EA041326B1 - AEROSOL GENERATING DEVICE AND HEATING CHAMBER FOR IT - Google Patents

Description

Technical field

The invention relates to an aerosol generating device and to insulation of a heating chamber for it. The present invention is particularly applicable to a portable evaporator which can be autonomous and low temperature. Such devices may heat rather than burn tobacco or other suitable materials by conduction, convection and/or radiation to generate inhalation vapor.

Prerequisites for the creation of the invention

The popularity and use of reduced-risk or modified-risk devices (also known as vaporizers) has grown rapidly in the past few years as an aid to helping seasoned smokers wish to quit traditional tobacco products such as cigarettes, cigars, cigarillos, and roll-your-own tobacco. Various devices and systems are available that heat or heat aerosol-forming substances, as opposed to the combustion of tobacco in conventional tobacco products.

A publicly available reduced risk or modified risk device is a heated device that generates an aerosol from a substrate or a non-burning heating device. Devices of this type generate an aerosol or vapor by heating an aerosol-generating substrate, typically containing moistened tobacco leaf or other suitable aerosol-forming material, to a temperature typically in the range of 150 to 300°C. When the aerosol-forming substrate is heated, but not combusted or combusted, an aerosol is released containing components desired by the user, but non-toxic and carcinogenic by-products of combustion and combustion. In addition, an aerosol obtained by heating tobacco or other aerosol-forming material does not generally produce a burnt or bitter taste due to combustion or burning that may be unpleasant to the user, and therefore sugars and other additives are not required for the substrate, which are usually added to such materials in order to make the taste of smoke and/or steam more attractive to the user.

In general terms, it is required to quickly heat the aerosol-forming substrate to a temperature at which the aerosol can be released from it and maintain the aerosol-forming substrate at that temperature. It will be appreciated that the aerosol will be released from the aerosol-forming substrate and delivered to the user only when the air flow passes through the aerosol-forming substrate.

An aerosol generating device of this type is a portable device, so power consumption is an important design factor. The present invention is directed to solving the problems of existing devices and to provide an improved aerosol generating device and heating chamber therefor.

The essence of the invention

The aim of the present invention is to provide a heating chamber having efficient heating and heat insulating properties while preventing heat concentration, i.e. the formation of hot spots at the bottom of the chamber, which would affect the quality of the generated aerosol. This object is achieved by using a heating chamber for an aerosol generating device, which is described in independent claim 1 of the claims, and an aerosol generating device containing such a chamber and described in independent claim 12 of the claims.

According to a first aspect of the present invention, there is provided a heating chamber for an aerosol generating device, the heating chamber comprising a side wall of the chamber; the base of the chamber, and the side wall of the chamber and the base of the chamber together form the internal volume of the heating chamber; a heater attached to the outer surface of the heating chamber and in thermal contact with the side wall of the chamber; and a heat insulating element comprising an insulating side wall and an insulating base, wherein the heat insulating element is designed in such a way that the part of the heating chamber containing the base of the chamber is inserted inside the heat insulating element, while the heater passes around the side wall of the chamber, but does not pass around the base of the chamber, which away from the insulating base.

Optionally, the insulating side wall has a lower thermal conductivity than the insulating base.

Optionally, the chamber base is in thermally conductive engagement with the insulating base.

Optionally, the heat insulating element is in the form of a sleeve with a hollow interior and an open top.

Optionally, the insulating side wall comprises an insulating side wall chamber containing gas at a pressure below atmospheric pressure.

Optionally, the insulating side wall chamber contains a vacuum.

Optionally, the insulating side wall is less than 1 mm thick and preferably about 0.3 mm thick.

- 1 041326

Optionally, the insulating base comprises an insulating base chamber containing a gas at a pressure below atmospheric pressure.

Optionally, the chamber of the insulating base contains a vacuum.

Optionally, the insulating base has a thickness of less than 1 mm and preferably 0.3 mm.

Optionally, the insulating base is a flexible element that provides a through passage for electrical connectors.

Optionally, the flexible element is made of silicone.

Optionally, the insulating base and the insulating side wall form one sleeve-shaped cavity.

Optionally, the heater includes electrical connections for receiving power, and the electrical connections pass through the insulating base.

Optionally, the heater includes electrical connections for receiving power, and the electrical connections extend around the top of the insulating sidewall.

Optionally, the inner surface of the insulating side wall is treated to reduce emissivity.

Optionally, the heat insulating element comprises one or more of the following: cotton; airgel; foam; fibrous material; and fiberglass.

According to a second aspect of the present invention, an aerosol generating device is provided, comprising: a power supply; outer shell; a heating chamber as described above, located inside the outer shell; and a control circuit configured to control the supply of power from the power source to the heater.

Optionally, the aerosol generating device further comprises a resiliently deformable member between the outwardly facing surface of the insulating side wall and the outer shell to hold the thermal insulating member in place.

Optionally, the heat insulating element is supported by spacers extending between the heat insulating element and the outer shell.

Optionally, the heating chamber is secured in the aerosol generating device by engagement portions on the outer shell to engage with the side wall of the chamber at the open end of the heating chamber.

Optionally, the heating chamber is removable from the aerosol generating device.

By not having any part of the heater at the bottom of the chamber and by providing a distance between the bottom of the chamber and the insulating base in this area, a more uniform distribution of heat to the heating chamber is achieved, since the insulating gap formed at the bottom of the chamber compensates for the absence of a heater in this area.

Brief description of graphic materials

In FIG. 1 is a schematic perspective view of an aerosol generating device according to the first embodiment of the present invention.

In FIG. 2 is a schematic side sectional view of the aerosol generating device of FIG. 1.

In FIG. 2(a) is a schematic top sectional view of the aerosol generating device of FIG. 1 along the line X-X shown in FIG. 2.

In FIG. 3 is a schematic perspective view of the aerosol generating device of FIG. 1 shown with an aerosol generating substrate holder loaded into an aerosol generating device.

In FIG. 4 is a schematic side sectional view of the aerosol generating device of FIG. 1 shown with an aerosol generating substrate holder loaded into an aerosol generating device.

In FIG. 5 is a schematic perspective view of the aerosol generating device of FIG. 1 shown with an aerosol generating substrate holder loaded into an aerosol generating device.

In FIG. 6 is a schematic side sectional view of the aerosol generating device of FIG. 1 shown with an aerosol generating substrate holder loaded into an aerosol generating device.

In FIG. 6(a) is a detailed sectional view of a portion of FIG. 6, which highlights the interaction between the substrate holder and the protrusions in the heating chamber and the corresponding effect on the air flow paths.

In FIG. 7 is a plan view of the heater separated from the heating chamber.

In FIG. 8 is a schematic side sectional view of an aerosol generating device according to a second embodiment of the present invention having an alternative airflow configuration.

In FIG. 9 shows the side wall of the chamber with the base of the chamber, forming a heating chamber, surrounded by an insulating side wall and an insulating base, forming a heat-insulating element of a one-piece structure.

In FIG. 10 shows a chamber side wall with a chamber base forming a heating chamber surrounded by an insulating side wall and an insulating base forming a heat insulating element, the insulating side wall and the insulating base being separate elements.

In FIG. 11 shows a side wall of a chamber with a chamber base forming a heating chamber surrounded by an insulating side wall and an insulating base forming a heat insulating element, the heating chamber being in thermally conductive engagement with the insulating base.

In FIG. 12 shows a chamber side wall with a chamber base forming a heating chamber surrounded by an insulating side wall and an insulating base forming a heat insulating element, with the heating chamber on top of the insulating base.

In FIG. 13 shows a side wall of a chamber with a chamber base forming a heating chamber surrounded by an insulating side wall and an insulating base forming a heat insulating member, the insulating base being flexible to allow heater tracks to fit around the insulating base.

In FIG. 14 shows a chamber side wall with a chamber base forming a heating chamber surrounded by an insulating side wall and an insulating base forming a heat insulating element, the insulating base containing a space through which the electrical connections of the heating elements pass.

In FIG. 15 shows a chamber side wall with a chamber base forming a heating chamber surrounded by an insulating side wall and an insulating base forming a heat insulating element, the heating chamber comprising a heater with electrical connections and the electrical connections extending around the top of the heat insulating element.

Detailed description of embodiments

First embodiment.

With reference to FIG. 1 and 2, according to the first embodiment of the present invention, the aerosol generating device 100 includes an outer shell 102 housing various components of the aerosol generating device 100. In the first embodiment, the outer shell 102 is tubular. More specifically, it is cylindrical. It should be noted that the outer shell 102 need not be tubular or cylindrical, but may be any shape, as long as its size will accommodate the components described in the various embodiments set forth herein. The outer shell 102 may be formed from any suitable material or, moreover, from layers of material. For example, an inner layer of metal may be surrounded by an outer layer of plastic. This provides a pleasant feeling to the user when holding the outer shell 102. Any heat leakage from the aerosol generating device 100 is distributed around the circumference of the outer shell 102 by the metal layer, thus preventing hot spots from forming, while the plastic layer softens the outer shell 102 to the touch. In addition, the plastic layer can help protect the metal layer from oxidation or scratches, which improves the appearance of the aerosol generating device 100 in the long term.

The first end 104 of the aerosol generating device 100, shown towards the bottom of each of FIGS. 1-6 is described for convenience as the bottom, base, or lower end of the aerosol generating device 100. The second end 106 of the aerosol generating device 100, shown towards the top of each of FIGS. 1-6 is described as the top or top end of the aerosol generating device 100. In a first embodiment, the first end 104 is the lower end of the outer shell 102. In use, the user typically orients the aerosol generating device 100 with the first end 104 down and/or distal to the user's mouth and the second end 106 up and/or proximal. position relative to the user's mouth.

As shown, the aerosol generating device 100 holds the pair of washers 107a, 107b in place at the second end 106 by an interference fit with the inside of the outer shell 102 (only the top washer 107a is visible in FIGS. 1, 3 and 5). In some embodiments, the outer shell 102 is folded or bent around the top of the washers 107a at the second end 106 of the aerosol generating device 100 to hold the washers 107a, 107b in place. The second of the washers 107b (i.e., the washer furthest from the second end 106 of the aerosol generating device 100) rests on the shoulder or annular ridge 109 of the outer shell 102, thereby preventing the bottom washer 107b from landing more than a predetermined distance from the second end 106 of the aerosol generating device 100. Washers 107a, 107b are formed from heat insulating material. In this embodiment, the thermal insulating material is suitable for use in medical devices, such as polyether ether ketone (PEEK).

- 3 041326

The aerosol generating device 100 has a heating chamber 108 disposed towards the second end 106 of the aerosol generating device 100. The heating chamber 108 is open towards the second end 106 of the aerosol generating device 100. The aerosol generating device 108 has a first open end 110 towards a second end 106 of the aerosol generating device 100. The heating chamber 108 is kept at a distance from the inner surface of the outer shell 102 by seating washers 107a, 107b through the central hole. With this arrangement, the heating chamber 108 is held broadly coaxial with the outer shell 102. The heating chamber 108 is suspended by a flange 138 of the heating chamber 108 located at the open end 110 of the heating chamber 108 and held between a pair of washers 107a, 107b. This means that the conduction of heat from the heating chamber 108 to the outer shell 102 usually passes through the washers 107a, 107b and is thus limited by the heat insulating properties of the washers 107a, 107b. Because there is an air gap otherwise surrounding the heating chamber 108, heat transfer from the heating chamber 108 to the outer shell 102 other than through the washers 107a, 107b is also reduced. In the depicted embodiment, the flange 138 extends outwardly from the side wall 126 of the heating chamber 108 for a distance of approximately 1 mm, forming an annular structure.

To further increase the thermal insulation of the heating chamber 108, the heating chamber 108 is also surrounded by insulation. In some embodiments, the insulation is a fibrous material or foam such as cotton wool. In the depicted embodiment, the insulation comprises a thermal element 152 in the form of an insulating sleeve comprising a double wall tube 154 and a base 156. In some embodiments, the thermal element 152 may comprise a pair of nested sleeves enclosing a cavity therebetween. The cavity 158 formed between the walls of the double wall tube 154 may be filled with a heat insulating material, such as fibers, foams, gels, or gases (eg, under low pressure). In some cases, the cavity 158 may contain a vacuum. Advantageously, the vacuum requires very little thickness to achieve high thermal insulation, and the walls of the double wall tube 154 enclosing the cavity 158 can be up to 100 microns thick, and the total thickness (of the two walls and the cavity 158 between them) can be up to 1 mm. Base 156 is an insulating material such as silicone. Because silicone is malleable, electrical connections 150 for heater 124 can pass through base 156 forming a seal around electrical connections 150.

As shown in FIG. 1-6, the aerosol generating device 100 may include an outer shell 102, a heating chamber 108, and a heat insulating member 152, as described in detail above. In FIG. 1-6 show a resiliently deformable member 160 positioned between the outwardly facing surface of the insulating sidewall 154 and the inner surface of the outer shell 102 to hold the thermally insulating member 152 in place. The elastically deformable element 160 may provide sufficient friction to provide an interference fit to hold the thermally insulating element 152 in place. and the inner surface of the outer shell 102. The elastically deformable element 160 may be formed from a thermally insulating material such as silicone. This may provide additional insulation between the heat insulating element 152 and the outer shell 102. Thus, heat transfer to the outer shell 102 can be reduced so that the user can comfortably hold the outer shell 102 during use. back to its previous form, and is, for example, elastic or rubber materials.

As an alternative to this arrangement, the thermal element 152 may be supported by struts extending between the thermal element 152 and the outer shell 102. The struts provide increased rigidity so that the heating chamber 108 is located centrally in the outer shell 102, or so that it is located in given location. This can be calculated so that the heat is evenly distributed throughout the outer shell 102 in order to avoid the development of hot spots.

As another alternative, the heating chamber 108 may be secured in the aerosol generating device 100 by means of engagement portions on the outer shell 102 to engage with the side wall 126 at the open end 110 of the heating chamber 108. Since the open end 110 is exposed to the highest flow cold air and therefore cools the fastest, attaching a heating chamber 108 to the outer shell 102 near the open end 110 can allow for rapid heat dissipation to the environment and a secure fit.

It should be noted that in some embodiments, the heating chamber 108 is removable from the aerosol generating device 100. Thus, the heating chamber 108 can be easily cleaned or replaced. In such embodiments, heater 124 and electrical connections 150 may be non-removable and may remain in place in thermal element 152.

In the first embodiment, the base 112 of the heating chamber 108 is closed. Those. the heating chamber 108 is in the form of a sleeve. In other embodiments, the base 112 of the heating chamber 108 has one or more holes or is perforated, while the heating chamber 108 remains generally in the form of a sleeve, but is not closed on the base 112. In other embodiments, the base 112 is closed, but the side wall 126 has one or more holes or is perforated in a region adjacent to base 112, such as between heater 124 (or metal layer 144) and casing 112. Heating chamber 108 also has a side wall 126 between base 112 and open end 110. Side wall 126 and the base 112 are connected to each other. In the first embodiment, the side wall 126 is tubular. More specifically, it is cylindrical. However, in other embodiments, the side wall 126 has other suitable shapes, such as a tube shape with an elliptical or polygonal cross section. Typically, the cross section is uniform along the length of the heating chamber 108 (not including the protrusions 140), however, in other embodiments, it may vary, for example, the cross section may decrease in size towards one end so that the tubular shape tapers or is truncated-conical.

In the depicted embodiment, the heating chamber 108 is integral, i. side wall 126 and base 112 are formed from a single piece of material, such as by a deep drawing process. This may result in an overall stronger heating chamber 108. Other examples may have the base 112 and/or the flange 138 formed as a separate piece and then attached to the side wall 126. This in turn allows the formation of the flange 138 and/or or a base 112 of a material different from that of the side wall 126. The side wall 126 itself is thin walled. In some embodiments, the implementation of the side wall has a thickness of up to 150 microns. Typically, sidewall 126 has a thickness of less than 100 microns, such as about 90 microns or even about 80 microns. In other cases, it is possible for the side wall 126 to have a thickness of approximately 50 microns, although as the thickness decreases, the frequency of failures during the manufacturing process increases. In general, the range from 50 to 100 µm is usually suitable, with the range from 70 to 90 µm being optimal. Technological tolerances are approximately ±10 µm, however, the parameters presented are expected to be accurate to approximately ±5 µm.

If the side wall 126 is as thin as described above, the thermal properties of the heating chamber 108 change markedly. parallel to the central axis or around the circumference of the side wall 126) has a small channel along which conduction can occur, and thus the heat generated by the heater 124 located on the outer surface of the heating chamber 108 remains localized near the heater 124 in the direction radially outward from the side wall 126 at the open end, but quickly leads to heating of the inner surface of the heating chamber 108. In addition, the thin side wall 126 helps to reduce the heat capacity of the heating chamber 108, which in turn improves the overall efficiency of the aerosol generating device 100, since less energy is uses when heating the side wall 126.

The heating chamber 108, and in particular the side wall 126 of the heating chamber 108, contains a material having a thermal conductivity of 50 W/mK or less. In the first embodiment, the heating chamber 108 is metal, preferably stainless steel. Stainless steel has a thermal conductivity of about 15 to 40 W/mK, with the exact value depending on the specific alloy. As a further example, 300 grade stainless steel, which is suitable for this application, has a thermal conductivity of approximately 16 W/mK. Suitable examples include stainless steel grades 304, 316, and 321, which have been approved for medical use, are strong, and have low enough thermal conductivity to allow for the heat localization described herein.

Materials with thermal conductivity at the described levels reduce the ability to conduct heat away from the area to which heat is applied, compared with materials with higher thermal conductivity. For example, heat remains localized near the heater 124. Since the transfer of heat to other parts of the aerosol generating device 100 is suppressed, the heating efficiency is thus increased by ensuring that only those parts of the aerosol generating device 100 that are intended to actually heat up. for heating, and those that are not intended are not heated.

Metals are suitable materials because they are strong, malleable and easy to shape and form. In addition, their thermal properties vary widely from

- 5 041326 metal to metal, and if necessary, they can be adjusted by careful selection of the composition of the alloy. In this application, the term metal refers to elemental (ie, pure) metals, as well as alloys of several metals or other elements, such as carbon.

Accordingly, the configuration of the heating chamber 108 with thin side walls 126, together with the choice of materials with the desired thermal properties from which the side walls 126 are formed, allows heat to be efficiently conducted through the side walls 126 and into the aerosol forming substrate 128. Advantageously, this also results in a reduction in the time required for the temperature to rise from ambient temperature to a temperature at which aerosol can be released from the aerosol forming substrate 128 after initial actuation of the heater.

The heating chamber 108 is formed by deep drawing. It is an efficient way of forming the heating chamber 108 and can be used to provide a very thin side wall 126. The deep drawing process involves pressing a sheet metal blank with a punch to press it into a mold of a particular shape. By using a series of progressively smaller punches and dies, a tubular structure is formed having a base at one end and a tube whose depth is greater than the distance across the tube (i.e. the tube is relatively longer than wide, giving rise to the term deep drawing). Due to the formation by this method, the side wall of the tube thus formed has the same thickness as the original sheet metal. Similarly, the base thus formed has the same thickness as the original sheet metal blank. The flange may be formed at the end of the tube by leaving the rim of the original sheet metal blank to extend outward at the opposite end of the tubular wall (i.e., starting with more material in the blank than is required to form the tube and base).

Alternatively, the flange may be subsequently formed in a separate step including one or more of cutting, bending, rolling, crimping, etc.

As described, the tubular side wall 126 according to the first embodiment is thinner than the base 112. This can be achieved by first deep drawing the tubular side wall 126 and then thinning the wall. The term thinning draw refers to heating the tubular sidewall 126 and drawing it so that it thins during the process. Thus, the tubular side wall 126 can be made to the dimensions described herein.

The thin sidewall 126 may be brittle. The effects of this can be reduced by providing additional structural support for the side wall 126 and by forming the side wall 126 in a tubular, and preferably cylindrical, shape. In some instances, additional structural support is provided as an optional feature, however, it should be noted that flange 138 and base 112 also provide some degree of structural support. more prone to collapse, while providing the heating chamber 108 according to the present invention with a base 112 adds support. It should be noted that in the depicted embodiment, base 112 is thicker than side wall 126, such as 2 to 10 times thicker than side wall 126. In some cases, this may result in base 112 having a thickness of 200 to 500 µm, for example a thickness of 400 µm. The base 112 also has the additional purpose of preventing the substrate holder 114 from being pushed too far into the aerosol generating device 100. The increased thickness of the base 112 helps prevent damage to the heating chamber 108 if the user inadvertently applies too much force when inserting the cartridge holder 114. Similarly, when cleaning the heating chamber 108 by a user, the user can typically introduce an object, such as an elongated brush, through the open end 110 of the heating chamber 108. This means that the user is more likely to apply more force to the base 112 of the heating chamber 108 because the elongated object abuts against the base 112 rather than the side wall 126. Therefore, the thickness of the base 112 relative to the side wall 126 can help prevent damage to the heating chamber 108 in during cleaning. In other embodiments, the base 112 has the same thickness as the side wall 126, which provides some of the above benefits.

Flange 138 extends outward from side wall 126 and has an annular shape extending around the entire circumference of the rim of side wall 126 at open end 110 of heating chamber 108. Flange 138 resists bending and shear forces against side wall 126. For example, lateral deformation of a tube formed by side wall wall 126 would likely require flange 138 to bulge. It should be noted that while flange 138 is shown to extend broadly perpendicular to side wall 126, flange 138 may extend obliquely relative to side wall 126, such as forming in conjunction with side wall 126 funnel shape, while still retaining the above-described advantageous features. In some embodiments, the flange 138 is not annular, but is located only partially around the rim of the side wall 126. In the depicted embodiment, the flange 138 has the same thickness as the side wall 126, however, in other embodiments, to increase resistance to deformation flange 138 is thicker than sidewall 126. Any increase in thickness of a particular portion to increase its strength should be weighed against the added heat capacity increase so that aerosol generating device 100 remains overall strong but efficient.

A plurality of protrusions 140 are formed in the inner surface of the side wall 126. The width of the protrusions 140 along the perimeter of the side wall 126 is small relative to their length parallel to the central axis of the side wall 126 (or, in a broad sense, in the direction from the base 112 to the open end 110 of the heating chamber 108) . In this example, there are four protrusions 140. Four is usually a suitable number of protrusions 140 for holding the cartridge holder 114 in a central position in the heating chamber 108, as will become apparent from the following discussion. In some embodiments, three protrusions may be sufficient, such as spaced (evenly) at approximately 120° intervals around the circumference of the side wall 126. The protrusions 140 have a variety of purposes, and the precise shape of the protrusions 140 (and corresponding depressions on the outer surface of the side wall 126) is chosen based on the desired result. In any case, the protrusions 140 extend to and engage with the cartridge holder 114 and are therefore sometimes referred to as engagement elements. Moreover, the terms protrusion and engagement element are used interchangeably herein. Similarly, if the projections 140 are provided by pressing the side wall 126 from the outside, such as by hydraulic drawing, pressing, etc., the term trough is also used interchangeably with the terms projection and engagement feature. The formation of protrusions 140 by indenting side wall 126 has the advantage that they are integral with side wall 126 and therefore have minimal effect on heat flow. In addition, the protrusions 140 do not contribute additional heat capacity, as would be the case when an additional element is added to the inner surface of the side wall 126 of the heating chamber 108. Moreover, by forming the protrusions 140 by indenting the side wall 126, the thickness of the side wall 126 remains substantially constant in the circumferential and/or axial direction even where the protrusions are provided. Finally, the indentation of the sidewall described increases the strength of the sidewall 126 by introducing portions extending transversely to the sidewall 126, thus making the sidewall 126 resistant to bending.

The heating chamber 108 is configured to receive a substrate holder 114. Typically, the substrate holder contains an aerosol-forming substrate 128, such as tobacco or other suitable aerosol-forming material, configured to be heated to generate an inhalable aerosol. In the first embodiment, the heating chamber 108 is sized to receive one portion of the aerosol forming substrate 128 in the form of a substrate holder 114, also known as a consumable, as shown, for example, in FIG. 3-6. However, this is not essential, and in other embodiments, heating chamber 108 is configured to receive aerosol forming substrate 128 in other forms, such as loose tobacco or tobacco packaged in other ways.

The aerosol generating device 100 functions both by conducting heat from the surface of the protrusions 140 engaged with the outer layer 132 of the substrate holder 114 and by heating the air in the air gap between the inner surface of the side wall 126 and the outer surface of the substrate holder 114. Those. there is convective heating of the aerosol generating substrate 128 as heated air is drawn through the aerosol generating substrate 128 as the user sucks through the aerosol generating device 100 (as described in more detail below). The width and height (i.e., the distance each projection 140 extends into the heating chamber 128) increases the surface area of the side wall 126 that conducts heat to the air, allowing the aerosol generating device 100 to reach an effective temperature more quickly.

The protrusions 140 on the inner surface of the side wall 126 extend towards the substrate holder 114 and, moreover, come into contact with it when it is introduced into the heating chamber 108 (see, for example, Fig. 6). This results in the heating of the aerosol forming substrate 128 also by conduction through the outer layer 132 of the substrate holder 114 .

It will be apparent that in order to conduct heat into the aerosol-forming substrate 128, the surface 145 of the projection 140 must engage with the outer layer 132 of the substrate holder 114. However, manufacturing tolerances may result in slight variations in the substrate holder 114 diameter. In addition, due to the relatively soft and compressible properties of the outer layer 132 of the substrate holder 114 and the aerosol forming substrate 128 held therein, any damage or rough handling of the substrate holder 114 may result in a reduction in diameter or a change in the cross-sectional shape to an oval or elliptical in areas where the outer layer 132 is expected to engage with the surfaces 145 of the projections 140. Accordingly, any change in the diameter of the substrate holder 114 may result in reduced heat

- 7 041326 contact between the outer layer 132 of the substrate holder 114 and the surface 145 of the projection 140, which adversely affects the conduction of heat from the surface 145 of the projection 140 through the outer layer 132 of the substrate holder 114 into the substrate 128, which forms an aerosol. To mitigate any change in substrate holder 114 diameter caused by manufacturing tolerances or damage, projections 140 are preferably sized to extend into heating chamber 108 a distance sufficient to cause compression of substrate holder 114 and thus provide a fit with interference between the surfaces 145 of the protrusions 140 and the outer layer 132 of the holder 114 of the substrate. This contraction of the outer layer 132 of the substrate holder 114 can also cause a longitudinal mark to be formed on the outer layer 132 of the substrate holder 114 and provide a visible indication that the substrate holder 114 has been used.

In FIG. 6(a) shows an enlarged view of the heating chamber 108 and the substrate holder 114. As can be seen, arrow B depicts the air flow paths that provide the above-described convective heating. As noted above, the heating chamber 108 may be in the form of a sleeve having a sealed, airtight base 112, meaning that since airflow through the sealed, airtight base 112 is not possible, air is forced to flow along the side of the substrate holder to enter the first end 134 of the substrate holder. holder 114 substrate. As noted above, the protrusions 140 extend into the heating chamber 108 a distance at least sufficient to contact the outer surface of the substrate holder 114 and usually to cause at least some compression of the substrate holder. Therefore, since the section in the sectional view of FIG. 6(a) passes through the projections 140 on the left and right of the figure, there is no air gap all the way along the heating chamber 108 in the plane of the figure. Instead, the airflow paths (arrows B) are shown as dashed lines in the region of the projections 140, indicating that the airflow path is in front of and behind the projections 140. In fact, a comparison with FIG. 2(a) shows that the airflow paths occupy four evenly spaced gap areas between the four projections 140. Of course, in some situations there may be more or less than four projections 140, in which case it remains a true commonality that the airflow paths air exists in the gaps between the protrusions.

Also in FIG. 6(a) highlights the deformation in the outer surface of the substrate holder 114 caused by its indentation by the projections 140 as the substrate holder 114 is inserted into the heating chamber 108. As noted above, the distance that the projections 140 extend into the heating chamber can advantageously be chosen as to be sufficient to cause any substrate holder 114 to contract. This (sometimes permanent) deformation during heating can contribute to the stability of the substrate holder 114 in that the deformation of the outer layer 132 of the substrate holder 114 creates a denser region of the aerosol forming substrate 128 near the first end 134 of the substrate holder 114. In addition, the resulting outer surface of the resulting shape of the substrate holder 114 provides the effect of holding at the edges of the denser region of the aerosol forming substrate 128 near the first end 134 of the substrate holder 114. In general, this reduces the likelihood of any loose substrate falling out of the first end 134 of the substrate holder 114, which could lead to fouling of the heating chamber 108. This effect is beneficial because, as described above, heating of the aerosol-forming substrate 128 can cause it. shrinkage, which increases the likelihood of loose substrate 128, forming an aerosol, from the first end 134 of the holder 114 of the substrate. Due to the described effect of deformation, this undesirable effect is weakened.

To ensure that the protrusions 140 come into contact with the substrate holder 114 (contact necessary to cause conductive heating, contraction and deformation of the aerosol-forming substrate), the manufacturing tolerances of each of: the protrusions 140; heating chamber 108; and a substrate holder 114. For example, the internal diameter of the heating chamber 108 may be 7.6±0.1 mm, the substrate holder 114 may have an external diameter of 7.0±0.1 mm, and the protrusions 140 may have a manufacturing tolerance of ±0.1 mm. In this example, assuming that the substrate holder 114 is centrally mounted in the heating chamber 108 (i.e., there is a uniform gap around the outside of the substrate holder 114), then the gap that each projection 140 must cover in order to contact the substrate holder 114 , is in the range from 0.2 to 0.4 mm. In other words, since each protrusion 140 spans some radial distance, the smallest possible value for this example is half the difference between the smallest possible diameter of the heating chamber 108 and the largest possible diameter of the substrate holder 114, or [(7.6-0.1)-(7. 0+0.1)]/2=0.2 mm.

The upper end of the range for this example is (for similar reasons) half the difference between the largest possible diameter of the heating chamber 108 and the smallest possible diameter of the substrate holder 114, or

[(7.6+0.1)-(7.0-0.1)]/2=0.4 mm.

In order to accurately ensure that the projections 140 are in contact with the substrate holder, it is obvious that in this

- 8 041326 each of them must extend at least 0.4 mm into the heating chamber. However, this does not take into account the manufacturing tolerance of the projections 140. If a projection of 0.4 mm is required, the actual manufacturing range is 0.4 ± 0.1 mm, or it varies from 0.3 to 0.5 mm. Some of them will not cover the maximum possible gap between the heating chamber 108 and the substrate holder 114. Therefore, the projections 140 in this example should be manufactured with a nominal projection distance of 0.5 mm, resulting in a range of 0.4 to 0.6 mm. It is sufficient to ensure that the protrusions 140 are always in contact with the substrate holder.

In general, if we write the inner diameter of the heating chamber 108 as D±δ _D , the outer diameter of the substrate holder 114 as d±δ _d , and the distance that the protrusions 140 extend into the heating chamber 108 as L±5L, then the distance that the protrusions 140 are supposed to extend into the heating chamber, should be chosen as (D + fol) - (d - foi) , ₍ L =----------------- ₊ | ₅ J where |δ _D | refers to the absolute value of the manufacturing tolerance of the inner diameter of the heating chamber 108, |5 _d |, refers to the absolute value of the manufacturing tolerance of the outer diameter of the cartridge holder 114, and |5L| pass into the heating chamber 108. To avoid ambiguous interpretation, if the inner diameter of the heating chamber 108 is D±6D=7.6±0.1 mm, then |5 _d |=0.1 mm.

In addition, manufacturing tolerances may result in minor changes in the density of the aerosol-forming substrate 128 in the substrate holder 114. These variations in the density of the aerosol forming substrate 128 may exist in both axial and radial directions within the same substrate holder 114 or between different substrate holders 114 manufactured in the same batch. Accordingly, it will also be apparent that in order to ensure relatively uniform conduction of heat in the aerosol forming substrate 128 in a particular substrate holder 114, it is important that the density of the aerosol forming substrate 128 is also relatively uniform. To mitigate any inhomogeneities in the density of the aerosol forming substrate 128, the projections 140 may be sized to extend into the heating chamber 108 a distance sufficient to cause compression of the aerosol forming substrate 128 in the substrate holder 114, which can increase conduction of heat through an aerosol-forming substrate 128 by eliminating air gaps. In the depicted embodiment, protrusions 140 extending into heating chamber 108 by approximately 0.4 mm are suitable. In other examples, the distance that the projections 140 extend into the heating chamber 108 can be defined as a percentage of the distance across the heating chamber 108. For example, the projections 140 may extend from 3% to 7%, such as approximately 5% of the distance across the heating chamber 108 In another embodiment, the limited diameter described by the protrusions 140 in the heating chamber 108 is 6.0 to 6.8 mm, more preferably 6.2 to 6.5 mm, and in particular 6.2 mm (±0 .5 mm). Each of the plurality of protrusions 140 spans a radial distance of 0.2 to 0.8 mm, and most preferably 0.2 to 0.4 mm.

As for the protrusions/cavities 140, their width corresponds to the distance along the perimeter of the side wall 126. Similarly, the direction of their length runs transversely to it, passing, in a broad sense, from the base 112 to the open end of the heating chamber 108 or to the flange 138, and their height corresponds to the distance , which the protrusions extend from the side wall 126. It should be noted that the gap between adjacent protrusions 140, the side wall 126 and the outer layer 132 of the substrate holder 114 defines the area available for air flow. The result of this is that the smaller the distance between adjacent protrusions 140 and/or the height of the protrusions 140 (i.e., the distance that the protrusions 140 extend into the heating chamber 108), the more the user needs to suck in air in order to draw it through aerosol generating device 100 (this is known as increased draw resistance). It will be apparent that (assuming the protrusions 140 are in contact with the outer layer 132 of the substrate holder 114) it is the width of the protrusions 140 that determines the reduction in the air flow path between the side wall 126 and the substrate holder 114. Conversely (also assuming that the protrusions 140 are in contact with the outer layer 132 of the substrate holder 114), increasing the height of the protrusions 140 results in more compression of the aerosol generating substrate, which eliminates air gaps in the aerosol generating substrate 128, and also increases resistance to draw. There are two parameters that can be adjusted to obtain a satisfactory draw resistance that is neither too low nor too high. The heating chamber 108 can also be made larger to increase the airflow path between the side wall 126 and the substrate holder 114, however there is a practical limit to this before the heater 124 starts to become ineffective when the gap becomes too large. Typically, a gap around the outer surface of the substrate holder 114, having a size of from 0.2 to 0.4 mm or from

- 9 041326

0.2 to 0.3 mm is a satisfactory compromise to fine-tune draw resistance within acceptable limits by changing the dimensions of the projections 140. The air gap around the outside of the substrate holder 114 can also be changed by changing the number of projections 140. Any number of projections 140 (from one or more) provides at least some of the benefits set forth herein (increasing the heating area, providing compression, providing conductive heating of the aerosol forming substrate 128, adjusting the air gap, etc.). Four is the smallest number where substrate holder 114 is securely held in central (ie, coaxial) alignment with heating chamber 108. In another possible design, there are only three protrusions that are spaced 120° apart. Designs containing fewer than four projections 140 tend to allow the substrate holder 114 to be pressed against a portion of the sidewall 126 between two of the projections 140. It is clear that, given limited space, providing very large numbers of projections (e.g., thirty or more) has tending to a situation where there is little or no gap between them, which can completely block the air flow path between the outer surface of the substrate holder 114 and the inner surface of the side wall 126, which greatly reduces the ability of the aerosol generating device to provide convective heating. However, such designs can still be used in conjunction with the possibility of providing an opening in the center of the base 112 to form a channel for air flow. Typically, projections 140 are evenly spaced around the perimeter of sidewall 126, which can help provide uniform compression and heating, although some embodiments may be asymmetrically placed depending on the exact result required.

It will be apparent that the size and number of protrusions 140 also allow for adjustment of the balance between conductive and convective heating. By increasing the width of the protrusion 140 (the distance that the protrusion 140 extends along the perimeter of the side wall 126) in contact with the substrate holder 114, the available perimeter of the side wall 126, which acts as an airflow channel (arrows B in FIG. 6), is reduced. and 6(a)), thereby reducing the convective heating provided by the aerosol generating device 100. However, as the wider projection 140 comes into contact with the substrate holder 114 over a larger portion of the perimeter, the conductive heating provided by the aerosol generating device 100 increases. By adding more protrusions 140, a similar effect can be observed in that the convective perimeter of the side wall 126 decreases as the conduction channel increases, by increasing the total contact surface area between the protrusion 140 and the substrate holder 114. It should be noted that the length of the protrusion 140 also reduces the volume of air in the heating chamber 108 that is heated by the heater 124 and reduces convective heating, while increasing the contact surface area between the protrusion 140 and the substrate holder and increasing conductive heating. Increasing the distance each protrusion 140 extends into heating chamber 108 can improve conductive heating without significantly reducing convective heating. Therefore, the aerosol generating device 100 can be configured to balance conductive and convective type heating by varying the number and size of protrusions 140 as described above. that conductive heating is a suitable means of transferring heat to the substrate holder 114 and, consequently, to the aerosol forming substrate 128, since the heated portions of the side wall 126 can, in a broad sense, correspond to the locations of the protrusions 140, which means that the generated heat is conducted to the substrate holder 114 by projections 140 and is not conducted away from it. At locations that heat up but do not correspond to the protrusions 140, heating of the sidewall 126 leads to the convective heating described above.

As shown in FIG. 1-6, projections 140 are elongated, i. their length is greater in length than in width. In some cases, the protrusions 140 may be five, ten, or even twenty-five times their width in length. For example, as noted above, in one example, the protrusions 140 may extend into the heating chamber 108 by 0.4 mm, and may also be 0.5 mm wide and 12 mm long. These dimensions are suitable for heating chamber 108 with a length of 30 mm to 40 mm. In this example, the projections 140 do not extend the full length of the heating chamber 108 because, in the example shown, they are shorter than the heating chamber 108. Therefore, each projection 140 has a top edge 142a and a bottom edge 142b. The top edge 142a is the part of the protrusion 140 closest to the open end 110 of the heating chamber 108 and also closest to the flange 138. The bottom edge 142b is the end of the protrusion 140 closest to the base 112. It can be seen that above the top edge 142a (closer to the open end than the top edge 142a) and below the bottom edge 142b (closer to the base 112 than the bottom edge 142b), the side wall 126 has no protrusions 140, i. in these parts, the side wall 126 is not deformed or depressed. In some examples, the projections 140 are longer and extend into

- 10 041326 all the way to the top and/or bottom of the side wall 126 so that one or both of the following is true: the top edge 142a is aligned with the open end 110 of the heating chamber 108 (or flange 138);

and the bottom edge 142b is aligned with the base 112. Moreover, in these cases there may not even be a top edge 142a and/or a bottom edge 142b.

It may be advantageous that the projections 140 do not extend the entire length of the heating chamber 108 (eg, from the base 112 to the flange 138). At the upper end, as will be described below, the upper edge 142a of the projection 140 can be used as an indicator for the user to ensure that the user does not insert the substrate holder 114 too far into the aerosol generating device 100. However, it may be useful to heat not only the regions of the substrate holder 114 containing the aerosol generating substrate 128, but other regions as well. The reason for this is that after the aerosol is generated, it is useful to keep it at a high temperature (above room temperature, but not so high as to burn the user) to prevent re-condensation, which in turn can degrade the user experience. Therefore, the region of effective heating of the heating chamber 108 extends beyond the expected location of the aerosol generating substrate 128 (ie, above the heating chamber 108, towards the open end). This means that the heating chamber 108 extends above the upper edge 142a of the protrusion 140 or, equivalently, that the protrusion 140 does not extend all the way to the open end of the heating chamber 108. heating chamber 108 may cause some of the aerosol forming substrate 128 to fall out of the substrate holder 114 and foul the heating chamber 108. Therefore, it may be advantageous to locate the bottom edge 142b of the projections 140 further from the base 112 than the expected position of the end 134 of the substrate holder 114 is. .

In some embodiments, the projections 140 are not elongated and have a width approximately equal to their length. For example, they may have a width equal to the height (eg, have a square or circular profile when viewed in the radial direction), or they may have a length of two to five times the width. It should be noted that the centering effect provided by the projections 140 can be achieved even when the projections 140 are not elongated. In some instances, they may be a plurality of sets of protrusions 140, such as an upper set near the open end of the heating chamber 108 and a lower set spaced apart from the upper set and near the base 112. This may help to keep the substrate holder 114 in alignment while simultaneously the reduction in drag resistance introduced by a single set of protrusions 140 at the same distance. The two sets of protrusions 140 may be substantially the same, or they may vary in length or width, or in the number or placement of protrusions 140 located around the circumference of sidewall 126.

In side view, projections 140 are shown as having a trapezoidal profile. By this is meant that the profile along the length of each projection 140, eg the average longitudinally directed cross section of the projection 140, is approximately trapezoidal. Those. the top edge 142a is broadly flat and tapers to merge with the side wall 126 near the open end 110 of the heating chamber 108. In other words, the top edge 142a has a beveled profile shape. Likewise, the protrusion 140 has a bottom 142b that is broadly flat and tapering to merge with the side wall 126 near the base 112 of the heating chamber 108. That is. the bottom edge 142b has a bevelled profile shape. In other embodiments, the top and/or bottom edges 142a, 142b do not taper towards sidewall 126, but instead extend from sidewall 126 at an angle of approximately 90°. In other embodiments, the top and/or bottom edges 142a, 142b are curved or rounded. The connection of the upper and/or lower edges 142a, 142b, in a broad sense, is a flat area that comes into contact with and/or compresses the holder 114 of the substrate. The flat contact portion can assist in providing uniform compression and conductive heating. In other examples, the flat portion, in contrast, may be a curved portion curved outward to contact the substrate holder 128, such as having a polygonal or curved profile (such as a segment of a circle).

In cases where the protrusions 140 have an upper edge 142a, the protrusions 140 also function to prevent over-insertion of the substrate holder 114. As most clearly shown in FIG. 4 and 6, the substrate holder 114 has a lower portion containing the aerosol generating substrate 128 that terminates at some distance along the substrate holder 114 at the boundary of the aerosol generating substrate 128. The aerosol forming substrate 128 is generally more compressible than the other regions 130 of the substrate holder 114. Therefore, the user inserting the substrate holder 114 feels an increase in resistance when the upper edge 142a of the protrusions 140 aligns with the boundary of the aerosol generating substrate 128 due to the reduced compressibility of other regions 130 of the substrate holder 114. To achieve this result, the part(s) of the base 112 that is(are) in contact with the substrate holder 114 must be located (should be located) relative to the upper edge 142a of the protrusion 140 at a distance equal to the length of the substrate holder 114 occupied by the substrate 128, forming an aerosol. In some examples, the aerosol-forming substrate 128 occupies approximately 20 mm of the substrate holder 114, so the distance between the top edge 142a of the projection 140 and the portions of the base contacted by the substrate holder 114 when inserted into the heating chamber 108 is also approximately 20 mm.

As shown, the base 112 also includes a platform 148. The platform 148 is formed in a single step in which the base 112 is pressed from below (for example, by hydraulic molding or mechanical pressing as part of the formation of the heating chamber 108) so that a depression is left on the outer surface (bottom surface) of the base 112 and a platform 148 on the inner surface (upper surface inside the heating chamber 108) of the base 112. If the platform 148 is formed in this way, for example with a corresponding depression, these terms are used interchangeably. In other cases, the platform 148 may be formed from a separate piece, which is attached to the base 112 separately, or by cutting parts of the base 112 so that the platform 148 remains; in each of these two cases, the corresponding cavity is not necessary. The latter cases mentioned may allow for a greater variety of platform 148 shapes as they are not based on deformation of the base 112, which (although a convenient way) limits the complexity with which the shape can be selected. Although the shape shown is, in a broad sense, circular, of course, a wide variety of shapes are present that will achieve the desired results detailed herein, including, but not limited to: polygonal shapes, curved shapes, including many forms of one or more of these types. Moreover, although the platform 148 is shown as centrally located, in some cases there may be one or more elements of the platform located at a distance from the center, for example, at the edges of the heating chamber 108. Typically, the platform 148 has a broadly flat top. part, however, semi-spherical or dome-shaped platforms, rounded at the top, are also provided.

As noted above, the distance between the top edge 142a of the protrusion 140 and the portions of the base 112 that the substrate holder 114 comes into contact with can be carefully chosen to match the length of the aerosol generating substrate 128 to provide an indication to the user that the substrate holder 114 has been inserted. into the aerosol generating device 100 at the required distance. In cases where the platform 148 on the base 112 is missing, this only means that the distance from the base 112 to the top edge 142a of the protrusion 140 must match the length of the substrate 128 forming the aerosol. If a platform 148 is present, then the length of the aerosol generating substrate 128 should correspond to the distance between the top edge 142a of the projection 140 and the uppermost part of the platform 148 (i.e., in some examples, the portion closest to the open end 110 of the heating chamber 108). In another example, the distance between the top edge 142a of the projection 140 and the uppermost part of the platform 148 is slightly less than the length of the aerosol forming substrate 128. This means that the tip 134 of the substrate holder 114 must extend slightly beyond the uppermost part of the platform 148, thus causing the aerosol forming substrate 128 to be compressed at the end 134 of the substrate holder 114. Moreover, this compression effect may occur even in instances where the protrusions 140 on the inner surface of the side wall 126 are absent. This compression can help prevent the aerosolizing substrate 128 at the end 134 of the substrate holder 114 from falling out into the heating chamber 108, thereby reducing the need for cleaning the heating chamber 108, which can be a difficult and difficult task. In addition, compression contributes to compression of the end 134 of the substrate holder 114, which thus weakens the above-described effect, when compression of the area using projections 140 extending from the side wall 126 is inappropriate because they tend to increase the likelihood of the substrate 128 falling out, forming an aerosol, from the holder 114 of the substrate.

The platform 148 also provides an area in which any aerosol forming substrate 128 dropped from the substrate holder 114 can be collected without blocking the airflow path to the tip 134 of the substrate holder 114. For example, platform 148 divides the bottom end of heating chamber 108 (i.e., the portions closest to base 112) into raised portions forming platform 148 and lower portions forming the remainder of base 112. The lower portions may receive loose particles of substrate 128 forming aerosol falling out of the substrate holder 114 while air can still flow over these loose particles of the aerosol forming substrate 128 to the end of the substrate holder 114. To achieve this result, platform 148 may be positioned about 1 mm higher than the remainder of base 112. Platform 148 may have a diameter smaller than that of substrate holder 114 so that it does not obstruct the flow of air through aerosol generating substrate 128. Preferably platform 148 has a diameter of 0.5 to 0.2 mm, most preferably 0.45 to 0.35 mm, such as 0.4 mm (±0.03 mm).

The aerosol generating device 100 has a button 116 actuated by the user. In the first embodiment, a user-operated button 116 is located on the side wall 118 of the shell 102. The user-operated button 116 is positioned such that when the user-operated button 116 is actuated, for example, by pressing the button 116 actuated by the user, the aerosol generating device 100 is activated to heat the aerosol generating substrate 128 to generate an inhalable aerosol. In some embodiments, the user actuated button 116 is also configured to allow the user to activate other functions of the aerosol generating device 100 and/or provide a light signal to indicate the status of the aerosol generating device 100. In other examples, a separate indicator light or indicators (eg, one or more LEDs or other suitable light sources) may be provided to indicate the status of the aerosol generating device 100. In the context of this document, status can mean one or more of the following: remaining battery power, heater status (eg, on, off, error, etc.), device status (eg, ready to puff or not ready), or other status indication. , for example, error modes, indicating the number of puffs or the number of full substrate holders 114 consumed or remaining until the power supply is completely discharged, etc.

In the first embodiment, the aerosol generating device 100 is electrically powered. Those. it is configured to heat the aerosol-forming substrate 128 using electrical power. To this end, the aerosol generating device 100 has a power source 120 such as a battery. The power supply 120 is connected to the control circuit 122. The control circuit 122 is in turn connected to the heater 124. The user actuated button 116 is configured to connect and disconnect the power supply 120 to the heater 124 via the control circuit 122. In this embodiment, the power supply 120 is located towards the first end 104 of the aerosol generating device 100. This allows the power source 120 to be located at a distance from the heater 124 located towards the second end 106 of the aerosol generating device 100. In other embodiments, heating chamber 108 is heated in other ways, such as by burning a combustible gas.

The heater 124 is attached to the outer surface of the heating chamber 108. The heater 124 is provided on a metal layer 144, which is itself provided in contact with the outer surface of the side wall 126. The metal layer 144 forms a strip around the heating chamber 108, corresponding to the shape of the outer surface of the side wall 126. The heater 124 shown as centered on metal layer 144, with metal layer 144 extending equally up and down past heater 124. As shown, heater 124 is located entirely on metal layer 144 such that metal layer 144 covers an area greater than the area occupied by the heater 124. Heater 124, as shown in FIG. 1-6 is attached to the middle portion of the heating chamber 108 between the base 112 and the open end 110 and is attached to the outer surface area covered by the metal layer 114. It should be noted that in other embodiments, the heater 124 may be attached to other parts of the heating chamber 108 or may be contained in the side wall 126 of the heating chamber 108, and that the outer part of the heating chamber 108 contains the metal layer 144 is not essential.

As shown in FIG. 7, heater 124 includes heating element 164, electrical connection tracks 150, and protective film 166. Heating element 164 is configured such that when current flows through heating element 164, heating element 164 heats up and its temperature increases. The heating element 164 is shaped so that it does not contain sharp corners. Sharp corners may contain hot spots in heater 124 or form melting points. Heating element 164 also has a uniform width, and portions of element 164 that extend close together are held at approximately equal distance. In the heating element 164 of FIG. 7 shows two resistive paths 164a, 164b, each traversing a serpentine path around an area of heater 124 covering as much area as possible while still meeting the criteria described above. These paths 164a, 164b in FIG. 7 are electrically parallel to each other. It should be noted that other numbers of paths may be used, such as three paths, one path, or multiple paths. Paths 164a, 164b do not intersect, as this would create a short circuit. Heating element 164 is designed to be resistive to provide the correct energy density for the desired level of heat. In some examples, heating element 164 has a resistance of 0.4 to 2.0 ohms, particularly preferably 0.5 to 1.5 ohms, and more specifically 0.6 to 0.7 ohms.

Electrical connection tracks 150 are shown as part of heater 124, but in some embodiments they may be replaced by wires or other connectors. Electrical connections 150 are used to supply power to the heating element 164 and form a circuit with the power source 120.

Electrical connection tracks 150 are shown as extending vertically downward from heating element 164. With heater 124 in place, electrical connections 150 extend beyond base 112 of heating chamber 108 and through base 156 of heat insulator 152 for connection to control circuit 122.

The protective film 166 may either be a single sheet with a heating element 164 attached, or may form a wrapper in which the heating element is sandwiched between two sheets 166a, 166b. In some embodiments, the protective film 166 is formed from polyimide. In some embodiments, the thickness of the protective film 166 is minimized to reduce the thermal capacity of the heater 124. For example, the thickness of the protective film 166 may be 50 microns, or 40 microns, or 25 microns.

Heating element 164 is attached to side wall 108. In FIG. 7, heating element 164, by careful sizing of heater 124, is configured to wrap once around heating chamber 108. This provides approximately even distribution of heat generated by heater 124 near the surface covered by heater 124. a full turn of the heater 124 can be wrapped around the heating chamber 108 an integer number of times.

It should also be noted that the height of the heater 124 is from about 14 to 15 mm. The circumference of the heater 124 (or its length prior to use in the heating chamber 108) is about 24 to 25 mm. The height of the heating element 164 may be less than 14 mm. This allows the heating element 164 to be located entirely within the protective film 166 of the heater 124 with a border around the heating element 164. Therefore, the area covered by the heater 124 may be approximately 3.75 cm ² in some embodiments.

The power used by heater 124 is supplied by power source 120, which in this embodiment is in the form of a battery (or battery). The voltage provided by the power supply 120 is a regulated voltage or boost voltage. For example, power supply 120 may be configured to generate a voltage in the range of 2.8 to 4.2 V. In one example, power supply 120 is configured to generate a voltage of 3.7 V. Assuming the approximate resistance of heating element 164 in one embodiment implementation of 0.6 ohms and an approximate voltage of 3.7 V, this will provide an output power in the heating element 164 of approximately 30 watts. It should be noted that based on approximate resistances and voltages, the output power can be from 15 to 50 watts. The battery constituting the power supply 120 may be a rechargeable battery or, alternatively, may be a disposable battery 120 . The power supply is typically configured to supply power for 20 or more heating cycles. This allows the user to use a full pack of 20 substrate holders 114 per charge of the aerosol generating device 100. The battery may be a lithium ion battery or any other type of commercially available battery. It can be, for example, an 18650 type battery or an 18350 type battery. If the battery is an 18350 type battery, the aerosol generating device 100 can be configured to store a charge sufficient for 12 heating cycles or even 20 cycles. heating, which allows the user to consume 12 or even 20 substrate holders 114.

One important value for the heater 124 is the power generated by it per unit area. It is a measure of how much heat can be provided by the heater 124 to the region of contact with it (in this case, the heating chamber 108). For the described examples, it is in the range from 4 to 13.5 W/cm ² . Depending on the design, heaters are typically rated for maximum power densities between 2 and 10 W/ ^cm2 . Therefore, in some of these embodiments, a layer 144 of copper or other conductive metal may be provided on the heating chamber 108 to efficiently conduct heat from the heater 124 and reduce the likelihood of damage to the heater 124.

The power delivered by heater 124 may be constant in some embodiments, and may not be constant in other embodiments. For example, heater 124 may provide variable power throughout an operating cycle, or more specifically, a pulse width modulation cycle. This allows the power to be delivered in pulses and the time-averaged power output of the heater 124 to be easily controlled by simply choosing the ratio of on and off times. The output of heater 124 can also be controlled by additional controls such as current or voltage control.

As shown in FIG. 7, the aerosol generating device 100 has a temperature sensor 170 for detecting the temperature of the heater 124 or the environment surrounding the heater 124. The temperature sensor 170 may be, for example, a thermistor, a thermocouple, or any other thermometer. For example, a thermistor may be formed from a glass bead enclosing a resistive material connected to a voltmeter and having a known current flow through it. Thus, as the temperature of the glass changes, the resistance of the resistive material changes in a predictable manner, and therefore the temperature can be inferred from the voltage drop across it at DC (constant voltage modes are also possible). In some embodiments, the temperature sensor 170 is located on the surface of the heating chamber 108, such as during

- 14 041326 depression formed in the outer surface of the heating chamber 108. The depression may be one of the depressions described elsewhere in this document, for example, as part of the protrusions 140, or may be a depression specially provided to hold the temperature sensor 170. In the depicted embodiment, a temperature sensor 170 is provided on the protective layer 166 of the heater 124. In other embodiments, the temperature sensor 170 is integral with the heating element 164 of the heater 124 in that the temperature is determined by monitoring the change in the resistance of the heating element 164.

In the aerosol generating device 100 according to the first embodiment, the time to the first puff after the aerosol generating device 100 is started is an important parameter. The user of the aerosol generating device 100 will find it preferable to start inhaling the aerosol from the substrate holder 128 as soon as possible, with a minimum delay time between starting the aerosol generating device 100 and inhaling the aerosol from the substrate holder 128. Therefore, during the first stage of heating, the power supply 120 supplies 100% of the available power to the heater 124, for example by setting the duty cycle as always on or by controlling the product of voltage and current until it reaches its maximum possible value. This may take a period of 30 seconds, or more preferably a period of 20 seconds, or any period until the temperature sensor 170 gives a reading corresponding to 240°C. Typically, the substrate holder 114 can operate optimally at 180° C., however, it may still be advantageous to heat the temperature sensor 170 above this temperature so that the user can remove the aerosol from the substrate holder 114 as quickly as possible. The reason for this is that the temperature of the aerosol generating substrate 128 typically lags (i.e., is lower than) the temperature sensed by the temperature sensor 170 because the aerosol generating substrate 128 is heated by convection of heated air through the aerosol generating substrate 128. aerosol, and as heat is conducted between the projections 140 and the outer surface of the substrate holder 114. In comparison, the temperature sensor 170 is kept in satisfactory thermal contact with the heater 124 and therefore measures a temperature near the temperature of the heater 124 rather than the temperature of the aerosol generating substrate 128. In fact, accurately measuring the temperature of the aerosol generating substrate 128 can be difficult, so the heating cycle is often empirically determined by testing various heating profiles and heater temperatures and monitoring the aerosol generated by the aerosol generating substrate 128 for the various components of the aerosol generated at a given temperature. Optimal cycles provide aerosols as quickly as possible while avoiding the generation of combustion products due to overheating of the aerosol generating substrate 128.

The temperature sensed by the temperature sensor 170 can be used to set the level of power delivered by the power element 120, for example by forming a feedback loop in which the temperature sensed by the temperature sensor 170 is used to control the power cycle of the heater. The heating cycle described below may take place for the case in which the user wishes to consume one substrate holder 114.

In the first embodiment, the heater 124 extends around the heating chamber 108. That is, the heater 124 surrounds the heating chamber 108. In more detail, the heater 124 extends around the side wall 126 of the heating chamber 108, but not around the base 112 of the heating chamber 108. The heater 124 does not extend along the entire side wall 126 of the heating chamber 108. Instead, it extends completely around the side wall 126 of the heating chamber 108. wall 126, but only partially along the length of side wall 126, the length in the context of this document is the distance from the base 112 to the open end 110 of the heating chamber 108. In other embodiments, the implementation of the heater 124 runs the entire length of the side wall 126. In other embodiments embodiment, heater 124 comprises two heating portions separated by a gap that exposes the central portion of heating chamber 108, such as the portion of side wall 126 midway between base 112 and open end 110 of heating chamber 108. In other embodiments, since heating chamber 108 is in the form of sleeves s, heater 110 is likewise shaped like a sleeve, for example, it extends completely around the base 112 of heating chamber 108. In other embodiments, heater 124 includes a plurality of heating elements 164 distributed proximate heating chamber 108. In some embodiments, there are spaces between heating elements 164; in other embodiments, they overlap with each other. In some embodiments, the heating elements 164 may be spaced around the circumference of the heating chamber 108 or sidewall 126, such as laterally, in other embodiments, the heating elements 164 may be spaced along the length of the heating chamber 108 or sidewall 126, such as longitudinally. It should be understood that the heater 124 according to the first embodiment is provided on the outer surface of the heating chamber 108 outside the heating chamber 108. To enable satisfactory heat transfer between the heater 124 and the heating chamber 108, the heater 124 is provided in satisfactory thermal contact with the heating chamber 108.

The metal layer 144 may be formed from copper or any other material (for example,

- 15 041326 metal or alloy) with high thermal conductivity, such as gold or silver. In the context of this document, the term high thermal conductivity may refer to a metal or alloy having a thermal conductivity of 150 W/mK or more. The metal layer 144 may be deposited in any suitable manner, such as by electroplating. Other methods for applying the layer 144 include gluing a metal tape to the heating chamber 108, chemical vapor deposition, physical vapor deposition, etc. Although electrodeposition is a convenient method for applying the layer 144, it requires that part, on which deposited coating layer 144, was electrically conductive. This is not required in other deposition methods, and these other methods open the possibility of forming the heating chamber 108 from materials that are not electrically conductive, such as ceramics, which may have useful thermal properties. In addition, if a layer is described as metallic, although it should normally be understood to mean formed from a metal or alloy, in the context of this document it refers to a material with a relatively high thermal conductivity (>150 W/mK). When electrodepositing the metal layer 144, it may first be necessary to form a tightening layer on the side wall 126 to ensure that the electrodeposited layer adheres to the outer surface. For example, if the metal layer 144 is copper and the sidewall 126 is stainless steel, a nickel puff layer is often used to ensure satisfactory adhesion. The electrodeposited layers and the deposited layers have the advantage of direct contact between the metal layer 144 and the material of the side wall 126, thus increasing the thermal conductivity between the two elements.

Whichever method is used to form the metal layer 144, the thickness of the layer 144 is usually somewhat less than the thickness of the side wall 126. For example, the range of thicknesses of the metal layer can be from 10 to 50 microns or from 10 to 30 microns, such as about 20 microns. When a puff layer is used, it is even thinner than the metal layer 144, eg 10 µm or even 5 µm thick. As described in more detail below, the purpose of the metal layer 144 is to spread the heat generated by the heater 124 over an area larger than the area occupied by the heater 124. After successfully achieving this effect, the benefit of further increasing the thickness of the metal layer 144 becomes small, since this only increases the heat capacity and reduces the efficiency of the aerosol generating device 100.

From FIG. 1-6, it will be apparent that the metal layer 144 only extends over a portion of the outer surface of the side wall 126. This not only reduces the heat capacity of the heating chamber 108, but also allows the heating area to be determined. In a broad sense, the metal layer 144 has a higher thermal conductivity than the side wall 126, so the heat generated by the heater 124 quickly spreads over the area covered by the metal layer 144, however, because the side wall 126 is not only thin, but also has relatively lower thermal conductivity than the metal layer 144, heat remains relatively localized in the areas of the side wall 126 covered by the metal layer 144. Selective electrodeposition is achieved by masking portions of the heating chamber 108 with a suitable tape (e.g., polyester or polyimide) or silicone rubber molding. In other deposition methods, other tapes and masking methods may be used as needed.

As shown in FIG. 1-6, the metal layer 144 overlaps the entire length of the heating chamber 108 along which the protrusions/cavities 140 extend. heat. The length of the metal layer 144, in a broad sense, corresponds to the length of the heating region, i. it is often not necessary for the metal layer to extend to the top and bottom of the heating chamber 108 (ie, the parts closest to the open end and base 112). As noted above, the area to be heated of the substrate holder 114 begins a short distance above the boundary of the aerosol forming substrate 128 and extends towards the end 134 of the substrate holder 114, but in many cases does not include the end 134 of the substrate holder 114. As noted above, the metal layer 144 acts so that the heat generated by the heater 124 spreads over an area larger than the area occupied by the heater 124 itself. design value in W/cm ² and the surface area occupied by the heater 124, since the generated heat spreads over a larger area, so the effective area of the heater 124 is greater than the surface area actually occupied by the heater 124.

Since the heating zone may be defined by the portions of the side wall 126 that are coated with the metal layer 144, the exact placement of the heater 124 on the outside of the heating chamber 108 is less critical. For example, instead of needing to align heater 124 at a specific distance from the top or bottom of sidewall 126, metal layer 144 can instead be formed in a very specific area, and heater 124 placed over metal layer 144 spreads heat over the area of metal layer 144 , or heating zone as described above. The masking process is often easier to standardize for electrodeposition

- 16 041326 or deposition than accurately align the heater 124.

Similarly, if there are protrusions 140 formed by indentation of the side wall 126, the depressions represent portions of the side wall 126 that will not be in contact with the heater 124 wrapped around the heating chamber 108; instead, heater 124 tends to close the valley while maintaining a gap. The metal layer 144 can help mitigate this effect because, by conducting through the metal layer 144, heat from the heater 124 is received even by portions of the sidewall 126 that are not in direct contact with the heater 124. In some cases, the heating element 164 may be located with the possibility of minimizing the overlap between the heating element 164 and the cavity on the outer surface of the side wall 126, for example, by positioning the heating element 164 so that it crosses the cavity, but does not pass along the cavity. In other cases, the heater 124 is located on the outer surface of the side wall 126 so that the portions of the heater 124 overlying the troughs are gaps between the heating elements 164. Whatever method is chosen to reduce the effect of the heater 124 overlying the trough, the metal layer 144 weakens this effect by conducting heat into the cavity. In addition, the metal layer 144 provides additional thickness in the recessed areas of the sidewalls 126, thereby providing additional structural support to these areas. Moreover, the additional thickness provided by the metal layer 126 increases the strength of the thin side wall 126 in all parts covered with the metal layer 144.

The metal layer 144 may be formed before or after the step in which depressions are formed in the outer surface of the side wall 126 to provide protrusions 140 extending into the heating chamber 108. It is preferable to form the depressions before the formation of the metal layer, since after the formation of the metal layer 144 such processes , such as annealing, can damage the metal layer 144, and stamping the side wall 126 to form the protrusions 140 becomes more difficult due to the increased thickness of the side wall 126 in combination with the metal layer 144. sidewall 126, it is much easier to form the metal layer 144 to extend beyond the troughs (ie, above and below), since masking the outer surface of the sidewall 126 to extend into the trough is difficult. The presence of any gap between the mask and the side wall 126 can lead to the deposition of the metal layer 144 under the mask.

Wrapped around the heater 124 is an insulating layer 146. This insulating layer 146 is under tension, thus providing a compressive force against the heater 124 to tightly hold the heater 124 against the outer surface of the side wall 126. Preferably, this insulating layer 146 is a heat shrinkable material. This allows the heat insulating layer 146 to be tightly wrapped around the heating chamber (over the heater 124, metal layer 144, etc.) and then heated. When heated, the heat insulating layer 146 contracts and presses the heater 124 tightly against the outer surface of the side wall 126 of the heating chamber 108. This eliminates any air gaps between the heater 124 and the side wall 126, and keeps the heater 124 in quite satisfactory thermal contact with the side wall. This, in turn, provides high efficiency because the heat generated by the heater 124 heats the sidewall (and then the aerosol forming substrate 128) rather than being wasted in heating the air or leaking away in other ways.

In a preferred embodiment, a heat shrink material is used, such as a treated polyimide tape, which shrinks in only one dimension. For example, in the example of a polyimide tape, the tape may be configured to shrink only in the length direction. This means that the tape can be wrapped around the heating chamber 108 and the heater 124 and that, when heated, it will contract and press the heater 124 against the side wall 126. Due to the shrinkage of the heat insulating layer 146 in the length direction, the force thus generated is uniform and directed inward. Where there is shrinkage of the tape in the transverse direction (in width), it can cause collapse of the heater 124 or the tape itself. This, in turn, can cause gaps to form and reduce the efficiency of the aerosol generating device 100.

With reference to FIG. 3-6, substrate holder 114 comprises a pre-packaged amount of aerosol generating substrate 128 along with aerosol collection area 130 that are wrapped in outer layer 132. Aerosol generating substrate 128 is positioned toward the first end 134 of substrate holder 114. The aerosol forming substrate 128 extends across the entire width of the substrate holder 114 within the outer layer 132. They also abut each other for some distance along the substrate holder 114, meeting at a boundary. In general, substrate holder 114 is generally cylindrical. An aerosol generating device 100 is shown in FIG. 1 and 2 without substrate holder 114. In FIG. 3 and 4, the substrate holder 114 is shown above the aerosol generating device 100, but is not loaded into the aerosol generating device 100. In FIG. 5 and 6, the substrate holder 114 is shown loaded into the aerosol generating device 100.

When the user wants to use the aerosol generating device 100, the user first loads the substrate holder 114 into the aerosol generating device 100. This includes inserting the substrate holder 114 into the heating chamber 108. The substrate holder 114 is inserted into the heating chamber 108 in such an orientation that the first end 134 of the substrate holder 114, towards which the aerosol generating substrate 128 is located, enters the heating chamber 108. The substrate holder 114 is inserted into the heating chamber 108 until the first end 134 of the substrate holder 114 leans against the platform 148 extending inwardly from the base 112 of the heating chamber 108, i. e. until the substrate holder 114 can no longer be inserted further into the heating chamber 108. In the embodiment shown, as described above, there is an additional effect of interaction between the upper edge 142a of the protrusions 140 and the boundary of the aerosol generating substrate 128 with the less compressible adjacent region of the holder 114 substrate, which alerts the user that the substrate holder 114 has been inserted into the aerosol generating device 100 at a sufficient distance. As seen in FIG. 3 and 4, when the substrate holder 114 is inserted into the heating chamber 108 as far as possible, only a portion of the length of the substrate holder 114 is inside the heating chamber 108. The remainder of the length of the substrate holder 114 protrudes from the heating chamber 108. At least a portion of the remainder of the length of the substrate holder 114 also protrudes from the second end 106 of the aerosol generating device 100. In the first embodiment, the rest of the length of the substrate holder 114 protrudes from the second end 106 of the aerosol generating device 100. Those. the open end 110 of the heating chamber 108 coincides with the second end 106 of the aerosol generating device 100. In other embodiments, all or substantially all of the substrate holder 114 may be accommodated in the aerosol generating device 100 such that the substrate holder 114 does not protrude or substantially protrude from the aerosol generating device 100.

When the substrate holder 114 is inserted into the heating chamber 108, the aerosol forming substrate 128 in the substrate holder 114 is at least partially located in the heating chamber 108. In the first embodiment, the aerosol forming substrate 128 is entirely in the heating chamber 108. Moreover, a pre-packaged amount of aerosol-forming substrate 128 in the substrate holder 114 is arranged to extend along the substrate holder 114 from the first end 134 of the substrate holder 114 for a distance that is approximately (or even exactly) equal to the internal height of the heating chamber 108 from the base 112 to the open end 110 of the heating chamber 108. It is substantially equal to the length of the side wall 126 of the heating chamber 108 within the heating chamber 108.

When the substrate holder 114 is loaded into the aerosol generating device 100, the user turns on the aerosol generating device 100 using the user actuated button 116. This causes power supply from the power source 120 to the heater 124 through (and controlled by) the control circuit 122. The heater 124 causes heat to be conducted through the protrusions 140 into the aerosol generating substrate 128 to heat the aerosol generating substrate 128 to a temperature at which it can begin to release steam. After heating to a temperature at which steam can begin to be released, the user can inhale this steam by sucking the steam through the second end 136 of the holder 114 of the substrate. Those. vapor is generated from the aerosol-generating substrate 128 located at the first end 134 of the substrate holder 114 in the heating chamber 108 and is drawn along the length of the substrate holder 114 through the vapor collection area 130 in the substrate holder 114 into the second end 136 of the substrate holder, through which it enters user's mouth. This steam flow is shown in Fig. 6 arrow A.

It will be understood that when the user sucks steam in the direction of the arrow A in FIG. 6, steam flows from the region near the aerosol-forming substrate 128 into the heating chamber 108. By this action, ambient air is drawn into the heating chamber 108 (along the flow paths indicated by arrows B in FIG. 6 and shown in more detail in FIG. 6 (a)) from the environment surrounding the aerosol generating device 100.

This ambient air is then heated by the heater 124 and in turn heats the aerosol generating substrate 128 causing the aerosol to be generated. More specifically, in the first embodiment, air enters the heating chamber 108 through a gap provided between the side wall 126 of the heating chamber 108 and the outer layer 132 of the substrate holder 114. To this end, the outside diameter of the substrate holder 114 is smaller than the inside diameter of the heating chamber 108. More specifically, in the first embodiment, the heating chamber 108 has an inside diameter (where no protrusion is provided, such as where or between protrusions 140 are absent) of 10 mm. or less, preferably 8 mm or less, and most preferably about 7.6 mm. This allows the substrate holder 114 to have a diameter of approximately 7.0 mm (±0.1 mm) (when not compressed by the projections 140). This corresponds to an outer circumference of 21 to 22 mm, or more preferably 21.75 mm. In other words, the gap between the substrate holder 114 and the side wall 126 of the heating chamber 108 is most preferably about 0.1 mm. In other embodiments, the gap is at least 0.2 mm, and in some examples up to 0.3 mm. Arrows B in Fig. 6 shows the direction in which air is drawn into the heating

- 18 041326 chamber 108.

When the user activates the aerosol generating device 100 by actuating the user actuated button 116, the aerosol generating device 100 heats the aerosol generating substrate 128 to a temperature sufficient to cause portions of the aerosol generating substrate 128 to evaporate. . In more detail, the control circuit 122 supplies power from the power source 120 to the heater 124 to heat the aerosol-forming substrate 128 to a first temperature. When the aerosol generating substrate 128 reaches the first temperature, the components of the aerosol generating substrate 128 begin to evaporate, i. an aerosol-forming substrate generates steam. After receiving the steam, the user can inhale this steam through the second end 136 of the holder 114 of the substrate. In some scenarios, the user may be aware that it takes a certain amount of time for the aerosol generating device 100 to heat the aerosol generating substrate 128 to a first temperature and start generating steam from the aerosol generating substrate 128. This means that the user can decide when to start inhaling steam. In other scenarios, aerosol generating device 100 is configured to provide an indication to the user that vapor is available for inhalation. Moreover, in the first embodiment, the control circuit 122 causes the button 116 operated by the user to light when the aerosol-forming substrate 128 has the first temperature for an initial period of time. In another embodiment, the indication is provided by another indicator, such as by generating an audible sound or vibration of a vibrating mechanism. Similarly, in other embodiments, the indication is provided after a fixed period of time after activation of the aerosol generating device 100, once the heater 124 has reached operating temperature, or due to some other event.

The user may continue to inhale the vapor as long as the aerosol-generating substrate 128 can continue to generate steam, such as as long as the aerosol-generating substrate 128 has evaporative components left to vaporize to form suitable vapor. The control circuit 122 regulates the power supplied to the heater 124 to ensure that the temperature of the aerosol generating substrate 128 does not exceed a threshold level. In particular, at a certain temperature, which depends on the composition of the aerosol-forming substrate 128, the aerosol-forming substrate 128 will begin to burn. This effect is undesirable and temperatures equal to or above this temperature must be avoided. To facilitate this, the aerosol generating device 100 is provided with a temperature sensor (not shown). The control circuit 122 is configured to receive from a temperature sensor an indication of the temperature of the aerosol-forming substrate 128 and use that indication to control the power supplied to the heater 124. For example, in one scenario, the control circuit 122 applies maximum power to the heater 124 for an initial period of time. until the heater or chamber reaches the first temperature. Then, after the aerosol-forming substrate 128 reaches the first temperature, the control circuit 122 cuts off power to the heater 124 for a second period of time until the aerosol-forming substrate 128 reaches the second temperature below the first temperature. Then, after the heater 124 reaches the second temperature, the control circuit 122 starts to supply power to the heater 124 for a third period of time until the next time the heater 124 reaches the first temperature. This may continue until the aerosol generating substrate 128 is used up (ie, all the aerosol that could have been generated by heating has already been generated) or until the user stops using the aerosol generating device 100. In another scenario, after the first temperature is reached, the control circuit 122 reduces power to the heater 124 to maintain the aerosol generating substrate 128 at the first temperature without increasing the temperature of the aerosol generating substrate 128.

One breath of the user is commonly referred to as a puff. In some scenarios, it is desired to simulate the experience of smoking cigarettes, which means that the aerosol generating device 100 is typically configured to contain enough aerosol generating substrate 128 to provide ten to fifteen puffs.

In some embodiments, the control circuit 122 is configured to count the puffs and turn off the heater 124 after ten to fifteen puffs have been taken by the user. Puff counting is done in one of many different ways. In some embodiments, the control circuit 122 detects when the temperature during a puff decreases as fresh cold air flows past the temperature sensor 170, causing cooling that is detected by the temperature sensor. In other embodiments, air flow is detected directly using a flow sensor. Other suitable methods will be apparent to those skilled in the art. In other embodiments, the control circuit further or alternatively turns off the heater 124 after a predetermined amount of time has elapsed since the first puff. This can help both reduce power consumption and provide a back-up for shutting down in the event of a failure to properly register an account.

- 19 041326 puffs to obtain a predetermined number of puffs.

In some examples, control circuit 122 is configured to power heater 124 to follow a predetermined heating cycle, requiring a predetermined amount of time to complete. Upon completion of this cycle, the heater 124 is completely turned off. In some cases, this loop may use a feedback loop between the heater 124 and the temperature sensor 170. For example, the heating cycle can be parameterized with a series of temperatures to which the heater 124 (or more specifically, the temperature sensor) is heated or allowed to cool. To optimize the temperature of the aerosol-forming substrate 128, the temperatures and duration of such a heating cycle can be determined empirically. This may be necessary because directly measuring the temperature of the aerosol-forming substrate may be impractical or misleading, such as when the outer layer of the aerosol-forming substrate 128 is at a temperature different from that of the core.

In the following example, the time for the first puff is 20 seconds. After this point, the power level supplied to heater 124 decreases from 100% such that the temperature remains constant at approximately 240° C. for a period of approximately 20 seconds. The power supplied to the heater 124 can then be further reduced so that the temperature detected by the temperature sensor 170 is approximately 200°C. This temperature can be maintained for approximately 60 seconds. The power level can then be further reduced so that the temperature sensed by the temperature sensor 170 drops to the operating temperature of the substrate holder 114, which in this case is approximately 180°C. This temperature can be maintained for 140 s. This period of time may be determined by the length of time during which the holder 114 of the substrate can be used. For example, substrate holder 128 may stop producing aerosol after a predetermined amount of time, so a period of time during which the temperature is set to 180°C may allow the heating cycle to continue for that duration. After this point, the power supplied to the heater 124 may be reduced to zero. Even after the heater 124 is turned off, the aerosol or vapor generated while the heater 124 was turned on can still be drawn out of the aerosol generating device 100 when sucked by the user. Therefore, even when the heater 124 is turned off, the user can be alerted to this situation by a visible indicator that remains on despite the fact that the heater 124 has already been turned off in preparation for the end of the aerosol session. In some embodiments, this predetermined period may be 20 seconds. The total length of the heating cycle time in some embodiments may be approximately 4 minutes.

The above exemplary heating cycle can be modified by the user using the substrate holder 114. When the user removes the aerosol from the substrate holder 114, the user's inhalation draws cold air through the open end of the heating chamber 108 towards the base 112 of the heating chamber 108, flowing past the heater 124. The air may then enter the substrate holder 114 through the tip 134 of the substrate holder 114. The entry of cold air into the cavity of the heating chamber 108 reduces the temperature sensed by the temperature sensor 170 as the cold air replaces the hot air that was previously present. When the temperature sensor 170 detects that the temperature has decreased, this can be used to increase the power supplied by the battery to the heater to reheat the temperature sensor 170 to the operating temperature of the substrate holder 114. This can be achieved by applying a maximum amount of power to the heater 124 or, alternatively, by applying a power amount greater than the amount necessary to maintain a steady temperature reading by the temperature sensor 170.

The power source 120 is sufficient to at least bring the aerosol forming substrate 128 in one substrate holder 114 to the first temperature and maintain it at the first temperature to provide sufficient steam for at least ten to fifteen puffs. In general, in accordance with the simulated cigarette smoking experience, the power supply 120 is usually sufficient to repeat this cycle (bringing the aerosol-forming substrate 128 to the first temperature, maintaining the first temperature, and generating steam for ten to fifteen puffs) ten times or even twenty times, thus simulating the user's experience of smoking a pack of cigarettes before the need arises to replace or recharge the power supply 120.

In general, the efficiency of the aerosol generating device 100 is improved when as much of the heat generated by the heater 124 as possible causes the aerosol generating substrate 128 to be heated. To this end, the aerosol generating device 100 is typically configured to controllably supply heat to the aerosol generating substrate 128 while reducing heat flow to other parts of the aerosol generating device 100. In particular, the heat flow to parts of the aerosol generating device 100 controlled by the user is kept to a minimum, whereby these parts remain cool and comfortable to hold,

- 20 041326 example using insulation, as described in more detail in this document.

From FIG. 1-6 and the accompanying description, it is understood that according to the first embodiment, a heating chamber 108 is provided for the aerosol generating device 100, wherein the heating chamber 108 includes an open end 110, a base 112, and a side wall 126 between the open end 110 and the base 112, wherein side wall 126 has a first thickness, and base 112 has a second thickness greater than the first thickness. The reduced thickness of the side wall 126 can help reduce the power consumption of the aerosol generating device 100, as it requires less energy to heat the heating chamber 108 to the required temperature.

Second embodiment.

The second embodiment is described below with reference to FIG. 8. The aerosol generating device 100 according to the second embodiment is identical to the aerosol generating device 100 according to the first embodiment described with reference to FIG. 1-6, except as described below, and like reference numerals are used to refer to like elements. The aerosol generating device 100 according to the second embodiment has an arrangement for allowing air to be drawn into the heating chamber 108 during use, which is different from the arrangement according to the first embodiment.

For more details, with reference to FIG. 8, a channel 113 is provided in the base 112 of the heating chamber 108. The channel 113 is located at the center of the base 112. It extends through the base 112 so that it is in fluid communication with the environment outside the outer shell 102 of the aerosol generating device 100. More specifically, passage 113 is in fluid communication with inlet 137 in outer sheath 102.

The inlet 137 passes through the outer shell 102. It is located at some distance along the length of the outer shell 102 between the first end 104 and the second end 106 of the aerosol generating device 100. In the second embodiment, the outer shell forms a space 139 in the vicinity of the control circuit 122, between the inlet 137 in the outer shell 102 and the channel 113 in the base 112 of the heating chamber 108. The space 139 provides fluid communication between the inlet 137 and the channel 113 so that air can pass from the environment outside the outer shell 102 into the heating chamber 108 through the inlet 137, the space 139 and the channel 113.

In use, as steam is inhaled by the user at the second end 136 of the substrate holder 114, air is drawn into the heating chamber 108 from the environment surrounding the aerosol generating device 100. More specifically, air passes through inlet 139 in the direction of arrow C into space 139. From space 139, air passes through passage 113 in the direction of arrow D into heating chamber 108. This allows steam to be drawn in first, and then steam mixed with air through holder 114 of the substrate in the direction of arrow D for inhalation by the user at the second end 136 of the holder 114 of the substrate. When air enters the heating chamber 108, it usually heats up, and thus the air assists in the transfer of heat to the aerosol-forming substrate 128 by convection.

It will be appreciated that in the second embodiment, the path for air flow through the heating chamber 108 is typically linear, i.e. the path extends from the base 112 of the heating chamber 108 to the open end 110 of the heating chamber 108 in a broadly straight line. The arrangement according to the second embodiment also makes it possible to reduce the gap between the side wall 126 of the heating chamber 108 and the substrate holder. Moreover, in the second embodiment, the diameter of the heating chamber 108 is less than 7.6 mm, and the gap between the substrate holder 114 with a diameter of 7.0 mm and the side wall 126 of the heating chamber 108 is less than 1 mm.

In variations of the second embodiment, the inlet 137 is located differently. In one particular embodiment, inlet 137 is located at first end 104 of aerosol generating device 100. This allows, in a broad sense, air to flow in a straight line through the entire aerosol generating device 100, such as air entering the aerosol generating device 100 at the first end 104, which is typically oriented distally to the user, flowing through the aerosol generating substrate 128 ( e.g., over the substrate, past the substrate, etc.) in and out of the aerosol generating device 100 into the user's mouth at the second end 136 of the substrate holder 114, which during use is typically oriented proximal to the user, such as in the user's mouth.

Third embodiment.

The third embodiment is described below with reference to FIG. 9. The heating chamber 108 according to the third embodiment may be identical to the heating chamber 108 according to the first embodiment described with reference to FIG. 1-6, except as described below, and like reference numerals are used to refer to like elements. It is also possible that the heating chamber 108 according to the third embodiment corresponds to the heating chamber 108 according to the second embodiment, for example with the channel 113 provided in the base 112 of the heating chamber 108, except as described below, and this forms an additional option implementation of the present invention.

However, it should be noted that the heating chamber 108 according to the third (and further) embodiment may itself be a stand-alone embodiment, and may be combined with the features of the fourth to ninth embodiments to achieve the advantages shown below.

In FIG. 9 shows a heating chamber 108 for an aerosol generating device 100. The heating chamber 108 includes a side wall 126 of the chamber and a base 112 of the chamber. The side wall 126 of the chamber and the base 112 of the chamber define the internal volume of the heating chamber 108. The heater 124 is provided in thermal contact with the side wall 126 of the chamber. When power is applied to the heater 124, it heats the side wall 126 of the chamber and the heating chamber 108, and also heats the interior. The internal volume is configured to accommodate the holder 114 of the substrate. The heating chamber 108 is configured to heat air such that the air drawn into the substrate holder 114 heats the aerosol generating substrate 128 of the substrate holder 114 to form an aerosol without burning the substrate holder 114. In FIG. 9 also shows a heat insulating member 152. The heat insulating member 152 includes an insulating side wall 154 and an insulating base 156. The heat insulating member 152 is mounted around a portion of the heating chamber 108, including the chamber base 112. The heat insulating element 152 may encapsulate the heating chamber 108, thus the heating chamber 108 may be located in the interior of the heat insulating element 152. The use of the heat insulating element 152 keeps the heat generated by the heater 124 inside the heating chamber 108. It also ensures that the surrounding space outside the heat insulating element 152 is not exposed to heat. For example, in some embodiments, the outer shell 102 may be located outside the thermal element 152, and the thermal element 152 may reduce the amount of heat transferred to the outer shell 102, so that the user can comfortably hold the outer shell 102.

In FIG. 9 shows that the heat insulating member 152 is composed of an insulating base 156 and an insulating side wall 154, and they can form one sleeve-shaped cavity. Moreover, in some embodiments, as shown in FIG. 9, the insulating side wall 154 and the insulating base 156 may be formed in one piece. This means that the insulating side wall 154 and the insulating base 156 are formed from one continuous web of material rather than separate pieces. This provides the advantage of providing efficient and effective thermal insulation to ensure that most of the heat emitted by the heater 124 is retained in the heating chamber 108.

Heat insulating element 152 may be formed from several materials. For example, the insulating side wall 154 may include a chamber of the insulating side wall containing gas at a pressure below atmospheric pressure. This means that the insulating side wall 154 can be formed with a cavity therein, with the cavity filled with low pressure gas, thus reducing heat flow through the insulating side wall 154. The pressure can be low enough to function as an effective insulator. In one embodiment, the insulating side wall 154 may contain a vacuum. It is an effective insulator and thus minimizes heat loss from the heating chamber 108. In the case where the insulating side wall 152 contains a vacuum, it may be less than 1 mm thick. It may be composed of an outer layer with a thickness of 0.1 mm and an inner layer with a thickness of 0.1 mm, and the thickness of the vacuum located between the outer layer and the inner layer is 0.8 mm.

In one embodiment, the vacuum has a thickness of 0.1 mm, while the insulating side wall 154 has a thickness of 0.3 mm. This may provide a smaller size of the aerosol generating device and hence greater portability for the user.

The insulating base 156 may include a chamber of the insulating base containing gas at a pressure below atmospheric pressure. This means that the insulating base 156 can be formed with a cavity therein, the cavity being filled with low pressure gas, thus reducing heat flow through the insulating base 156. The pressure can be low enough to function as an effective insulator. In one embodiment, the insulating base 156 may contain a vacuum. It is an effective insulator and thus minimizes heat loss from the heating chamber 108. In the case where the insulating base 156 contains a vacuum, it may be less than 1 mm thick. It may be composed of an outer layer with a thickness of 0.1 mm and an inner layer with a thickness of 0.1 mm, and the thickness of the vacuum located between the outer layer and the inner layer is 0.8 mm. In one embodiment, the vacuum is 0.1 mm thick, while the insulating base 156 is 0.3 mm thick. This may provide a smaller size of the aerosol generating device and hence greater portability for the user.

It may be particularly advantageous when the insulating side wall 154 and the insulating

- 22 041326 the base 156 is formed as a one-piece structure so that the heat insulating element 152 is formed with a single vacuum. Thus, this vacuum can pass around the insulating side walls 154 and through the insulating base 156. This can keep heat inside the heating chamber 108. In addition, the formation of the insulating side wall 154 and the insulating base 156 thus prevents any thermal bridging at the junction. between the insulating side wall 154 and the insulating base 156, facilitating conduction of heat around the outer boundary of the composite heat insulating member 152, thereby improving insulating effects by lengthening the path that heat must take to exit the heating chamber 108.

In other embodiments, insulating sidewall 154 and insulating base 156 may be made of or otherwise filled with silicone, cotton, airgel, foam, fibrous material, or glass fiber (or a mixture of two or more of these materials or their equivalents).

The inner wall of the insulating sidewall 154 may be treated to reduce emissivity. For example, the inner wall of the insulating side wall 154 may be covered with a reflective material to reflect radiation emitted from the heating chamber 108 onto the heat insulating element 152 back to the heating chamber 108.

Fourth Embodiment.

The fourth embodiment is described below with reference to FIG. 10. The heating chamber 108 according to the fourth embodiment may be identical to the heating chamber 108 according to the first embodiment described with reference to FIG. 1-6, except as described below, and like reference numerals are used to refer to like elements. It is also possible that the heating chamber 108 according to the fourth embodiment corresponds to the heating chamber 108 according to the second embodiment, for example, with the channel 113 provided in the base 112 of the heating chamber 108, except as described below, and this forms a further embodiment of the present invention.

However, it should be noted that the heating chamber 108 according to the fourth (and further) embodiment may itself be a stand-alone embodiment, and may be combined with the features of the fifth to ninth embodiments to achieve the advantages shown below.

In FIG. 10 shows a configuration similar to that of FIG. 9, with the difference that the insulating side walls 154 and the insulating base 156 are separate elements. The insulating side wall 154 and the insulating base 156 may be connected together, however, in FIG. 10 they are not shown as a one-piece construction. The insulating side wall 154 may, in some embodiments, have a lower thermal conductivity than the insulating base 156. For example, the insulating side wall 154 may contain a vacuum, while the insulating base 156 may contain another insulator. In some embodiments, insulating base 156 may be a flexible element that provides a through passage for electrical connections, such as electrical connections 150 for heating element 164. In some embodiments, insulating base 156 may be made of silicone.

Fifth Embodiment.

The fifth embodiment is described below with reference to FIG. 11. The heating chamber 108 according to the fifth embodiment may be identical to the heating chamber 108 according to the first embodiment described with reference to FIG. 1-6, except as described below, and like reference numerals are used to refer to like elements. It is also possible that the heating chamber 108 according to the fifth embodiment corresponds to the heating chamber 108 according to the second embodiment, for example, with the channel 113 provided in the base 112 of the heating chamber 108, except as described below, and this forms a further embodiment of the present invention.

However, it should be noted that the heating chamber 108 according to the fifth (and further) embodiment may itself be a stand-alone embodiment, and may be combined with the features of the sixth to ninth embodiments to achieve the advantages shown below.

In FIG. 11 shows the heating chamber 108 in thermally conductive engagement with the insulating base 156. The insulating element 152 may be a single piece, or the insulating side wall 154 and the insulating base 156 may be separate elements. In FIG. 11 shows an insulating base 156 comprising a protrusion above the insulating base 156 rising towards the open end of the heat insulating element 152. The protrusion may be formed by deforming the insulating base 156 or may be formed by attaching a portion of additional material to the insulating base 156. Thermal contact between the base 112 of the chamber and the insulating base 152 can ensure that the chamber base 112 does not reach too high a temperature. For example, in some variants

- 23 041326 implementation, it is advantageous to keep the temperature in the base 112 of the chamber lower than in other locations of the heating chamber 108, since this can reduce the likelihood of burning any amount of the substrate 128, which forms an aerosol, placed in the holder 114 of the substrate, when located near the base 112 of the chamber . The use of a protrusion from the insulating base 156 can serve to limit the amount of heat transferred from the chamber base 112 to the insulating base 156, thus keeping the heat inside the heating chamber 108.

Sixth embodiment.

The sixth embodiment is described below with reference to FIG. 12. The heating chamber 108 according to the sixth embodiment may be identical to the heating chamber 108 according to the first embodiment described with reference to FIG. 1-6, except as described below, and like reference numerals are used to refer to like elements. It is also possible that the heating chamber 108 according to the sixth embodiment corresponds to the heating chamber 108 according to the second embodiment, for example, with the channel 113 provided in the base 112 of the heating chamber 108, except as described below, and this forms a further embodiment of the present invention.

However, it should be noted that the heating chamber 108 according to the sixth (and further) embodiment may itself be a stand-alone embodiment, and may be combined with the features of the seventh to ninth embodiments to achieve the advantages shown below.

In FIG. 12 shows the heating chamber 108 in thermally conductive engagement with the insulating base 156 via the chamber base 112 located on top of the insulating base 156. This provides a large contact surface between the chamber base 112 and the insulating base 156. This can be used to increase the amount of heat transferred to the insulating base 156. base 156 to reduce the temperature near chamber base 112 in heating chamber 108. In some embodiments, a small air gap may be present between chamber base 112 and insulating base 156.

Seventh Embodiment.

The seventh embodiment is described below with reference to FIG. 13. The heating chamber 108 according to the seventh embodiment may be identical to the heating chamber 108 according to the first embodiment described with reference to FIG. 1-6, except as described below, and like reference numerals are used to refer to like elements. It is also possible that the heating chamber 108 according to the seventh embodiment corresponds to the heating chamber 108 according to the second embodiment, for example, with the channel 113 provided in the base 112 of the heating chamber 108, except as described below, and this forms a further embodiment of the present invention.

However, it should be noted that the heating chamber 108 according to the seventh (and further) embodiment may itself be a stand-alone embodiment, and may be combined with the features of the eighth to ninth embodiments to achieve the advantages shown below.

In FIG. 13 shows a chamber side wall 126 with a chamber base 112 forming a heating chamber 108 surrounded by an insulating side wall 154 and an insulating base 156, the insulating base 156 being flexible to allow the electrical connections 150 of the heating element 164 to fit around the insulating base 156. The heater 124 may include electrical connections 150 of heating element 164 that extend downward from heater 124. Since power supply 120 is located outside of insulating base 156, electrical connections 150 of heating element 164 must extend from insulating base 156. In the embodiment shown in FIG. 13, insulating base 156 is flexible so that it can be manipulated to create a gap between insulating base 156 and insulating side wall 154 through which electrical connections 150 of heating element 164 can pass. In some embodiments, electrical connections 150 can be located up to connecting together the insulating base 156 and the insulating side walls 154.

Eighth Embodiment.

The eighth embodiment is described below with reference to FIG. 14. The heating chamber 108 according to the eighth embodiment may be identical to the heating chamber 108 according to the first embodiment described with reference to FIG. 1-6, except as described below, and like reference numerals are used to refer to like elements. It is also possible that the heating chamber 108 according to the eighth embodiment corresponds to the heating chamber 108 according to the second embodiment, for example, with the channel 113 provided in the base 112 of the heating chamber 108, except as described below, and this forms a further embodiment of the present invention.

- 24 041326

However, it should be noted that the heating chamber 108 according to the eighth (and further) embodiment may itself be a separate embodiment, and may be combined with the features of the ninth embodiment to achieve the advantages shown below.

In FIG. 14 shows a chamber side wall 126 with a chamber base 112 forming a heating chamber 108 surrounded by an insulating side wall 154 and an insulating base 156, wherein the insulating base 156 includes a space or opening through which the electrical connections 150 of the heating element 164 pass. This embodiment is similar to the embodiment shown in FIG. 13. The main difference is that insulating base 156 contains a space, opening, or cavity through which electrical connections 150 can pass. pass through space.

Ninth Embodiment.

The ninth embodiment is described below with reference to FIG. 15. The heating chamber 108 according to the ninth embodiment may be identical to the heating chamber 108 according to the first embodiment described with reference to FIG. 1-6, except as described below, and like reference numerals are used to refer to like elements. It is also possible that the heating chamber 108 according to the ninth embodiment corresponds to the heating chamber 108 according to the eighth embodiment, i. with the channel 113 provided in the base 112 of the heating chamber 108, except as described below, and this creates a further embodiment of the present invention.

However, it should be noted that the heating chamber 108 according to the ninth (and further) embodiment may itself be an independent embodiment.

In FIG. 15 shows the side wall 126 of the chamber with the base 112 of the chamber, forming a heating chamber 108 surrounded by an insulating side wall 154 and an insulating base 156, while the heating chamber 108 contains a heater 124 with electrical connections 150, and electrical connections 150 pass around the top of the heat insulating element 152 The insulating base 156 in FIG. 15 does not contain a hole. Instead, the electrical connections 150 are bent so that they extend to the open end of the thermal element 152. The electrical connections 150 then extend around the top of the thermal element 150 to reach the power source 120.

Definitions and Alternate Embodiments.

From the above description it is clear that many features of the different embodiments are interchangeable. The present invention extends to additional embodiments, including features from different embodiments, combined with each other in ways that are not specifically mentioned. For example, the third through fifth embodiments do not have the platform 148 shown in FIG. 1-6. The platform 148 may be included in the third through fifth embodiments, thus benefiting from the platform 148 described with respect to these figures.

In FIG. 9-15 show heating chamber 108 and insulation 152, 154, 156 separated from aerosol generating device 100. This is presented to emphasize that the advantageous features described for the configuration of the insulation 152, 154, 156 and the heating chamber 108 are independent of other features of the aerosol inhalation device 100. In particular, the insulation 152, 154, 156 finds many uses, not all of which are associated with the vapor inhalation device 100 described herein. Such designs can take advantage of the improved thermal insulation provided for the thermal insulating element 152. Such applications are advantageously offered in conjunction with the heating chamber described in the document.

The term heater should be understood to mean any device for removing thermal energy sufficient to generate an aerosol from the aerosol-forming substrate 128. The transfer of thermal energy from heater 124 to aerosol forming substrate 128 may be conductive, convective, radiant, or any combination of these methods. As non-limiting examples, conductive heaters may come into direct contact and compress the aerosol generating substrate 128, or may come into contact with a separate component that itself causes the aerosol generating substrate 128 to be heated by conduction, convection, and/or radiation. Convective heating may involve heating a liquid or gas, which then (directly or indirectly) transfers thermal energy to an aerosol-forming substrate.

Radiant heating includes, but is not limited to, transferring energy to the aerosol forming substrate 128 by emitting electromagnetic radiation in the ultraviolet, visible, infrared, microwave, or radio frequency portions of the electromagnetic spectrum. The radiation thus emitted may be absorbed directly by the aerosol forming substrate 128 causing heating, or the radiation may be absorbed by another material such as a detector or fluorescent material.

- 25 041326 material, resulting in re-emission of radiation with a different wavelength or spectral weighting. In some cases, the radiation may be absorbed by the material, which then transfers heat to the aerosol forming substrate 128 by any combination of conduction, convection, and/or radiation.

The heater may be electrically powered, powered by combustion, or by any other suitable means. Electrical heaters may include resistive track elements (optionally containing insulating padding), induction heating systems (eg, containing an electromagnet and a high frequency oscillator), and the like. The heater 128 may be positioned around the outside of the aerosol generating substrate 128, it may partially or completely penetrate the aerosol generating substrate 128, or any combination thereof.

The term temperature sensor is used to describe an element capable of detecting the absolute or relative temperature of a portion of the aerosol generating device 100. It may include thermocouples, thermocouples, thermistors, etc. The temperature sensor may be provided as part of another component, or it may be a separate component. In some examples, more than one temperature sensor may be provided, such as to monitor the heating of various parts of the aerosol generating device 100, such as to determine temperature profiles.

The control circuit 122 has been shown throughout as having a single user actuated button 116 to turn on the aerosol generating device 100. This maintains ease of operation and reduces the chances of misuse by the user of the aerosol generating device 100 or mismanagement of the aerosol generating device 100. In some cases, however, the input controls available to the user may be more complex than indicated, such as controlling the temperature, such as within predetermined limits, such as changing the flavor balance of the steam, or switching between energy saving and fast heating modes.

With reference to the above described embodiments, the aerosol forming substrate 128 comprises tobacco, eg in dried or fermented form, in some cases with additional ingredients to flavor or provide a more uniform or otherwise more pleasant experience. In some examples, aerosol-forming substrate 128, such as tobacco, may be treated with an evaporative agent. The evaporative agent can improve the generation of vapor from the aerosol-forming substrate. The evaporation aid may contain, for example, a polyol such as glycerol or a glycol such as propylene glycol. In some instances, the aerosol forming substrate may not contain tobacco, or even contain no nicotine, but instead may contain natural or artificial ingredients to flavor, volatilize, enhance uniformity, and/or provide other pleasurable effects. The aerosol forming substrate 128 may be provided as a solid or paste type material in cut, briquetted, powdered, granular, strip or sheet form, optionally a combination of these forms. Equally, the aerosol-forming substrate 128 may be a liquid or a gel. Moreover, some examples may contain both solid and liquid/gel portions.

Therefore, the aerosol generating device 100 can equally be called a heated tobacco device, a non-burning tobacco heating device, a tobacco product vaporization device, and the like, and should be interpreted as a device suitable for achieving these effects. The features described herein apply equally to devices configured to vaporize any aerosol-forming substrate.

Embodiments of the aerosol generating device 100 are described as being configured to receive an aerosol generating substrate 128 in a pre-packaged substrate holder 114. The substrate holder 114 may broadly resemble a cigarette and have a tubular region with an aerosol forming substrate suitably positioned. Some designs may also include filters, steam collection areas, cooling areas, and other designs. A layer of paper or other flexible flat material such as foil may also be provided, for example to hold the aerosol generating substrate in place, to further resemble a cigarette, etc.

For the purposes of this document, the term fluid should be construed as generically describing non-solid materials of the type capable of flowing, including, but not limited to, liquids, pastes, gels, powders, and the like. Accordingly, the term fluidized materials should be interpreted as materials that are essentially fluids or have been modified to behave like fluids. Fluidization may include, but is not limited to, pulverization, solvent dissolution, gelation, thickening, dilution, and the like.

As used herein, the term volatile means a substance capable of easily changing from a solid or liquid state to a gaseous state. As a non-limiting example

- 26 041326 the volatile substance may be a substance having a boiling or sublimation temperature near room temperature at atmospheric pressure. Accordingly, the term volatilize or volatilize should be construed to mean making (the material) volatile and/or allowing evaporation or dispersion in the vapor.

For the purposes of this document, the term vapor (or vapor) means: (i) the form into which liquids naturally convert when subjected to a sufficient degree of heat; or (ii) liquid/moisture particles suspended in the atmosphere and visible as vapor/smoke clouds; or (iii) a fluid that fills the volume like a gas, but having a temperature below its critical temperature, can be turned into a liquid under pressure alone.

In accordance with this definition, the term to vaporize (or convert to vapor) means: (i) to change or cause a change in vapor; and (ii) change the physical state of the particles (ie, from a liquid or solid to a gaseous state).

As used herein, the term pulverize (or convert to dust) means: (i) converting (a substance, in particular a liquid) into very small particles or droplets; and (ii) keep the particles in the same physical state (liquid or solid) as before spraying.

As used herein, the term aerosol means a system of particles dispersed in air or a gas such as fog, haze or smoke. Accordingly, the term aerosolize (or aerosolize) means to aerosolize and/or disperse as an aerosol. It should be noted that the meaning of the term aerosol/form aerosol is consistent with each of the terms defined above to volatilize, atomize, and vaporize. For the avoidance of doubt, the term aerosol is used to generically describe mist or droplets containing pulverized, volatilized or vaporized particles. The term aerosol also includes mist or droplets containing any combination of atomized, volatilized or vaporized particles.

Claims (14)

1. Heating chamber (108) for an aerosol generating device (100), wherein the heating chamber (108) comprises a side wall (126) of the chamber; the base (112) of the chamber, while the side wall (126) of the chamber and the base (112) of the chamber together form the internal volume of the heating chamber (108); a heater (124) attached to the outer surface of the heating chamber (108) in thermal contact with the side wall (126) of the chamber; and a heat-insulating element (152) containing an insulating side wall (154) and an insulating base (156), wherein the heat-insulating element (152) is designed in such a way that the part of the heating chamber (108) containing the base (112) of the chamber is inserted inside the heat-insulating element (152), and the heater (124) passes around the side wall (126) of the chamber, but does not pass around the base (112) of the chamber, while the base (112) of the chamber is at a distance from the insulating base (156). 2. Heating chamber (108) according to claim 1, characterized in that the insulating side wall (154) has a lower thermal conductivity than the insulating base (156). 3. Heating chamber (108) according to claim 1 or 2, characterized in that the heat insulating element (152) is in the form of a sleeve with a hollow interior and an open top. 4. Heating chamber (108) according to any of the preceding claims, characterized in that at least one of the insulating side wall (154) and the insulating base (156) respectively contains an insulating side wall chamber and/or an insulating base chamber containing gas under pressure below atmospheric pressure. 5. Heating chamber (108) according to claim 4, characterized in that at least one of the insulating side wall chamber and the insulating base chamber contains a vacuum. 6. Heating chamber (108) according to any one of the preceding claims, characterized in that the insulating base (156) is a flexible element providing a through passage for the electrical connectors (150). 7. Heating chamber (108) according to claim 6, characterized in that the flexible element is made of silicone. 8. Heating chamber (108) according to any one of claims 3 to 7, characterized in that the insulating base (156) and the insulating side wall (154) form one sleeve-shaped cavity. 9. Heating chamber (108) according to any one of the preceding claims, characterized in that the heater (124) contains electrical connections (150) for receiving power and the electrical connections (150) pass through the insulating base (156). 10. Heating chamber (108) according to any one of the preceding claims, characterized in that the heater (124) contains electrical connections (150) for receiving power and electrical connections (150) extend around the top of the insulating side wall (154). - 27 041326 11. Heating chamber (108) according to any one of the preceding claims, characterized in that the inner surface of the insulating side wall (140) is treated to reduce emissivity. 12. Device (100), generating an aerosol, containing a source (120) of power supply; outer shell (102); a heating chamber (108) according to any one of claims 1 to 11, located inside the outer shell (102); and a control circuit (122) configured to control the supply of power from the power source (120) to the heater (124). 13. An aerosol generating device (100) according to claim 12, characterized in that it further comprises an elastically deformable element (160) between the outwardly facing surface of the insulating side wall (154) and the outer shell (102) for holding the heat-insulating element (152) on place. 14. An aerosol generating device (100) according to claim 13, characterized in that the heat insulating element (152) is supported by spacers extending between the heat insulating element (152) and the outer shell (102).