WO2023135195A1

WO2023135195A1 - Aerosol-generating device and extractor with shaped cavity

Info

Publication number: WO2023135195A1
Application number: PCT/EP2023/050606
Authority: WO
Inventors: Matteo Bologna; Marie FARINE; Jerome Uthurry
Original assignee: Philip Morris Products S.A.
Priority date: 2022-01-12
Filing date: 2023-01-12
Publication date: 2023-07-20
Also published as: KR20240129217A; CN118510411A

Abstract

An aerosol-generating device (10), extractor (30) for an aerosol-generating device, and an aerosol-generating system comprising a cavity (20) for receiving an aerosol-forming substrate (52), wherein the cavity (20) has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length. At least one of: the shape of the cross-section of the cavity (20) varies along the length of the cavity (20); the surface area of the cross-section of the cavity (20) varies along the length of the cavity (20); and a dimension of the cross-section of the cavity (20) varies along the length of the cavity (20).

Description

AEROSOL-GENERATING DEVICE AND EXTRACTOR WITH SHAPED CAVITY

The present disclosure relates to an aerosol-generating device, an extractor for an aerosolgenerating device, and an aerosol-generating system comprising an aerosol-generating device and an aerosol-generating article.

Some known aerosol-generating systems comprise an aerosol-generating device having a power supply, such as a battery, a controller, and a heating element for heating an aerosol-forming substrate. In some examples, the aerosol-forming substrate comprises a tobacco rod or a tobacco plug that is arranged in an aerosol-generating article. In use, the aerosol-generating article is inserted into a cavity of the aerosol-generating device, and the heating element either penetrates the aerosol-forming substrate or is arranged around the outside of the aerosol-forming substrate. Power is supplied to the heating element from the power supply to heat the aerosol-forming substrate, and volatile components of the aerosol-forming substrate are vaporised and released and condense to form an aerosol, which is inhalable by a user.

In some such aerosol-generating systems, the aerosol-generating article resembles a conventional cigarette, having a similar cylindrical stick like configuration. Such a resemblance to a conventional cigarette is often desirable for users of the aerosol-generating system that may be familiar with the ritual of smoking cigarettes. However, such a configuration for an aerosolgenerating article may not be optimal for the purposes of efficiently or evenly heating the aerosolforming substrate using a heating element in an aerosol-generating device. Such a configuration of an aerosol-generating article may result in regions of the aerosol-forming substrate being heated to a lower temperature than desired. This may also lead to excess aerosol-forming substrate being provided in the aerosol-generating article in order for the aerosol-generating system to generate the desired amount of aerosol.

It would be desirable to provide an aerosol-generating device that provides improved heat transfer from a heating element to an aerosol-forming substrate. It would be desirable to provide an aerosol-generating device that enables even heating across an aerosol-forming substrate. It would be desirable to provide an aerosol-generating device that enables a minimal mass of aerosol-forming substrate to be used to generate a desired amount of aerosol.

According to the present disclosure, there is provided an aerosol-generating device comprising a cavity for receiving an aerosol-forming substrate. The cavity may have: a first end. The cavity may have a second end opposite the first end. The cavity may have a length between the first end and the second end. The cavity may have a cross-section perpendicular to the length. The shape of the cross-section of the cavity may vary along the length of the cavity. The surface area of the cross-section of the cavity may vary along the length of the cavity. A dimension of the cross-section of the cavity may vary along the length of the cavity.

In some embodiments, the shape of the cross-section of the cavity varies along the length of the cavity. In some embodiments, the surface area of the cross-section of the cavity varies along the length of the cavity. In some embodiments, a dimension of the cross-section of the cavity varies along the length of the cavity. In some embodiments, one or more of: the shape of the cross-section of the cavity, the surface area of the cross-section of the cavity, and a dimension of the cross-section of the cavity varies along the length of the cavity.

Varying at least one of the shape of the cross section of the cavity and a dimension of the cavity along the length of the cavity may enable an aerosol-forming substrate to be provided in a first configuration, and subsequently be deformed when inserted into the cavity into a second configuration. In particular, where the aerosol-forming substrate is provided in an aerosolgenerating article, the aerosol-generating article may be provided with a configuration similar to a conventional cigarette, which may be familiar and desirable to a user, and subsequently the aerosol-forming substrate in the aerosol-generating article may be deformed when the aerosolgenerating article is inserted into the cavity of the aerosol-generating device to optimise the form of the aerosol-forming substrate to improve the transfer of heat from a heating element to the aerosolforming substrate. For example, the density of the aerosol-forming substrate may be modified by the deformation of the aerosol-forming substrate, minimising the peripheral portions of the aerosolforming substrate that are positioned far away from a heating element of the aerosol-generating device, which a difficult to heat to the desired temperature. Advantageously, optimising the form of the aerosol-forming substrate in the aerosol-generating device to improve the transfer of heat from a heating element to the aerosol-forming substrate may increase the amount of aerosol that can be generated from a particular mass of the aerosol-forming substrate. Accordingly, optimising the form of the aerosol-forming substrate in the aerosol-generating device may enable a desired amount of aerosol to be produced using a minimal mass of aerosol-forming substrate.

As used herein, an 'aerosol-generating device' refers to a device that interacts with an aerosol-forming substrate to generate an aerosol.

As used herein, an 'aerosol-forming substrate' relates to a substrate capable of releasing volatile compounds that may cool to form an aerosol. Such volatile compounds may be released by heating the aerosol-forming substrate. The aerosol formed by heating the aerosol-forming substrate may contain fewer known harmful constituents than would be produced by combustion or pyrolytic degradation of the aerosol-forming substrate.

The aerosol-forming substrate may be part of an aerosol-generating article. As used herein, an 'aerosol-generating article' refers to an article comprising an aerosolforming substrate that is capable of releasing volatile compounds that can form an aerosol. For example, an aerosol-generating article may be an article that generates an aerosol that is directly inhalable into a user's lungs through the user's mouth. An aerosol-generating article may be disposable. Preferably an aerosol-generating article is a heated aerosol-generating article, which is an aerosol-generating article comprising an aerosol-forming substrate that is intended to be heated rather than combusted in order to release volatile compounds that can form an aerosol. An aerosol-generating article may be, or may comprise, a tobacco stick.

The cavity of the aerosol-generating device may have any suitable shape and size. The cavity has a first end and a second end opposite the first end. The cavity has a length extending between the first end and the second end. The cavity also has a cross-section extending in a direction perpendicular to the length of the cavity. The cavity has a cross-section at each point along the length of the cavity.

Each cross-section of the cavity is formed by a plane extending in a direction perpendicular to the length of the cavity. Each cross-section of the cavity may have a width or diameter, a surface area, and a perimeter. As used herein, the width of a cross-section of the cavity is the distance between two opposite sides of the cavity on the plane forming the cross-section. As used herein, the perimeter of the cross-section of the cavity is the length of the line forming the boundary of the cavity on the plane forming the cross-section. As used herein, the surface area of a crosssection of the cavity is the size of the area defined by the perimeter of the cross-section.

A dimension of the cross-section of the cavity may vary along the length of the cavity. Preferably, the dimension of the cross-section of the cavity is a width of the cross-section of the cavity. Where the cross-section is circular, the dimension of the cross-section may be a diameter of the cross-section of the cavity. Where the cross-section is not circular, the dimension may be a major width of the cross-section of the cavity. The major width of a cross-section is the largest width of the cross-section. Where the cross-section is not circular, the dimension may be a minor width of the cross-section of the cavity. The minor width of a cross-section is the smallest width of the cross-section.

Where the shape of the cross-section of the cavity does not vary along the length of the cavity, the dimension that varies along the length of the cavity may be the same dimension of the cross-section of the cavity. For example, the dimension may be the minor width of the crosssection. The dimension that varies along the length of the cavity may extend in the same direction for each cross-section of the cavity. Where the shape of the cross-section of the cavity varies along the length of the cavity, the dimension of the cross-section of the cavity that varies along the length of the cavity may be the smallest width of the cross-section of the cavity. For example, where a cavity comprises a portion with a circular shaped cross-section and a portion with an oval shaped cross-section, the dimension for a circular shaped cross-section may be the diameter of the circle, and the dimension for the oval shaped cross-section may be the minor diameter of the oval. Where the shape of the cross-section of the cavity varies along the length of the cavity, the dimension that varies along the length of the cavity may be the largest dimension of the cross-section of the cavity.

In some embodiments, the dimension of the cross-section at the first end of the cavity is greater than the dimension of the cross-section at the second end of the cavity. Put in another way, the dimension of the cross-section at the second end of the cavity may be less than the dimension of the cross-section at the first end of the cavity. For example, the width of the crosssection at the first end of the cavity may be greater than the width of the cross-section at the second end of the cavity. In these embodiments, when an aerosol-forming substrate is inserted into the cavity at the first end and moved to the second end, the aerosol-forming substrate may be compressed as it moves from the first end to the second end. Compressing the aerosol-forming substrate may increase the density of the aerosol-forming substrate at the second end of the cavity, facilitating heat transfer from a heating element to all parts of an aerosol-forming substrate, which may advantageously lead to even heating across the aerosol-forming substrate.

In some embodiments, the surface area of the cross-section of the cavity varies along the length of the cavity. In some preferred embodiments, the surface area of the cross-section of the cavity at the first end of the cavity is greater than the surface area of the cross-section of the cavity at the second end of the cavity. Put in another way, the surface area of the cross-section of the cavity at the second end may be less than the surface area of the cross-section of the cavity at the first end. Advantageously, such a configuration may lead to compression of aerosol-forming substrate as it moves from the first end to the second end of the cavity, and facilitate heat transfer from a heating element to all parts of the aerosol-forming substrate.

Preferably, the perimeter of each cross-section of the cavity along the length of the cavity remains substantially constant. In other words, the length of the line forming the boundary of the cross-section of the cavity may remain substantially constant at each point along the length of the cavity. The perimeter of the cross-section at the first end of the cavity and the perimeter of the cross-section at the second end of the cavity may be the same. The cross-section at the first end of the cavity and the cross-section at the second end of the cavity may be isoperimetric.

Preferably, the perimeter of the cross-section of the cavity along the length of the cavity is substantially the same as the perimeter of a cross-section of the aerosol-forming substrate of the aerosol-forming substrate or the aerosol-generating article.

In some embodiments, a dimension of the cross-section at the second end of the cavity is greater than a dimension of the cross-section at the first end of the cavity in order to ensure that the perimeter of the cross-section at the second end of the cavity is the same as the perimeter of the cross-section at the first end of the cavity. For example, where the cross-section at the first end of the cavity is circular and the cross-section at the second end of the cavity is oval, the major diameter of the oval cross-section at the second end of the cavity may be greater than the diameter of the circular cross-section at the first end of the cavity.

Where an aerosol-generating article comprises an outer wrapper, such as an outer wrapper formed from paper, the outer wrapper may crimp or wrinkle when the aerosol-generating article is inserted into the cavity if the perimeter of the cross-section of the cavity at any point along the length of the cavity is less than the perimeter of a cross-section of the aerosol-generating article. Advantageously, providing the cavity with a cross-section having a perimeter along the length of the cavity that is substantially the same as the perimeter of a cross-section of the aerosol-generating article, or greater than the perimeter of a cross-section of the aerosol-generating article, may substantially prevent or inhibit crimping or wrinkling of the outer wrapper of an aerosol-generating article when an aerosol-generating article is inserted into the cavity. Advantageously, maintaining a substantially constant perimeter for the cross-section of the cavity along the length of the cavity may substantially prevent or inhibit crimping or wrinkling of the outer wrapper of an aerosolgenerating article when an aerosol-generating article is inserted into the cavity and moved from the first end to the second end.

Where the perimeter of a cross-section of the cavity at any point along the length of the cavity is less than the perimeter of a cross-section of an aerosol-generating article, and the aerosolgenerating article comprises an outer wrapper, the outer wrapper of the aerosol-generating article may comprise one or more cuts or slits to prevent or inhibit crimping and wrinkling of the outer wrapper when the aerosol-generating article is received in the cavity. The one or more cuts or slits may extend substantially in the direction of the length of the aerosol-generating article.

According to some preferred embodiments of the present disclosure, there is provided an aerosol-generating device comprising a cavity for receiving an aerosol-forming substrate. The cavity has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length. In these preferred embodiments, the surface area of the cross-section of the cavity varies along the length of the cavity; and the perimeter of the cross-section of the cavity remains substantially constant along the length of the cavity. In some of these preferred embodiments, the shape of the cross-section of the cavity varies along the length of the cavity.

The cross-section of the cavity at the first end may have any suitable shape. For example, the cross-section of the cavity at the first end may be substantially circular, elliptical, square, triangular or hexagonal. The cross-section of the cavity at the first end may have any polygonal shape. Where the shape of the cross-section of the cavity at the first end has corners, the corners may be rounded. Preferably, the cross-section of the cavity at the first end is substantially circular.

The cross-section of the cavity at the second end may have any suitable shape. For example, the cross-section of the cavity at the second end may be substantially circular, elliptical, square, triangular or hexagonal. The cross-section of the cavity at the second end may have any polygonal shape. Where the shape of the cross-section of the cavity at the second end has corners, the corners may be rounded.

In some embodiments, the shape of the cross-section of the cavity at the second end comprises a plurality of congruent shapes. In other words, the shape of the cross-section of the cavity at the second end is comprised of a plurality of shapes having the same shape and dimensions. In some preferred embodiments, the shape of the cross-section at the second end comprises two congruent circles. In some embodiments, the shape of the cross-section at the second end comprises two congruent ovals or ellipses. In some embodiments, the plurality of congruent shapes are partially overlapping. For example, where the shape of the cross-section of the cavity at the second end comprises two congruent circles, the shape of the cross-section of the cavity at the second end may form a figure of eight.

In some preferred embodiments, the shape of the cross-section of the cavity at the first end is substantially circular, and the shape of the cross-section of the cavity at the second end comprises two congruent circles.

In some embodiments, the shape of the cross-section of the cavity at the first end is substantially similar to the shape of the cross-section of the cavity at the second end. The shape of the cross-section of the cavity at the first end may be identical to the shape of the cross-section of the cavity at the second end.

In some embodiments, the shape of the cross-section of the cavity at the first end is different to the shape of the cross-section of the cavity at the second end. In some preferred embodiments, the shape of the cross-section at the first end is substantially circular, and the shape of the cross-section at the second end is substantially triangular, preferably forming an equilateral triangle. In some preferred embodiments, the shape of the cross-section at the first end is substantially circular, and the shape of the cross-section at the second end is substantially oval or elliptical. In some embodiments, the shape of the cross-section at the first end is substantially circular, and the shape of the cross-section at the second end is substantially square or rectangular.

Where the shape of the cross-section of the cavity comprises corners, the corners may be rounded. For example, where the shape of the cross-section of the cavity is triangular, the three corners of the triangle may be rounded. Rounding the corners of the cross-section of the cavity may facilitate cleaning of the cavity.

Where the shape of the cross-section of the cavity at the first end is different to the shape of the cross-section of the cavity at the second end, preferably the perimeter of the cross-section of the cavity remains substantially constant along the length of the cavity. In other words, the crosssection of the cavity at the first end and the cross-section of the cavity at the second end are isoperimetric.

In some embodiments, the cavity at the second end comprises one or more protrusions. The one or more protrusions may facilitate retention of the aerosol-forming substrate in the cavity. In some preferred embodiments, the one or more protrusions may comprise ridges. The ridges may extend substantially in the direction of the length of the cavity. The ridges may extend around the circumference of the cavity.

Preferably, the cross-section of the first end of the cavity may delimit the cross-section of the second end of the cavity. In other words, the cross-section of the second end of the cavity may fit entirely within the cross-section of the first end of the cavity. For example, where the first end of the cavity has a substantially circular cross-section and the second end of the cavity has a substantially triangular cross-section, the triangular cross-section of the second end of the cavity may be truncated at the corners by the circular cross-section of the first end of the cavity. The triangular cross-section of the second end of the cavity may have rounded corners, and each rounded corner may have a radius equal to the radius of the circular cross-section of the first end of the cavity.

Preferably, the cross-section of the first end of the cavity and the cross-section of the second end of the cavity are arranged coaxially on a central longitudinal axis.

The cavity may comprise a first end portion extending from the first end of the cavity. The cavity may comprise a second end portion extending from the second end of the cavity. The first end portion may extend to an intersection between the first end portion and the second end portion. The second end portion may extend to the intersection between the first end portion and the second end portion. The first end portion may terminate at an intersection between the first end portion and the second end portion. The second end portion may terminate at the intersection between the first end portion and the second end portion.

Preferably, the first end portion of the cavity and the second end of the cavity are arranged coaxially on a central longitudinal axis.

The shape of the cross-section of the cavity may be substantially the same between the first end and the intersection between the first end portion and the second end portion. The dimensions of the cross-section of the cavity may be substantially the same between the first end and the intersection between the first end portion and the second end portion. In other words, the crosssection of the cavity may remain constant between the first end and the intersection between the first end portion and the second end portion.

The shape of the cross-section of the cavity may be substantially the same between the second end and the intersection between the first end portion and second end portion. The dimensions of the cross-section of the cavity may be substantially the same between the second end and the intersection between the first end portion and the second end portion. In other words, the cross-section of the cavity may remain constant between the second end and the intersection between the first end portion and the second end portion.

The shape of the cross-section of the cavity may change at the intersection between the first end portion and the second end portion. The shape of the cross-section of the cavity may gradually change at the intersection between the first end portion and the second end portion. The dimensions of the cross-section of the cavity may change at the intersection between the first end portion and the second end portion. The dimensions of the cross-section of the cavity may gradually change at the intersection between the first end portion and the second end portion. Put in another way, the intersection between the first end portion and the second end portion may be chamfered. Such a gradual change, or chamfer, may facilitate deformation of the aerosol-forming substrate as it is moved from the first end of the cavity to the second end of the cavity.

The intersection between the first end portion and the second end portion may be an intersection region. The intersection region may extend along a portion of the length of the cavity. The shape of the cross-section of the cavity may vary over the length of the intersection region. The shape of the cross-section of the cavity may gradually vary over the length of the intersection region. A dimension of the cross-section of the cavity may vary over the length of the intersection region. A dimension of the cross-section of the cavity may gradually vary over the length of the intersection region. Advantageously, the cross-section of the cavity in the intersection region may vary gradually from that of the first end portion to the second end portion to facilitate deformation of aerosol-forming substrate inserted into the cavity at the first end and moved into the second end portion.

In some embodiments, the aerosol-generating device comprises a heating element. The heating element may take any suitable form.

In some embodiments, the heating element may comprise a resistive heating element. During use, an electrical current is supplied to the resistive heating element to generate heat by resistive heating.

Suitable materials for forming the resistive heating element include but are not limited to: semiconductors such as doped ceramics, electrically “conductive” ceramics (such as, for example, molybdenum disilicide), carbon, graphite, metals, metal alloys and composite materials made of a ceramic material and a metallic material. Such composite materials may comprise doped or undoped ceramics. Examples of suitable doped ceramics include doped silicon carbides. Examples of suitable metals include titanium, zirconium, tantalum and metals from the platinum group. Examples of suitable metal alloys include stainless steel, nickel-, cobalt-, chromium-, aluminium- titanium- zirconium-, hafnium-, niobium-, molybdenum-, tantalum-, tungsten-, tin-, gallium-, manganese- and iron-containing alloys, and super-alloys based on nickel, iron, cobalt, stainless steel, Timetai® and iron-manganese-aluminium based alloys.

In some embodiments, the resistive heating element comprises one or more stamped portions of electrically resistive material, such as stainless steel. Alternatively, the resistive heating element may comprise a heating wire or filament, for example a Ni-Cr (Nickel-Chromium), platinum, tungsten or alloy wire.

The heating element may comprise an electrically insulating substrate, wherein the resistive heating element is provided on the electrically insulating substrate. The electrically insulating substrate may be a ceramic material such as Zirconia or Alumina. Preferably, the electrically insulating substrate has a thermal conductivity of less than or equal to about 2 Watts per metre Kelvin.

In some embodiments, the heating element may comprise an inductive heating element. The inductive heating element may comprise a susceptor material. During use, a varying magnetic field is supplied to the inductive heating element, and the inductive heating element generates heat via eddy current induction and hysteresis losses on penetration of the inductive heating element with the varying magnetic field. In these embodiments, typically an inductor coil circumscribes the inductive heating element, and a varying electric current is supplied to the inductor coil to generate the varying magnetic field. An inductor coil may circumscribe the cavity. An inductor coil may circumscribe the second end portion of the cavity. As used herein, ‘susceptor material’ refers to a material that is capable of converting electromagnetic energy into heat. When a susceptor material is penetrated by an alternating electromagnetic field, the susceptor is heated. Heating of a susceptor element may be the result of at least one of hysteresis losses and eddy currents induced in the susceptor, depending on the electrical and magnetic properties of the susceptor material.

An inductive heating element may comprise any suitable material. The inductive heating element may be formed from any material that can be inductively heated to a temperature sufficient to release volatile compounds from the aerosol-forming substrate. Suitable materials for the inductive heating element include graphite, molybdenum, silicon carbide, stainless steels, niobium, aluminium, nickel, nickel containing compounds, titanium, and composites of metallic materials. The inductive heating element may preferably comprise a metal or carbon. Advantageously the inductive heating element may comprise or consist of a ferromagnetic material, for example, ferritic iron, a ferromagnetic alloy, such as ferromagnetic steel or stainless steel, ferromagnetic particles, and ferrite.

In some preferred embodiments, the heating element is configured to penetrate the aerosolforming substrate. In these embodiments, preferably the heating element extends into the cavity. Preferably, the heating element extends into the cavity at the second end. In these embodiments, the heating element may be an elongate heating element. The heating element may be bladeshaped. The heating element may be pin-shaped. The heating element may be cone-shaped.

In some embodiments, the heating element may be arranged to extend around an outer surface of an aerosol-forming substrate received within the cavity. The heating element may have a tubular shape. The heating element may comprise an electrically insulating substrate and at least one resistive heating track on the electrically insulating substrate. The electrically insulating substrate may comprise a flexible sheet. For example, the heating element may be formed in a flat state and then rolled into a tubular shape. The electrically insulating substrate may comprise a polyimide film. The at least one resistive heating track may comprise at least one metal or metal alloy. Examples of suitable metals include titanium, zirconium, tantalum and metals from the platinum group. Examples of suitable metal alloys include stainless steel, nickel-, cobalt-, chromium-, aluminium- titanium- zirconium-, hafnium-, niobium-, molybdenum-, tantalum-, tungsten-, tin-, gallium-, manganese- and iron-containing alloys, and super-alloys based on nickel, iron, cobalt, stainless steel, Timetai® and iron-manganese-aluminium based alloys.

Where the cavity comprises a first end portion and a second end portion, preferably the length of the heating element is substantially similar to the length of the second end portion of the cavity or less than the length of the second end portion of the cavity. The length of the heating element may be substantially the same as the length of the second end portion of the cavity. The length of the heating element may be less than the length of the second end portion of the cavity. Where the heating element extends into the cavity from the second end, preferably the heating element extends into the second end portion of the cavity. The heating element may extend into the second end portion of the cavity and terminate at or around the intersection between the first end portion and the second end portion. Where the heating element circumscribes the cavity, preferably the heating element circumscribes the second end portion of the cavity. The heating element may circumscribe the second end portion of the cavity and not circumscribe the first end portion of the cavity.

In some embodiments, the aerosol-generating device comprises a pin heating element extending into the cavity at the second end. The pin heating element may be an elongate heating element extending primarily in one direction and having a point at one end for puncturing an aerosol-forming substrate. The pin heating element may extend into the cavity substantially in the direction of the length of the cavity. The pin heating element may be configured to penetrate an aerosol-forming substrate received in the cavity.

In some preferred embodiments comprising a pin heating element, the shape of the crosssection at the first end of the cavity is substantially circular, and the shape of the cross-section at the second end of the cavity is substantially triangular. Preferably, the circular cross-section of the first end of the cavity delimits the triangular cross-section of the second end of the cavity. The circular cross-section of the first end of the cavity and the triangular cross-section of the second end of the cavity may be arranged coaxially on a central longitudinal axis. The pin heating element may extend along the central longitudinal axis.

Advantageously, providing a cavity with a second end having a substantially triangular cross-section may improve the transfer of heat from the pin heating element to the aerosol-forming substrate compared to a cavity with a second end having a cross-section that is substantially circular and having similar dimensions. This is because the proportion of aerosol-forming substrate that is arranged furthest from the pin heating element is reduced for a cavity having a triangular cross-section, compared to a cavity having a circular cross-section. Furthermore, the density of the aerosol-forming substrate is redistributed at the second end of the cavity, providing a higher density between the pin heating element and the flat sides of the triangular cross-section, and a lower density at the corners of the triangular cross-section, which is furthest from the pin heating element. Advantageously, providing a cavity having a second end having a triangular cross-section may enable the mass of aerosol-forming substrate required to generate a desired amount of aerosol to be reduced. In some preferred embodiments, the aerosol-generating device comprises two pin heating elements extending into the cavity at the second end. Each pin heating element may extend into the cavity substantially in the direction of the length of the cavity. Each pin heating element may be configured to penetrate an aerosol-forming substrate received in the cavity.

In some preferred embodiments having two pin heating elements, the shape of the crosssection at the first end of the cavity is substantially circular, and the shape of the cross-section at the second end of the cavity is substantially oval or elliptical. Preferably, the circular cross-section of the first end of the cavity delimits the oval or elliptical cross-section of the second end of the cavity. The circular cross-section of the first end of the cavity and the oval or elliptical cross-section of the second end of the cavity may be arranged coaxially on a central longitudinal axis. The pin heating element may extend parallel to the central longitudinal axis.

The oval or elliptical cross-section of the cavity at the second end may have a major diameter. Where the oval or elliptical cross-section of the cavity at the second end has a major diameter, the two pin heating elements may extend through the major diameter. Advantageously this arrangement of the pin heating elements may enable improved transfer of heat from the pin heating elements to an aerosol-forming substrate arranged at the second end of the cavity.

The oval or elliptical cross-section of the cavity at the second end may have two foci. Where the oval or elliptical cross-section has two foci, each pin heating element may extend through one of the foci. Advantageously this arrangement of the pin heating elements may enable improved transfer of heat from the pin heating elements to an aerosol-forming substrate arranged at the second end of the cavity.

In some preferred embodiments, the aerosol-generating device comprises a plurality of pin heating elements. Each of the plurality of pin heating elements may extend into the cavity at the second end. Where the aerosol-generating device comprises a plurality of heating elements, the shape of the cross-section of the cavity at the second end may comprise a plurality of congruent shapes. The number of pin heating elements may be the same as the number of congruent shapes comprising the shape of the cross-section of the cavity at the second end. In these embodiments, preferably each of the plurality of pin heating elements extends through a centre of one of the plurality of congruent shapes. For example, the aerosol-generating device may comprise two pin heating elements extending into the cavity at the second end, the shape of the cross-section of the cavity at the second end may comprise two congruent circles, and each of the pin heating elements may extend through a centre of one of the congruent circles.

In some preferred embodiments, the aerosol-generating device comprises a blade heating element extending into the cavity at the second end. The blade heating element may be an elongate heating element extending primarily in one plane and having a point at one end for puncturing an aerosol-forming substrate. The blade heating element may extend into the cavity substantially in the direction of the length of the cavity. The blade heating element may be configured to penetrate an aerosol-forming substrate received in the cavity.

In some preferred embodiments comprising a blade heating element, the shape of the cross-section at the first end of the cavity is substantially circular, and the shape of the crosssection at the second end of the cavity is substantially oval or elliptical. Preferably, the circular cross-section of the first end of the cavity delimits the oval or elliptical cross-section of the second end of the cavity. The circular cross-section of the first end of the cavity and the oval or elliptical cross-section of the second end of the cavity may be arranged coaxially on a central longitudinal axis. The blade heating element may extend along the central longitudinal axis.

Advantageously, providing a cavity with a second end having a substantially oval or elliptical cross-section may improve the transfer of heat from the blade heating element to the aerosolforming substrate compared to a cavity with a second end having a cross-section that is substantially circular and having similar dimensions. This is because the proportion of aerosolforming substrate that is arranged furthest from the blade heating element is reduced for a cavity having an oval or elliptical cross-section, compared to a cavity having a circular cross-section. Furthermore, the density of the aerosol-forming substrate is redistributed at the second end of the cavity, providing a higher density between the blade heating element and the long sides of the oval cross-section, and a lower density at the short sides of the oval cross-section, which are furthest from the pin heating element. Advantageously, providing a cavity having a second end having an oval or elliptical cross-section may enable the mass of aerosol-forming substrate required to generate a desired amount of aerosol to be reduced.

The oval or elliptical cross-section of the cavity at the second end may have a major diameter. Where the oval or elliptical cross-section of the cavity at the second end has a major diameter, the blade heating element may extend through the major diameter. Preferably, the blade heating element has a length extending substantially in the direction of the length of the cavity, and a width extending substantially in the direction of the major diameter of the cross-section of the cavity at the second end. Advantageously this arrangement of the blade heating element may enable improved transfer of heat from the blade heating elements to an aerosol-forming substrate arranged at the second end of the cavity.

The oval or elliptical cross-section of the cavity at the second end may have two foci. Where the oval or elliptical cross-section has two foci, the blade heating element may extend through both of the foci. Advantageously this arrangement of the blade heating element may enable improved transfer of heat from the blade heating element to an aerosol-forming substrate arranged at the second end of the cavity.

In some preferred embodiments, the aerosol-generating device further comprises an extractor. The extractor may facilitate extraction of an aerosol-forming substrate from the aerosolgenerating device. In these preferred embodiments, the extractor comprises a body defining the cavity for receiving the aerosol-forming substrate.

The extractor may comprise a tubular body. The tubular body of the extractor may define the cavity for receiving the aerosol-forming substrate. The first end of the cavity may be open for insertion of the aerosol-forming substrate into the cavity. The tubular body of the extractor may comprise an open first end, defining the open first end of the cavity. The second end of the cavity may be substantially closed. The tubular body of the extractor may comprise a substantially closed second end, defining the substantially closed second end of the cavity. The substantially closed second end of the extractor may comprise one or more openings to enable one or more heating elements to extend into the cavity from the second end.

Where the aerosol-generating device comprises a housing, the extractor may be movable relative to the housing. The extractor may be movable relative to the housing in any suitable manner. For example, the extractor may be rotatable, pivotable or slidable relative to the housing. Preferably, the extractor is slidable relative to the housing.

Where the aerosol-generating device comprises a heating element, preferably the extractor is movable relative to the heating element. In some preferred embodiments, the extractor is movable relative to the heating element between a first position and a second position. In the first position, the heating element may extend into the cavity. In the second position, the heating element may not extend into the cavity. The extractor may be movable relative to the heating element in any suitable manner. For example, the extractor may be rotatable, pivotable or slidable relative to the heating element. Preferably, the extractor is slidable relative to the heating element.

Preferably, the aerosol-generating device comprises a power supply. The power supply may be a DC power supply. In preferred embodiments, the power supply is a battery. The power supply may be a nickel-metal hydride battery, a nickel cadmium battery, or a lithium based battery, for example a lithium-cobalt, a lithium-iron-phosphate or a lithium-polymer battery. However, in some embodiments the power supply may be another form of charge storage device, such as a capacitor. The power supply may require recharging and may have a capacity that allows for the storage of enough energy for one or more user operations, for example one or more aerosolgenerating experiences. For example, the power supply may have sufficient capacity to allow for continuous heating of an aerosol-forming substrate for a period of around six minutes, corresponding to the typical time taken to smoke a conventional cigarette, or for a period that is a multiple of six minutes. In some embodiments, the power supply may have sufficient capacity to allow for continuous heating of an aerosol-forming substrate for a period of around four minutes, or for a period that is a multiple of four minutes. In another example, the power supply may have sufficient capacity to allow for a predetermined number of puffs or discrete activations of the heating element.

Preferably, the aerosol-generating device comprises a controller. The controller may be configured to control the supply of power from the power supply to the heating element. 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 comprise further electronic components.

Preferably, the aerosol-generating device comprises a housing. Where the aerosolgenerating device does not comprise an extractor, a tubular portion of the housing may at least partially define the cavity for receiving the aerosol-forming substrate. The housing may have a first end and a second end. The cavity may be arranged at the first end of the device.

The housing may be elongate. Preferably, the housing is cylindrical in shape. The housing may comprise any suitable material or combination of materials. Examples of suitable materials include metals, alloys, plastics or composite materials containing one or more of those materials, or thermoplastics that are suitable for food or pharmaceutical applications, for example polypropylene, polyetheretherketone (PEEK) and polyethylene. Preferably, the material is light and non-brittle. Preferably, the aerosol-generating device is portable. The aerosol-generating device may have a length of between approximately 70 millimetres and approximately 120 millimetres. The aerosolgenerating device may be a handheld device. In other words, the aerosol-generating device may be sized and shaped to be held in the hand of a user.

The aerosol-generating device may comprise at least one air inlet in fluid communication with the cavity. In embodiments in which the aerosol-generating device comprises a housing, preferably the housing at least partially defines the at least one air inlet. Preferably, the at least one air inlet is in fluid communication with the second end of the cavity. In embodiments in which the heating element extends into the cavity, preferably the heating element extends into the cavity from the second end of the cavity.

According to the disclosure, there is provided an extractor for extracting an aerosol-forming substrate from an aerosol-generating device. The extractor may comprise a body defining a cavity for receiving the aerosol-forming substrate. The cavity may have a first end. The cavity may have a second end opposite the first end. The cavity may have a length between the first end and the second end. The cavity may have a cross-section perpendicular to the length. At least one of: the shape of the cross-section of the cavity may vary along the length of the cavity; the surface area of the cross-section of the cavity may vary along the length of the cavity; and a dimension of the cross-section of the cavity may vary along the length of the cavity.

The cavity of the extractor may have any suitable shape and size. The cavity has a first end and a second end opposite the first end. The cavity has a length extending between the first end and the second end. The cavity also has a cross-section extending in a direction perpendicular to the length of the cavity. The cavity has a cross-section at each point along the length of the cavity.

Each cross-section of the cavity is formed by a plane extending in a direction perpendicular to the length of the cavity. Each cross-section of the cavity may have a width or diameter, a surface area, and a perimeter.

A dimension of the cross-section of the cavity may vary along the length of the cavity. Preferably, the dimension of the cross-section of the cavity is a width of the cross-section of the cavity. Where the cross-section is circular, the dimension of the cross-section may be a diameter of the cross-section of the cavity. Where the cross-section is not circular, the dimension may be a major width of the cross-section of the cavity. Where the cross-section is not circular, the dimension may be a minor width of the cross-section of the cavity.

Where the shape of the cross-section of the cavity does not vary along the length of the cavity, the dimension that varies along the length of the cavity may be the same dimension of the cross-section of the cavity. For example, the dimension may be the minor width of the crosssection. The dimension that varies along the length of the cavity may extend in the same direction for each cross-section of the cavity.

Where the shape of the cross-section of the cavity varies along the length of the cavity, the dimension of the cross-section of the cavity that varies along the length of the cavity may be the smallest width of the cross-section of the cavity. For example, where a cavity comprises a portion with a circular shaped cross-section and a portion with an oval shaped cross-section, the dimension for a circular shaped cross-section may be the diameter of the circle, and the dimension for the oval shaped cross-section may be the minor diameter of the oval. Where the shape of the cross-section of the cavity varies along the length of the cavity, the dimension that varies along the length of the cavity may be the largest dimension of the cross-section of the cavity.

In some embodiments, the dimension of the cross-section at the first end of the cavity is greater than the dimension of the cross-section at the second end of the cavity. Put in another way, the dimension of the cross-section at the second end of the cavity may be less than the dimension of the cross-section at the first end of the cavity. For example, the width of the cross- section at the first end of the cavity may be greater than the width of the cross-section at the second end of the cavity.

In some embodiments, the surface area of the cross-section of the cavity varies along the length of the cavity. In some preferred embodiments, the surface area of the cross-section of the cavity at the first end of the cavity is greater than the surface area of the cross-section of the cavity at the second end of the cavity. Put in another way, the surface area of the cross-section of the cavity at the second end may be less than the surface area of the cross-section of the cavity at the first end.

Preferably, the perimeter of the cross-section of the cavity remains substantially constant along the length of the cavity. In other words, the length of the line forming the boundary of the cross-section of the cavity may remain substantially constant along the length of the cavity. The perimeter of the cross-section at the first end of the cavity and the perimeter of the cross-section at the second end of the cavity may be the same. The cross-section at the first end of the cavity and the cross-section at the second end of the cavity may be isoperimetric. Preferably, the perimeter of the cross-section of the cavity is substantially the same as the perimeter of a cross-section of the aerosol-generating article, or greater than the perimeter of a cross-section of the aerosolgenerating article, along the length of the cavity.

According to some preferred embodiments of the present disclosure, there is provided an extractor for extracting an aerosol-forming substrate from an aerosol-generating device. The extractor may comprise a body defining a cavity for receiving the aerosol-forming substrate. The cavity may have a first end. The cavity may have a second end opposite the first end. The cavity may have a length between the first end and the second end. The cavity may have a cross-section perpendicular to the length. In these preferred embodiments, the surface area of the cross-section of the cavity varies along the length of the cavity; and the perimeter of the cross-section of the cavity remains substantially constant along the length of the cavity. In some of these preferred embodiments, the shape of the cross-section of the cavity varies along the length of the cavity. The cross-section of the cavity at the first end may have any suitable shape. For example, the cross-section of the cavity at the first end may be substantially circular, elliptical, square, triangular or hexagonal. The cross-section of the cavity at the first end may have any polygonal shape. Where the shape of the cross-section of the cavity at the first end has corners, the corners may be rounded. Preferably, the cross-section of the cavity at the first end is substantially circular.

The cavity may comprise a first end portion extending from the first end of the cavity. The cavity may comprise a second end portion extending from the second end of the cavity. The first end portion may extend to an intersection between the first end portion and the second end portion. The second end portion may extend to the intersection between the first end portion and the second end portion. The first end portion may terminate at an intersection between the first end portion and the second end portion. The second end portion may terminate at the intersection between the first end portion and the second end portion. Preferably, the first end portion of the cavity and the second end of the cavity are arranged coaxially on a central longitudinal axis.

The intersection between the first end portion and the second end portion may be an intersection region. The intersection region may extend along a portion of the length of the cavity. The shape of the cross-section of the cavity may vary over the length of the intersection region. The shape of the cross-section of the cavity may gradually vary over the length of the intersection region. A dimension of the cross-section of the cavity may vary over the length of the intersection region. A dimension of the cross-section of the cavity may gradually vary over the length of the intersection region. Advantageously, the cross-section of the cavity in the intersection region may vary gradually from that of the first end portion to the second end portion to facilitate deformation of aerosol-forming substrate inserted into the cavity at the first end and moved into the second end portion. According to the disclosure, there is provided an aerosol-generating system comprising: an aerosol-forming substrate; and an aerosol-generating device as described above.

In some preferred embodiments, there is provided an aerosol-generating system comprising: an aerosol-forming substrate; and an aerosol-generating device comprising a cavity for receiving the aerosol-forming substrate. The cavity of the aerosol-generating device has: a first end and an opposing second end; a length between the first end and the second end; and a crosssection perpendicular to the length. At least one of: the shape of the cross-section of the cavity varies along the length of the cavity; the surface area of the cross-section of the cavity varies along the length of the cavity; and a dimension of the cross-section of the cavity varies along the length of the cavity.

In some embodiments, the aerosol-forming substrate has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length.

Before the aerosol-forming substrate is received in the cavity of the aerosol-generating device, the shape of the cross-section of the aerosol-forming substrate may be substantially constant along the length of the aerosol-forming substrate. The shape of the cross-section of the aerosol-forming substrate may be substantially similar to the shape of the cross-section of the cavity of the aerosol-generating device at the first end of the cavity. Preferably, the shape of the cross-section of the aerosol-forming substrate is substantially circular.

Before the aerosol-forming substrate is received in the cavity of the aerosol-generating device, a dimension of the cross-section of the aerosol-forming substrate may be substantially constant along the length of the aerosol-forming substrate. A dimension of the cross-section of the aerosol-forming substrate may be substantially similar to the shape of the cross-section of the cavity at the first end of the cavity.

Preferably, the length of the aerosol-forming substrate is the same or less than the length of the cavity of the aerosol-generating device. The length of the aerosol-forming substrate may be one of: no more than 90% of the length of the cavity; no more than 80% of the length of the cavity; no more than 70% of the length of the cavity; no more than 60% of the length of the cavity; and no more than 50% of the length of the cavity.

Where the cavity comprises a first end portion and a second end portion, preferably the length of the aerosol-forming substrate is substantially similar to the length of the second end portion of the cavity or less than the length of the second end portion of the cavity. The length of the aerosol-forming substrate may be substantially the same as the length of the second end portion of the cavity. The length of the aerosol-forming substrate may be less than the length of the second end portion of the cavity.

The aerosol-generating device is configured to receive an aerosol-forming substrate. Preferably, the aerosol-forming substrate is a solid aerosol-forming substrate. Preferably, the aerosol-forming substrate comprises tobacco. Preferably, the aerosol-forming substrate is a solid aerosol-forming substrate comprising tobacco. The aerosol-forming substrate may comprise a tobacco-containing material containing volatile tobacco flavour compounds, which are released from the substrate upon heating.

The solid aerosol-forming substrate may comprise a plug of tobacco. The plug of tobacco may comprise, for example, one or more of: powder, granules, pellets, shreds, strands, strips or sheets containing one or more of: herb leaf, tobacco leaf, tobacco ribs, expanded tobacco and homogenised tobacco. As used herein, ‘homogenised tobacco material’ denotes a material formed by agglomerating particulate tobacco. Providing homogenised tobacco material may improve aerosol generation, the nicotine content and the flavour profile of the aerosol generated during heating of the aerosol-generating article. Specifically, the process of making homogenised tobacco involves grinding tobacco leaf, which more effectively enables the release of nicotine and flavours upon heating. Where the tobacco plug comprises homogenised tobacco material, the homogenised tobacco material may be in the form of a sheet. As used herein, ‘sheet’ denotes a laminar element having a width and length substantially greater than the thickness thereof.

The solid aerosol-forming substrate may comprise homogenised tobacco material. The solid aerosol-forming material may comprise shreds, strands or strips of homogenised tobacco material. The solid aerosol-forming substrate may comprise a sheet of homogenised tobacco material.

Sheets of homogenised tobacco material may be formed by agglomerating particulate tobacco obtained by grinding or otherwise comminuting one or both of tobacco leaf lamina and tobacco leaf stems. Sheets of homogenised tobacco material may comprise one or more of tobacco dust, tobacco fines and other particulate tobacco by-products formed during, for example, the treating, handling and shipping of tobacco. Sheets of homogenised tobacco material are preferably formed by a casting process of the type generally comprising casting a slurry comprising particulate tobacco and one or more binders onto a conveyor belt or other support surface, drying the cast slurry to form a sheet of homogenised tobacco material and removing the sheet of homogenised tobacco material from the support surface.

The solid aerosol-forming substrate may comprises a gathered sheet of homogenised tobacco material. As used herein, ‘gathered’ is used to describe a sheet that is convoluted, folded, or otherwise compressed or constricted substantially transversely to a longitudinal axis of the aerosol-generating article.

In some preferred embodiments, the aerosol-forming substrate comprises a gathered textured sheet of homogenised tobacco material. As used herein, ‘textured sheet’ denotes a sheet that has been crimped, embossed, debossed, perforated or otherwise deformed. Use of a textured sheet of homogenised tobacco material may advantageously facilitate gathering of the sheet of homogenised tobacco material to form the aerosol-forming substrate. The aerosol-forming substrate may comprise a gathered textured sheet of homogenised tobacco material comprising a plurality of spaced-apart indentations, protrusions, perforations or a combination thereof.

In a particularly preferred embodiment, the aerosol-forming substrate comprises a gathered crimped sheet of homogenised tobacco material. As used herein, ‘crimped sheet’ denotes a sheet having a plurality of substantially parallel ridges or corrugations. Preferably, the substantially parallel ridges or corrugations extend along or parallel to a longitudinal axis of the aerosolgenerating article. This advantageously facilitates gathering of the crimped sheet of homogenised tobacco material to form the aerosol-generating article. However, it will be appreciated that crimped sheets of homogenised tobacco material for inclusion in the aerosol-generating article may alternatively or in addition have a plurality of substantially parallel ridges or corrugations that are disposed at an acute or obtuse angle to the longitudinal axis of the aerosol-generating article.

The aerosol-forming substrate may comprise tobacco-containing material and non-tobacco containing material.

The aerosol-forming substrate may comprise an aerosol former. The aerosol-forming substrate may comprise a single aerosol former or a combination of two or more aerosol formers. As used herein, the term ‘aerosol former’ is used to describe any suitable known compound or mixture of compounds that, in use, facilitates formation of an aerosol and that is substantially resistant to thermal degradation at the operating temperature of the aerosol-generating article. Suitable aerosol-formers include, but are not limited to: polyhydric alcohols, such as propylene glycol, triethylene glycol, 1 ,3-butanediol and glycerine; esters of polyhydric alcohols, such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate. Preferred aerosol formers are polyhydric alcohols or mixtures thereof, such as propylene glycol, triethylene glycol, 1 ,3-butanediol and, most preferred, glycerine. The aerosol-forming substrate may have an aerosol former content of greater than 5 percent on a dry weight basis. The aerosol aerosol-forming substrate may have an aerosol former content of between approximately 5 percent and approximately 30 percent on a dry weight basis. The aerosol-forming substrate may have an aerosol former content of approximately 20 percent on a dry weight basis.

The aerosol-forming substrate preferably comprises homogenised tobacco material, an aerosol-former and water.

The homogenised tobacco material may be provided in sheets, which are one of folded, crimped, or cut into strips. In a particularly preferred embodiment, the sheets are cut into strips having a width of between about 0.2 millimetres and about 2 millimetres, more preferably between about 0.4 millimetres and about 1 .2 millimetres. In one embodiment, the width of the strips is about 0.9 millimetres.

In some preferred embodiments, the aerosol-generating system comprises an aerosolgenerating article comprising the aerosol-forming substrate.

The aerosol-generating article may comprise the aerosol-forming substrate and one or more additional components. For example, the aerosol-generating article may comprise at least one of: a filter, a hollow tube, and an aerosol-cooling element. Preferably, the aerosol-forming substrate and the one or more additional components are arranged end-to-end in the form of a rod. Preferably, the aerosol-generating article comprises a wrapper circumscribing the aerosol-forming substrate and the one or more additional components.

In some embodiments, the aerosol-generating article has a first end and an opposing second end. The aerosol-forming substrate may be arranged at the second end. The cavity of the aerosol-generating device may be configured to receive at least the aerosol-forming substrate at the second end of the aerosol-generating article. The aerosol-generating article may comprise a mouthpiece. The mouthpiece may be in the form of a filter, such as a cellulose acetate plug. The mouthpiece may be arranged at the first end of the aerosol-generating article, opposite the aerosolforming substrate.

Preferably, before insertion of the aerosol-generating article into the cavity of the aerosolgenerating device, the cross-section of the second end of the aerosol-generating article has substantially the same shape as the cross-section of the first end of the cavity of the aerosolgenerating device.

Preferably, before insertion of the aerosol-generating article into the cavity of the aerosolgenerating device, the cross-section of the second end of the aerosol-generating article has substantially the same dimensions as the cross-section of the first end of the cavity of the aerosolgenerating device.

The aerosol-generating article may have a total length of between approximately 30 millimetres and approximately 100 millimetres. The aerosol-generating article may have an external diameter of between approximately 5 millimetres and approximately 13 millimetres.

The aerosol-forming substrate may have a length of approximately 10 millimetres. The tobacco plug may have a length of approximately 12 millimetres. The diameter of the aerosolforming substrate may be between approximately 5 millimetres and approximately 12 millimetres.

Where the aerosol-generating article comprises a mouthpiece, preferably the mouthpiece is approximately 7 millimetres in length, but can have a length of between approximately 5 millimetres to approximately 10 millimetres.

In a preferred embodiment, the aerosol-generating article has a total length of between approximately 40 millimetres and approximately 50 millimetres. Preferably, the aerosol-generating article has a total length of approximately 45 millimetres. Preferably, the aerosol-generating article has an external diameter of approximately 7.2 millimetres.

Preferably, the aerosol-generating article has a similar form to a conventional cigarette, and particular a similar circular cross-section shape, with a similar external diameter. Such a form may be desirable for a user. Advantageously, varying the cross-section of the cavity of the aerosolgenerating device into which the aerosol-forming substrate of the aerosol-generating article is received may enable the form of the aerosol-generating article before insertion into the aerosolgenerating device to be maintained as similar to a conventional cigarette, while also enabling the form of the aerosol-forming substrate when inserted into the aerosol-generating device to be optimised for heating. Optimising the form of the aerosol-forming substrate for heating may enable the mass of aerosol-forming substrate to be minimised without reducing the amount of aerosol generated from the aerosol-forming substrate. Minimising the mass of aerosol-forming substrate in the aerosol-generating article, while maintaining the form of the aerosol-generating article before insertion into the cavity of the aerosol-generating device may require a reduction in the density of the aerosol-forming substrate in the aerosol-generating article before insertion into the cavity of the aerosol-generating device. Reducing the density of the aerosol-forming substrate in the aerosolgenerating article may also facilitate deformation of the aerosol-forming substrate when the aerosol-forming substrate is inserted into the cavity of the aerosol-generating device.

In some embodiments, the aerosol-generating article comprises an inductive heating element. The inductive heating element may comprise a susceptor material. During use, a varying magnetic field is supplied to the inductive heating element, and the inductive heating element generates heat via eddy current induction and hysteresis losses on penetration of the inductive heating element with the varying magnetic field. An inductive heating element may comprise any suitable material. The inductive heating element may be formed from any material that can be inductively heated to a temperature sufficient to release volatile compounds from the aerosol-forming substrate. Suitable materials for the inductive heating element include: graphite, molybdenum, silicon carbide, stainless steels, niobium, aluminium, nickel, nickel containing compounds, titanium, and composites of metallic materials. The inductive heating element may preferably comprise a metal or carbon. Advantageously the inductive heating element may comprise or consist of a ferromagnetic material, for example, ferritic iron, a ferromagnetic alloy, such as ferromagnetic steel or stainless steel, ferromagnetic particles, and ferrite.

The invention is defined in the claims. However, below there is provided a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein. EX1 . An aerosol-generating device comprising a cavity for receiving an aerosol-forming substrate, wherein the cavity has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length, and wherein at least one of: the shape of the cross-section of the cavity varies along the length of the cavity; the surface area of the cross-section of the cavity varies along the length of the cavity; and a dimension of the cross-section of the cavity varies along the length of the cavity.

EX2. An aerosol-generating device according to example EX1 , wherein the dimension of the cross-section at the first end of the cavity is greater than the dimension of the cross-section at the second end of the cavity.

EX3. An aerosol-generating device according to examples EX1 or EX2, wherein the surface area of the cross-section of the cavity varies along the length of the cavity.

EX4. An aerosol-generating device according to example EX3, wherein the surface area of the cross-section of the cavity at the first end of the cavity is greater than the surface area of the crosssection of the cavity at the second end of the cavity.

EX.5 An aerosol-generating device according to any one of examples EX 1 to EX4, wherein the perimeter of the cross-section of the cavity remains substantially constant along the length of the cavity. EX6. An aerosol-generating device according to any one of examples EX1 to EX5, wherein the shape of the cross-section at the first end is substantially circular, and the shape of the crosssection at the second end is substantially triangular.

EX7. An aerosol-generating device according to any one of examples EX1 to EX5, wherein the shape of the cross-section at the first end is substantially circular, and the shape of the crosssection at the second end is substantially oval or elliptical.

EX8. An aerosol-generating device according to any one of examples EX1 to EX5, wherein the shape of the cross-section at the first end is substantially circular, and the shape of the crosssection at the second end is substantially square or rectangular.

EX9. An aerosol-generating device according to any one of examples EX1 to EX5, wherein the shape of the cross-section of the cavity at the first end is substantially circular, and the shape of the cross-section of the cavity at the second end comprises a plurality of congruent shapes, and optionally wherein the plurality of congruent shapes are partially overlapping.

EX10. An aerosol-generating device according to any one of examples EX1 to EX5, wherein the shape of the cross-section of the cavity at the first end is substantially circular, and the shape of the cross-section of the cavity at the second end comprises two congruent circles, and optionally wherein the two congruent circles are partially overlapping.

EX11. An aerosol-generating device according to any one of examples EX1 to EX5, wherein the shape of the cross-section of the cavity at the first end is substantially circular, and the shape of the cross-section of the cavity at the second end comprises two congruent ovals or ellipses, and optionally wherein the two congruent ovals or ellipses are partially overlapping.

EX12. An aerosol-generating device according to any one of examples EX1 to EX11 , wherein the aerosol-generating device comprises a heating element.

EX13. An aerosol-generating device according to example EX12, wherein the heating element extends into the cavity.

EX14. An aerosol-generating device according to examples EX12 or EX13, wherein the heating element extends into the cavity at the second end.

EX15. An aerosol-generating device according to any one of examples EX12 to EX14, wherein the heating element is a pin heating element.

EX16. An aerosol-generating device according to any one of examples EX12 to EX14, wherein the heating element is a blade heating element.

EX17. An aerosol-generating device according to example EX6, wherein the aerosol-generating device further comprises a pin heating element extending into the cavity at the second end. EX18. An aerosol-generating device according to example EX17, wherein the pin heating element extends into the cavity substantially in the direction of the length of the cavity.

EX19. An aerosol-generating device according to example EX7, wherein the aerosol-generating device further comprises two pin heating elements extending into the cavity at the second end. EX20. An aerosol-generating device according to example EX19, wherein each pin heating element extends into the cavity substantially in the direction of the length of the cavity.

EX21. An aerosol-generating device according to examples EX19 or EX20, wherein the oval or elliptical cross-section of the cavity at the second end has a major diameter, and the two pin heating elements extend through the major diameter.

EX22. An aerosol-generating device according to any one of examples EX19 to EX21 , wherein the oval or elliptical cross-section of the cavity at the second end has two foci, and each pin heating element extends through one of the foci.

EX23. An aerosol-generating device according to example EX7, wherein the aerosol-generating device further comprises a blade heating element extending into the cavity at the second end. EX24. An aerosol-generating device according to example EX23, wherein the blade heating element extends into the cavity substantially in the direction of the length of the cavity.

EX25. An aerosol-generating device according to examples EX23 or EX24, wherein the oval or elliptical cross-section of the cavity at the second end has a major diameter, and the blade heating element heating elements extend through the major diameter.

EX26. An aerosol-generating device according to example EX25, wherein the blade heating element has a length extending substantially in the direction of the length of the cavity, and a width extending substantially in the direction of the major diameter of the cross-section of the cavity at the second end.

EX27. An aerosol-generating device according to any one of examples EX23 to EX26, wherein the oval or elliptical cross-section of the cavity at the second end has two foci, and the blade heating element extends through the two foci.

EX28. An aerosol-generating device according to example EX9, wherein the aerosol-generating device further comprises a plurality of pin heating elements extending into the cavity at the second end.

EX29. An aerosol-generating device according to example EX28, wherein the number of pin heating elements is the same as the number of congruent shapes comprising the shape of the cross-section of the cavity at the second end, and wherein each of the plurality of pin heating elements extends through a centre of one of the plurality of congruent shapes. EX30. An aerosol-generating device according to any one of examples EX1 to EX29, wherein the aerosol-generating device further comprises an extractor for extracting an aerosol-forming substrate from the aerosol-generating device, and wherein the extractor comprises a body defining the cavity for receiving the aerosol-forming substrate.

EX31. An aerosol-generating device according to example EX30, wherein the aerosol-generating device further comprises a housing, and wherein the extractor is movable relative to the housing. EX32. An aerosol-generating device according to any one of examples EX12 to EX29, wherein the aerosol-generating device further comprises an extractor for extracting an aerosol-forming substrate from the aerosol-generating device, wherein the extractor comprises a body defining the cavity for receiving the aerosol-forming substrate, and wherein the extractor is movable relative to the heating element.

EX33. An aerosol-generating device according to EX32, wherein the extractor is movable relative to the heating element between a first position in which the heating element extends into the cavity, and a second position in which the heating element does not extend into the cavity.

EX34. An extractor for extracting an aerosol-forming substrate from an aerosol-generating device, wherein the extractor comprises a body defining a cavity for receiving the aerosol-forming substrate, and wherein the cavity has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length, and wherein at least one of: the shape of the cross-section of the cavity varies along the length of the cavity; the surface area of the cross-section of the cavity varies along the length of the cavity; and a dimension of the cross-section of the cavity varies along the length of the cavity.

EX35. An extractor according to example EX34, wherein the dimension of the cross-section at the first end of the cavity is greater than the dimension of the cross-section at the second end of the cavity.

EX36. An extractor according to examples EX34 or EX35, wherein the surface area of the crosssection of the cavity varies along the length of the cavity.

EX37. An extractor according to example EX36, wherein the surface area of the cross-section of the cavity at the first end of the cavity is greater than the surface area of the cross-section of the cavity at the second end of the cavity.

EX38. An extractor according to any one of examples EX34 to EX37, wherein the perimeter of the cross-section of the cavity remains substantially constant along the length of the cavity EX39. An extractor according to any one of examples EX34 to EX38, wherein the shape of the cross-section at the first end is substantially circular, and the shape of the cross-section at the second end is substantially triangular.

EX40. An extractor according to any one of examples EX34 to EX38, wherein the shape of the cross-section at the first end is substantially circular, and the shape of the cross-section at the second end is substantially oval or elliptical.

EX41 . An extractor according to any one of examples EX34 to EX38, wherein the shape of the cross-section at the first end is substantially circular, and the shape of the cross-section at the second end is substantially square or rectangular.

EX42. An extractor according to any one of examples EX34 to EX38, wherein the shape of the cross-section of the cavity at the first end is substantially circular, and the shape of the crosssection of the cavity at the second end comprises a plurality of congruent shapes, and optionally wherein the plurality of congruent shapes are partially overlapping.

EX43. An extractor according to any one of examples EX34 to EX38, wherein the shape of the cross-section of the cavity at the first end is substantially circular, and the shape of the crosssection of the cavity at the second end comprises two congruent circles, and optionally wherein the two congruent circles are partially overlapping.

EX44. An extractor according to any one of examples EX34 to EX38, wherein the shape of the cross-section of the cavity at the first end is substantially circular, and the shape of the crosssection of the cavity at the second end comprises two congruent ovals or ellipses, and optionally wherein the two congruent ovals or ellipses are partially overlapping.

EX45. An aerosol-generating system comprising: an aerosol-forming substrate; and an aerosol-generating device according to any one of examples EX1 to EX33.

EX46. An aerosol-generating system comprising: an aerosol-forming substrate; and an aerosol-generating device comprising a cavity for receiving the aerosol-forming substrate, wherein the cavity has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length, wherein at least one of: the shape of the cross-section of the cavity varies along the length of the cavity; the surface area of the cross-section of the cavity varies along the length of the cavity; and a dimension of the cross-section of the cavity varies along the length of the cavity.

EX47. An aerosol-generating system according to example EX46, wherein the aerosol-forming substrate has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length, and wherein before the aerosol-forming substrate is received in the cavity of the aerosol-generating device: the shape of the cross-section of the aerosol-forming substrate is substantially constant along the length of the aerosol-forming substrate, and is substantially similar to the shape of the cross-section of the cavity at the first end of the cavity; and the surface area of the cross-section of the aerosol-forming substrate is substantially constant along the length of the aerosol-forming substrate, and is substantially similar to the surface area of the cross-section of the cavity at the first end of the cavity.

EX48. An aerosol-generating system according to example EX47, wherein the length of the aerosol-forming substrate is the same or less than the length of the cavity of the aerosol-generating device.

EX49. An aerosol-generating system according to example EX48, wherein the length of the aerosol-forming substrate is one of: no more than 90% of the length of the cavity; no more than 80% of the length of the cavity; no more than 70% of the length of the cavity; no more than 60% of the length of the cavity; and no more than 50% of the length of the cavity.

EX50. An aerosol-generating system according to any one of examples EX35 to EX49, wherein the aerosol-generating system comprises an aerosol-generating article comprising the aerosolforming substrate.

EX51. An aerosol-generating system according to example EX50, wherein the aerosol-generating article comprises at least one of: a filter, a hollow tube, and an aerosol-cooling element.

EX52. An aerosol-generating system according to example EX51 , wherein the aerosol-generating article comprises a wrapper circumscribing the aerosol-forming substrate and the at least one of: a filter, a hollow tube, and an aerosol-cooling element. EX53. An aerosol-generating system according to any one of examples EX50 to EX52, wherein the aerosol-forming substrate and the at least one of: a filter, a hollow tube, and an aerosol-cooling element are arranged end-to-end in the form of a rod.

EX54. An aerosol-generating system according to any one of examples EX45 to EX53, wherein the first end of the cavity of the aerosol-generating device is open for insertion of the aerosolforming substrate into the cavity.

EX55. An aerosol-generating system according to example EX45 to EX54, wherein the aerosolgenerating article has a first end and an opposing second end, and wherein the aerosol-forming substrate is arranged at the second end.

EX56. An aerosol-generating system according to example EX55, wherein the cavity of the aerosol-generating device is configured to receive at least the aerosol-forming substrate at the second end of the aerosol-generating article.

EX57. An aerosol-generating system according to any one of examples EX55 to EX56, wherein before insertion of the aerosol-generating article into the cavity of the aerosol-generating device, the cross-section of the second end of the aerosol-generating article has substantially the same shape as the cross-section of the first end of the cavity of the aerosol-generating device.

EX58. An aerosol-generating system according to any one of examples EX55 to EX57, wherein before insertion of the aerosol-generating article into the cavity of the aerosol-generating device, the cross-section of the second end of the aerosol-generating article has substantially the same dimensions as the cross-section of the first end of the cavity of the aerosol-generating device. EX59. An aerosol-generating system according to any one of examples EX55 to EX58, wherein before insertion of the aerosol-generating article into the cavity of the aerosol-generating device, the cross-section of the second end of the aerosol-generating article has a shape that is substantially different to the shape of the cross-section of the second end of the cavity of the aerosol-generating device.

EX60. An aerosol-generating system according to any one of examples EX55 to EX59, wherein before insertion of the aerosol-generating article into the cavity of the aerosol-generating device, the cross-section of the second end of the aerosol-generating article has a dimension that is substantially different to a dimension of the cross-section of the second end of the cavity of the aerosol-generating device.

Examples will now be further described with reference to the figures in which:

Figure 1 shows a schematic illustration of a cross-section through an aerosol-generating device according to an embodiment of the disclosure, wherein the aerosol-generating device comprises a cavity having a first end with a circular shaped cross-section and a second end with an oval shaped cross-section;

Figure 2 shows a schematic illustration of a cross-section through a portion of the aerosolgenerating device of Figure 1 , rotated 90 degrees compared to Figure 1 ;

Figure 3 shows a schematic illustration of a plan view of the aerosol-generating device of Figure 1 , looking into the cavity of the device from an open first end of the cavity;

Figure 4 shows a schematic illustration of an aerosol-generating article comprising an aerosol-forming substrate, the aerosol-generating article being suitable for use with the aerosolgenerating device of Figure 1 to form an aerosol-generating system according to an embodiment of the disclosure;

Figure 5 shows a schematic illustration of an aerosol-generating system comprising the aerosol-generating device of Figure 1 and the aerosol-generating article of Figure 4, in which a portion of the aerosol-generating article is received in the cavity of the aerosol-generating device;

Figure 6 shows a schematic illustration of a cross-section through an aerosol-generating device according to another embodiment of the disclosure, wherein the aerosol-generating device comprises an extractor defining a cavity having a first end with a circular shaped cross-section and a second end with an oval shaped cross-section;

Figure 7 shows a schematic illustration of the extractor of the aerosol-generating device of Figure 6;

Figure 8 shows a schematic illustration of the aerosol-generating device of Figure 6, in which the extractor is received on the housing of the aerosol-generating device, and the extractor is arranged in a second position wherein a heating element of the device does not extend into the cavity of the extractor;

Figure 9 shows a schematic illustration of an aerosol-generating system comprising the aerosol-generating device of Figure 6 and the aerosol-generating article of Figure 4, in which the extractor is received on the housing of the aerosol-generating device, and the extractor is arranged in a first position wherein the heating element of the device extends into the cavity of the extractor, and in which a portion of the aerosol-generating article is received in the cavity of the extractor;

Figure 10a shows a schematic illustration of a plan view of the extractor of the aerosolgenerating device of Figure 6 looking into the cavity of the extractor from an open first end of the cavity, Figure 10b shows a schematic illustration of a side view of the extractor of the aerosolgenerating device of Figure 6, and Figure 10c shows a schematic illustration of another side view of the extractor of the aerosol-generating device of Figure 6, rotated 90 degrees compared to Figure 10b; Figure 11 a shows a schematic illustration of a plan view of another embodiment of an extractor according to the disclosure that is suitable for use in the aerosol-generating device of Figure 6, looking into the cavity of the extractor from an open first end of the cavity, Figure 11 b shows a schematic illustration of a side view of the extractor of Figure 11 a, and Figure 11c shows a schematic illustration of another side view of the extractor of Figure 11a, rotated 90 degrees compared to Figure 11 b;

Figure 12a shows a schematic illustration of a plan view of another embodiment of an extractor according to the disclosure that is suitable for use in the aerosol-generating device of Figure 6, looking into the cavity of the extractor from an open first end of the cavity, Figure 12b shows a schematic illustration of a side view of the extractor of Figure 12a, and Figure 12c shows a schematic illustration of another side view of the extractor of Figure 12a, rotated 90 degrees compared to Figure 12b;

Figure 13a shows a schematic illustration of a plan view of another embodiment of an extractor according to the disclosure that is suitable for use in the aerosol-generating device of Figure 6, looking into the cavity of the extractor from an open first end of the cavity, Figure 13b shows a schematic illustration of a side view of the extractor of Figure 13a, and Figure 13c shows a schematic illustration of another side view of the extractor of Figure 13a, rotated 90 degrees compared to Figure 13b;

Figure 14a shows a schematic illustration of a plan view of another embodiment of an extractor according to the disclosure that is suitable for use in the aerosol-generating device of Figure 6, looking into the cavity of the extractor from an open first end of the cavity, Figure 14b shows a schematic illustration of a side view of the extractor of Figure 14a, and Figure 14c shows a schematic illustration of another side view of the extractor of Figure 14a, rotated 90 degrees compared to Figure 14b;

Figure 15a shows a schematic illustration of a plan view of another embodiment of an extractor according to the disclosure that is suitable for use in the aerosol-generating device of Figure 6, looking into the cavity of the extractor from an open first end of the cavity, Figure 15b shows a schematic illustration of a side view of the extractor of Figure 15a;

Figure 16a shows a schematic illustration of a plan view of another embodiment of an extractor according to the disclosure that is suitable for use in the aerosol-generating device of Figure 6, looking into the cavity of the extractor from an open first end of the cavity, Figure 16b shows a schematic illustration of a side view of the extractor of Figure 16a; and

Figure 17a shows a schematic illustration of a plan view of another embodiment of an extractor according to the disclosure that is suitable for use in the aerosol-generating device of Figure 6, looking into the cavity of the extractor from an open first end of the cavity, Figure 17b shows a schematic illustration of a side view of the extractor of Figure 17a.

Figure 1 and Figure 2 show an aerosol-generating device 10 according to an embodiment of the disclosure. The aerosol-generating device 10 comprises a cavity 20 for receiving an aerosolforming substrate. The aerosol-generating device 10 further comprises a housing 11 having a tubular portion 12 at one end, which defines the cavity 20.

The aerosol-generating device 10 further comprises a heating element 14, in the form of a blade, extending into the cavity 20, and an electrical power supply 15, in the form of a rechargeable lithium ion battery, and a controller 16 housed in the housing 11 , at the opposite end of the housing 11 to the tubular portion 12. The controller 16 is configured to control the supply of electrical power from the power supply 15 to the heating element 14 to heat an aerosol-forming substrate received in the cavity 20.

The cavity 20 comprises a first end, which is open for insertion of an aerosol-forming substrate into the cavity 20, and a second end, opposite the first end, which is substantially closed. A first end portion 21 of the cavity 20 extends from the first end of the cavity 20, and a second end portion 22 of the cavity 20 extends from the second end of the cavity 20. The first end portion 21 extends to and terminates at an intersection between the first end portion 21 and the second end portion 22, and the second end portion 22 extends to and terminates at the intersection between the first end portion 21 and the second end portion 22.

The cavity 20 has a length extending between the first end and the second end. The cavity 20 also has a cross-section perpendicular to the length. The shape of the cross-section of the cavity 20 at the second end is different to the shape of the cross-section of the cavity 20 at the first end. As shown in Figure 3, at the first end of the cavity 20 the cross-section of the cavity 20 is substantially circular, and at the second end of the cavity 20, the cross-section of the cavity 20 is substantially oval. The major diameter of the oval cross-section at the second end of the cavity 20 is substantially the same as the diameter of the circular cross-section at the first end of the cavity 20. In other words, the largest dimension of the oval cross-section at the second end of the cavity 20 is substantially the same as the diameter of the circular cross-section at the first end of the cavity 20. The minor diameter of the oval cross-section at the second end of the cavity 20 is less than the diameter of the circular cross-section at the first end of the cavity 20. The surface area of the cross-section of the cavity at the second end is less than the surface area of the cross-section of the cavity at the first end. However, the perimeter of the cross-section of the cavity 20 at the second end is substantially the same as the shape of the cross-section of the cavity 20 at the first end. Although in this embodiment the major diameter of the oval cross-section at the second end of the cavity 20 is the same as the diameter of the circular cross-section at the first end of the cavity 20, it will be appreciated that in other embodiments the major diameter of the oval cross-section at the second end of the cavity 20 is greater than the diameter of the circular cross-section at the first end of the cavity 20 in order to ensure that the perimeter of the oval cross-section at the second end of the cavity 20 is the same as the perimeter of the circular cross-section at the first end of the cavity 20.

The shape of the cross-section of the cavity 20 is substantially circular along the length of the first end portion 21 , and the shape of the cross-section of the cavity 20 is substantially oval along the length of the second end portion 22. However, the shape of the cross-section of the cavity 20 gradually changes from circular to oval at the intersection between the first end portion 21 and the second end portion 22.

The heating element 14 extends into the cavity 20 from the second end, and extends through the second end portion 22 to the intersection between the second end portion 22 and the first end portion 21 , but not into the first end portion 21 . The heating element 14 is elongate and thin, having a length and a width that are substantially greater than a thickness. The heating element 14 also has a pointed end, which enables the heating element to penetrate an aerosolforming substrate. As shown in Figures 1 , 2, and 3, the width of the heating element 14 extends substantially in the direction of the major axis of the oval cross-section of the second end of the cavity 20. In other words, the width of the heating element 14 extends substantially in the direction of the largest dimension of the oval cross-section of the second end of the cavity 20. In this orientation, the oval cross-section of the cavity 20 at the second end complements the shape of the heating element 14.

Figure 4 shows an aerosol-generating article 50 for use in the aerosol-generating device 10 of Figure 1 . The aerosol-generating article 50 comprises an aerosol-forming substrate 52, a hollow acetate tube 53, a polymeric filter 54, and a mouthpiece 55, arranged end-to-end and circumscribed by an outer wrapper 56. The aerosol-forming substrate 52 comprises a plug of tobacco and the mouthpiece 55 comprises a plug of cellulose acetate fibres. The aerosolgenerating article generally forms a cylindrical rod with a circular cross-section having substantially the same shape and dimensions as the first end of the cavity 20 of the aerosol-generating device 10 of Figure 1.

In use, the end of the aerosol-generating article 50 comprising the aerosol-forming substrate 52 is inserted into the cavity 20 at the first end. The aerosol-forming substrate 52 is not deformed when pushed through the first end portion 21 of the cavity, as the shape and dimensions of the cross-section of the aerosol-generating article 50 are substantially similar to the shape and dimensions of the cross-section of the first end portion 21 of the cavity 20. However, when the aerosol-generating article 50 is pushed into the second end portion 22 of the cavity 20, the aerosolforming substrate 52 is deformed by the tubular portion 12 of the housing 11 as the shape of the cross-section of the cavity 20 changes from circular to oval. The shape of the cross-section of the aerosol-forming substrate 52 changes when the aerosol-generating article 50 is pushed into the second end portion 22 of the cavity 20, and conforms to the shape and dimensions of the second end portion 22 of the cavity 20, becoming substantially oval. Also as the aerosol-generating article 50 is pushed into the second end portion 22 of the cavity 20, the pointed tip of the heating element 14 penetrates the aerosol-forming substrate 52, and the aerosol-forming substrate 52 is received over the heating element 14.

As shown in Figure 5, the length of the heating element 14 is substantially the same as the length of the aerosol-forming substrate 52.

When the shape of the cross-section of the aerosol-forming substrate 52 changes from circular to oval, the aerosol-forming substrate is compressed around the heating element. The oval shape of the cross-section more closely resembles the shape of the cross-section of the heating element 14, which, along with the compression, results in improved heat transfer from the heating element 14 to the aerosol-forming substrate 52, and improved distribution of heat through the aerosol-forming substrate 52, compared to if the shape of the cross-section of the aerosol-forming substrate 52 were to remain circular.

Figure 5 shows the aerosol-generating article 50 of Figure 4 inserted into the cavity 20 of the aerosol-generating device 10 of Figure 1. In use, a user activates the aerosol-generating device by pressing a button (not shown) on the housing 11 , and power is supplied to the heating element 14 from the power supply 15 to heat the aerosol-forming substrate 52. As a user draws on the mouthpiece 55 of the aerosol-generating article 50, air is drawn into the cavity 20 of the aerosol-generating device 10 through an inlet (not shown) in the tubular portion 12 of the housing of the housing 11 , and into the aerosol-generating article 50 through the aerosol-forming substrate 52. The heated aerosol-forming substrate 52 releases volatile compounds, which are drawn into the acetate tube 53, and which cool in the acetate tube 53 and polymeric filter 54 and condense to form an aerosol, which is inhaled by a user through the mouthpiece 55.

When the aerosol-generating article 50 is removed from the cavity 20 of the aerosolgenerating device 10, the aerosol-forming substrate 52 is no longer compressed. In some embodiments, the aerosol-forming substrate 52 may retain its deformed shape. However, in other embodiments the aerosol-forming substrate may return to its undeformed shape (i.e. with a substantially circular cross-section).

Figure 6 shows an aerosol-generating device 10 that is substantially similar to the aerosolgenerating device 10 of Figure 1 , and like reference numerals are used to denote like features. The aerosol-generating device 10 of Figure 6 is substantially the same as the aerosol-generating device 10 of Figure 1 , except that the aerosol-generating device 10 of Figure 6 comprises an extractor 30 for aiding removal of aerosol-forming substrate from the aerosol-generating device 10, and a cover 40.

The extractor 30 comprises a tubular body defining a cavity 20 for receiving aerosol-forming substrate. The cavity 20 has a substantially similar size and shape to the cavity 20 of the aerosolgenerating device 10 of Figure 1 . The cavity 20 comprises a first end, which is open for insertion of an aerosol-forming substrate into the cavity 20, and a second end, opposite the first end, which is substantially closed. A first end portion 21 of the cavity 20 extends from the first end of the cavity 20, and a second end portion 22 of the cavity 20 extends from the second end of the cavity 20. The first end portion 21 extends to and terminates at the second end portion 22, and the second end portion 22 extends to and terminates at the first end portion 21 .

The cavity 20 has a length extending between the first end and the second end, and a cross-section perpendicular to the length. As shown in Figure 7 and Figures 10, 10b and 10c, the shape of the cross-section of the cavity 20 at the second end is different to the shape of the crosssection of the cavity 20 at the first end. The cross-section of the first end of the cavity 20 is substantially circular. The cross-section of the second end of the cavity 20 is substantially oval. The surface area of the cross-section of the cavity 20 at the second end is less than the surface area of the cross-section of the cavity 20 at the first end. The perimeter of the cross-section of the cavity 20 at the second end is substantially the same as the shape of the cross-section of the cavity 20 at the first end.

The shape of the cross-section of the cavity 20 is substantially circular along the length of the first end portion 21 , and the shape of the cross-section of the cavity 20 is substantially oval along the length of the second end portion 22. The shape of the cross-section of the cavity 20 gradually changes at the intersection between the first end portion 21 and the second end portion 22.

The aerosol-generating device 10 further comprises a housing 11 including a tubular portion 12, which defines a cavity into which the extractor 30 is received. The aerosol-generating device 10 also comprises a heating element 14, in the form of a blade. As shown in Figures 8 and 9, the extractor 30 is received in the tubular portion 12 of the housing 11 , and is slidable relative to the tubular portion 12 and the heating element 14 between a first portion and a second position. In the first position, as shown in Figure 9, the heating element 14 extends into the cavity 20 of the extractor 30. In the second position, as shown in Figure 8, the heating element 14 does not extend into the cavity 20. The extractor 30 has an opening at the substantially closed second end of the cavity 20 to enable the heating element 14 to extend into the cavity 20 from the second end.

The aerosol-generating device 10 further comprises an electrical power supply 15, in the form of a rechargeable lithium ion battery, and a controller 16, which are both housed in the housing 11 , at the opposite end of the housing 11 to the tubular portion 12. The controller 16 is configured to control the supply of electrical power from the power supply 15 to the heating element 14 to heat an aerosol-forming substrate received in the cavity 20 of the extractor 30, when the extractor 30 is in the first position.

The cover 40 is removable receivable over the tubular portion 12, and substantially surrounds the tubular portion 12 in use, as shown in Figure 9, to further shield a user from the heat generated by the heating element 14.

Figure 9 shows the aerosol-generating article 50 of Figure 4 inserted into the cavity 20 of the extractor 30, and the extractor 30 arranged in the first position, with the heating element 14 extending into the cavity 20. Inserting the article 50 into the cavity 20 of the extractor 30 results in the same deformation of the article 50 and the aerosol-forming substrate 52 as described above with reference to Figure 5, changing the shape of the cross-section of the aerosol-forming substrate 52 from circular to oval.

In use, a user activates the aerosol-generating device by pressing a button (not shown) on the housing 11 , and power is supplied to the heating element 14 from the power supply 15 to heat the aerosol-forming substrate 52. As a user draws on the mouthpiece 55 of the aerosol-generating article 50, air is drawn into the cavity 20 of the aerosol-generating device 10 through an inlet (not shown) in the tubular portion 12 of the housing of the housing 11 , and into the aerosol-generating article 50 through the aerosol-forming substrate 52. The heated aerosol-forming substrate 52 releases volatile compounds, which are drawn into the acetate tube 53, and which cool in the acetate tube 53 and polymeric filter 54 and condense to form an aerosol, which is inhaled by a user through the mouthpiece 55.

After use, a user may extract the aerosol-generating article 50 from the aerosol-generating device 10 of Figure 6 by first moving the extractor 30 from the first position to the second position. This removes the aerosol-forming substrate 52 from the heating element 14 without causing any friction on the outer surfaces of the aerosol-generating article 50. A user may then remove the aerosol-generating article 50 from the extractor 30. This two-step process reduces the instantaneous friction forces experienced by the aerosol-generating article 50 as it is removed from the device 10 compared to removing the aerosol-generating article 50 from a device 10 without an extractor. As a result, the extractor 30 helps to reduce the likelihood of the aerosol-generating article 50 breaking during removal from the aerosol-generating device.

Figures 11 a, 11b and 11 c show an extractor 30 according to another embodiment of the disclosure. The extractor 30 of Figures 11a, 11 b and 11c is similar to the extractor 30 of Figures 6 to 10, and like reference numerals are used to denote like features.

The extractor 30 of Figures 11 a, 11b and 11c comprises a tubular body defining a cavity 20 for receiving aerosol-forming substrate. The cavity 20 comprises a first end, which is open for insertion of an aerosol-forming substrate into the cavity 20, and a second end, opposite the first end, which is substantially closed. A first end portion 21 of the cavity 20 extends from the first end of the cavity 20, and a second end portion 22 of the cavity 20 extends from the second end of the cavity 20. The extractor 30 has an opening at the substantially closed second end of the cavity 20 to enable a blade heating element 14 to extend into the cavity 20 from the second end.

The cavity 20 has a length extending between a first end and a second end, and a crosssection perpendicular to the length. The shape of the cross-section of the cavity 20 at the second end is different to the shape of the cross-section of the cavity 20 at the first end. The cross-section of the first end of the cavity 20 is substantially circular. The cross-section of the second end of the cavity 20 is substantially oval.

The difference between the extractor of Figures 11 a, 11b and 11c and the extractor of Figures 6 to 10 is that the major diameter of the oval cross-section at the second end of the cavity 20 of the extractor of Figures 11 a, 11 b and 11 c is less than the diameter of the circular crosssection at the first end of the cavity 20. In other words, the largest dimension of the oval crosssection at the second end of the cavity 20 is less than the diameter of the circular cross-section at the first end of the cavity 20. Reducing the length of the major diameter of the oval cross-section at the second end of the cavity 20 provides further compression of the aerosol-forming substrate 52 around the heating element 14, which may provide improved heat transfer from the heating element 14 to the aerosol-forming substrate 52.

In this embodiment, the perimeter of the cross-section of the cavity 20 at the second end is smaller than the perimeter of the cavity at the first end. As a result, when the aerosol-generating article 50 is inserted into the cavity 20 and moved to the second end, the outer wrapper 56 may crimp or wrinkle, as the aerosol-forming substrate 52 is compressed into the second end of the cavity 20. To reduce crimping or wrinkling of the outer wrapper 56, slits or cuts may be provided in the portion of the outer wrapper circumscribing the aerosol-forming substrate 52. The slits or cuts preferably extend in the direction of the length of the aerosol-generating article 50. Advantageously, the slits or cuts in the outer wrapper 56 may allow portions of the outer wrapper 56 to overlap without the outer wrapper 56 crimping or wrinkling when the aerosol-forming substrate is moved to the second end of the cavity 20.

Figures 12a, 12b and 12c show an extractor 30 according to another embodiment of the disclosure. The extractor 30 of Figures 12a, 12b and 12c is similar to the extractor 30 of Figures 6 to 10, and like reference numerals are used to denote like features.

The extractor 30 of Figures 12a, 12b and 12c comprises a tubular body defining a cavity 20 for receiving aerosol-forming substrate. The cavity 20 comprises a first end, which is open for insertion of an aerosol-forming substrate into the cavity 20, and a second end, opposite the first end, which is substantially closed. A first end portion 21 of the cavity 20 extends from the first end of the cavity 20, and a second end portion 22 of the cavity 20 extends from the second end of the cavity 20.

The cavity 20 has a length extending between a first end and a second end, and a crosssection perpendicular to the length. The shape of the cross-section of the cavity 20 at the second end is different to the shape of the cross-section of the cavity 20 at the first end. The cross-section of the first end of the cavity 20 is substantially circular. The cross-section of the second end of the cavity 20 is substantially oval. The major diameter of the oval cross-section at the second end of the cavity 20 of the extractor of Figures 12a, 12b and 12c substantially the same as the diameter of the circular cross-section at the first end of the cavity 20.

The difference between the extractor of Figures 12a, 12b and 12c and the extractor of Figures 6 to 10 is that the extractor 30 of Figures 12a, 12b and 12c has two openings at the substantially closed second end of the cavity 20 to enable two pin heating elements 14 to extend into the cavity 20 from the second end. The openings are arranged such that the pin heating elements extend into the cavity 20 at the foci of the oval shape of the cross-section at the second end of the cavity 20.

Figures 13a, 13b and 13c show an extractor 30 according to another embodiment of the disclosure. The extractor 30 of Figures 13a, 13b and 13c is similar to the extractor 30 of Figures 12a, 12b and 12c, and like reference numerals are used to denote like features.

The extractor 30 of Figures 13a, 13b and 13c comprises a tubular body defining a cavity 20 for receiving aerosol-forming substrate. The cavity 20 comprises a first end, which is open for insertion of an aerosol-forming substrate into the cavity 20, and a second end, opposite the first end, which is substantially closed. A first end portion 21 of the cavity 20 extends from the first end of the cavity 20, and a second end portion 22 of the cavity 20 extends from the second end of the cavity 20. The extractor 30 has two openings at the substantially closed second end of the cavity 20 to enable two pin heating elements 14 to extend into the cavity 20 from the second end.

The difference between the extractor of Figures 13a, 13b and 13c and the extractor of Figures 12a, 12b and 12c is that the major diameter of the oval cross-section at the second end of the cavity 20 of the extractor of Figures 13a, 13b and 13c is less than the diameter of the circular cross-section at the first end of the cavity 20.

Figures 14a, 14b and 14c show an extractor 30 according to another embodiment of the disclosure. The extractor 30 of Figures 14a, 14b and 14c is similar to the extractor 30 of Figures 12a, 12b and 12c, and like reference numerals are used to denote like features.

The extractor 30 of Figures 14a, 14b and 14c comprises a tubular body defining a cavity 20 for receiving aerosol-forming substrate. The cavity 20 comprises a first end, which is open for insertion of an aerosol-forming substrate into the cavity 20, and a second end, opposite the first end, which is substantially closed. A first end portion 21 of the cavity 20 extends from the first end of the cavity 20, and a second end portion 22 of the cavity 20 extends from the second end of the cavity 20. The extractor 30 has two openings at the substantially closed second end of the cavity 20 to enable two pin heating elements 14 to extend into the cavity 20 from the second end.

The cavity 20 has a length extending between a first end and a second end, and a crosssection perpendicular to the length. The shape of the cross-section of the cavity 20 at the second end is different to the shape of the cross-section of the cavity 20 at the first end.

The cross-section of the first end of the cavity 20 is substantially circular. The difference between the extractor of Figures 14a, 14b and 14c and the extractor of Figures 12a, 12b and 12c is that the cross-section of the second end of the cavity 20 of Figures 14a, 14b and 14c comprises two overlapping congruent circles, which form a two lobed shape similar to a figure of eight. The perimeter of the two lobed shape of the cross-section at the second end of the cavity 20 is substantially the same as the perimeter of the circular cross-section at the first end of the cavity 20.

Each pin heating element 14 extends into the second end of the cavity 20 through the centre of one of the two congruent circles. The two lobed shape of the cross-section at the second end of the cavity 20 positions a greater proportion of the aerosol-forming substrate received in the cavity 20 closer to the pin heating elements 14 than the circular cross-section of the first portion of the cavity 20, which may provide improved heat transfer from the pin heating elements 14 to the aerosol-forming substrate 52.

Figures 15a and 15b show an extractor 30 according to another embodiment of the disclosure. The extractor 30 of Figures 15a and 15b is similar to the extractor 30 of Figures 6 to 10, and like reference numerals are used to denote like features.

The extractor 30 of Figures 15a and 15b comprises a tubular body defining a cavity 20 for receiving aerosol-forming substrate. The cavity 20 comprises a first end, which is open for insertion of an aerosol-forming substrate into the cavity 20, and a second end, opposite the first end, which is substantially closed. A first end portion 21 of the cavity 20 extends from the first end of the cavity 20, and a second end portion 22 of the cavity 20 extends from the second end of the cavity 20. The extractor 30 has a single opening at the substantially closed second end of the cavity 20 to enable a single pin heating element 14 to extend into the cavity 20 from the second end.

The cavity 20 has a length extending between a first end and a second end, and a crosssection perpendicular to the length. The shape of the cross-section of the cavity 20 at the second end is different to the shape of the cross-section of the cavity 20 at the first end. The cross-section of the first end of the cavity 20 is substantially circular. The cross-section of the second end of the cavity 20 is substantially triangular.

The triangular cross-section at the second end of the cavity 20 is truncated at the corners such that the triangular cross-section of the second end of the cavity 20 does not extend beyond the circular cross-section of the first end of the cavity. The triangular cross-section at the second end of the cavity 20 positions a greater proportion of the aerosol-forming substrate received in the cavity 20 closer to the pin heating element 14 than the circular cross-section of the first portion of the cavity 20, which may provide improved heat transfer from the heating element 14 to the aerosol-forming substrate 52.

Figures 16a and 16b show an extractor 30 according to another embodiment of the disclosure. The extractor 30 of Figures 16a and 16b is similar to the extractor 30 of Figures 15a and 15b, and like reference numerals are used to denote like features.

The extractor 30 of Figures 16a and 16b comprises a tubular body defining a cavity 20 for receiving aerosol-forming substrate. The cavity 20 comprises a first end, which is open for insertion of an aerosol-forming substrate into the cavity 20, and a second end, opposite the first end, which is substantially closed. A first end portion 21 of the cavity 20 extends from the first end of the cavity 20, and a second end portion 22 of the cavity 20 extends from the second end of the cavity 20. The extractor 30 has a single opening at the substantially closed second end of the cavity 20 to enable a single pin heating element 14 to extend into the cavity 20 from the second end. The cavity 20 has a length extending between a first end and a second end, and a crosssection perpendicular to the length. The shape of the cross-section of the cavity 20 at the second end is different to the shape of the cross-section of the cavity 20 at the first end. The cross-section of the first end of the cavity 20 is substantially circular. The shape of the cross-section of the cavity 20 at the second end is substantially triangular.

The difference between the extractor 30 of Figures 16a and 16b and the extractor 30 of Figures 15a and 15b is that the lengths of the sides of the triangular cross-section of the second end of the cavity 20 of the extractor 30 of Figures 16a and 16b are less than the lengths of the sides of the triangular cross-section of the second end of the cavity 20 of the extractor 30 of Figures 15a and 15b. This reduces the surface area of the triangular the cross-section of the second end of the cavity 20 of the extractor 30 of Figures 16a and 16b compared to the surface area of the triangular cross-section of the second end of the cavity 20 of the extractor 30 of Figures 15a and 15b, which may provide improved heat transfer from the heating element 14 to the aerosol-forming substrate 52.

Figures 17a and 17b show an extractor 30 according to another embodiment of the disclosure. The extractor 30 of Figures 17a and 17b is similar to the extractor 30 of Figures 6 to 10, and like reference numerals are used to denote like features.

The extractor 30 of Figures 17a and 17b comprises a tubular body defining a cavity 20 for receiving aerosol-forming substrate. The cavity 20 comprises a first end, which is open for insertion of an aerosol-forming substrate into the cavity 20, and a second end, opposite the first end, which is substantially closed. A first end portion 21 of the cavity 20 extends from the first end of the cavity 20, and a second end portion 22 of the cavity 20 extends from the second end of the cavity 20. The extractor 30 has a single opening at the substantially closed second end of the cavity 20 to enable a single pin heating element 14 to extend into the cavity 20 from the second end.

The cavity 20 has a length extending between a first end and a second end, and a crosssection perpendicular to the length. The shape of the cross-section of the cavity 20 at the second end is the same as the shape of the cross-section of the cavity 20 at the first end. The crosssection of the first end of the cavity 20 is substantially circular, and the cross-section of the second end of the cavity 20 is substantially circular.

The diameter of the circular cross-section of the cavity 20 at the second end of the cavity 20 is less than the diameter of the circular cross-section at the first end of the cavity 20. This reduces the surface area of the cross-section of the second end of the cavity 20 compared to the surface area of the cross-section of the first end of the cavity 20, which may provide improved heat transfer from the pin heating element 14 to the aerosol-forming substrate 52.

Claims

-45- CLAIMS

1 . An aerosol-generating device comprising a cavity for receiving an aerosol-forming substrate, wherein the cavity has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length, and wherein at least one of: the shape of the cross-section of the cavity varies along the length of the cavity; the surface area of the cross-section of the cavity varies along the length of the cavity; and a dimension of the cross-section of the cavity varies along the length of the cavity.

2. An aerosol-generating device according to claim 1 , wherein the dimension of the crosssection at the first end of the cavity is greater than the dimension of the cross-section at the second end of the cavity.

3. An aerosol-generating device according to claim 1 or claim 2, wherein the surface area of the cross-section of the cavity at the first end of the cavity is greater than the surface area of the cross-section of the cavity at the second end of the cavity.

4. An aerosol-generating device according to any one of claims 1 to 3, wherein the perimeter of the cross-section of the cavity remains substantially constant along the length of the cavity.

5. An aerosol-generating device according to any one of claims 1 to 4, wherein the shape of the cross-section at the first end is substantially circular, and the shape of the cross-section at the second end is one of: substantially triangular; substantially oval or elliptical; and substantially square or rectangular.

6. An aerosol-generating device according to any one of claims 1 to 4, wherein the shape of the cross-section of the cavity at the first end is substantially circular, and the shape of the crosssection of the cavity at the second end is substantially triangular, and wherein the aerosolgenerating device comprises a pin heating element that extends into the cavity at the second end. -46-

7. An aerosol-generating device according to any one of claims 1 to 4, wherein the shape of the cross-section of the cavity at the first end is substantially circular, and the shape of the crosssection of the cavity at the second end is substantially oval or elliptical, and wherein the aerosolgenerating device comprises a blade heating element that extends into the cavity at the second end or two pin heating elements that extend into the cavity at the second end.

8. An aerosol-generating device according to any one of claims 1 to 7, wherein the aerosolgenerating device further comprises an extractor for extracting an aerosol-forming substrate from the aerosol-generating device, wherein the extractor comprises a body defining the cavity for receiving the aerosol-forming substrate.

9. An extractor for extracting an aerosol-forming substrate from an aerosol-generating device, wherein the extractor comprises a body defining a cavity for receiving the aerosol-forming substrate, and wherein the cavity has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length, and wherein at least one of: the shape of the cross-section of the cavity varies along the length of the cavity; the surface area of the cross-section of the cavity varies along the length of the cavity; and a dimension of the cross-section of the cavity varies along the length of the cavity.

10. An extractor according to claim 9, wherein the dimension of the cross-section at the first end of the cavity is greater than the dimension of the cross-section at the second end of the cavity.

11. An extractor according to claims 9 or 10, wherein the surface area of the cross-section of the cavity at the first end of the cavity is greater than the surface area of the cross-section of the cavity at the second end of the cavity.

12. An extractor according to any one of claims 9 to 11 , wherein the perimeter of the crosssection of the cavity remains substantially constant along the length of the cavity. -47-

13. An extractor according to any one of claims 9 to 12, wherein the shape of the cross-section at the first end is substantially circular, and the shape of the cross-section at the second end is one of: substantially triangular; substantially oval or elliptical; and substantially square or rectangular.

14. An aerosol-generating system comprising: an aerosol-forming substrate; and an aerosol-generating device according to any one of claims 1 to 8.

15. An aerosol-generating system according to claim 14, wherein the aerosol-forming substrate has: a first end and an opposing second end; a length between the first end and the second end; and a cross-section perpendicular to the length, and wherein before the aerosol-forming substrate is received in the cavity of the aerosol-generating device: the shape of the cross-section of the aerosol-forming substrate is substantially constant along the length of the aerosol-forming substrate, and is substantially similar to the shape of the cross-section of the cavity at the first end of the cavity; and a dimension of the cross-section of the aerosol-forming substrate is substantially constant along the length of the aerosol-forming substrate, and is substantially similar to the shape of the cross-section of the cavity at the first end of the cavity.