deposited at a distance along the elongated strip of first susceptor material. The patch of second susceptor material may have a width of between 0.5mm and the thickness of the elongated strip. For example, the width may be between 1mm and 4mm, or between 2mm and 3 mm. The patch of second susceptor material may have a length of between 0.5mm and about 10mm, preferably between 1mm and 4mm or between 2mm and 3 mm.

In some embodiments it may be preferred that the first susceptor material and the second susceptor material are co-laminated in the form of elongated strips having a width between 3mm and 6mm and a thickness between 10 micrometers and 200 micrometers. Preferably, the first susceptor material has a greater thickness than the second susceptor material. The co-lamination may be formed by any suitable means. For example, the strip of the first susceptor material may be welded or diffusion bonded to the strip of the second susceptor material. Alternatively, a layer of the second susceptor material may be deposited or plated onto the strip of the first susceptor material.

In some embodiments, it may be preferred that each elongated susceptor has a width of between 3mm and 6mm and a thickness of between 10 micrometers and 200 micrometers, the susceptor comprising a core of a first susceptor material encapsulated by a second susceptor material. Thus, the susceptors may each comprise a strip of the first susceptor material that has been coated or coated by the second susceptor material. By way of example, the susceptor may comprise a strip of grade 430 stainless steel having a length of 12mm, a width of 4mm and a thickness of between 10 microns and 50 microns (e.g. 25 microns). Grade 430 stainless steel may be coated with a nickel layer of between 5 and 15 microns (e.g., 10 microns).

One or more of the elongated susceptor elements may comprise a first susceptor material, a second susceptor material and a protective layer. The first susceptor material may be arranged in close physical contact with the second susceptor material. The protective layer may be arranged in close physical contact with one or both of the first and second susceptor materials. The first susceptor material, the second susceptor material and the protective layer may be in intimate contact to form a unitary susceptor. The protective layer may be an austenitic steel layer. In certain embodiments, one or more of the elongated susceptor elements comprises a layer of steel, a layer of nickel, and a protective layer of austenitic steel. A protective layer of austenitic steel may be applied to the nickel layer. This may help protect the nickel layer from adverse environmental effects such as oxidation, corrosion and diffusion.

The plurality of elongate susceptor elements may be formed of the same material. Alternatively, one or more of the elongated susceptor elements may comprise one or several susceptor materials having susceptor characteristics different from at least one of the other susceptor elements. This may facilitate fine tuning of the thermal profile. This may also facilitate sequential heating of the susceptor elements. For example by forming the susceptor element from a material that is optimally heated at different alternating current frequencies.

The elongate susceptor element may have any suitable cross-section. For example, the elongated susceptor element may have a square, oval, rectangular, triangular, pentagonal, hexagonal or similar cross-sectional shape. The elongated susceptor element may have a planar or flat cross-sectional area.

The elongate susceptor element may be solid, hollow or porous. Preferably, each elongate susceptor element is solid. Each susceptor element is preferably in the form of a pin, rod, blade or plate. Each susceptor element preferably has a length of between 5mm and 15mm, for example between 6mm and 12mm, or between 8mm and 10 mm. Each susceptor element preferably has a width of between 1mm and 8mm, more preferably about 3mm to about 5 mm. Each susceptor element may have a thickness of about 0.01 mm to about 2 mm. If the susceptor element has a constant cross-section, for example a circular cross-section, its preferred width or diameter is between 1mm and 5 mm.

The plurality of elongated susceptor elements may have substantially the same length. That is, the length of each elongated susceptor element may be within 10%, preferably within 5%, of the length of the other elongated susceptor elements. The length of one or more of the plurality of elongated susceptor elements may be different from the length of the other elongated susceptor elements. The plurality of elongated susceptor elements may all have different lengths.

The plurality of elongated susceptor elements may have substantially the same width. That is, the width of each elongated susceptor element may be within 10%, preferably within 5%, of the width of the other elongated susceptor elements. The width of one or more of the plurality of elongated susceptor elements may be different from the width of the other elongated susceptor elements. The plurality of elongated susceptor elements may all have different widths.

The plurality of elongated susceptor elements may have substantially the same thickness. That is, the thickness of each elongated susceptor element may be within 10%, preferably within 5%, of the thickness of the other elongated susceptor elements. The thickness of one or more of the plurality of elongated susceptor elements may be different from the thickness of the other elongated susceptor elements. The plurality of elongated susceptor elements may all have different thicknesses.

The elongated susceptor elements may each have an outer protective layer, for example a ceramic protective layer or a glass protective layer. The outer protective layer may encapsulate the elongate susceptor element. The elongated susceptor elements may each comprise a protective coating formed of glass, ceramic or inert metal, which is formed on a core of susceptor material.

Preferably, the aerosol-generating device is portable. The aerosol-generating device may have a size comparable to a conventional cigar or cigarette. The aerosol-generating device may have an overall length of between about 30 millimeters and about 150 millimeters. The aerosol-generating device may have an outer diameter of between about 5mm and about 30 mm.

The aerosol-generating device housing may be elongate. The housing may comprise any suitable material or combination of materials. Examples of suitable materials include metals, alloys, plastics or composites containing one or more of those materials, or thermoplastics suitable for food or pharmaceutical applications, such as polypropylene, Polyetheretherketone (PEEK) and polyethylene. Preferably, the material is lightweight and not brittle.

The housing may comprise a mouthpiece. The mouthpiece may comprise at least one air inlet and at least one air outlet. The mouthpiece may comprise more than one air inlet. One or more of the air inlets may reduce the temperature of the aerosol prior to delivery to the user and may reduce the concentration of the aerosol prior to delivery to the user.

Alternatively, the mouthpiece may be provided as part of an aerosol-generating article.

As used herein, the term "mouthpiece" refers to a portion of an aerosol-generating device that is placed in the mouth of a user so as to directly inhale an aerosol generated by the aerosol-generating device from an aerosol-generating article received in a chamber of a housing.

The aerosol-generating device may comprise a user interface for activating the aerosol-generating device, for example a button for initiating heating of the aerosol-generating device or a display for indicating a status of the aerosol-generating device or the aerosol-forming substrate.

The aerosol-generating device comprises a power source. The power source may be a battery, such as a rechargeable lithium ion battery. Alternatively, the power supply may be another form of charge storage device, such as a capacitor. The power source may need to be recharged. The power source may have a capacity that allows storage of sufficient energy for one or more uses of the aerosol-generating device. For example, the power source may have sufficient capacity to allow continuous aerosol generation for a period of about six minutes, corresponding to the typical time taken to draw a conventional cigarette, or for a multiple of six minutes. In another example, the power source may have sufficient capacity to allow a predetermined number of puffs or discrete activations.

The power supply may be a DC power supply. In one embodiment, the power source is a DC power source 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 a DC power source in the range of about 2.5 watts to about 45 watts).

The power supply may be configured to operate at high frequencies. As used herein, the term "high frequency oscillating current" refers to an oscillating current having a frequency between 500kHz and 30 MHz. The high frequency oscillating current may have a frequency between about 1MHz to about 30MHz, preferably between about 1MHz to about 10MHz, and more preferably between about 5MHz to about 8 MHz.

The aerosol-generating device comprises a controller connected to the inductor coil and the power supply. The controller is configured to control the supply of power from the power source to the inductor. The controller may comprise a microprocessor, which may be a programmable microprocessor, a microcontroller or an Application Specific Integrated Chip (ASIC), or other electronic circuitry capable of providing control. The controller may include other electronic components. The controller may be configured to regulate the supply of current to the inductor coil. The current may be supplied to the inductor coil continuously after activation of the aerosol-generating device, or may be supplied intermittently, for example on a puff-by-puff basis. The circuit may advantageously comprise a DC/AC converter, which may comprise a class D or class E power amplifier.

One or more of the plurality of elongate susceptor elements may be fixedly attached to a housing of the aerosol-generating device. In such embodiments, for example, the fixedly attached elongate susceptor element may not be easily removed from the aerosol-generating device housing without damaging the susceptor element or the housing.

Advantageously, one or more of the plurality of elongate susceptor elements may be removably attached to the housing. For example, one or more of the plurality of elongate susceptor elements may be removably attached to the housing within the chamber. A part of the aerosol-generating device that is heated and may therefore exhibit a shorter lifetime is the susceptor element. Thus, providing a detachable elongated susceptor element allows the elongated susceptor element to be easily replaced and may extend the lifetime of the aerosol-generating device. Advantageously, providing a removable elongated susceptor element also facilitates cleaning of the susceptor element, replacement of the susceptor element, or both. It may also facilitate chamber cleaning. It may allow a user to selectively replace the susceptor element depending on the aerosol-generating article with which it is to be used. For example, certain susceptor elements may be particularly suitable or tuned for use with a particular type of aerosol-generating article or with an aerosol-generating article having a particular arrangement or type of aerosol-forming substrate. This may allow the performance of the aerosol-generating device used with the susceptor element to be optimized based on the type of aerosol-generating article.

A plurality of elongate susceptor elements may be removably attached to the housing. In such embodiments, the plurality of elongate susceptor elements may be removably attached to the housing by any suitable mechanism. For example by a threaded connection, by frictional engagement or by a mechanical connection such as a bayonet, clip or equivalent mechanism. The plurality of elongated susceptor elements may be removed from the aerosol-generating device alone or together with one or more of the other elongated susceptor elements.

The plurality of elongated susceptor elements may be attached to the housing directly or through one or more intermediate components. The plurality of elongate susceptor elements may be attached to a base portion configured to be removably attached to the aerosol-generating device. The elongate susceptor element may extend orthogonally from the base portion. This may facilitate insertion of the elongate susceptor element into the aerosol-generating device.

The base portion may be configured to be removably connected to the aerosol-generating device housing by at least one of an interference fit, a bayonet connector, and a threaded connector. The base portion may be configured to be removably attached to the housing by magnetic attachment. Advantageously, the magnetic attachment provides a simple and effective mechanism for detachably attaching the elongate susceptor element to the aerosol-generating device.

The base portion may comprise a permanent magnet and the aerosol-generating device may comprise a ferromagnetic material at the upstream end of the chamber. The base portion may comprise a ferromagnetic material and the aerosol-generating device may comprise a permanent magnet at the upstream end of the chamber. Advantageously, providing only one of the base portion and the aerosol-generating device with a permanent magnet may simplify and reduce the manufacturing cost of the aerosol-generating device.

The base portion may comprise a permanent magnet and the aerosol-generating device may comprise a permanent magnet at the upstream end of the chamber. Advantageously, providing both the base portion and the aerosol-generating device with permanent magnets may increase the strength of the magnetic attachment compared to embodiments containing only a single permanent magnet. Advantageously, the permanent magnets in the base portion and the permanent magnets in the aerosol-generating device may each be oriented such that, when the elongated susceptor element is inserted into the chamber, the absorption forces between the two permanent magnets result in the desired orientation of the elongated susceptor element.

In embodiments where the base portion is configured to be removably attached to the housing by a magnetic attachment, the aerosol-generating device may incorporate an extraction tool to remove the elongate susceptor element from the chamber. Preferably, the extraction tool is dimensioned to be inserted into the chamber and comprises a permanent magnet at one end of the extraction tool. The permanent magnet at the end of the extraction tool provides a stronger attraction force between the extraction tool and the substrate portion than between the substrate portion and the aerosol-generating device. Preferably, the extraction tool comprises one or several cavities for receiving one or more of the elongated susceptor elements when the extraction tool is inserted into the chamber.

Preferably, the housing comprises an opening at one end of the chamber for inserting the aerosol-generating article into the chamber. Preferably, the base portion is sized and shaped for inserting the elongate susceptor element and the base portion through the opening into the chamber. Advantageously, this may eliminate the need for a separate aperture to facilitate insertion of the elongate susceptor element into the chamber.

Preferably, the cross-sectional shape of the base portion is substantially the same as the cross-sectional shape of the chamber. The base portion may have a substantially circular cross-sectional shape.

The plurality of elongated susceptor elements are detachable from the base portion. Advantageously, this may facilitate repeated use of the base portion for a plurality of elongate susceptor elements. This may be desirable because deposits build up on the elongate susceptor element more quickly than on the substrate portion.

According to a second aspect of the invention, according to any embodiment discussed herein, there is provided a detachable susceptor assembly for an aerosol-generating device according to the first aspect of the invention, wherein the detachable susceptor assembly comprises a base portion configured to be detachably attached to a housing. The plurality of elongate susceptor elements are attached to the base portion such that the plurality of elongate susceptor elements protrude into the chamber when the base portion is detachably coupled to the housing. This may facilitate insertion of the elongate susceptor element into the aerosol-generating device. The base portion may be configured to be removably connected to the aerosol-generating device housing by at least one of an interference fit, a bayonet connector, and a threaded connector. The base portion may be configured to be removably attached to the housing by magnetic attachment. Advantageously, the magnetic attachment provides a simple and effective mechanism for detachably attaching the elongate susceptor element to the aerosol-generating device. The base portion may comprise a permanent magnet for detachably attaching the base portion to a housing of the aerosol-generating device.

The plurality of elongated susceptor elements are detachable from the base portion. Advantageously, this may facilitate repeated use of the base portion for a plurality of elongate susceptor elements. This may be desirable because deposits build up on the elongate susceptor element more quickly than on the substrate portion.

According to another aspect of the invention, there is provided an aerosol-generating system comprising an aerosol-generating device according to the alternative aspect of the invention and an aerosol-generating article having an aerosol-forming substrate and configured for use with the aerosol-generating device.

According to a further aspect of the invention, there is provided an aerosol-generating system comprising an aerosol-generating device and an aerosol-generating article having an aerosol-forming substrate and configured for use with the aerosol-generating device. An aerosol-generating device comprising: a housing having a chamber sized to receive at least a portion of an aerosol-generating article; an inductor coil disposed around at least a portion of the chamber; and a power supply and a controller connected to the inductor coil, wherein the aerosol-generating system further comprises a plurality of elongate susceptor elements positioned such that when the aerosol-generating article is received in the chamber, the plurality of elongate susceptor elements extend in a longitudinal direction of the chamber and are spaced apart from each other; and wherein the power supply and controller are configured to provide an alternating current to the inductor coil such that, in use, the inductor coil generates an alternating magnetic field to heat the plurality of elongate susceptor elements, and hence at least a portion of the aerosol-generating article.

The plurality of elongate susceptor elements may be positioned such that when the aerosol-generating article is received in the chamber, the plurality of elongate susceptor elements are spaced apart from each other in a transverse direction of the chamber.

A plurality of elongate susceptor elements may be provided as part of an aerosol-generating device. In such embodiments, the aerosol-generating device may be substantially as described herein with respect to the first aspect of the invention.

The plurality of elongate susceptor elements may be provided as part of an aerosol-generating article. The plurality of elongate susceptor elements may be in thermal proximity to the aerosol-forming substrate. A plurality of elongated susceptor elements may be embedded in an aerosol-forming substrate. The form, kind, distribution and arrangement of the plurality of elongated susceptor elements may be selected according to the needs of the user. The plurality of elongate susceptor elements may be arranged substantially longitudinally within the aerosol-generating article. This means that the length dimension of each elongate susceptor element may be arranged approximately parallel to the longitudinal direction of the aerosol-generating article, for example within plus or minus 10 degrees of parallel to the longitudinal direction of the aerosol-generating article.

Advantageously, by providing more uniform heating of the aerosol-forming substrate, the size of the individual susceptor elements may be reduced. When these are provided as part of an aerosol-generating article, the volume occupied by the smaller susceptor elements is reduced. This may allow for an increase in the amount of aerosol-forming substrate in an aerosol-generating article of a given size. This may allow for improved aerosol characteristics of the aerosol-generating article. It may allow the size of an aerosol-generating article to be reduced for a given amount of aerosol-forming substrate.

Where a plurality of elongate susceptor elements are provided as part of an aerosol-generating article, the elongate susceptor elements are preferably in the form of pins, rods, blades or plates. The length of each elongate susceptor element is preferably between 5mm and 15mm, for example between 6mm and 12mm, or between 8mm and 10 mm. The width of each susceptor element is preferably between 1mm and 8mm, preferably from about 3mm to about 5 mm. The thickness of each elongate susceptor element may be between 0.01 mm and 2mm, for example between 0.5mm and 2 mm. If the elongated susceptor element has a constant cross-section, for example a circular cross-section, its width or diameter is preferably between 1mm and 5 mm.

The elongate susceptor element may be formed from any material that is capable of being inductively heated to a temperature sufficient to generate an aerosol from the aerosol-forming substrate. Preferably the susceptor element comprises a metal or carbon. Suitable susceptor elements may comprise ferromagnetic materials such as ferritic iron or ferromagnetic steel or stainless steel. Suitable susceptor elements may be or include aluminum. A preferred susceptor element may be formed of 400 series stainless steel, such as grade 410 or grade 420 or grade 430 stainless steel. Different materials will consume different amounts of energy when positioned within magnetic fields having similar frequency and field strength values. Thus, parameters of the elongated susceptor element, such as material type, length, width and thickness, may be altered during manufacturing to provide the required power dissipation within a known magnetic field.

The plurality of susceptor elements may be provided as part of both the aerosol-generating device and the aerosol-generating article. For example, the plurality of elongate susceptor elements may comprise a plurality of elongate susceptor elements forming part of an aerosol-generating device and one or more elongate susceptor elements forming part of an aerosol-generating article.

The system of any of the aerosol-generating systems described above may be an electrically operated smoking system. The system may be a handheld aerosol-generating system. The aerosol-generating system may have a size comparable to a conventional cigar or cigarette. The smoking system may have an overall length of between about 30mm to about 150 mm. The smoking system may have an outer diameter of between about 5mm and about 30 mm.

The aerosol-generating system may be a combination of an aerosol-generating device and one or more aerosol-generating articles for use with the aerosol-generating device. However, the aerosol-generating system may comprise additional components, for example a charging unit for recharging an onboard power source in an electrically operated or electrically powered aerosol-generating device.

The aerosol-forming substrate of any aspect described herein may comprise nicotine. The nicotine-containing aerosol-forming substrate may be a nicotine salt substrate. The aerosol-forming substrate may comprise a plant-based material. The aerosol-forming substrate may comprise tobacco. The aerosol-forming substrate may comprise a tobacco-containing material comprising volatile tobacco flavour compounds that are released from the aerosol-forming substrate upon heating. Alternatively, the aerosol-forming substrate may comprise a non-tobacco material. The aerosol-forming substrate may comprise a homogenized plant-based material. The aerosol-forming substrate may comprise a homogenized tobacco material. Homogenized tobacco material may be formed by agglomerating particulate tobacco. In a particularly preferred embodiment, the aerosol-forming substrate comprises a gathered crimped sheet of homogenised tobacco material. As used herein, the term "embossed sheet" means a sheet having a plurality of substantially parallel ridges or corrugations.

The aerosol-forming substrate may comprise at least one aerosol-former. The aerosol former is any suitable known compound or mixture of compounds that facilitates the formation of a thick and stable aerosol when used and that is substantially 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 glycerin; esters of polyhydric alcohols, such as glycerol mono-, di-or triacetate; and fatty acid esters of mono-, di-or polycarboxylic acids, such as dimethyldodecanedioate and dimethyltetradecanedioate. Preferred aerosol formers are polyhydric alcohols or mixtures thereof, for example triethylene glycol, 1, 3-butanediol. Preferably, the aerosol former is glycerol. When present, the homogenized tobacco material may have an aerosol former content equal to or greater than 5% by weight on a dry weight basis, and preferably, between about 5% and about 30% by weight on a dry weight basis. The aerosol-forming substrate may comprise other additives and ingredients, such as flavourants.

In any of the above embodiments, the aerosol-generating article and the chamber of the aerosol-generating device may be arranged such that the aerosol-generating article is partially received within the chamber of the aerosol-generating device. The chamber of the aerosol-generating device and the aerosol-generating article may be arranged such that the aerosol-generating article is fully received within the chamber of the aerosol-generating device.

The aerosol-generating article may be substantially cylindrical in shape. The aerosol-generating article may be substantially elongate. The aerosol-generating article may have a length and a circumference substantially perpendicular to the length. The aerosol-forming substrate may be provided as an aerosol-forming segment containing the aerosol-forming substrate. The aerosol-forming section may be substantially cylindrical in shape. The aerosol-forming section may be substantially elongate. The aerosol-forming section may also have a length and a circumference substantially perpendicular to said length.

The aerosol-generating article may have an overall length of between about 30mm to about 100 mm. In one embodiment, the total length of the aerosol-generating article is about 45 mm. The aerosol-generating article may have an outer diameter of between about 5mm and about 12 mm. In one embodiment, the aerosol-generating article may have an outer diameter of about 7.2 mm.

The aerosol-forming substrate may be provided in aerosol-forming segments of between about 7mm to about 15mm in length. In one embodiment, the aerosol-forming section may have a length of about 10 mm. Alternatively, the aerosol-forming segment may have a length of about 12 mm.

The aerosol-generating segment preferably has an outer diameter approximately equal to the outer diameter of the aerosol-generating article. The aerosol-forming section may have an outer diameter of between about 5mm and about 12 mm. In one embodiment, the aerosol-forming section may have an outer diameter of about 7.2 mm.

The aerosol-generating article may comprise a filter rod. The filter rod may be located at the downstream end of the aerosol-generating article. The filter rod may be a cellulose ester filter rod. In one embodiment, the length of the filter rod is about 7 millimeters, but may have a length between about 5 millimeters and about 10 millimeters.

The aerosol-generating article may comprise an outer wrapper. Furthermore, the aerosol-generating article may comprise a separator between the aerosol-forming substrate and the filter rod. The separator may be about 18mm, but may be in the range of about 5mm to about 25 mm.

Features described in relation to one or more aspects may equally be applied to other aspects of the invention.

An aerosol-generating system as described herein may comprise any of the following features:

the aerosol-generating device may comprise: a housing having a chamber sized to receive at least a portion of an aerosol-generating article; an inductor coil disposed around at least a portion of the chamber; a plurality of elongated susceptor elements projecting into the chamber, the plurality of elongated susceptor elements extending in a longitudinal direction of the chamber and being spaced apart from each other; and a power supply and controller connected to the inductor coil and configured to provide an alternating current to the inductor coil such that, in use, the inductor coil generates an alternating magnetic field to heat the plurality of elongate susceptor elements and hence at least a portion of an aerosol-generating article received in the chamber.

The aerosol-generating device may comprise a plurality of elongate susceptor elements substantially parallel to one another.

The aerosol-generating device may comprise a plurality of elongate susceptor elements substantially parallel to the longitudinal axis of the chamber.

The aerosol-generating device may comprise a plurality of elongate susceptor elements each spaced from the longitudinal axis of the chamber.

The aerosol-generating device may comprise a plurality of elongate susceptor elements equidistant from the longitudinal axis of the chamber.

The aerosol-generating device may comprise a plurality of elongated susceptor elements comprising three or more elongated susceptor elements spaced apart in a first transverse direction of the chamber and in a second transverse direction of the chamber perpendicular to the first transverse direction.

The aerosol-generating device may comprise three or more elongate susceptor elements arranged in a regular pattern.

The aerosol-generating device may comprise a plurality of elongate susceptor elements, each being tapered at its free end.

The aerosol-generating device may comprise a plurality of elongate susceptor elements removably attached to the housing.

A removable susceptor assembly for an aerosol-generating device may comprise a plurality of elongate susceptor elements and a base portion configured to be removably attached to a housing of the aerosol-generating device, wherein the plurality of elongate susceptor elements are attached to the base portion such that when the base portion is removably coupled to the housing, the plurality of elongate susceptor elements protrude into the chamber.

An aerosol-generating system may comprise an aerosol-generating device as described anywhere herein and an aerosol-generating article having an aerosol-forming substrate, the aerosol-generating article being configured for use with the aerosol-generating device.

An aerosol-generating system may comprise an aerosol-generating device and an aerosol-generating article having an aerosol-forming substrate and configured for use with the aerosol-generating device, the aerosol-generating device comprising: a housing having a chamber sized to receive at least a portion of the aerosol-generating article; an inductor coil disposed around at least a portion of the chamber; and a power supply and a controller connected to the inductor coil, wherein the aerosol-generating system further comprises a plurality of elongate susceptor elements arranged such that, in use, the plurality of elongate susceptor elements extend in a longitudinal direction of the chamber and are spaced apart from each other; and wherein the power supply and controller are configured to provide an alternating current to the inductor coil such that, in use, the inductor coil generates an alternating magnetic field to heat the plurality of elongate susceptor elements and hence at least a portion of the aerosol-generating article.

The aerosol-generating system may comprise a plurality of elongate susceptor elements provided as part of the aerosol-generating device.

The aerosol-generating system may comprise a plurality of elongate susceptor elements provided as part of the aerosol-generating article.

Drawings

The invention will be further described, by way of example only, with reference to the accompanying drawings, in which:

figure 1 is a schematic cross-sectional illustration of an aerosol-generating system according to a first embodiment of the present invention;

figure 2 is a perspective side view of the aerosol-generating system of figure 1, further showing the inductor coil and susceptor element;

figure 3 is a perspective end view of the aerosol-generating system of figure 1;

figure 4 is an end view of the inductor coil and susceptor element of the aerosol-generating system of figure 1 with all other components omitted for clarity;

figure 5 is a schematic cross-sectional illustration of an aerosol-generating system according to a second embodiment of the present invention;

figure 6 is a perspective side view of the aerosol-generating system of figure 5, further showing the inductor coil and susceptor element;

figure 7 is a perspective end view of the aerosol-generating system of figure 5;

figure 8 is an end view of the inductor coil and susceptor element of the aerosol-generating system of figure 5 with all other components omitted for clarity;

figure 9 is a schematic cross-sectional illustration of an aerosol-generating system according to an embodiment of the invention;

figure 10 is a schematic end view showing one possible susceptor configuration of the aerosol-generating system of figure 9;

figure 11 is a schematic end view showing another possible susceptor configuration of the aerosol-generating system of figure 9; and

figure 12 is a schematic end view showing another possible susceptor configuration of the aerosol-generating system of figure 9.

Detailed Description

Figure 1 shows a schematic cross-sectional illustration of an aerosol-generating system according to a first embodiment of the present invention. The aerosol-generating system comprises an aerosol-generating device 100 according to the first embodiment and an aerosol-generating article 10 configured for use with the aerosol-generating device 100. Fig. 2, 3 and 4 show different views of the aerosol-generating device 100.

The aerosol-forming article 10 comprises an aerosol-forming section 20 at its distal end. The aerosol-forming section 20 comprises an aerosol-forming substrate, for example a plug comprising a tobacco material and an aerosol former, which may be heated to generate an aerosol.

The aerosol-generating device 100 comprises a device housing 110 defining a chamber 120 for receiving the aerosol-generating article 10. The proximal end of the housing 110 has an insertion opening 125 through which the aerosol-generating article 10 may be inserted into and removed from the chamber 120. The inductor coil 130 is arranged within the aerosol-generating device 100 between an outer wall of the housing 110 and the chamber 120. The inductor coil 130 is a helical inductor coil having a magnetic axis corresponding to the longitudinal axis of the chamber 120, in this embodiment, the longitudinal axis of the aerosol-generating device 100. As shown in fig. 1, inductor coil 130 is positioned adjacent a distal portion of chamber 120, and in this embodiment extends along a portion of the length of chamber 120. In other embodiments, inductor coil 130 may extend along all or substantially all of the length of chamber 120, or may extend along a portion of the length of chamber 120 and be positioned away from a distal portion of chamber 120. For example, inductor coil 130 may extend along a portion of the length of chamber 120 and be adjacent to a proximal portion of chamber 120. Inductor coil 130 is formed from a wire and has a plurality of turns or windings extending along its length. The wires may have any suitable cross-sectional shape, such as square, oval, or triangular. In this embodiment, the wire has a circular cross-section. In other embodiments, the wires may have a flat cross-sectional shape. For example, the inductor coil may be formed of a wire having a rectangular cross-sectional shape and wound such that a maximum width of the cross-section of the wire extends parallel to a magnetic axis of the inductor coil. Such a flat inductor coil may allow the outer diameter of the inductor, and thus the outer diameter of the aerosol-generating device, to be minimized.

The aerosol-generating device 100 further comprises an internal power source 140, such as a rechargeable battery, and a controller 150, such as a printed circuit board with circuitry, both located in the distal region of the housing 110. Both controller 150 and inductor coil 130 receive power from power source 140 via electrical connections (not shown) that extend through housing 110. Preferably, chamber 120 is separated by a fluid-tight partition from inductor coil 130 and the distal region of housing 110 containing power source 140 and controller 150. Thus, the electrical components within the aerosol-generating device 100 may remain separate from the aerosol or residue generated within the chamber 120 by the aerosol-generating process. This may also facilitate cleaning of the aerosol-generating device 100, as the chamber 120 may be completely empty simply by removing the aerosol-generating article. Such an arrangement may also reduce the risk of damage to the aerosol-generating device during insertion of the aerosol-generating article or during cleaning, as no potentially fragile elements are exposed within the chamber 120. Vents (not shown) may be provided in the walls of the housing 110 to allow air to flow into the chamber 120. Alternatively or additionally, the airflow may enter the chamber 120 at the opening 125 and flow along the length of the chamber 120 between the outer wall of the aerosol-generating article 10 and the inner wall of the chamber 120.

The aerosol-generating device 100 further comprises a susceptor assembly 160 located within the chamber 120. The susceptor assembly 160 comprises a base portion 170 and two elongated susceptor elements 180 attached to the base portion 170 and protruding into the chamber 120. Susceptor elements 180 are parallel to each other, to the longitudinal axis of chamber 120 and to the magnetic axis of inductor coil 130.

As best seen in fig. 2, 3 and 4, the susceptor elements 180 are spaced apart in the transverse direction and are evenly spaced apart from the longitudinal axis of the chamber 120. The susceptor element 180 is located within the portion of the chamber 120 surrounded by the inductor coil 130 such that it can be inductively heated by the inductor coil 130. Each susceptor element 180 is tapered towards its free end to form a tip. This may facilitate insertion of the susceptor element 180 into the aerosol-generating article received in the cavity. In this example, the base portion 170 is secured within the chamber 120 and the susceptor element 180 is secured to the base portion 170. In other examples, the base portion 170 may be removably coupled to the housing 110 to allow the susceptor assembly 160 to be removed from the chamber 120 as a single component. For example, the base portion 170 may be removably coupled to the housing 110 using a releasable clip (not shown), a threaded connection, or similar mechanical coupling.

When the aerosol-generating device 100 is actuated, a high frequency alternating current is passed through the inductor coil 130 to generate an alternating magnetic field within the distal portion of the chamber 120 of the aerosol-generating device 100. The magnetic field preferably fluctuates at a frequency between 1MHz and 30MHz, preferably between 2MHz and 10MHz, for example between 5MHz and 7 MHz. When the aerosol-generating article 10 is being positioned in the chamber 120, the susceptor element 180 is positioned within the aerosol-forming substrate 20 of the aerosol-generating article. The fluctuating field generates eddy currents within the susceptor elements 180, which are thus heated. Further heating is provided by hysteresis losses within the susceptor element 180. The heated susceptor element 180 heats the aerosol-forming substrate 20 of the aerosol-generating article 10 to a temperature sufficient to form an aerosol. The aerosol may then be drawn downstream through the aerosol-generating article 10 for inhalation by a user. Such actuation may be manual or may occur automatically in response to a user drawing on the aerosol-generating article 10 (e.g., by using a draw sensor).

The aerosol-generating device may further comprise a flux concentrator (not shown) located around the inductor coil 130 and formed of a material having a high relative magnetic permeability such that the magnetic field generated by the inductor coil 130 is attracted to and guided by the flux concentrator. In this manner, the flux concentrator may limit the extent to which the magnetic field generated by inductor coil 130 extends beyond housing 110, and may increase the density of the magnetic field within chamber 120. This may increase the current generated within the susceptor element to allow more efficient heating. Such flux concentrators may be made of any suitable material or materials having a high relative magnetic permeability. For example, the flux concentrator may be formed of one or more ferromagnetic materials, such as a ferrite material, a ferrite powder held in a binder, or any other suitable material including a ferrite material (e.g., ferritic iron, ferromagnetic steel, or stainless steel). The flux concentrator is preferably made of one or more materials having a high relative magnetic permeability. I.e., a material having a relative permeability of at least 5 when measured at 25 degrees celsius, e.g., at least 10, at least 20, at least 30, at least 40, at least 50, at least 60, at least 80, or at least 100. These example values may refer to the relative permeability of the flux concentrator material for frequencies between 6 and 8MHz and temperatures of 25 degrees celsius.

Figure 5 shows a schematic cross-sectional illustration of an aerosol-generating system according to a second embodiment of the present invention. The aerosol-generating system comprises an aerosol-generating device 200 according to the second embodiment and an aerosol-generating article 10 configured for use with the aerosol-generating device 200. Fig. 6, 7 and 8 show different views of the aerosol-generating device 200.

The aerosol-generating device 200 of the second embodiment is similar in construction and operation to the aerosol-generating device 100 of the first embodiment, and where the same features are present, like reference numerals have been used. However, unlike the aerosol-generating device 100 of the first embodiment, the aerosol-generating device 200 has an inductor assembly 260 comprising three elongate susceptor elements 280 attached to a base portion 270. The three susceptor elements 280 are arranged in a regular pattern. In particular, the susceptor elements 280 are arranged such that each susceptor element 280 is located at the apex of an equilateral triangle. In this way, the plurality of elongate susceptor elements 280 are spaced apart in a first lateral direction of the chamber and in a second lateral direction of the chamber perpendicular to the first lateral direction. This means that a plurality of elongated susceptor elements 280 are spaced apart across the area of the chamber 120 and each susceptor element extends along a different plane. This may result in more uniform heating of the aerosol-forming substrate of the aerosol-generating article received in the chamber.

Figure 9 shows a schematic cross-sectional illustration of an aerosol-generating system according to an embodiment of the invention. The embodiment illustrated in fig. 9 is similar to the embodiment described above with respect to fig. 1. Accordingly, components of the same system as described above with respect to fig. 1 have been given the same reference numerals and related description has not been repeated. Figure 10 shows an end view of the aerosol-generating device 100 of figure 9 revealing the configuration of the two susceptors 960, 980.

The embodiment of fig. 9 differs from the embodiment of fig. 1 in that the aerosol-generating device 100 comprises an inductive element 930 having two separate actuatable induction coils. The first induction coil 931 is configured to generate an alternating magnetic field having a frequency between 3 and 5MHz and the second induction coil 932 is configured to generate an alternating magnetic field having a frequency between 7 and 10 MHz. The first and second induction coils 931, 932 are linked to the controller 150 and are individually actuatable in sequence.

The aerosol-generating device further comprises two elongated susceptor elements 960, 980 arranged to protrude into the chamber. When the first induction coil 931 is actuated, the first susceptor element 960 is configured to heat more efficiently than the second susceptor element 980. Thus, when the first induction coil 931 is activated, the first susceptor element is configured to heat to a temperature greater than 300 degrees celsius, and when the first induction coil is activated, the second susceptor element is configured to heat to a temperature less than 300 degrees celsius. In use, this means that aerosol may be generated from the aerosol-forming substrate adjacent the first susceptor element, rather than from a portion of the aerosol-forming substrate adjacent the second susceptor element. Conversely, when second induction coil 932 is actuated, second susceptor element 980 is configured to heat more efficiently than first susceptor element 960. Thus, when the second induction coil 932 is actuated, the second susceptor element is configured to heat to a temperature greater than 300 degrees celsius, and when the second induction coil is activated, the first susceptor element is configured to heat to a temperature lower than 300 degrees celsius. In use, this means that aerosol may be generated from the aerosol-forming substrate adjacent the second susceptor element, rather than from a portion of the aerosol-forming substrate adjacent the first susceptor element.

By sequentially actuating the first susceptor element and the second susceptor element, a sequential heating of different parts of the aerosol-forming substrate may be achieved.

Many parameters may be altered to tune each susceptor element to operate more efficiently at any particular frequency of the alternating magnetic field. For example, the shape, size, permeability, and resistivity may all be varied to vary the manner in which eddy currents are generated within the susceptor and the heating efficiency.

As an example, figure 10 shows an end view of two susceptors 960, 980. These susceptors are shaped as elongated blades having a longitudinal dimension greater than a width dimension, which is greater than a thickness dimension. The longitudinal dimension is 10mm, the width dimension is 3mm and the thickness dimension is 1 mm. The first susceptor 960 may be formed from grade 430 stainless steel and the second susceptor may be formed from a graphite material.

Other examples of different configurations of susceptor elements are shown in figures 11 and 12. In fig. 11, a first susceptor 1160 is formed of an elongated blade of grade 430 stainless steel and a second susceptor 1180 is formed of an elongated tube of grade 430 stainless steel. In fig. 12, the first susceptor 1260 is formed from an elongated square cross-section bar of aluminum and the second susceptor 1280 is formed from an elongated circular cross-section bar of aluminum.

The skilled person can vary the size, shape and material to form different susceptor elements which produce different heating responses to alternating magnetic fields of different frequencies.

The above-described exemplary embodiments are not intended to limit the scope of the claims. Other embodiments consistent with the above-described exemplary embodiments will be apparent to those skilled in the art.