FIELD

The present invention relates to an aerosol provision device, an aerosol generating system and a method of generating an aerosol.

BACKGROUND

Electronic aerosol generating systems such as electronic cigarettes (e-cigarettes) generally contain a reservoir of a source liquid containing a formulation, typically including nicotine, from which an aerosol is generated e.g. through heat vaporisation. An aerosol source for an aerosol provision system may thus comprise a heater having a heating element arranged to receive source liquid from the reservoir, for example through wicking or capillary action. While a user inhales on the device, electrical power is supplied to the heating element to vaporise source liquid in the vicinity of the heating element to generate an aerosol for inhalation by the user. Such devices are usually provided with one or more air inlet holes located away from a mouthpiece end of the system. When a user sucks on a mouthpiece connected to the mouthpiece end of the system, air is drawn in through the inlet holes and past the aerosol source. There is a flow path connecting between the aerosol source and an opening in the mouthpiece so that air drawn past the aerosol source continues along the flow path to the mouthpiece opening, carrying some of the aerosol from the aerosol source with it. The aerosolcarrying air exits the aerosol provision system through the mouthpiece opening for inhalation by the user.

Other aerosol provision devices generate aerosol from a solid material, such as tobacco or a tobacco derivative. Such devices operate in a broadly similar manner to the liquid-based systems described above, in that the solid tobacco material is heated to a vaporisation temperature to generate an aerosol which is subsequently inhaled by a user.

In most aerosol provision devices, users seek consistent delivery on a puff-by- puff basis such that each puff tastes the same and/or provides the same desired effect. However, the devices described above are not always capable of providing consistent delivery.

It is desired to provide an aerosol provision device which delivers an improved delivery of aerosol and/or which provides a user with an improved sensorial experience. SUMMARY

According to an aspect there is provided an aerosol provision device for generating aerosol from aerosol generating material, the aerosol provision device comprising: at least one chamber having a warming element comprising ferritic material; a reception region arranged to receive a planar aerosol generating article comprising aerosol generating material; and at least one aerosol generator arranged to cause aerosol to be generated from the aerosol generating material; wherein the reception region is located between the at least one aerosol generator and the at least one warming element.

According to various embodiments a warming element is provided in order to prevent or at least substantially reduce the likelihood of aerosol generated from a planar aerosol generating article condensing within a heating chamber. The aerosol generating article may comprise a susceptor. Optionally, the susceptor comprises aluminium. Other embodiments are contemplated wherein the susceptor comprises an aluminium alloy. Optionally, the warming element and the susceptor may be spaced < 4 mm apart in use. The warming element may comprise a plate or surface of ferritic material which may be heated to a temperature of e.g. 60-150 °C during a session of use. The warming element may be warmed by receiving a time varying magnetic field generated by one or more induction coils which may comprise the aerosol generator or heater. In alternative embodiments the warming element may be heated by a warming unit which may comprise either one or more resistive heaters and/or one or more inductive heaters which are separate from and distinct to the aerosol generator or heater. The warming element 200 may comprise a thin plate, coating or foil which may have a thickness < 25 pm. It is not essential that the aerosol generating article comprises a planar aerosol generating article and embodiments are contemplated wherein the reception region is arranged to receive a non-planar aerosol generating article. For example, the aerosol generating article may comprise a curved, corrugated or cylindrical substrate. Embodiments are contemplated wherein the aerosol generating article is cylindrical or has a circular or polygonal cross-sectional area.

According to various embodiments an aerosol provision device is provided comprising a warming element which helps to reduce or substantially prevent condensate forming on the walls of a reception region and/or elsewhere within the aerosol provision device.

According to various embodiments there is provided an aerosol provision device for generating aerosol from aerosol generating material, the aerosol provision device comprising at least one chamber having a warming element. The warming element may comprise ferritic material. The aerosol provision device may comprise a reception region arranged to receive an aerosol generating article comprising aerosol generating material. The aerosol generating article may comprise a planar aerosol generating article. The aerosol provision device may further comprise at least one aerosol generator arranged to cause aerosol to be generated from the aerosol generating material. The reception region may be located between the at least one aerosol generator and the at least one warming element.

Optionally, the aerosol generator comprises one or more first inductors.

Optionally, at least one of the one or more first inductors comprise a substantially planar inductor coil.

Optionally, the one or more first inductors are also arranged to warm the warming element in order to reduce the formation of condensation within the chamber.

Optionally, the aerosol generator comprises one or more first resistive heaters.

Optionally, the aerosol generator is arranged to warm the warming element to a temperature in the range 60-150 °C during a session of use. According to an embodiment the aerosol generator may be arranged to warm the warming element to a temperature in the range 60-70 °C, 70-80 °C, 80-90 °C, 90-100 °C, 100-110 °C, 110-120 °C, 120-130 °C, 130-140 °C or 140-150 °C.

Optionally, the aerosol provision device further comprises a warming unit arranged to warm the warming element in order to reduce the formation of condensation within the chamber.

Optionally, the warming unit comprises one or more second inductors.

Optionally, the warming unit comprises one or more second resistive heaters.

Optionally, the ferritic material comprises a coating or foil.

Optionally, the ferritic material has a thickness < 25 pm. According to various embodiments the ferritic material may have a thickness < 5 pm, 5-10 pm, 10-15 pm, 15- 20 pm or 20-25 pm.

Optionally, the ferritic material may have a relative magnetic permeability selected from the range: (i) 100-200 p/po; (ii) 200-300 p/po; (iii) 300-400 p/po; (iv) 400-500 p/po; (v) 500-600 p/po; (vi) 600-700 p/po; (vii) 700-800 p/po; (viii) 800-900 p/po; (ix) 900- 1000 p/p ₀ ; (x) 1000-1100 p/p ₀ ; (xi) 1100-1200 p/p ₀ ; (xii) 1200-1300 p/p ₀ ; (xiii) 1300-1400 p/|Jo; (Xiv) 1400-1500 p/po; (XV) 1500-1600 p/p ₀ ; (xvi) 1600-1700 p/p ₀ ; (xvii) 1700-1800 p/po; (xviii) 1800-1900 p/po; (xix) 1900-2000 p/po; (xx) > 2000 p/po.

Optionally, the warming element is planar. Alternatively, the warming element may be curved, concave, convex or dome shaped.

Optionally, the aerosol provision device comprises a plurality of aerosol generators, wherein at least some or each aerosol generator is arranged to cause aerosol to be generated from a different portion of the planar aerosol generating article.

Optionally, the aerosol provision device comprises a plurality of chambers, wherein at least some or each chamber is arranged to receive aerosol generated from a different portion of the planar aerosol generating article.

Optionally, at least some or each chamber comprises a warming element comprising ferritic material.

Optionally, the aerosol provision device is arranged to move, translate or rotate the planar aerosol generating article relative to the at least one aerosol generator during a session of use.

According to another aspect there is provided an aerosol generating system comprising: an aerosol provision device as described above; and a planar aerosol generating article comprising aerosol generating material and a susceptor.

Optionally, the susceptor comprises a metallic foil. Other embodiments are contemplated wherein the susceptor comprises a metallic coating on a substrate.

Optionally, the susceptor comprises aluminium. Other embodiments are contemplated wherein the susceptor comprises an aluminium alloy.

In particular, the susceptor may comprise aluminium foil or an aluminium coating on a substrate. The substrate may provide a degree of rigidity to the planar aerosol generating article.

Optionally, the susceptor either has a relative magnetic permeability 1.0 p/po or the susceptor has a relative magnetic permeability selected from the group consisting of: (i) < 100 p/po; (ii) 100-200 p/po; (iii) 200-300 p/po; (iv) 300-400 p/po; (v) 400-500 p/po; (vi) 500-600 p/po; (vii) 600-700 p/po; (viii) 700-800 p/po; (ix) 800-900 p/po; (x) 900-1000 p/po; (xi) 1000-1100 p/p ₀ ; (xii) 1100-1200 p/p ₀ ; (xiii) 1200-1300 p/p ₀ ; (xiv) 1300-1400 p/p ₀ ; (xv) 1400-1500 p/po; (xvi) 1500-1600 p/po; (xvii) 1600-1700 p/po; (xviii) 1700-1800 p/po; (xix) 1800-1900 p/po; (xx) 1900-2000 p/po; and (xxi) > 2000 p/po.

Optionally, the susceptor has a thickness < 10 pm. According to various embodiments the susceptor may have a thickness < 1 pm, 1-2 pm, 2-3 pm, 3-4 pm, 4-5 pm, 5-6 pm, 6-7 pm, 7-8 pm, 8-9 pm or 9-10 pm. Other embodiments are contemplated wherein the susceptor may comprise a plurality of layers and may have a total thickness > 10 pm.

Optionally, the warming element and the susceptor may be spaced < 4 mm apart. For example, according to various embodiments the spacing between the warming element and the susceptor may be < 1 mm, 1-2 mm, 2-3 mm or 3-4 mm.

Optionally, the aerosol generator is arranged to heat the susceptor and/or the aerosol generating material to a temperature in the range 200-400 °C during a session of use. According to various embodiments the aerosol generator is arranged to heat the susceptor to a temperature in the range 200-220 °C, 220-240 °C, 240-260 °C, 260-280 °C, 280-300 °C, 300-320 °C, 320-340 °C, 340-360 °C, 360-380 °C or 380-400 °C during a session of use. According to various embodiments the aerosol generator is arranged to heat the aerosol generating material to a temperature in the range 200-220 °C, 220- 240 °C, 240-260 °C, 260-280 °C, 280-300 °C, 300-320 °C, 320-340 °C, 340-360 °C, 360- 380 °C or 380-400 °C during a session of use.

Optionally, the ferritic material has a magnetic permeability pi and the susceptor has a magnetic permeability p2 and wherein the ratio pi/p2 is < 100, 100-500, 500-1000, 1000-1500, 1500-2000, 2000-2500, 2500-3000, 3000-3500, 3500-4000, 4000-4500, 4500-5000 or > 5000.

Optionally, the aerosol generator comprises one or more induction coils having a first surface area Ai in a plane parallel with a planar surface of the susceptor and wherein the warming element has a second surface area A2 in a plane parallel with the planar surface of the susceptor, wherein the ratio A2/A1 is in the range: (i) 0.7-0.8; (ii) 0.8- 0.9; (iii) 0.9-1.0; (iv) 1.0-1.1 ; (v) 1.1-1.2; and (vi) 1.2-1.3.

According to another aspect there is provided a method of generating aerosol comprising: providing an aerosol provision device as described above; and introducing a planar aerosol generating article comprising aerosol generating material and a susceptor into the aerosol provision device.

Other embodiments are contemplated wherein the aerosol generating article may not necessarily comprise a planar aerosol generating article. For example, embodiments are contemplated wherein the aerosol generating article may comprise a curved, corrugated or non-planar substrate.

According to another aspect there is provided an aerosol provision device for generating aerosol from aerosol generating material, the aerosol provision device comprising: at least one chamber having a warming element comprising ferritic material; a reception region arranged to receive an aerosol generating article comprising aerosol generating material; and at least one aerosol generator arranged to cause aerosol to be generated from the aerosol generating material.

Optionally, the reception region is located between the at least one aerosol generator and the at least one warming element.

Optionally, the reception region is arranged to receive a planar aerosol generating article comprising aerosol generating material.

According to another aspect there is provided an aerosol generating system comprising: an aerosol provision device as described above; and an aerosol generating article comprising aerosol generating material and a susceptor.

According to another aspect there is provided a method of generating aerosol comprising: providing an aerosol provision device as described above; and introducing an aerosol generating article comprising aerosol generating material and a susceptor into the aerosol provision device.

The method may further comprise activating the aerosol provision device.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic sectional view of a portion of an aerosol provision device;

Fig. 2 is a schematic sectional view of a portion of an aerosol provision device according to an embodiment;

Fig. 3 is a schematic sectional view of a portion of an aerosol provision device according to an embodiment; Fig. 4 is a schematic top-down view of a rounded substrate comprising portions of aerosol generating material;

Fig. 5 is a schematic top-down view of a portion of an aerosol provision device and shows a substrate having portions of aerosol generating material provided thereon received in a reception region of the aerosol provision device and an aerosol generator or heater comprising heating elements which may be arranged below the substrate;

Fig. 6 is a schematic top-down view of a portion of an aerosol generating article according to an embodiment;

Fig. 7A is an example of a cross-section of a schematic representation of an aerosol provision system comprising an aerosol provision device according to an embodiment in combination with a planar aerosol generating article, wherein the aerosol provision device comprises a plurality of substantially planar inductor coils and the planar aerosol generating article comprises a plurality of portions of aerosol generating material and corresponding susceptor portions, Fig. 7B shows a plan view of the planar aerosol generating article, Fig. 7C shows an end-on view of the planar aerosol generating article, Fig. 7D shows a side-on view of the planar aerosol generating article and Fig. 7E shows a cross-sectional, top-down view of the heating elements of an aerosol provision device according to an embodiment;

Fig. 8A shows an example of a substantially planar inductor coil having a trapezoid shape and Fig. 8B shows another example of a substantially planar multi layered inductor coil having an overall trapezoid shape;

Fig. 9 shows an aerosol provision device according to an embodiment wherein the aerosol provision device comprises a chamber and wherein a planar aerosol generating article is located in a reception region of the aerosol provision device and wherein a warming element is located adjacent to the reception region and is arranged to reduce the formation of condensation within the chamber;

Fig. 10 shows an image of a disc shaped planar aerosol generating article and a portion of an aerosol provision device having a chamber with an integral warming element provided therein according to an embodiment; and

Fig. 11 shows experimental results illustrating the temperature as a function of time of an aluminium susceptor (upper trace) and a stainless steel warming element (lower trace) which were both heated by a time varying magnetic field generated by an inductor coil according to an embodiment. DETAILED DESCRIPTION

While the invention is susceptible to various modifications and alternative forms, specific embodiments are shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the drawings and detailed description of the specific embodiments are not intended to limit the invention to the particular forms disclosed. On the contrary, the invention covers all modifications, equivalents and alternatives falling within the scope of the present invention as defined by the appended claims.

Aspects and features of certain examples and embodiments are discussed I described herein. Some aspects and features of certain examples and embodiments may be implemented conventionally and these are not discussed I described in detail in the interests of brevity. It will thus be appreciated that aspects and features of apparatus and methods discussed herein which are not described in detail may be implemented in accordance with any conventional techniques for implementing such aspects and features.

The present disclosure relates to aerosol provision systems, which may also be referred to as aerosol provision systems, such as e-cigarettes. Throughout the following description the term “e-cigarette” or “electronic cigarette” may sometimes be used, but it will be appreciated this term may be used interchangeably with aerosol provision system I device and electronic aerosol provision system I device. Furthermore, and as is common in the technical field, the terms "aerosol" and "vapour", and related terms such as "vaporise", "volatilise" and "aerosolise", may generally be used interchangeably.

Fig. 1 illustrates a schematic view of a portion of an aerosol provision device 100. The aerosol provision device 100 has an aerosol generating article 101 arranged within a chamber 190 of the aerosol provision device 100. The aerosol provision device 100 includes a reception region 225 which is arranged to receive the aerosol generating article 101. The aerosol generating article 101 comprises aerosol generating material 114 which may be provided on a substrate 110.

According to various embodiments the aerosol generating material 114 may be present on or in a support, to form a substrate 110. The support (or substrate 110) may, for example, be or comprise paper, card, paperboard, cardboard, reconstituted material, a plastics material, a ceramic material, a composite material, glass, a metal or a metal alloy. In some embodiments, the support comprises a susceptor. In some embodiments, the susceptor is embedded within the aerosol generating material 114. In some alternative embodiments, the susceptor is on one or either side of the aerosol generating material 114. According to various embodiments a susceptor 112 may be provided upon the substrate 110. The susceptor 112 may comprise aluminium foil. However, other embodiments are contemplated wherein no susceptor is provided upon the substrate 110. Yet further embodiments are contemplated wherein a susceptor made from a material other than aluminium is provided upon the substrate 110. According to various embodiments the substrate 110 may comprise paper or card. Aerosol generating material 114 may be arranged upon the susceptor 112 which may comprise aluminium foil. The combination of the aerosol provision device 100 and the aerosol generating article 101 form an aerosol provision system.

The aerosol generating material 114 may be arranged as a plurality of doses or portions on the susceptor 112 or more generally upon the substrate 110. The lower surface of the substrate 110 may be smooth or rough. The upper surface of the susceptor 112 (if provided) and/or the aerosol generating material 114 and/or the substrate 110 may be smooth or rough.

The aerosol provision device 100 has an aerosol generator or heater 120 for heating the aerosol generating material 114 and optionally also for heating a susceptor 112 which may be arranged on the substrate 110. The aerosol generator or heater 120 is an element of the aerosol provision device 100 which transfers energy from a power source, such as a battery (not shown), to the aerosol generating material 114 in order to generate aerosol from the aerosol generating material 114. The aerosol generator or heater 120 may comprise one or more inductor coils which may be arranged to generate a time varying magnetic field which interacts with the susceptor 112 causing the susceptor 112 to become hot and to generate aerosol from aerosol generating material 114 which is in contact with the portion of the susceptor 112 which is heated.

The aerosol provision device 100 may comprise a movement mechanism 130 arranged to move the substrate 110 and in particular portions (or, in some cases, doses) of aerosol generating material 114. The portions of aerosol generating material 114 may be rotationally movable relative to the aerosol generator or heater 120 such that portions of the aerosol generating material 114 are presented, in this case individually, to the aerosol generator or heater 120. The aerosol provision device 100 is arranged such that at least one dose of the aerosol generating material 114 is rotated around an axis A at an angle 0 to the rear surface 116 of the substrate 110. The substrate 110 in this implementation comprises a substantially flat or planar substrate 110 and may be formed either partially or entirely of paper or card.

The substrate 110 shown in Fig. 1 has five doses (or portions) of aerosol generating material 114 provided on a susceptor 112 which may comprise aluminium foil. However, according to other embodiment the substrate 110 may have greater or fewer doses of aerosol generating material 114. According to various embodiments the substrate 110 may have the doses of aerosol generating material 114 arranged in discrete doses as shown in Fig. 1. In other examples, the doses may be in the form of a disc, which may be continuous or discontinuous in the circumferential direction of the substrate 110. In still other examples, the doses may be in the form of an annulus, a ring or any other shape. The substrate 110 may or may not have a rotationally symmetrical distribution of doses at the upper surface of the substrate 110 about the axis A. A symmetrical distribution of doses would enable equivalently positioned doses (within the rotationally symmetrical distribution) to receive an equivalent heating profile from the aerosol generator or heater 120 upon rotation about the axis A, if desired.

According to various embodiments the substrate 110 may have a layered structure and may be fabricated from a plurality of materials. In one example, the substrate 110 may have a layer formed from at least one of a thermally conductive material, an inductive material, a permeable material or an impermeable material.

The susceptor layer 112 may comprise a metallic element that is arranged to be heated by a time varying magnetic field. In such implementations, the aerosol generator or heater 120 may include an induction coil, which, when energised, causes heating within the metallic element which is provided on the substrate 110. The degree of heating may be affected by the distance between the metallic element and the induction coil.

Embodiments are also contemplated wherein the aerosol generating article 101 comprises a metallic element (which acts as a susceptor) upon which aerosol generating material 114 is provided and wherein the combination of the metallic element and the aerosol generating material 114 is sufficiently rigid such that no substrate 110 (e.g. paper or card) is provided.

The aerosol forming material 114 may be disposed on the susceptor layer 112 such that the distance from the aerosol generator or heater 120 to the aerosol forming material 114 is within the range of from 0.010 mm, 0.015 mm, 0.017 mm, 0.020 mm, 0.023 mm, 0.025 mm, 0.05 mm, 0.075 mm, 0.1 mm, to about 4 mm, 3.5 mm, 3 mm, 2.5 mm, 2.0 mm, 1.5 mm, 1.0 mm, 0.5 mm or 0.3 mm. In some cases, there may be a minimum spacing between the aerosol generator or heater 120 and the aerosol forming material 114 provided on the substrate 110 of at least about 10 pm, 15 pm, 17 pm, 20 pm, 23 pm, 25 pm, 50 pm, 75 pm or 0.1 mm.

The aerosol provision device 100 may have a plurality of chambers or regions that may or may not be separate from one another which are arranged to receive aerosol generated from the aerosol generating material 114. The aerosol provision device 100 may have a power chamber (not shown) comprising a power source for supplying power to aerosol generator or heater 120 and/or the movement mechanism 130. The aerosol generator or heater 120 may comprise either an inductive or an electrically resistive heater. However, in other examples, the aerosol generator or heater 120 may comprise a chemically activated heater which may or may not operate via exothermic reactions or the like.

According to an embodiment the aerosol generator or heater 120 may be part of an inductive heating system, wherein the aerosol generator or heater 120 is a source of energy for inductive heating, such as a coil of copper wire, and the substrate 110 may contain a susceptor or the like. The susceptor may, for example, be a sheet of aluminium foil or the like.

The aerosol generator or heater 120 may provide thermal energy, heat, to the surrounding environment of the aerosol generator or heater 120. At least some portion of the substrate 110 is within the area of effect of the aerosol generator or heater 120. The area of effect of the aerosol generator or heater 120 is the area within which the aerosol generator or heater 120 may provide heat to an item.

The arrangement shown in Fig. 1 may operate by indexing (or moving) the plurality of doses of aerosol generating material 114 relative to the aerosol generator or heater 120 with the benefit that only one aerosol generator or heater 120 is required to heat a plurality of portions of aerosol generating material 114. For example, the aerosol generator or heater 120 in the arrangement of Fig. 1 requires only one control mechanism as opposed to a plurality of heaters each requiring a separate control mechanism. As such, this arrangement can reduce the cost and control complexity in relation to the operation and control of the aerosol generator or heater 120.

The shape of the aerosol provision device 100 may be cigarette-shape (i.e. longer in one dimension than the other two) or may be other shapes. In an example, the aerosol provision device 100 may have a shape that is longer in two dimensions than the other one, for example like a compact-disc player or the like. Alternatively, the shape may be any shape that can suitably house the substrate 110, aerosol generator or heater 120, aerosol generating article 101 and the movement mechanism 130.

Fig. 2 illustrates a sectional view of an aerosol provision device 100 according to an embodiment and is similar to that shown in Fig. 1 , with additional features including specific individualised doses 114A,114B,114C of aerosol generating material and a warming element 200. The aerosol generator or heater 120 has a specific region of influence relevant to the substrate 110 referred to as the heating location 140. The heating location 140 may be located directly above the aerosol generator or heater 120. The heating location 140 is a region into which doses of aerosol generating material 114 are moved by the movement mechanism 130 to form an aerosol. This movement of the doses into the heating location 140 may occur prior to heating of a dose 114A, 114B,114C, 114D of aerosol generating material by the aerosol generator or heater 120. In the example shown in Fig. 2, a dose 114C of aerosol generating material has been moved into the heating region 140. The aerosol generator or heater 120 may heat the dose 114C in the heating region 140 to produce an aerosol. Conversely, the doses 114A,114B not located in the heating location 140 are located far enough away from the heating location 140 so as to not be heated by the aerosol generator or heater 120.

The aerosol generator or heater 120 may be activated after the dose 114C has been moved into the heating region 140. This arrangement has the advantage that energy is conserved during movement phases of the substrate 110. This leads to a longer operational life of the aerosol provision device 110, via length of life of a power source (not shown) to the aerosol generator or heater 120 and via length of life of the aerosol generator or heater 120 itself.

In another example, the aerosol generator or heater 120 may be activated prior to the dose 114C being moved into the heating region 140. This arrangement has the advantage that a warm up period is not required for the aerosol generator or heater 120 to reach a temperature suitable for inducing aerosolisation of an aerosol generating material once the dose 114C arrives in the heating region 140. As such, the delivery of aerosol to a user inhaling on the aerosol provision device 100 occurs more quickly and therefore improves the user experience of the aerosol provision device 100. In this arrangement, the aerosol generator or heater 120 can be brought to an operational temperature suitable for aerosolising the aerosol generating material prior to the dose 114C being moved into the heating region 140, or the aerosol generator or heater 120 can be brought to a pre-heat temperature (i.e. a temperature between ambient and operational) prior to the dose 114C being moved into the heating region 140 and subsequently raised to the operational temperature after the dose 114C has been moved into the heating region 140.

Referring still to Fig. 2, the aerosol provision device 100 has a movement mechanism 130 for enabling movement of the doses 114A,114B,114C, 114D. The movement mechanism 130 in the example shown in Fig. 2 includes a connecting element 132 which is arranged to connect to substrate 110 by connecting element 132. The movement mechanism 130 may include a rotating element around which the substrate 110 can rotate, such as a ball bearing. In an example, the substrate 110 is positioned on the bearing of the movement mechanism 130 and can be rotated by a user or a rotating system (e.g. motor and shaft) contained within the aerosol provision device 100. The movement mechanism 130 may be arranged substantially centrally in the substrate 110 as shown schematically in Fig. 2, or alternatively arranged in a different relative position to the substrate 110. Centrally locating the movement mechanism 130 provides the benefit of a clear central axis A (see Fig. 1) through the centre of the substrate 110 around which the substrate 110 may rotate as a result of the movement mechanism 130. Location of the movement mechanism 130 with respect to the substrate 110 may alternatively or additionally be determined in part by a desire to balance the substrate 110 on the portion of the movement mechanism 130 connected to the substrate 110. This arrangement, which may omit the connecting element 132, has the benefit of not requiring additional structures to balance the substrate 110 within the aerosol provision device 100, such as struts or guides.

Alternatively, additional structures may be used to allow the movement mechanism 130 to be located in any position relative to the substrate 110. Any such arrangement wherein the axis A (around which the substrate 110 may rotate) is off- centre to the central axis of the substrate 110 is possible, but may require intelligent arrangement of the doses of aerosol generating material on the substrate 110 alongside positioning of the aerosol generator or heater 120. The additional structures may project from the sides of the housing of the aerosol provision device 100 and assist in fixing the substrate 110 in place, while allowing motion of the substrate 110.

The movement mechanism 130 and connecting element 132 may take the form of a rotatable shaft which is driven by a motor around a bearing, and a sprocketing and/or keying mechanism arranged to connect with the substrate 110. In this case, the motor is used to drive the rotatable shaft 132, while the bearing of the movement mechanism 130 supports the shaft and facilitates rotational movement of the shaft 132. The substrate 110 and connecting element 132 may be provided with a keying and alignment feature combination which allows the substrate 110 to be connected to the connecting element 132. Alternatively, the force to move the movement mechanism 130 may be supplied by a user, for example by manually moving the substrate 110. This manual movement may be by rotating the substrate 110 or pulling the substrate 110 or the like. Accordingly, the aerosol provision device 100 may expose at least a part of the substrate 110 for the user to physically contact and move the substrate 110 e.g. an opening may be provided to expose a part of the circumferential edge of the substrate 110. The movement provided by the movement mechanism 130 is not restricted to rotational movement. Linear movement and oscillatory movement, among others, may also be provided. Arrangements to provide such movements are well known. The substrate 110 may be rotated via the movement mechanism 130 at a rotational speed which can be variable or consistent. A consistent movement provides the user with a substantially consistent level of aerosol production, as the substrate 110 consistently turns and so provides fresh aerosol forming material to the aerosol generator or heater 120. The rate at which aerosol is generated may depend on the rotational speed of the substrate 100, in addition to other parameters such as the temperature of the heater.

Alternatively, the substrate 110 may be rotated via the movement mechanism

130 at a variable rotational speed. In this example, the aerosol provision device 100 can provide greater or lesser amounts of aerosol as desired by the user by using a greater or lesser rotational speed. Use of varying rotational speeds may be used in conjunction with a variable heating profile from the aerosol generator or heater 120. The movement mechanism 130 may also provide indexed movement, such that the substrate 110 moves in a discretised manner. That is, the substrate 110 is arranged to move to pre-set angular positions. The amount by which the substrate 110 moves per indexed position may be consistent throughout the rotation of the substrate 110 (i.e. , over 360 degrees) or variable.

Fig. 2 also shows a warming element 200 arranged above the heating location 140 together with an air inlet 201 and an aerosol outlet 202. The aerosol provision device 100 comprises a chamber 190 in which the warming element 200 is provided. An aerosol generating article 101 is received within a reception region 225 within the aerosol provision device 100. The reception region 225 is located between the aerosol generator or heater 120 and the warming element 200. The aerosol outlet 202 provides an outlet through which an aerosol can flow to be inhaled by a user. The aerosol outlet 202 allows for aerosol generated within the aerosol provision device 100 to exit the aerosol provision device 100. In this way, a user inhaling on the aerosol outlet 202 may inhale an aerosol generated from the heating of doses 114A,114B,114C of aerosol generating material. The outlet 202 may be in the form of a mouthpiece or the like that is comfortable for a user to inhale on.

Arranged substantially between the aerosol generator or heater 120, the heating location 140 and the aerosol outlet 202, as shown in Fig. 2, the aerosol provision device 100 has a flow path 160. The flow path 160 is a route along which aerosol generated in the aerosol provision device 100, formed from the heated doses, flows to exit the aerosol provision device 100. The flow path 160 (i.e. the distance between the dose that is being heated and the outlet 202) may be relatively short so that the area on the inside of the aerosol provision device 100 on which the aerosol may might otherwise condense is reduced. This improves the overall cleanliness of the functioning of the aerosol provision device 100, resulting in a reduction in the frequency with which the aerosol provision device 100 must be cleaned.

As will be discussed in more detail below, the warming element 200 is provided in order to prevent or at least substantially reduce the likelihood of aerosol generated from the doses condensing within the chamber 190. The warming element 200 may comprise a plate or surface of ferritic material which may be heated to a temperature of e.g. 60- 150 °C during a session of use. The warming element 200 may be warmed by receiving a time varying magnetic field generated by one or more induction coils which may comprise the aerosol generator or heater 120. In alternative embodiments the warming element 200 may be heated by a warming unit (not shown) which may comprise either one or more resistive heaters and/or one or more inductive heaters which are separate from and distinct to the aerosol generator or heater 120. The warming element 200 may comprise a thin plate, coating or foil which may have a thickness < 25 pm.

As the aerosol passes over fewer components along the relatively short flow path out of the aerosol provision device 100, fewer components may be affected by aerosol condensing on them and therefore the components need to be replaced less frequently. This reduces the cost of maintenance of the aerosol provision device 100 and increases the lifetime of the overall aerosol provision device 100.

Although in Fig. 2 the aerosol outlet 202 is shown offset from the centre of the aerosol provision device 100, in some implementations the aerosol outlet 202 may be more central. In yet further implementations, the aerosol outlet 202 may be positioned broadly in line with the dose that is being heated and/or the aerosol generator or heater 120 (e.g. a central axis of the outlet may be aligned with the normal to the dose). This may further reduce the flow path 160.

According to various embodiments the aerosol generator or heater 120 may be fixed and the substrate 110 may be moved e.g. rotated relative to the aerosol generator or heater 120. However, in other embodiments the aerosol generator or heater 120 may be movable.

With reference to Fig. 3, an aerosol provision device 100 according to various embodiments is shown wherein the aerosol generator or heater 120 may be moved relative to the substrate 110 in order to improve the thermal delivery from the aerosol generator or heater 120 to the aerosol generating material. The aerosol generator or heater 120 may be moved, for example, towards or away from the substrate 110 as a specific dose is moved, or has been moved, into the heating location 140. Moving the aerosol generator or heater 120 towards the dose to be heated reduces the separation between the aerosol generator or heater 120 and the substrate 110. The aerosol provision device 100 comprises a chamber 190 and a reception region 225 for receiving an aerosol generating article 101. The reception region 225 is arranged between the aerosol generator or heater 120 and the warming element 200.

The aerosol generator or heater 120 may comprise an inductive heater (i.e. an RF generator) and the inductive heating may be improved by reducing the distance between the RF generator and the substrate 110 which comprises a susceptor. The susceptor may comprise a thin aluminium foil having a thickness < 10 pm.

If the aerosol generator or heater 120 comprises a resistive heater then there is an air jacket between the resistive heater 120 and the aerosol generating material which would otherwise absorb heat energy from the resistive heater 120 and therefore reduce the heat energy provided to the aerosol generating material. Instead, by reducing the air jacket, the resistive heater 120 delivers heat energy more efficiently to the aerosol generating material in the heating location 140. In the example of Fig. 3, the aerosol generator or heater 120 may be moved linearly towards or away from the substrate 110.

In an example, the aerosol generator or heater 120 may be moved into contact with the rear surface of the substrate 110 in order to optimise the heating of a specific dose of aerosol generating material. After one specific dose is heated, the doses may be moved (e.g. rotated) so that a fresh dose may be moved into the heating location 140. In instances where the aerosol generator or heater 120 contacts the substrate 110, prior to moving the doses , so as to move a new specific dose into the heating location 140, the aerosol generator or heater 120 may be moved away from (or out of contact with) the substrate 110 in order to prevent friction which would otherwise occur during the movement of the doses if the aerosol generator or heater 120 remained in close contact with the rear surface of the substrate 110 at all times during a session of use.

However, embodiments are also contemplated wherein the substrate 110 remains in contact with the aerosol generator or heater 120 which may comprise either an inductive or a resistive heater throughout the whole of a session of use.

With reference to Figs. 1 and 2, the angle 0 between the axis of rotation A and the lower surface of the substrate 110 is substantially perpendicular. In other examples, the angle 0 may be at least 5°, at least 10°, at least 15°, at least 20°, at least 25°, at least 30°, at least 35°, at least 40°, at least 45°, at least 50°, at least 55°, at least 60°, at least 65°, at least 70°, at least 75°, at least 80° or at least 85°.

With reference to Fig. 2, the aerosol provision device 100 may comprise a controller 172 for monitoring and/or controlling movement provided by the movement mechanism 130. The controller 172 may control the movement of the doses of aerosol generating material 114A,114B,114C such that doses are controllably moved into the heating location 140. The controller 172 may also be able to inform the user on the number of remaining viable doses in the aerosol provision device 100. In an example, the aerosol provision device 100 may have a motion monitoring system 170 which comprises the controller 172 (e.g. as shown in Fig. 2) and optionally a detector 174.

The monitoring system 170 may monitor the motion within the aerosol provision device 100. The monitoring system 170 may also comprise a detector 174 for detecting movement information. The monitoring system 170 monitors the motion of the substrate 110 and/or the doses of aerosol generating material 114A,114B,114C to record movement that has occurred and thereby avoids moving the same specific dose into the heating location 140 twice. This avoids undesired aerosol being formed from reheating of a “spent” dose. The detector 174 may relay to the user information relating to the number of “unspent” doses remaining in the aerosol provision device 100, so that the user is informed when to replace the plurality of doses within the aerosol provision device 100. The detector 174 can also provide feedback on the functioning of the movement mechanism 130 by observing the movement of the substrate 110 or doses or the aerosol generator or heater 120, so as to inform a user if the movement mechanism 130 (or any associated element, e.g. connecting element 132) malfunctions.

The controller 172 may comprise a microcontroller so as to reduce space requirements. The detector 174 may be a break beam sensor, brushed system, speed tracker or the like to provide information on e.g. the number of rotations of the substrate 110 and the locations of the substrate 110 which have been moved to the heating location 140. This information may be relayed to a user or to a diagnostics element (not shown) to enable regular checks on the functioning of the aerosol provision device. The motion monitoring system 170 may be connected to the movement mechanism 130 by a wired connection such as a simple electrical connection or any other connection including wireless such as Bluetooth etc.

Fig. 3 illustrates a sectional view of a portion of an aerosol provision device 100 according to an embodiment. Fig. 3 shows an enlarged view of the portion of the aerosol provision device 100 including a substrate 110 which forms part of an aerosol generating article 101 received within the aerosol provision device 100, an aerosol generator or heater 120, an aerosol outlet 202 and a flow path 160. The substrate 110 may rotated so that different portions of the substrate 110 are sequentially position adjacent the aerosol generator or heater 120. The aerosol provision device 100 comprises a chamber 190 and a reception region 225 for receiving an aerosol generating article 101. The reception region 225 is arranged between the aerosol generator or heater 120 and the warming element 200.

The general direction B of movement of the aerosol along the flow path 160 is shown by arrow B. The difference between the plane of the surface of the substrate 110 and the direction of the flow path 160 of the resulting aerosol is indicated by the angle <t>. The angle is somewhat controlled by the relative locations of the aerosol generator or heater 120 and the aerosol outlet 202. In the example shown, the heating location 140 is arranged substantially between the aerosol outlet 202 and the aerosol generator or heater 120. The aerosol outlet 202 may be arranged substantially in line with the aerosol generator or heater 120 and the heating location 140 such that the angle is substantially 90°. In other examples, the angle may be at least 5°, at least 10°, at least 15°, at least 20°, at least 25°, at least 30°, at least 35°, at least 40°, at least 45°, at least 50°, at least 55°, at least 60°, at least 65°, at least 70°, at least 75°, at least 80°, at least 85°.

According to various embodiments a warming element 200 is provided between the substrate 110 and the aerosol outlet 202. The warming element 200 may comprise a planar surface which may be inclined at an angle a to the surface of the substrate 110. According to various embodiments the angle a may be < 10°, 10-20°, 20-30°, 30-40°, 40- 50°, 50-60°, 60-70°, 70-80° or 80-90°. According to other embodiments the warming element 200 may be curved. For example, the warming element 200 may have a convex or concave shape. The warming element 200 may have one or more points of inflection.

The arrangement shown in Fig. 3 simplifies the flow path 160 taken by the aerosol, which in turn reduces the amount of time the aerosol is in the aerosol provision device 100. This arrangement therefore reduces the area on the inside of the aerosol provision device 100 on which the aerosol could potentially condense, and the time during which it can condense. This therefore decreases the impact of any associated problems of intra-device aerosol condensation.

Furthermore, as will be discussed in more detail below the warming element 200 is provided in order to substantially reduce or prevent aerosol condensing within the chamber 190. The warming element 200 may comprise a plate of ferritic material which may be heated to a temperature of e.g. 60-150 °C during a session of use. The warming element 200 may be warmed by receiving a time varying magnetic field generated by one or more induction coils which may comprise the aerosol generator or heater 120. In alternative embodiments the warming element 200 may be heated by a warming unit (not shown) which may comprise either one or more resistive heaters and/or one or more inductive heaters which are separate from and distinct to the aerosol generator or heater 120. The warming element 200 may comprise a thin plate, coating or foil which may have a thickness < 25 pm.

The substrate 110 and/or the plurality of doses of aerosol generating material may be substantially in the form of a number of shapes. According to an embodiment the substrate 110 may be in the form of a circular disk or ring. The substrate 110 may take these shapes when installed in the aerosol provision device 100 and be the same or a different shape when not in the aerosol provision device 100. In other words, the substrate 110 may be deformed to take a certain shape different from its initial shape when installed in the aerosol provision device 100. The substrate 110 may have an alignment mechanism or a keying mechanism to enable the substrate 110 to be aligned with a movement mechanism and to then connect to the movement mechanism. In some implementations, the alignment mechanism or keying mechanism is arranged such that the substrate 110 can only be aligned in one orientation with the movement mechanism e.g. by having a shape without a degree of symmetry.

According to various embodiments the aerosol generating material may be moved past an aerosol generator or heater 120. This movement may be provided by a movement mechanism 130 as shown in Fig. 2. The movement mechanism 130 may comprise an indexing system (not shown) arranged to enable indexed motion of the doses of aerosol generating material. The indexing system moves a specific dose in a stepwise manner into the heating location 140 prior to generating an aerosol from that specific dose and then out of the heating location 140 after having generated an aerosol. The indexing system may enable greater precision of movement of one dose into the heating location 140, that dose then being replaced by another dose. The indexing system can be provided by sprocketing and/or a keying mechanism arranged on, or forming part of, the substrate 110. In alternative examples, a Geneva wheel and cam combination can be used to provide an indexed motion of the doses of aerosol generating material.

The indexing system may be arranged to move adjacent doses of aerosol generating material into the heating location 140 in turn. An advantage of this arrangement is that the indexing system is simple to construct and operate. In an arrangement wherein adjacent doses are heated in turn, energy can be saved by heating a second dose due to the heat energy transferred by virtue of proximity to the second dose during heating of a first dose. This can in turn, reduce the total load on the aerosol generator or heater 120 and therefore increase the lifetime of the aerosol provision device 100.

Alternatively, the indexing system may be arranged to move only non-adjacent doses of aerosol generating material into the heating location 140 in turn. This enables a high density of doses to be arranged on the substrate 110 without the danger of overheating any particular dose due to overly high levels of indirect heat (heat indirectly transferred to the dose during heating of a preceding dose) followed by direct heat (heat provided to the dose during the heating of that same dose). Each dose may contain a prescribed amount of nicotine and/or aerosol forming components, and supplying energy at the incorrect time can cause nicotine and/or aerosol forming components from that dose to be released at an earlier time than intended. Alternatively, spent doses can be re-heated after the nicotine and/or aerosol forming components are released which can lead to other components of the dose being heated. However, the described arrangement removes any need for a sophisticated heating control system which provides variations in time or heating power for specific doses so as to prevent overheating.

The indexing system may be observed by the monitoring system 170, using techniques as described above. This enables checks on the functionality of the indexing system to ensure the system is working as expected. In any of the above-described arrangements, the monitoring system 170 may be used to assist in preventing overheating of any specific dose.

The movement mechanism 130 and monitoring system 170 can operate in combination with the aerosol generator or heater 120 to ensure that indexed movements of the doses and the heating periods for any specific dose are coordinated to prevent overheating of a dose. The movement mechanism 130 may be arranged to present one dose of aerosol generating material to the aerosol generator or heater 120 for a period of time and present another dose of aerosol generating material to the aerosol generator or heater 120 for a different period of time. This may be so as to provide different heating levels to different doses. This may be advantageous in avoiding overheating in the event of linear indexing as mentioned above. This may also be advantageous when one dose of aerosol generating material is of a different structure or substance to another dose such that different heating periods are required to generate an aerosol.

The movement mechanism 130 and monitoring system 170 can operate in combination with the aerosol generator or heater 120 to ensure that indexed movements of the doses 114 and the heater power levels for any specific dose 114 are coordinated. This may be so as to provide different heating levels to different doses. This may be advantageous in avoiding overheating in the event of linear indexing, or high density dose provision. For example, the heater power level could be high for a first dose and then less high for a second dose. This is advantageous as the second dose will have received some level of indirect heat during the heating of the first dose, such that a second dose requires less direct heating (achieved by reducing the power level of the heater) to provide an aerosol. This may also be advantageous when one dose of aerosol generating material is of a different structure or substance to another dose, such that different heater power levels are required to generate an aerosol.

Aerosol generating material is a material that is capable of generating aerosol, for example when heated, irradiated or energized in any other way. Aerosol generating material may, for example, be in the form of a solid, liquid or semi-solid (such as a gel) which may or may not contain an active substance and/or flavourants.

The aerosol generating material may comprise one or more active substances and/or flavours, one or more aerosol-former materials, and optionally one or more other functional material.

The aerosol generating material may comprise a binder, such as a gelling agent, and an aerosol former. Optionally, a substance to be delivered and/or filler may also be present. Optionally, a solvent, such as water, is also present and one or more other components of the aerosol generating material may or may not be soluble in the solvent. In some embodiments, the aerosol generating material is substantially free from botanical material. In particular, in some embodiments, the aerosol generating material is substantially tobacco free.

The aerosol generating material may comprise or be in the form of an aerosol generating film. The aerosol generating film may comprise a binder, such as a gelling agent, and an aerosol former. Optionally, a substance to be delivered and/or filler may also be present. The aerosol generating film may be substantially free from botanical material. In particular, in some embodiments, the aerosol-generating material is substantially tobacco free. The aerosol generating film may have a thickness of about 0.015 mm to about 1 mm. For example, the thickness may be in the range of about 0.05 mm, 0.1 mm or 0.15 mm to about 0.5 mm or 0.3 mm. The aerosol generating material may comprise more than one film, and the thickness described herein may refer to the aggregate thickness of those films. The aerosol generating film may be continuous. For example, the film may comprise or be a continuous sheet of material. The sheet may be in the form of a wrapper, it may be gathered to form a gathered sheet or it may be shredded to form a shredded sheet. The shredded sheet may comprise one or more strands or strips of aerosol-generating material.

The aerosol generating film may be discontinuous. For example, the aerosolgenerating film may comprise one or more discrete portions or regions of aerosolgenerating material, such as dots, stripes or lines, which may be supported on a support. In such embodiments, the support may be planar or non-planar. The aerosol generating film may be formed by combining a binder, such as a gelling agent, with a solvent, such as water, an aerosol-former and one or more other components, such as one or more substances to be delivered, to form a slurry and then heating the slurry to volatilise at least some of the solvent to form the aerosol-generating film. The slurry may be heated to remove at least about 60 wt%, 70 wt%, 80 wt%, 85 wt% or 90 wt% of the solvent.

In some cases, the aerosol generating material may comprise 1-50wt% of a gelling agent wherein these weights are calculated on a dry weight basis. Suitably, the aerosol generating material may comprise from about 1wt%, 5wt%, 10wt%, 15wt%, 20wt% or 25wt% to about 50wt%, 45wt%, 40wt%, 35wt%, 30wt% or 27wt% of a gelling agent (all calculated on a dry weight basis). For example, the aerosol generating material may comprise 5-40wt%, 10-30wt% or 15-27wt% of a gelling agent. In some cases, the aerosol generating material comprises a tobacco extract. In some cases, the aerosol generating material may comprise 5-60wt% (calculated on a dry weight basis) of tobacco extract. In some cases, the aerosol generating material may comprise from about 5wt%, 10wt%, 15wt%, 20wt% or 25wt% to about 55wt%, 50wt%, 45wt% or 40wt% (calculated on a dry weight basis) tobacco extract. For example, the aerosol generating material may comprise 5-60wt%, 10-55wt% or 25-55wt% of tobacco extract. The tobacco extract may contain nicotine at a concentration such that the aerosol generating material comprises 1wt% 1.5wt%, 2wt% or 2.5wt% to about 6wt%, 5wt%, 4.5wt% or 4wt% (calculated on a dry weight basis) of nicotine. In some cases, there may be no nicotine in the aerosol generating material other than that which results from the tobacco extract. In some embodiments the aerosol generating material comprises no tobacco material but does comprise nicotine. In some such cases, the aerosol generating material may comprise from about 1wt%, 2wt%, 3wt% or 4wt% to about 20wt%, 15wt%, 10wt% or 5wt% (calculated on a dry weight basis) of nicotine. For example, the aerosol generating material may comprise 1-20wt% or 2-5wt% of nicotine. The aerosol generating material may comprise less than 20wt%, suitably less than 10wt% or less than 5wt% of a filler. The filler may comprise one or more inorganic filler materials, such as calcium carbonate, perlite, vermiculite, diatomaceous earth, colloidal silica, magnesium oxide, magnesium sulphate, magnesium carbonate, and suitable inorganic sorbents, such as molecular sieves. The filler may comprise one or more organic filler materials such as wood pulp, cellulose and cellulose derivatives. In some cases, the aerosol generating material comprises less than 1wt% of a filler, and in some cases, comprises no filler. In particular, in some cases, the aerosol generating material comprises no calcium carbonate such as chalk.

In some cases, the aerosol generating material may consist essentially of, or consist of a gelling agent, an aerosol generating agent, a tobacco material and/or a nicotine source, water, and optionally a flavour. It should be appreciated that the aerosol generating material may be any other suitable aerosol generating material as deemed appropriate by the skilled person.

Referring to Fig. 4, an example of an arrangement of portions of aerosol generating material 114A,114B,114C,114D provided on a rounded substrate 110 is shown. The portions 114A,114B,114C, 114D are arranged in concentric rings which may be heated in order via rotational indexing of the substrate 110, followed by lateral indexing of an aerosol generator or heater so as to heat the next ring in the sequence of concentric rings. This indexing sequence may be repeated until each dose 114A,114B,114C,114D is heated to produce aerosol. The indexing provided to the substrate 110 may be even or uneven in distance and/or time. In an example, the final portion 114D to be heated may be arranged towards the centre of the substrate 110. This portion 114D may, for example, be a portion 114D comprising a flavour such as menthol in order to provide a refreshing conclusion to a smoking session. A user may be able to personalise the smoking session through use of varying arrangements of aerosol generating material.

It should be understood that there is no restriction that the portions 114A,114B,114C,114D should be in an arrangement with rotational symmetry particularly with lateral movement of an aerosol generator or heater. According to various embodiments the doses 114A,114B,114C,114D may be arranged on the substrate 110 which may be substantially impermeable to aerosol. This arrangement encourages the aerosol generated from heating of the aerosol generating material doses 114A,114B,114C, 114D to flow away from the aerosol generator or heater and along a flow path towards an aerosol outlet. This reduces the likelihood of condensation of aerosol within the aerosol provision device and, as mentioned above, therefore increases both the cleanliness and lifetime of the aerosol provision device . The substrate 110 may be formed from a material such as paper, cardboard, wood pulp, plastic or ceramic etc.

The substrate 110 may be impermeable to aerosol or may be porous such that the aerosol forming material may be located in the pores of the substrate 110. In an example, the substrate 110 may have both permeable and impermeable portions. Permeable portions may be located in portions wherein it is desirable to have aerosol pass through the substrate 110, such as to allow air to flow through the substrate 110 and towards the outlet of the aerosol provision device 100. Impermeable portions may be located in portions wherein it is desirable to prevent aerosol flowing towards the aerosol generator or heater.

Fig. 5 shows a schematic top-down view of a portion of an aerosol provision device 100 according to an embodiment. The portion of the aerosol provision device 100 shows a substrate 110 having portions of aerosol generating material provided thereon received in a reception region of the aerosol provision device 100 and an aerosol generator or heater 120 comprising heating elements 120A,120B,120C which may be arranged below the substrate 110. The substrate 110 may be moved relative to the aerosol generator or heater 120 in order to move portions of aerosol generating material relative to the aerosol generator or heater 120 in order to produce an aerosol.

The aerosol generator or heater 120 may comprise a plurality of heating elements 120A,120B,120C. Alternatively, rather than one aerosol generator or heater 120 having a plurality of heating elements, a plurality of separate heaters 120A,120B,120C may be provided.

The aerosol generator or heater 120 may be activated by a power source so as to provide heat to the substrate 110. In use, the heating elements 120A,120B,120C of the aerosol generator or heater 120 may not be activated simultaneously. In an example, the heating elements 120A,120B,120C of the aerosol generator or heater 120 may be activated separately. The heating elements 120A,120B,120C may be activated in a sequence. In a specific example, the heating elements 120A,120B,120C may be activated one after the other in the order of a first heating element 120A, then a second heating element 120B, then a third heating element 120C. In the example shown in Fig. 5, the first heating element 120A is arranged most centrally with respect to the substrate 110, the second heating element 120B is arranged between the first heating element 120A and the third heating element 120C and the third heating element 120C is arranged towards the outer edge of the substrate 110. In an example, the first heating element 120A is activated to heat a portion of the substrate 110 proximal to the first heating element 120A. Subsequently, the second heating element 120B is activated to heat a different portion of the substrate 110, which is proximal to the second heating element 120B. Subsequently, the third heating element 120C is activated to heat another different portion of the substrate 110, which is proximal to the third heating element 120C. The order of the activated of the heating elements 120A,120B,120C may be varied based on the desired output of aerosol. The activation of the heating elements 120A,120B,120C may be controlled dependent upon the arrangement of the aerosol generating material on the substrate 110.

In the specific example shown in Fig. 5, the aerosol generator or heater 120 may comprise a triangular shaped aerosol generator or heater 120 which may have a rounded base. The base need not be rounded but may be shaped so as to provide a good coverage of the substrate 110. Good coverage is provided by a suitable sized aerosol generator or heater 120, which does not waste energy overly heating the environment around the substrate 110 while ensuring aerosol generating material on the substrate 110 may be heated. As such, different arrangements of substrate 110 and aerosol generator or heater 120 shapes can be envisaged. The heating elements 120A,120B,120C may be provided at different radial positions in the triangular aerosol generator or heater 120.

In an example, the first heating element 120A is activated for a first puff, the second heating element 120B is activated for a second puff and the third heating element 120C is activated for a third puff. After the final heating element is activated (in this three heating element example, this is the third heating element 120C), the substrate 110 may move relatively to the aerosol generator or heater 120 to present fresh aerosol generating material to the aerosol generator or heater 120.

The heating elements 120A,120B,120C may be different shapes or sizes. The heating elements 120A,120B,120C may occupy the same area or a different area. By this it is meant that, when viewed from e.g. a top view, the heating elements 120A, 120B, 120C may cover a relatively similar area of the substrate 110. Heating elements covering a similar area of a continuous disc (as shown) may provide for a similar aerosol volume to be produced per puff, thereby providing better consistency for the user.

The relative movement of the substrate 110 to the aerosol generator or heater 120 may be a stepwise (e.g. indexed) movement. The movement may be a fixed amount and may occur after each session of heating, where a session is the activation of each of the heating elements 120A,120B,120C. In this way, fresh aerosol generating material may be provided to the aerosol generator or heater 120 for heating to produce an aerosol. This arrangement reduces the likelihood of a portion of aerosol generating material being heated twice and producing undesirable compounds from overheating or burning.

Fig. 6 shows an aerosol generating article 101 according to an embodiment comprising a substrate 110 which has an annular shape with a central circular cut-out, aperture or hole 600. The aerosol generating article 101 may be received within a reception region of an aerosol provision device which may comprise an aerosol generator or heater which, for example, may comprise an inductive heater having an RF generator comprising a circular coil of wire. The RF generator is also known as an inductor coil. The wire may comprise LITZ (RTM) wire. The substrate 110 may comprise a backing material facing the RF generator onto which a thin aluminium foil or other metallic element is provided which acts as a susceptor. Aerosol generating material may be provided uniformly upon the aluminium foil or other metallic element. The aerosol generator or heater may be placed in close contact with the substrate 110 such that a circular heating region 601 is effectively formed in the substrate 110. The substrate 110 may be rotated about the aerosol generator or heater so that multiple puffs of aerosol are generated from a single substrate 110.

Fig. 7A shows a cross-sectional view through a schematic representation of an aerosol provision system 300 in accordance with another embodiment. The aerosol provision system 300 comprises two main components, namely an aerosol provision device 203 and an aerosol generating article 204 received within the aerosol provision device 203.

The aerosol provision device 203 comprises an outer housing 221 , a power source 222, control circuitry 223, one or more aerosol generators or heating elements 224a, a reception region 225 for receiving an aerosol generating article 204, a mouthpiece end 226, an air inlet 227, an air outlet 228, a touch-sensitive panel 229, an inhalation sensor 230 and an end of use indicator 231. The reception region 225 is located between one or more aerosol generators or heating elements (which may comprise inductor coils 224a) and a warming element 200.

The reception region 225 is sized such that an aerosol generating article 204 may be received and optionally secured in the reception region 225. Although not shown, the aerosol provision device 203 may comprise a hinged door or removable part of the outer housing 221 to permit access to the reception region 225 such that a user may insert and/or remove the aerosol generating article 204 from the reception region 225.

The hinged door or removable part of the outer housing 221 may also act to retain the aerosol generating article 204 within the reception region 225 when closed. When the aerosol generating article 204 is exhausted or the user simply wishes to switch to a different aerosol generating article 204, the aerosol generating article 204 may be removed from the aerosol provision device 203 and a replacement aerosol generating article 204 may be positioned in the reception region 225 in its place.

Alternatively, the aerosol provision device 203 may include a permanent opening that communicates with the reception region 225 and through which the aerosol generating article 204 can be inserted into the reception region 225. In such implementations, a retaining mechanism for retaining the aerosol generating article 204 within the reception region 225 of the aerosol provision device 203 may be provided. According to various embodiments at least a part of the portion of the housing 221 may face inwards to partially define the reception region 225 and this portion may comprise a warming element 200.

According to an embodiment, and as indicated by the dashed lines and shaded region in Fig. 7 A, substantially the entirety of the part of the reception region 225 furthest away from the aerosol generating components 224 may be formed as a warming element 200 such that, in use, an aerosol generating article 204 is positioned between the one or more aerosol generators or heating elements 224a and the warming element 200. As explained in more detail both above and below, the warming element 200 helps reduce or substantially prevent condensate forming on the walls of the reception region 225 and elsewhere within the aerosol provision device 203.

The warming element 200 may comprise ferritic material which may be heated to a temperature of e.g. 60-150 °C during a session of use. The warming element 200 may be warmed by interacting with a time varying magnetic field generated by one or more induction coils 224a and wherein the one or more induction coils 224a form part of one or more aerosol generators or heating elements.

In alternative embodiments the warming element 200 may be heated by a warming unit (not shown) which may comprise one or more resistive heaters and/or one or more inductive heaters. The warming unit (not shown) may be located in close proximity to the warming element 200 and may be located closer to the warming element 200 than the induction coils 224a or more generally the one or more aerosol generators or heating elements 224a. The warming element 200 may have a thickness < 25 pm.

The outer housing 221 may be arranged such that the power source 222, control circuitry 223, one or more aerosol generators or heating elements 224a, reception region 225 and inhalation sensor 230 are located within the outer housing 221. The outer housing 221 also defines the air inlet 227 and air outlet 228. The touch sensitive panel 229 and end of use indicator are located on the exterior of the outer housing 221. The power source 222 is configured to provide operating power to the aerosol provision device 203. The power source 222 may be any suitable power source, such as a battery. For example, the power source 222 may comprise a rechargeable battery, such as a Lithium Ion battery. The power source 222 may be removable or form an integrated part of the aerosol provision device 203. In some implementations, the power source 222 may be recharged through connection of the device 203 to an external power supply (such as mains power) through an associated connection port, such as a USB port (not shown) or via a suitable wireless receiver (not shown).

The aerosol generating article 204 may comprise a carrier component or substrate 242, aerosol generating material 244 and susceptor elements 244b.

Fig. 7B is a top-down view of the aerosol generating article 204, Fig. 7C is an end-on view along the longitudinal (length) axis of the aerosol generating article 204 and Fig. 7D is a side-on view along the width axis of the aerosol generating article 204.

Figs. 7A-7D represent an aerosol provision system 300 which uses induction to heat the aerosol generating material 244 in order to generate an aerosol for inhalation. However, as discussed above, the aerosol provision system 300 may instead or additionally use resistive heating to heat the aerosol generating material 244. In such embodiments, the components labelled 224a in Fig. 7A may comprise resistive heating elements.

In the described implementation, an aerosol generating component 224 may be formed of two parts i.e. one or more induction heating elements such as inductor coils 224a which are located in the aerosol provision device 203 and one or more susceptors 224b which are located in the aerosol generating article 204. The one or more inductor coils 224a need not be a circular coil of wire. For instance, in embodiments, the induction heating elements may comprise one or more of: (i) a flat spiral coil, wherein the spiral coil comprises a circular or ovular spiral, a square or rectangular spiral, a trapezoidal spiral, or a triangular spiral; (ii) a multi-layered induction arrangement wherein subsequent full or partial turns of a coil are provided on adjacent layers, optionally wherein a first layer is spaced from a second layer in a first direction and a third layer is spaced from the second layer in the opposite direction to reside in or close to the first layer such that the multi-layered induction arrangement forms a staggered structure; or (iii) a three- dimensional inductor coil, such as a regular helix or a conically shaped inductor coil, optionally with a varying helical pitch.

As seen in Figs. 7C and 7D, the carrier component or substrate 242 may comprise one or more susceptors 224b which may correspond in size and location to the discrete portions of aerosol generating material 244 disposed on the surface of the carrier component or substrate 242. That is, the susceptors 224b have a similar width and length to the discrete portions of aerosol generating material 244. The susceptors are shown embedded in a carrier component or substrate 242. However, in other implementations, the susceptors 224b may be placed on the surface of a carrier component or substrate 242. In another implementation (not shown), a susceptor may be provided as a layer substantially covering the carrier component or substrate 242. For example, the susceptor may comprise a metallic foil. According to an embodiment the susceptor may comprise an aluminium foil.

The aerosol provision device 203 may comprise one or more inductor coils 224a as shown schematically in Fig. 7A. Inductor coils 224a are shown adjacent the reception region 225, and may comprise generally flat coils arranged such that the rotational axis about which a given coil is wound extends into the reception region 225 (e.g. parallel with the z-axis as indicated in Fig. 7A) and is broadly perpendicular to the plane of the carrier component or substrate 242 of the aerosol generating article 204. The exact windings are not shown in Fig. 7A and it should be appreciated that any suitable induction coil may be used. As will be understood, the warming element 200 may be configured so as to be penetrated by a proportion of the varying magnetic flux (generated by the inductor coils 224a) which has not been absorbed by the susceptor(s) 224b provided as part of the aerosol generating article 204. According to an embodiment the warming element 200 may be penetrated by < 10%, 10-20%, 20-30%, 30-40%, 40-50%, 50-60%, 60-70%, 70- 80%, 80-90% or > 90% of the time varying magnetic flux generated by the one or more inductor coils 224a.

Fig. 7E is a cross-sectional, top-down view of the aerosol provision device 203 showing the arrangement of the aerosol generators or heating elements 224a-f in more detail. The aerosol generators or heating elements 224a-f are arranged such that, when the aerosol generating article 204 is received in the reception region 225, each aerosol generator or heating element 224a-f aligns with a corresponding discrete portion of aerosol generating material 244a-f. Hence, in this example, six aerosol generators or heating elements 224a-f are arranged in a two by three array broadly corresponding to the arrangement of the two by three array of the six discrete portions of aerosol generating material 244a-f as shown in Figs. 7A-7D. However, as discussed above, the number of aerosol generators or heating elements 224a-f may be different in different implementations, for example 8, 10, 12, 14, etc. aerosol generators or heating elements 224a-f may be provided. In some implementations, the number of aerosol generators or heating elements 224a-f may be greater than or equal to six but no greater than 20. Each of the aerosol generators or heating elements 224a-f can be individually activated to heat a corresponding portion of aerosol generating material 244a-f.

In some embodiments, each inductor coil 224a may have a generally trapezoidal shape, as shown in Figs. 8A and 8B and as will be described in more detail below. Figs. 8A and 8B show two different examples of a substantially planar or flat inductor coil. Fig. 8A shows a trapezoid shaped inductor arrangement 1000. The trapezoid shaped inductor arrangement may comprise an electrically-conducting track 1001 which may comprise a copper track. As shown, the electrically-conducting track 1001 may form an inductor coil in a substantially trapezoidal shape, wherein the substantially trapezoidal shape comprises a first angled side 1002, a second angled side 1003, a long side 1004 and a short side 1005. The short side 1005 is shorter in length than the long side 1004.

Referring to Fig. 8B, there is shown an embodiment of a substantially planar inductor coil comprising a layered inductor arrangement 90, wherein the layered inductor arrangement 90 comprises a two-layer bifilar coil inductor arrangement 90 comprising a first layer 91 and a second layer 92. The layered inductor arrangement 90 of Fig. 9B is shown as a trapezoid shaped inductor arrangement. However, other embodiments are contemplated wherein the layered inductor arrangement may have a different shapes such as, for example, circular, square, rectangular etc.

Other embodiments are contemplated wherein the layered inductor arrangement 90 may be irregularly shaped. The layered inductor arrangement may comprise a first layer 91 which may comprise one or more first electrically-conductive wires or tracks 91a and the second layer 92 which may comprise one or more second electrically-conductive wires or tracks 92a. The first 91a and second 92a electrically-conductive wires or tracks may be concentric and substantially over-lapping. One or more electrically-conductive linking portions 93 may be provided which electrically connect one or more of the first electrically-conductive wires or tracks 91a provided on the first layer 91 to one or more second electrically-conductive wires or tracks 92a provided on the second layer 92.

The layered inductor arrangement 90 may be formed in a PCB format, wherein the vertical plane may be used to stack layers of inductor elements. Furthermore, the low aspect ratio in terms of the height of the copper tracks to the width of the copper tracks results in a compact inductor arrangement. It has been found that coupling the wires or tracks vertically instead of horizontally further enhances the mutual coupling or capacitive linking of the wires, while minimising any phase shift between them.

As will be understood, induction heating is a process in which an electrically- conductive object, referred to as a susceptor, is heated by penetrating the object with a varying magnetic field. The process is described by Faraday's law of induction and Ohm's law. An induction heater may comprise an electromagnet and a device for passing a varying electrical current, such as an alternating current, through the electromagnet. When the electromagnet and the object to be heated are suitably relatively positioned so that the resultant varying magnetic field produced by the electromagnet penetrates the object, one or more eddy currents are generated inside the object. The object has a resistance to the flow of electrical currents. Therefore, when such eddy currents are generated in the object, their flow against the electrical resistance of the object causes the object to be heated. This process is called Joule, ohmic, or resistive heating.

A susceptor is material that is heatable by penetration with a varying magnetic field, such as an alternating magnetic field. The susceptor may be an electrically- conductive material, so that penetration thereof with a varying magnetic field causes induction heating of the heating material. The heating material may be magnetic material, so that penetration thereof with a varying magnetic field causes magnetic hysteresis heating of the heating material. The susceptor may be both electrically- conductive and magnetic, so that the susceptor is heatable by both heating mechanisms. The device that is configured to generate the varying magnetic field is referred to as a magnetic field generator, herein.

Magnetic hysteresis heating is a process in which an object made of a magnetic material is heated by penetrating the object with a varying magnetic field. A magnetic material can be considered to comprise many atomic-scale magnets, or magnetic dipoles. When a magnetic field penetrates such material, the magnetic dipoles align with the magnetic field. Therefore, when a varying magnetic field, such as an alternating magnetic field, for example as produced by an electromagnet, penetrates the magnetic material, the orientation of the magnetic dipoles changes with the varying applied magnetic field. Such magnetic dipole reorientation causes heat to be generated in the magnetic material.

When an object is both electrically-conductive and magnetic, penetrating the object with a varying magnetic field can cause both Joule heating and magnetic hysteresis heating in the object. Moreover, the use of magnetic material can strengthen the magnetic field, which can intensify the Joule heating.

In the described implementation, the susceptors 224b may be formed from an aluminium foil, although it should be appreciated that other metallic and/or electrically conductive materials may be used in other implementations.

Fig. 9 shows an aerosol provision device 100 according to an embodiment wherein a warming element 200 is provided in the region where aerosol will be generated from an aerosol generating article. The aerosol provision device 100 is arranged to generate aerosol from aerosol generating material which is provided on an aerosol generating article which may comprise a substrate 110. The aerosol generating article including a substrate 110 is received into a reception region 225 of the aerosol provision device 100 which is located in close proximity to an aerosol generator or heater 192. The aerosol generator or heater 192 is provided on one side of the reception region 225 and one or more warming elements 200 are provided on the other side of the reception region 225. The aerosol provision device 100 may comprise a plurality of aerosol generators or heaters 192, wherein at least some or each aerosol generator or heater 192 is arranged to cause aerosol to be generated from a different portion of the aerosol generating article. For example, a plurality of discrete portions of aerosol generating material may be provided on the substrate 110 and each discrete portion of aerosol generating material may be heated separately by a separate aerosol generator or heater 192.

The aerosol provision device 100 may comprise one or more chambers 190 in which one or more warming elements 200 are located. According to an embodiment a plurality of chambers 190 may be provided above a common reception region 225 which is arranged to receive an aerosol generating article. Some or each of the chambers 190 may have a warming element 190 disposed therein.

The or each warming element 200 may comprise ferritic material which may be heated to a temperature of e.g. 60-150 °C during a session of use. According to an embodiment the or each aerosol generator or heater 192 may be arranged to warm a warming element 200 to a temperature in the range 60-70 °C, 70-80 °C, 80-90 °C, 90- 100°C, 100-110°C, 110-120 °C, 120-130 °C, 130-140 °C or 140-150 °C during a session of use. The warming element(s) 200 comprising ferritic material may be warmed by interacting with a time varying magnetic field which may be generated by an aerosol generator or heater 192 which may comprise one or more inductor coils.

In alternative embodiments the one or more warming elements 200 may be heated by a warming unit (not shown) which may comprise either one or more resistive heaters and/or one or more (further) inductive heaters. Accordingly, it is contemplated that the one or more warming elements 200 may be heated by a resistive or inductive heater other than the aerosol generator or heater 192 located adjacent the reception region 192. The warming element 200 may be relatively thin and may have a thickness < 25 pm. For example, the ferritic material which forms the warming element 200 may have a thickness < 25 pm, < 20 pm, < 15 pm or < 10 pm.

The aerosol generator or heater 192 may comprise an inductive heater 192 which enables rapid heating of aerosol generating material provided on the substrate 110 to be achieved but such rapid heating may increase the risk of condensate forming since inductive heaters may generate condensate-forming substances at a greater rate than they can be carried away in a flow of aerosol. Accordingly, the provision of one or more warming elements 200 (which may be located in the region in which aerosol is initially released into) can substantially prevent the formation of condensation within the chamber 190. The aerosol provision device 100 has a reception region 225 into which an aerosol generating article comprising aerosol generating material is introduced. The aerosol generating article may comprise a planar aerosol generating article comprising aerosol generating material. However, it will be understood that the aerosol generating article may have a geometry other than planar. According to various embodiments an aerosol generator or heater 192 is located adjacent the reception region 225 and is arranged to cause aerosol to be generated from the aerosol generating material which is provided on the substrate 110 or which may comprise the substrate 110. In particular, it will be appreciated that the formation of condensation on the upper internal surface of the chamber 190 (i.e. on the opposite side to that defined by aerosol generator or heater 192) would be particularly problematic.

The reception region 225 is located between the aerosol generator or heater 192 and the one or more warming elements 200. That is, the aerosol generator or heater 192 is located on or adjacent to one side of the reception region 225, whereas the one or more warming elements 200 are located on or adjacent to another side of the reception region 225, such that at no point is the aerosol generator or heater 192 closer to the one or more warming elements 200 than to the reception region 225.

As discussed above, according to an embodiment the aerosol generator or heater 192 may comprise one or more first inductors. The one or more first inductors are also arranged to warm the warming element 200 in order to reduce the formation of condensation within the chamber 190.

The substrate 110 may include a metallic element (i.e. a susceptor) that is arranged to be heated by a varying magnetic field produced by one or more first inductors which may comprise the aerosol generator or heater 192. The susceptor may comprise a metallic foil and in particular the susceptor may comprise aluminium foil.

It will be understood that aluminium foil has a relatively low magnetic permeability and hence some magnetic flux (generated by the one or more first inductors) will pass through and beyond the susceptor which is provided on the substrate 110. The one or more warming elements 200 which are positioned on the other side of the reception region 225 to that of the one or more inductors which form the aerosol generator or heater 192 may therefore be arranged to interact with the varying magnetic flux which has not been fully absorbed by the susceptor of the substrate 110. As a result, the one or more warming elements 200 which comprise ferritic material may become warmed through inductive heating. Such inductive heating may be viewed as a way in which the warming element 200 may be heated during a session of use.

In embodiments wherein the warming element 200 comprises ferritic material (e.g. ferromagnetic and/or ferromagnetic material), inductive heating of the warming element 200 will be additionally enhanced as a result of magnetic hysteresis losses. Accordingly, the warming element 200 may be more susceptible to inductive heating by a varying magnetic field than the susceptor of the substrate 110. However, due to the relative positioning of the susceptor, in use, between the one or more inductors which comprise the aerosol generator or heater 192 and the warming element 200, a relatively low level of magnetic flux may reach and penetrate the warming element 200. However, since the warming element 200 may comprise ferritic material then the ferritic material may have a relatively high sensitivity to being inductively heated which permits the warming element 200 to be warmed even at relatively low values of magnetic flux.

The ferritic material which may comprise the one or more warming elements 200 may have a magnetic permeability pi and the susceptor (e.g. aluminium foil) provided as part of the aerosol generating article or consumable may have a magnetic permeability 2. Embodiments are contemplated wherein the ratio p p2 is < 100, 100-500, 500-1000, 1000-1500, 1500-2000, 2000-2500, 2500-3000, 3000-3500, 3500-4000, 4000-4500, 4500-5000 or > 5000 i.e. the ferritic material provided as part of the one or more warming elements 200 may have a magnetic permeability which is substantially higher than that of the susceptor (e.g. aluminium foil). According to various embodiments the ferritic material may have a relative magnetic permeability selected from the range: (i) 100-200 p/ o; (ii) 200-300 p/po; (iii) 300-400 p/po; (iv) 400-500 p/po; (v) 500-600 p/po; (vi) 600-700 p/po; (vii) 700-800 p/po; (viii) 800-900 p/po; (ix) 900-1000 p/po; (x) 1000-1100 p/po; (xi) 1100-1200 p/p ₀ ; (xii) 1200-1300 p/p ₀ ; (xiii) 1300-1400 p/p ₀ ; (xiv) 1400-1500 p/p ₀ ; (xv) 1500-1600 p/po; (xvi) 1600-1700 p/po; (xvii) 1700-1800 p/po; (xviii) 1800-1900 p/po; (xix) 1900-2000 p/po; (xx) > 2000 p/po. According to various embodiments the aerosol generator or heater 192 may comprise one or more induction coils having a first surface area Ai in a plane parallel with a planar surface of the susceptor and wherein the warming element 200 has a second surface area A2 in a plane parallel with the planar surface of the susceptor, wherein the ratio A2/A1 is in the range: (i) 0.7-0.8; (ii) 0.8-0.9; (iii) 0.9-1.0; (iv) 1.0-1.1 ; (v) 1.1-1.2; and (vi) 1.2-1.3.

The aerosol generator or heater 192 may be arranged to heat the susceptor and/or the aerosol generating material to a temperature in the range 200-400 °C during a session of use. According to various embodiments the aerosol generator or heater 192 may be arranged to heat the susceptor to a temperature in the range 200-220 °C, 220- 240 °C, 240-260 °C, 260-280 °C, 280-300 °C, 300-320 °C, 320-340 °C, 340-360 °C, 360- 380 °C or 380-400 °C during a session of use. According to various embodiments the aerosol generator or heater 192 is arranged to heat the aerosol generating material to a temperature in the range 200-220 °C, 220-240 °C, 240-260 °C, 260-280 °C, 280-300 °C, 300-320 °C, 320-340 °C, 340-360 °C, 360-380 °C or 380-400 °C during a session of use.

It is not essential that the warming element 200 is heated by inductive heating by the aerosol generator or heater 192 which may be located in close proximity to the reception region 225. For example, according to alternative embodiments, the aerosol generator or heater 192 may comprise one or more first resistive heaters in which case the warming element 200 may be heated by other means.

It is envisaged that the warming element 200, in some embodiments in combination with heat transfer via conduction or radiation from the aerosol generator or heater 192, will heat air within the reception region 225. This heating of air within the reception region 225 helps to substantially prevent the accumulation of condensation within the reception region 225. In particular examples, the air in the vicinity of the aerosol generating article comprising substrate 110 may be heated to a temperature of greater than or equal to 120°C. This may be sufficient to substantially reduce the likelihood that condensate forms within the chamber 190. In other embodiments the warming element 200 may be warmed to a lower or higher temperature such that the air in the vicinity of the aerosol generating article may be heated to a temperature greater than or equal to 150°C, or, in still other cases, greater than or equal to 170°C, or, in yet further cases, greater than or equal to 200°C.

Other approaches to heating or warming the warming element 200 during a session of use are contemplated. For instance, in an embodiment, instead of the warming element 200 being warmed by the first inductors, the warming element 200 may instead be warmed by a separate warming unit (not shown). The warming unit is arranged to warm the warming element 200 in order to reduce the formation of condensation within the chamber 190. The warming unit 200 may comprise either one or more inductors or one or more resistive heaters. The ferritic material may comprise a coating or foil and the ferritic material may have a thickness < 25 pm.

The warming element 200 may be arranged to be planar and may comprise a planar inner surface of the chamber 190. Other embodiments are contemplated wherein the warming element 200 may be curved, concave, convex or dome shaped. For example, the warming element 200 may comprise a curved, concave, convex or dome shaped inner surface of the chamber 190. In the particular example shown in Fig. 9 a single chamber 190 is shown. However, other embodiments are contemplated wherein the aerosol provision device 100 may comprise a plurality of discrete chambers. For example, at least some or each chamber may be arranged in order to receive aerosol generated from a different portion of the aerosol generating article. At least some or each of the chambers 190 may comprise a warming element 200 comprising ferritic material wherein each warming element 200 may be provided in order to prevent the formation of condensation within each of the chambers 190.

According to various embodiments the aerosol provision device 100 may be arranged to move, translate or rotate the aerosol generating article relative to the at least one aerosol generator or heater 192 during a session of use. An aerosol generating system is also disclosed comprising an aerosol provision device 100 in combination with a substrate 110 or aerosol generating article comprising aerosol generating material and a susceptor. The susceptor may comprise a metallic foil such as aluminium foil and the susceptor may have a relative magnetic permeability 1.0 p/ o. The susceptor may be relatively thin and may have a thickness < 10 pm.

Other embodiments are contemplated wherein the susceptor may comprise a material other than aluminium. In particular, the susceptor may comprise a material which has a higher relative magnetic permeability than that of aluminium. For example, according to various embodiments the susceptor may have a relative magnetic permeability selected from: (i) < 100 p/po; (ii) 100-200 p/po; (iii) 200-300 p/po; (iv) 300- 400 p/po; (v) 400-500 p/po; (vi) 500-600 p/po; (vii) 600-700 p/po; (viii) 700-800 p/po; (ix) 800-900 p/p ₀ ; (x) 900-1000 p/p ₀ ; (xi) 1000-1100 p/p ₀ ; (xii) 1100-1200 p/p ₀ ; (xiii) 1200- 1300 p/po; (xiv) 1300-1400 p/po; (xv) 1400-1500 p/po; (xvi) 1500-1600 p/po; (xvii) 1600- 1700 p/po; (xviii) 1700-1800 p/po; (xix) 1800-1900 p/po; (xx) 1900-2000 p/po; and (xxi) > 2000 p/po.

The warming element 200 and the susceptor which forms part of the aerosol generating article may be arranged to be located relatively close to each other. For example, at least a portion of the warming element 200 may be spaced < 4 mm apart from an upper surface of the susceptor. The warming element 200 comprising ferritic material also enables the chamber 190 to have a relatively large volume whilst still allowing the warming element 200 to be warmed sufficiently so as to reduce the formation of condensates within the chamber 190.

According to various embodiments, the one or more warming elements may comprise ferritic material which may comprise type 430 stainless steel. Type 430 stainless steel is particularly beneficial in that type 430 stainless steel exhibits a relatively high level of corrosion resistance whilst at the same time is formable and is relatively ductile enabling a warming element 200 having a desired shape or profile to be manufactured or fabricated at relatively low cost.

According to various embodiments the ferritic material may comprise non- hardenable plain chromium stainless steel which possesses excellent finish quality. Type 430 or grade 430 stainless steel also has excellent resistance to nitric attack which makes it particularly well suited to use in chemical applications. According to various embodiments the ferritic material, such as type 430 stainless steel or other forms of stainless steel, may be utilised which have a relative permeability p _r in the range 100- 1800 p/po.

More generally the ferritic material may comprise steel (i.e. an alloy) which may include chromium and optionally other trace elements. The ferritic material may have a relative magnetic permeability _r which may be determined from the variation of B/H from a hysteresis curve wherein B is the magnetic flux density and H is the magnetic field strength. The ferritic material may have a relative permeability _r = p/po wherein po = 4TT x 10’ ⁷ H/m.

A method of generating aerosol is also disclosed comprising providing an aerosol provision device and introducing a substrate or aerosol generating article comprising aerosol generating material and a susceptor into the aerosol provision device.

Fig. 10 shows an image of a substrate 110 and an associated warming element 200 according to an embodiment wherein the warming element 200 is provided in the upper region of a chamber 190 having a reception region 225. The warming element 200 comprises ferritic material and is intended to reduce the risk of condensate collecting within the chamber 190. In particular, it is desired to avoid there being any unheated portions of an aerosol flow path through the aerosol provision device. In particular, if aerosol were to encounter a region of lower temperature then the aerosol may experience a pressure drop as it flows through the region. In such circumstances condensate might tend, owing to the pressure differential, to move towards the cooler regions. The warming element 200 according to various embodiments substantially prevents this from occurring.

According to various embodiments at least part of the interior surface of the chamber 190 may effectively be warmed or heated during a session of use via one or more warming elements 200 so that any accumulation of condensate within the chamber 190 may be limited or substantially prevented. The heating or warming of the warming element 200 located within the chamber 190 encourages any condensate which may be forming to re-evaporate thereby assisting the exit of condensate-forming substances from the chamber 190. Additionally or alternatively, such heating of the interior surface of the chamber 190 may cause the air within the chamber 190 to be warmed or heated, thereby increasing the amount of moisture retained by the air and thus reducing the likelihood that condensate forms in chamber 190. As will be understood, the warming element 200 may form part of the interior surface of the chamber 190 itself or may comprise a separate element.

The warming or heating of the interior surface of the chamber 190 may result in at least a portion of the interior surface of the chamber 190 attaining a temperature greater than or equal to 85°C which is sufficient to cause significant re-evaporation of condensate or to prevent condensate from forming in the first instance. According to other embodiments the aerosol provision device may be configured to attain a temperature of at least 90°C for at least a portion of the interior surface, in other cases at least 95°C, in still other cases at least 100°C. As may be appreciated, this may encourage condensate to re-evaporate, assisting the exit of condensate-forming substances from the inlet conduit.

As mentioned above, heating of the interior surface of chamber 190 may cause the air within the region in question to be heated, thereby increasing the amount of moisture retained by the air and thus reducing the likelihood that condensate forms in the conduit in question. Accordingly, heating of the interior surface of the chamber 190 may cause the air within the conduit in question to be heated to a temperature greater than or equal to 120°C which will, in many cases, be sufficient to materially reduce the likelihood that condensate forms in the region in question. In other cases, it may be appropriate to configure the aerosol provision device such that the air is heated to a temperature of greater than or equal to 150°C, or, in still other cases, greater than or equal to 170°C, or, in yet further cases, greater than or equal to 200°C.

Fig. 11 shows experimental results which were obtained by heating a warming element 200 which comprised a ferritic plate together with a substrate 110 similar to those shown in Fig. 10. The experimental results shown in Fig. 11 show how the temperature of the warming element 200 (bottom trace) and the temperature of the aluminium foil susceptor (upper trace) which was provided on the substrate 110 varied as a function of time. The aluminium foil susceptor was 6.5 pm thick and was provided on the substrate 110 (which comprised 104 pm thick paper/card). Aerosol generating material was located upon the aluminium foil susceptor. The warming element 200 was positioned 1.8 mm from the upper surface of the aluminium foil susceptor.

The inductor coil which was used to heat or warm both the aluminium foil susceptor and the warming element 200 comprised a LITZ (RTM) coil. The lower trace shows how the temperature profile of the warming element 200 peaked at around 130 °C after approximately 10s after the inductor coil was first energised. The upper trace shows how the temperature profile of the aluminium foil susceptor varied as a function of time. The aerosol provision device was operated with a desired set-point or target operating temperature of 300 °C being set for the aluminium foil susceptor. However, the presence of the warming element 200 in close proximity to the aluminium foil susceptor had the effect of reducing the set point slightly such that the maximum temperature of the aluminium foil susceptor peaked at around 280 °C after approximately 10s after the inductor coil was energised.

While the above described embodiments have in some respects focused on some specific example aerosol generating systems, it will be appreciated the same principles can be applied for aerosol generating systems using other technologies. That is to say, the specific manner in which various aspects of the aerosol provision system function are not directly relevant to the principles underlying the examples described herein. The aerosol provision system may be used in a tobacco industry product, for example a non-combustible aerosol provision system. The tobacco industry product may comprise a heating product which releases one or more compounds by heating, but not burning, a substrate material. The substrate material may comprise an aerosolisable material which may be for example tobacco or other non-tobacco products, which may or may not contain nicotine. The heating device product may comprise a tobacco heating product. The heating product may comprise an electronic device or a non-electronic article. The tobacco industry product may comprise a hybrid system to generate aerosol by heating, but not burning, a combination of substrate materials. The substrate materials may, for example, comprise a solid, liquid or gel which may or may not contain nicotine. In one embodiment, the hybrid system may comprise a liquid or gel substrate in combination with a solid substrate. The solid substrate may comprise a tobacco or nontobacco product, which may or may not contain nicotine. In one embodiment, the hybrid system may comprise a liquid or gel substrate in combination with a tobacco rod or substrate.

In order to address various issues and advance the art, this disclosure shows by way of illustration various embodiments. The advantages and features of the disclosure are of a representative sample of embodiments only, and are not exhaustive and/or exclusive. They are presented only to assist in understanding and to teach the claimed invention(s). It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects of the disclosure are not to be considered limitations on the disclosure as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and modifications may be made without departing from the scope of the claims. Various embodiments may suitably comprise, consist of, or consist essentially of, various combinations of the disclosed elements, components, features, parts, steps, means, etc. other than those specifically described herein, and it will thus be appreciated that features of the dependent claims may be combined with features of the independent claims in combinations other than those explicitly set out in the claims. The disclosure may include other inventions not presently claimed, but which may be claimed in future.