Patent Description:
Devices which heat, rather than burn, an aerosol generating material to produce an aerosol for inhalation have become popular with consumers in recent years.

Such devices can use one of a number of different approaches to provide heat to the aerosol generating material. One such approach is to provide an aerosol generating device which employs an induction heating system and into which an aerosol generating article, comprising aerosol generating material, can be removably inserted by a user. In such a device, an induction coil is provided with the device and an induction heatable susceptor is provided with the aerosol generating article. Electrical energy is provided to the induction coil when a user activates the device which in turn generates an alternating electromagnetic field. The susceptor couples with the electromagnetic field and generates heat which is transferred, for example by conduction, to the aerosol generating material and an aerosol is generated as the aerosol generating material is heated.

The characteristics of the aerosol generated by the aerosol generating device are dependent upon a number of factors, including the construction of the aerosol generating article used with the aerosol generating device. There is, therefore, a desire to provide an aerosol generating article which is easy to manufacture and which enables the characteristics of the aerosol generated during use of the article to be optimised.

According to a first aspect of the present disclosure, there is provided an aerosol generating article as set out in claim <NUM>.

According to a second aspect of the present disclosure, there is provided a method for manufacturing an aerosol generating article as set out in claim <NUM>.

The aerosol generating article is for use with an aerosol generating device for heating the aerosol generating material, without burning the aerosol generating material, to volatise at least one component of the aerosol generating material and thereby generate a vapour or aerosol for inhalation by a user of the aerosol generating device.

In general terms, a vapour is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapour can be condensed to a liquid by increasing its pressure without reducing the temperature, whereas an aerosol is a suspension of fine solid particles or liquid droplets, in air or another gas. It should, however, be noted that the terms 'aerosol' and 'vapour' may be used interchangeably in this specification, particularly with regard to the form of the inhalable medium that is generated for inhalation by a user.

The aerosol generating article is easy to manufacture because the inductively heatable susceptor can be inserted easily into the first region.

The aerosol generating material may have a first end and a second end and may have an intermediate point between the first and second ends.

In one embodiment, the first region may be located upstream of the second region relative to an aerosol flow direction within the article. By providing an inductively heatable susceptor exclusively in the upstream first region, the aerosol generating material in the first region is heated by the heat generated by the inductively heatable susceptor to generate an aerosol. The aerosol then flows through the aerosol generating material in the second region, downstream of the first region, which helps it to cool and condense to form a vapour or aerosol suitable for inhalation by a user of the aerosol generating device. As the aerosol flows through the second region, the flavour characteristics of the aerosol are also enhanced by the aerosol generating material in the second region, thereby ensuring that the characteristics of the aerosol or vapour generated during use of the article are optimised.

The first region may extend from the first end to the intermediate point and the second region may extend from the intermediate point to the second end. The inductively heatable susceptor may include an elongate part which extends from the first end to the intermediate point. With this arrangement, the inductively heatable susceptor extends fully through the first region ensuring that the aerosol generating material in the first region is heated in the most effective manner by heat transferred from the inductively heatable susceptor.

In another embodiment, the first region may be located downstream of the second region relative to an aerosol flow direction within the article. By providing an inductively heatable susceptor exclusively in the downstream first region, the aerosol generating material in the first region is heated by the heat generated by the inductively heatable susceptor to generate an aerosol. As air flows through the upstream second region, flavour compounds may be released from the aerosol generating material in the second region and entrained in the air before the air flows through the downstream first region, thereby enhancing the characteristics of the aerosol or vapour generated during use of the article. The aerosol generating article also has an improved appearance because the inductively heatable susceptor is not positioned in the upstream second region and, therefore, is not visible from the first end. Positioning the inductively heatable susceptor in the downstream first region also ensures that the inductively heatable susceptor cannot be released from the aerosol generating material, for example by dropping out of the first end.

The first region may extend from the second end to the intermediate point and the second region may extend from the intermediate point to the first end. The inductively heatable susceptor may include an elongate part which extends from the second end to the intermediate point. With this arrangement, the inductively heatable susceptor extends fully through the first region ensuring that the aerosol generating material in the first region is heated in the most effective manner by heat transferred from the inductively heatable susceptor.

The inductively heatable susceptor may extend in a direction substantially parallel to a longitudinal direction of the aerosol generating article. With this arrangement, air flow resistance through the aerosol generating article is minimised.

The inductively heatable susceptor is tubular. The use of a tubular susceptor ensures that heat is generated effectively in the first region because the tubular shape of the susceptor provides a closed circular electrical path which is suitable for generating eddy currents.

The wall thickness of tubular inductively heatable susceptor may be between <NUM> and <NUM>, may typically be between <NUM> and <NUM> and may more typically be between <NUM> and <NUM>. In one example, the wall thickness may be approximately <NUM>. A wall thickness within these ranges facilitates insertion of the tubular inductively heatable susceptor into the first region of the aerosol generating material. For example, if the wall thickness is too low, the tubular inductively heatable susceptor may be deformed during insertion into the aerosol generating material. If, on the other hand, the wall thickness is too great, insertion of the tubular inductively heatable susceptor may be difficult and the aerosol generating material may be deformed or displaced. In addition, a wall thickness within these ranges ensures that that the tubular inductively heatable susceptor is heated quickly during use of the aerosol generating article in an aerosol generating device.

The tubular inductively heatable susceptor may be continuous in the circumferential direction and may not have a longitudinally extending joint or seam. The tubular inductively heatable susceptor thus has a uniform electrical resistance.

The aerosol generating material in the first region is positioned both inside and outside of the tubular inductively heatable susceptor. With this arrangement, heat from the tubular inductively heatable susceptor is transferred to the aerosol generating material positioned both inside and outside of the tubular susceptor, thereby optimising aerosol generation and improving energy efficiency as the susceptor is surrounded by the aerosol generating material.

The inductively heatable susceptor may include a sharpened or pointed end and may possibly include a plurality of sharpened or pointed ends. The or each sharpened or pointed end may be positioned at the intermediate point of the aerosol generating material. The provision of an inductively heatable susceptor with a sharpened or pointed end allows the inductively heatable susceptor to be easily positioned in the aerosol generating material, for example by being inserted into the aerosol generating material from the first end or the second end, during manufacture of the aerosol generating article.

In some embodiments, the sharpened or pointed end may have a surface area of less than <NUM><NUM>. The surface area could be less than <NUM><NUM> and is typically less than <NUM><NUM>. A small surface area facilitates insertion of the inductively heatable susceptor into the aerosol generating material during manufacture of the aerosol generating article.

The inductively heatable susceptor may be connected to a sharpened or pointed part comprising a non-inductively heatable material. The non-inductively heatable material may comprise a material which is substantially non-electrically conductive and non-magnetically permeable. With this arrangement, it will be understood that heat is not generated in the sharpened or pointed part. The ease of manufacture of the sharpened or pointed part may be improved due to the use of a non-inductively heatable material, for example a plastics material or a ceramic material which is resistant to high temperatures.

In one embodiment, the inductively heatable susceptor may be connected at one end to a sharpened or pointed part comprising a non-inductively heatable material.

In another embodiment, the sharpened or pointed part may include a connector, such as a tubular connector, and the inductively heatable susceptor may be connected to the connector. The provision of a connector may facilitate connection of the sharpened or pointed part and the inductively heatable susceptor.

In a first example, a tubular inductively heatable susceptor may be positioned around a tubular connector and may form a sleeve which surrounds, and is connected to, the tubular connector. This arrangement may allow the sharpened or pointed end and the inductively heatable susceptor to be connected with relative ease.

In a second example, the inductively heatable susceptor may comprise a coating of inductively heatable material applied to the connector.

The aerosol generating material may comprise an aerosol generating sheet which may be substantially parallel to a longitudinal axis of the aerosol generating article. This arrangement may facilitate insertion of the inductively heatable susceptor into the aerosol generating material from the first end in embodiments in which the first region is upstream of the second region or from the second end in embodiments in which the first region is downstream of the second region and/or may facilitate air flow through the aerosol generating material during use of the aerosol generating article in an aerosol generating device.

In an embodiment, for example in which the first region is located upstream of the second region, a distance between the intermediate point and the second end may be between <NUM>% and <NUM>% of a distance between the first and second ends. The distance between the intermediate point and the second end may be between <NUM>% and <NUM>% of the distance between the first and second ends. The distance between the intermediate point and the second end may be between <NUM>% and <NUM>% of the distance between the first and second ends. The distance between the intermediate point and the second end may be <NUM>% of the distance between the first and second ends. Thus, the intermediate point may be located at a midpoint between the first and second ends. This arrangement provides a good balance between the function of the aerosol generating material in the first and second regions and ensures that the characteristics of the resulting aerosol generated during use of the aerosol generating article are optimised.

The inductively heatable susceptor may have a length which may be greater than a width of the aerosol generating article. The resulting aerosol generating article may have a shape that is optimised for insertion into a cavity of an aerosol generating device.

The aerosol generating material may be wrapped by a sheet of material. The sheet of material thus acts as a wrapper. The wrapper may comprise a material which is substantially non-electrically conductive and non-magnetically permeable and may, for example, comprise a paper wrapper. The use of a wrapper may facilitate manufacture and handing of the aerosol generating article and may enhance aerosol generation.

The aerosol generating article may include an air-permeable member at the first end of the aerosol generating material. The aerosol generating article may include an air-permeable member at the second end of the aerosol generating material. The air-permeable member may be an air-permeable cap. The air-permeable member may be a filter, for example comprising cellulose acetate fibres.

In embodiments in which the first region is positioned upstream of the second region, the aerosol generating article may include an air-permeable member, for example an air-permeable cap, at the first end of the aerosol generating material. The aerosol generating material visible at the first end may be subjected to a small amount of deformation due to insertion of the inductively heatable susceptor into the first region, and the air-permeable member may help to improve the appearance of the aerosol generating article by covering the first end and ensuring that the aerosol generating material in the first region is not exposed or visible. The air-permeable member may also help to ensure that the inductively heatable susceptor is not released from the first region of the aerosol generating material by dropping out of the first end.

The air-permeable member may include an aperture, for example a slit or a hole, for receiving a temperature sensor. The aperture allows a temperature sensor of an aerosol generating device to be positioned in, and possibly to extend through, the air-permeable member and to be positioned in close proximity to the inductively heatable susceptor. This in turn ensures that the temperature of the inductively heatable susceptor can be accurately detected by the temperature sensor and that the control of the aerosol generating device can be optimised.

The aperture may have dimensions which are the same as, or less than, the dimensions of the temperature sensor. For example, in embodiments in which the aperture is a hole, the hole may have an inner diameter which is the same as, or less than, an outer diameter of the temperature sensor. With this arrangement, the temperature sensor may advantageously be cleaned during insertion of the temperature sensor into the aperture (as the aerosol generating article is inserted into an aerosol generating device) and/or during removal of the temperature sensor from the aperture (as the aerosol generating article is removed from an aerosol generating device).

In embodiments in which the first region is positioned upstream of the second region, the air-permeable member may be in abutting co-axial alignment with the first region of the aerosol generating material.

In embodiments in which the first region is positioned upstream of the second region, the air-permeable member may be in co-axial alignment with, and spaced from, the first region of the aerosol generating material. The air-permeable member may be spaced from the first region of the aerosol generating material by a gap, for example created by a hollow tubular member which may be positioned between the first end and the air-permeable member. The spacing between the air-permeable member and the first region of the aerosol generating material provided by the gap increases the distance between the air-permeable member and the inductively heatable susceptor positioned in the first region. This in turn reduces the likelihood of damage to the air-permeable member due to heat transfer from the inductively heatable susceptor. The spacing provided by the gap may also help to trap any condensed vapour or aerosol emitted from the first end during heating of the aerosol generating material in the first region, thereby minimising or eliminating the release of the condensed vapour or aerosol from the first end.

The aperture in the air-permeable member and/or the length of the air-permeable member may be dimensioned so that a temperature sensor of an aerosol generating device extends through the air-permeable member and into the gap, for example into the hollow tubular member, between the air-permeable member and the first region of the aerosol generating material. With this arrangement, the temperature sensor can be positioned in close proximity to the inductively heatable susceptor, thereby ensuring that the temperature of the inductively heatable susceptor can be accurately detected by the temperature sensor and that the control of the aerosol generating device can be optimised. In addition, the temperature sensor can be cleaned more effectively by the air-permeable member during insertion of the temperature sensor into the aperture (as the aerosol generating article is inserted into an aerosol generating device) and/or during removal of the temperature sensor from the aperture (as the aerosol generating article is removed from an aerosol generating device).

In one embodiment of the method according to the second aspect, the first region may be located upstream of the second region, the first region may extend from a first end of the aerosol generating material to an intermediate point between the first end and a second end of the aerosol generating material, the second region may extend from the intermediate point to the second end, and the inductively heatable susceptor is tubular. In this case, the method may comprise inserting the tubular inductively heatable susceptor into the first region from the first end so that it extends from the first end to the intermediate point.

In another embodiment of the method according to the second aspect, the first region may be located downstream of the second region, the first region may extend from a second end of the aerosol generating material to an intermediate point between the second end and a first end of the aerosol generating material, the second region may extend from the intermediate point to the first end, and the inductively heatable susceptor is tubular. In this case, the method may comprise inserting the tubular inductively heatable susceptor into the first region from the second end so that it extends from the second end to the intermediate point.

The method comprises inserting the tubular inductively heatable susceptor into the first region so that the aerosol generating material is positioned both inside and outside of the tubular inductively heatable susceptor. As explained above, this arrangement ensures that heat from the tubular inductively heatable susceptor is transferred to the aerosol generating material positioned both inside and outside of the tubular inductively heatable susceptor, thereby optimising aerosol generation and maximising energy efficiency.

The method may comprise inserting the tubular inductively heatable susceptor into the first region by a pusher. The pusher may have a tapered part, for example a tapered end, which can be partially inserted into an end of the tubular inductively heatable susceptor. The tapered part may have an external diameter which corresponds to an internal diameter of the tubular inductively heatable susceptor. Correct insertion of the tubular inductively heatable susceptor into the first region is thereby assured by the pusher.

The method may comprise inserting the inductively heatable susceptor into the first region from the first end or the second end so that it extends to the intermediate point and may comprise supporting the aerosol generating material at the opposite one of the first and second ends during insertion of the inductively heatable susceptor into the first region. In embodiments in which the first region is located upstream of the second region, the method may comprise inserting the inductively heatable susceptor into the first region from the first end so that it extends from the first end to the intermediate point and supporting the aerosol generating material at the second end during insertion of the inductively heatable susceptor into the first region. In embodiments in which the first region is located downstream of the second region, the method may comprise inserting the inductively heatable susceptor into the first region from the second end so that it extends from the second end to the intermediate point and supporting the aerosol generating material at the first end during insertion of the inductively heatable susceptor into the first region.

The aerosol generating material may be supported at the first end or the second end by a support member. Supporting the aerosol generating material during insertion of the inductively heatable susceptor, for example by the support member, may ensure that the aerosol generating material is adequately supported and not displaced by the inductively heatable susceptor as it is inserted into the aerosol generating material.

The support member may be an external support member, for example part of a manufacturing apparatus. The method may comprise supporting the aerosol generating material at the first end or the second end by the external support member and may comprise inserting the inductively heatable susceptor into the first region from the first end or the second end prior to assembling the aerosol generating material with other component parts of the aerosol generating article. With this arrangement, the first end or the second end of the aerosol generating material is supported directly by the external support member. This allows other component parts of the aerosol generating article, such as a filter, to be combined with the aerosol generating material after insertion of the inductively heatable susceptor into the first region, thereby allowing greater freedom in the design and construction of the aerosol generating article.

The support member may be an integral support member provided by a component part of the aerosol generating article, for example a filter. The method may comprise inserting the inductively heatable susceptor into the first region from the first end or the second end after assembling the aerosol generating material and the component part intended as the integral support member. With this arrangement, the aerosol generating material is supported at the first end or the second end by the integral support member during insertion of the inductively heatable susceptor into the first region from the opposite one of the first end or the second end. The manufacturing apparatus and method can be simplified because the need for an external support member is avoided.

The aerosol generating material in the second region, i.e. between the intermediate point and the other of the first and second ends from which the inductively heatable susceptor is not inserted, may be compressed in a direction perpendicular to an axis of the aerosol generating material or a direction of the insertion during insertion of the inductively heatable susceptor into the first region. The act of compressing the aerosol generating material in the second region during insertion of the inductively heatable susceptor into the first region ensures that the aerosol generating material is adequately supported and not displaced during insertion of the inductively heatable susceptor.

The method may comprise positioning the aerosol generating material in a receiving portion formed around an outer surface of a drum. The receiving portion may have a first receiving section that does not compress the aerosol generating material in the first region and may have a second receiving section that compresses the aerosol generating material in the second region. The method may comprise supporting the aerosol generating material in the receiving portion by a support drum. The use of a drum having first (non-compression) and second (compression) receiving sections, in combination with an optional support drum, provides a convenient way to compress the aerosol generating material in the second region.

The method may comprise wrapping a sheet of material around the aerosol generating material.

In embodiments in which the first region is located downstream of the second region, the method may comprise positioning a filter at the second end in coaxial alignment with the aerosol generating material and after insertion of the inductively heatable susceptor into the first region of the aerosol generating material from the second end. The method may further comprise positioning a hollow tubular member between the second end and the filter. The hollow tubular member may advantageously allow the heated vapour or aerosol from the first region to cool and condense before it is inhaled by a user through the filter during use of the aerosol generating article in an aerosol generating device.

The method may further comprise wrapping a sheet of material around the aerosol generating material, the filter and the optional hollow tubular member. This ensures that the component parts of the aerosol generating article are retained in the correct positional relationship.

According to a third aspect of the present disclosure, there is provided an aerosol generating system comprising:.

By positioning the aerosol generating article in the cavity so that the longitudinal axis of the inductively heatable susceptor, i.e. the tubular inductively heatable susceptor, is substantially aligned with the longitudinal axis of the cavity, the positional relationship between the inductively heatable susceptor and the induction coil is optimised thereby providing for optimum coupling of the electromagnetic field with the inductively heatable susceptor and, thus, optimum heating of the inductively heatable susceptor during operation of the aerosol generating device.

The inductively heatable susceptor may comprise one or more, but not limited, of aluminium, iron, nickel, stainless steel and alloys thereof, e.g. Nickel Chromium or Nickel Copper. With the application of an electromagnetic field in its vicinity, the susceptor may generate heat due to eddy currents and magnetic hysteresis losses resulting in a conversion of energy from electromagnetic to heat.

The induction coil may comprise a Litz wire or a Litz cable. It will, however, be understood that other materials could be used. The induction coil may be substantially helical in shape and may, for example, extend around the cavity in which the aerosol generating article is positioned.

The circular cross-section of a helical induction coil may facilitate the insertion of the aerosol generating article into the aerosol generating device, for example into the cavity in which the aerosol generating article is received in use, and may ensure uniform heating of the aerosol generating material.

The induction coil may be arranged to operate in use with a fluctuating electromagnetic field having a magnetic flux density of between approximately 20mT and approximately <NUM>. 0T at the point of highest concentration.

The aerosol generating device may include a power source and circuitry which may be configured to operate at a high frequency. The power source and circuitry may be configured to operate at a frequency of between approximately <NUM> and <NUM>, possibly between approximately <NUM> and <NUM>, and possibly at approximately <NUM>. The power source and circuitry could be configured to operate at a higher frequency, for example in the MHz range, depending on the type of inductively heatable susceptor that is used.

The aerosol generating material may be any type of solid or semi-solid material. Example types of aerosol generating material include powder, granules, particles, gel, strips, loose leaves, cut filler, pellets, powder, shreds, strands, foam material and sheets. The aerosol generating material may comprise plant derived material and in particular, may comprise tobacco.

The aerosol generating material may comprise an aerosol-former. Examples of aerosol-formers include polyhydric alcohols and mixtures thereof such as glycerine or propylene glycol. Typically, the aerosol generating material may comprise an aerosol-former content of between approximately <NUM>% and approximately <NUM>% on a dry weight basis. In some embodiments, the aerosol generating material may comprise an aerosol-former content of approximately <NUM>% on a dry weight basis.

Referring initially to <FIG>, there is shown a first example of an aerosol generating article <NUM> for use with an aerosol generating device, an example of which will be described later in this specification. The aerosol generating article <NUM> is elongate and substantially cylindrical. The circular cross-section facilitates handling of the article <NUM> by a user and insertion of the article <NUM> into a cavity of an aerosol generating device.

The article <NUM> comprises aerosol generating material <NUM> having a first region <NUM> and a second region <NUM>. The first region <NUM> is located upstream of the second region <NUM> relative to an aerosol flow direction within the article <NUM>. The aerosol generating material <NUM> has a first end <NUM>, a second end <NUM> and an intermediate point <NUM> between the first and second ends <NUM>, <NUM>. In the illustrated embodiment, the intermediate point <NUM> is located at a midpoint between the first and second ends <NUM>, <NUM>, so that the first and second regions <NUM>, <NUM> have the same longitudinal dimension. The intermediate point <NUM> could, however, be located at other positions between the first and second ends <NUM>, <NUM> as explained earlier in this specification.

The article <NUM> comprises a filter <NUM>, for example comprising cellulose acetate fibres, located downstream of the second region <NUM> and through which a user can inhale an aerosol or vapour generated during use of the article <NUM> in an aerosol generating device. The aerosol generating material <NUM> and the filter <NUM> are wrapped by a sheet of material, for example a paper wrapper <NUM>, to maintain the positional relationship between the first and second regions <NUM>, <NUM> of the aerosol generating material <NUM> and the filter <NUM>.

The article <NUM> comprises an inductively heatable susceptor <NUM> which is positioned in the first region <NUM>. The inductively heatable susceptor <NUM> is substantially U-shaped, comprising two elongate parts 22a, 22b, which extend through the first region <NUM> from the first end <NUM> to the intermediate point <NUM>, and a connecting part <NUM> which connects the two elongate parts 22a, 22b.

The ends of the elongate parts 22a, 22b can be sharpened or pointed to facilitate insertion of the inductively heatable susceptor <NUM> into the first region <NUM> from the first end <NUM>. The connecting part <NUM> constitutes a flat part <NUM> which allows the inductively heatable susceptor <NUM> to be easily manipulated and inserted into the first region <NUM> from the first end <NUM>, for example in the correct orientation. In the illustrated example, the end of the inductively heatable susceptor <NUM>, constituted by the flat part <NUM>, is flush with the first end <NUM> of the aerosol generating material <NUM> but it will be appreciated that in other embodiments the end of the inductively heatable susceptor <NUM> constituted by the flat part <NUM> could be embedded in the first end <NUM> so that the inductively heatable susceptor <NUM> is fully surrounded by the aerosol generating material <NUM> in the first region <NUM>.

The aerosol generating material <NUM> is typically a solid or semi-solid material. Examples of suitable aerosol forming solids include powder, granules, particles, gel, strips, loose leaves, cut filler, pellets, powder, shreds, strands, foam material and sheets. The aerosol generating material <NUM> typically comprises plant derived material and, in particular, comprises tobacco.

The aerosol generating material <NUM> comprises an aerosol-former such as glycerine or propylene glycol. Typically, the aerosol generating material may comprise an aerosol-former content of between approximately <NUM>% and approximately <NUM>% on a dry weight basis. Upon heating, the aerosol generating material <NUM> releases volatile compounds possibly including nicotine or flavour compounds such as tobacco flavouring.

When a time varying electromagnetic field is applied in the vicinity of the inductively heatable susceptor <NUM> during use of the article <NUM> in an aerosol generating device, heat is generated in the inductively heatable susceptor <NUM> due to eddy currents and magnetic hysteresis losses and the heat is transferred from the inductively heatable susceptor <NUM> to the aerosol generating material <NUM> in the first region <NUM> to heat the aerosol generating material <NUM> in the first region <NUM> without burning it and to thereby generate an aerosol. As a user inhales through the filter <NUM>, the aerosol is drawn in a downstream direction through the article <NUM> from the first region <NUM> and through the second region <NUM>. As the aerosol flows through the second region <NUM> towards the filter <NUM>, the aerosol generating material <NUM> in the second region <NUM> causes the aerosol to cool and condense to form an aerosol or vapour with suitable characteristics for inhalation by a user through the filter <NUM>. At the same time, one or more volatile components may also be released from the aerosol generating material <NUM> in the second region <NUM> due to heating of the aerosol generating material <NUM> in the second region <NUM> by the heated aerosol flowing through the second region <NUM>, thereby enhancing the characteristics (e.g. flavour) of the vapour or aerosol that is delivered to a user through the filter <NUM>.

Referring now to <FIG>, there is shown a second example of an aerosol generating article <NUM> which is similar to the aerosol generating article <NUM> illustrated in <FIG> and in which corresponding elements are designated using the same reference numerals.

The aerosol generating article <NUM> is identical to the aerosol generating article <NUM> illustrated in <FIG> in all respects except that the inductively heatable susceptor <NUM> is substantially E-shaped, comprising three elongate parts 22a, 22b, 22c which extend through the first region <NUM> from the first end <NUM> to the intermediate point <NUM>. The three elongate parts 22a, 22b, 22c are connected by a connecting part <NUM>.

As discussed above, the ends of the elongate parts 22a, 22b, 22c can be sharpened or pointed to facilitate insertion of the inductively heatable susceptor <NUM> into the first region <NUM> from the first end <NUM>. The connecting part <NUM> again constitutes a flat part <NUM> which allows the inductively heatable susceptor <NUM> to be easily manipulated and inserted into the first region <NUM> from the first end <NUM>.

Referring now to <FIG>, there is shown a third example of an aerosol generating article <NUM> which is similar to the aerosol generating article <NUM> illustrated in <FIG> and in which corresponding elements are designated using the same reference numerals.

The aerosol generating article <NUM> is identical to the aerosol generating article <NUM> illustrated in <FIG> in all respects except that the inductively heatable susceptor <NUM> is substantially I-shaped, comprising a single elongate part <NUM> which extends through the first region <NUM> from the first end <NUM> to the intermediate point <NUM>. As best seen in <FIG>, the inductively heatable susceptor <NUM> is positioned in the first region <NUM> at the centre of the aerosol generating material <NUM> to ensure that the aerosol generating material <NUM> in the first region <NUM> is uniformly heated.

Referring now to <FIG>, there is shown a fourth example of an aerosol generating article <NUM> which is similar to the aerosol generating article <NUM> illustrated in <FIG> and in which corresponding elements are designated using the same reference numerals.

The aerosol generating article <NUM> is identical to the aerosol generating article <NUM> illustrated in <FIG> in all respects except that the inductively heatable susceptor <NUM> is tubular. The aerosol generating material <NUM> in the first region <NUM> is positioned both inside and outside of the tubular inductively heatable susceptor <NUM> to maximise heat transfer to the aerosol generating material <NUM> in the first region <NUM> and to thereby maximise the amount of aerosol that is generated and to maximise energy efficiency.

In preferred embodiments, the tubular induction heatable susceptor <NUM> and the paper wrapper <NUM> are concentric, thereby ensuring that the aerosol generating material <NUM> in the first region <NUM> is uniformly heated.

In order to facilitate insertion of the tubular inductively heatable susceptor <NUM> into the aerosol generating material <NUM> from the first end <NUM>, the tubular inductively heatable susceptor <NUM> can comprise a sharpened or pointed end <NUM>, as shown in <FIG>, which is positioned at the intermediate point <NUM> following insertion of the inductively heatable susceptor <NUM> into the first region <NUM>. By way of example, the sharpened or pointed end <NUM> can be created by providing a bevel cut at an end of the tubular inductively heatable susceptor <NUM>.

Referring now to <FIG>, and in a variation of the example illustrated in <FIG>, the tubular inductively heatable susceptor <NUM> can be connected at one end to a sharpened or pointed part <NUM> comprising a non-inductively heatable material, for example a plastics material such as polyether ether ketone (PEEK). The ends of the tubular inductively heatable susceptor <NUM> and the sharpened or pointed part <NUM> typically have the same outer diameter as illustrated in <FIG> and can be connected in any suitable manner. The sharpened or pointed part <NUM> facilitates insertion of the tubular inductively heatable susceptor <NUM> into the aerosol generating material <NUM> from the first end <NUM> and is positioned at the intermediate point <NUM> following insertion of the inductively heatable susceptor into the first region <NUM>. The sharpened or pointed part <NUM> can be easily manufactured, for example by a suitable moulding or extrusion process, potentially avoiding the need to bevel cut the component to provide the sharpened or pointed end.

Referring now to <FIG>, and in a variation of the example illustrated in <FIG>, the tubular inductively heatable susceptor <NUM> can again be connected to a sharpened or pointed part <NUM> comprising a non-inductively heatable material, for example a plastics material such as polyether ether ketone (PEEK). In this example, the sharpened or pointed part <NUM> includes a tubular connector <NUM> to which the inductively heatable susceptor <NUM> is connected. The tubular connector <NUM> has a smaller outer diameter than the inner diameter of the tubular inductively heatable susceptor <NUM> so that the tubular connector <NUM> can be inserted into the end of the tubular inductively heatable susceptor <NUM> as shown in <FIG>. Thus, the end of the tubular inductively heatable susceptor <NUM> forms a sleeve which surrounds, and is connected to, the tubular connector <NUM>. The outer diameter of the sharpened or pointed part <NUM> where it abuts the end of the tubular inductively heatable susceptor <NUM> corresponds to the outer diameter of the tubular inductively heatable susceptor <NUM> to provide a smooth surface which facilitates insertion of the tubular inductively heatable susceptor <NUM> into the aerosol generating material <NUM> from the first end <NUM>.

Referring now to <FIG>, there is shown an aerosol generating system <NUM> for generating an aerosol to be inhaled. The aerosol generating system <NUM> comprises an aerosol generating device <NUM> comprising a housing <NUM>, a power source <NUM> and control circuitry <NUM> which may be configured to operate at high frequency. The power source <NUM> typically comprises one or more batteries which could, for example, be inductively rechargeable. The aerosol generating device <NUM> also includes one or more air inlets, for example two air inlets 50a, 50b.

The aerosol generating device <NUM> comprises an induction heating assembly <NUM> for heating an aerosol generating material. The induction heating assembly <NUM> comprises a generally cylindrical cavity <NUM> which is arranged to receive a correspondingly shaped generally cylindrical aerosol generating article in accordance with aspects of the present disclosure.

<FIG> shows the first example of the aerosol generating article <NUM> illustrated in <FIG> positioned in the cavity <NUM>. The cavity <NUM>, which constitutes a heating compartment, and the aerosol generating article <NUM> are arranged so that the filter <NUM> projects from the cavity <NUM> thus enabling a user to engage their lips with filter <NUM> to inhale a vapour or aerosol generated during operation of the system <NUM>.

The air inlets 50a, 50b are in communication with the cavity <NUM> and are arranged to direct air into the first region <NUM> of the aerosol generating material <NUM>. In a variation (not shown in the drawings), an air-permeable plug can be provided at the lower axial end of the cavity <NUM> viewed in <FIG> so that air through the air inlets 50a, 50b is uniformly distributed through the aerosol generating material <NUM> in the first region <NUM>.

The induction heating assembly <NUM> comprises a helical induction coil <NUM>, having first and second axial ends, which extends around the cylindrical cavity <NUM> and which can be energised by the power source <NUM> and control circuitry <NUM>. Thus, the induction coil <NUM> defines the cavity <NUM> in which the aerosol generating article <NUM> is positioned. It will be noted that the cavity <NUM> and the aerosol generating article <NUM> each have a respective longitudinal axis and that the longitudinal axes are substantially aligned with each other when the aerosol generating article <NUM> is positioned inside the cavity <NUM>.

The control circuitry <NUM> includes, amongst other electronic components, an inverter which is arranged to convert a direct current from the power source <NUM> into an alternating high-frequency current for the induction coil <NUM>. As will be understood by those skilled in the art, when the induction coil <NUM> is energised by the alternating high-frequency current, an alternating and time-varying electromagnetic field is produced. This couples with the inductively heatable susceptor <NUM> and generates eddy currents and/or magnetic hysteresis losses in the inductively heatable susceptor <NUM> causing it to heat up. The heat is then transferred from the inductively heatable susceptor <NUM> to the aerosol generating material <NUM> in the first region <NUM>, for example by conduction, radiation and convection, resulting in the generation of an aerosol. The aerosolisation of the aerosol generating material <NUM> in the first region <NUM> is facilitated by the addition of air from the surrounding environment through the air inlets 50a, 50b. As discussed above, the aerosol generated by heating the aerosol generating material <NUM> in the first region <NUM> then flows through the aerosol generating material <NUM> in the second region <NUM> where it cools and condenses to form a vapour or aerosol that is suitable for inhalation by a user of the system <NUM> through the filter <NUM>.

Referring now to <FIG>, there is shown a fifth example of an aerosol generating article <NUM> which is similar to the aerosol generating article <NUM> illustrated in <FIG> and in which corresponding elements are designated using the same reference numerals.

The aerosol generating material <NUM> is advantageously wrapped by a sheet of material, for example a paper wrapper <NUM>, to facilitate handling of the aerosol generating material <NUM>. The tubular inductively heatable susceptor <NUM> can be positioned in the first region <NUM> of the aerosol generating material <NUM> either before or after the aerosol generating material is wrapped by the paper wrapper <NUM>.

The aerosol generating article <NUM> includes a hollow tubular member <NUM> positioned between the second end <NUM> of the aerosol generating material <NUM> and the filter <NUM>. The aerosol generated during use of the article <NUM> by heating the aerosol generating material <NUM> cools and condenses as it flows through the hollow tubular member <NUM> to form a vapour or aerosol with optimum characteristics for inhalation by a user.

The aerosol generating article <NUM> includes an air-permeable member <NUM> in the form of an air-permeable cap at the first end <NUM> of the aerosol generating material <NUM> and in abutting co-axial alignment with the first region <NUM> of the aerosol generating material <NUM>. The air-permeable member <NUM> is typically a filter, for example comprising cellulose acetate fibres.

The various component parts of the aerosol generating article <NUM>, including the wrapped aerosol generating material <NUM> with the inductively heatable susceptor <NUM> positioned therein, the hollow tubular member <NUM>, the filter <NUM> and the air-permeable member <NUM>, are all wrapped by a sheet of material, for example a paper wrapper <NUM>, to maintain the positional relationship of the component parts of the assembled article <NUM>.

Referring now to <FIG>, there is shown a sixth example of an aerosol generating article <NUM> which is similar to the aerosol generating article <NUM> illustrated in <FIG> and in which corresponding elements are designated using the same reference numerals.

In the aerosol generating article <NUM>, the air-permeable member <NUM> includes an aperture <NUM>, for example a slit or a hole, which is adapted to receive a temperature sensor <NUM> positioned in the cavity <NUM> of the induction heating assembly <NUM> described above. As best seen in <FIG>, the aperture <NUM> is dimensioned so that the temperature sensor <NUM> extends fully into the aperture <NUM> but does not project from it. The aperture <NUM> is also advantageously dimensioned so that it has an inner diameter which is approximately the same as, or slightly less than, the outer diameter of the temperature sensor <NUM>. In this case, deposits can be removed from the surface of the temperature sensor <NUM> (thereby cleaning the temperature sensor <NUM>) by the air-permeable member <NUM> during insertion of the aerosol generating article <NUM> into the cavity <NUM> and/or during removal of the aerosol generating article <NUM> from the cavity <NUM>.

Referring now to <FIG>, there is shown a seventh example of an aerosol generating article <NUM> which is similar to the aerosol generating article <NUM> illustrated in <FIG> and in which corresponding elements are designated using the same reference numerals.

The air-permeable member <NUM> is in co-axial alignment with the first region <NUM> of the aerosol generating material <NUM> but is spaced from the first region <NUM> by a gap formed by a hollow tubular member <NUM> that is positioned between the air-permeable member <NUM> and the first end <NUM> of the aerosol generating material <NUM>.

As best seen in <FIG>, the temperature sensor <NUM> and/or the aperture <NUM> in the air-permeable member <NUM> are dimensioned so that the temperature sensor <NUM> extends through the air-permeable member <NUM> and projects into the gap formed by the hollow tubular member <NUM>.

Referring now to <FIG>, there is shown an apparatus and method for manufacturing the aerosol generating article <NUM> described above with reference to <FIG>.

In order to position the tubular inductively heatable susceptor <NUM> in the first region <NUM> of the aerosol generating material <NUM>, a pusher <NUM> is engaged with an end of the tubular inductively heatable susceptor <NUM> and moved towards the aerosol generating material <NUM> to push the tubular inductively heatable susceptor <NUM> into the first region <NUM> from the first end <NUM>. The aerosol generating material <NUM> is also supported at the second end <NUM> by an external support member <NUM> which forms part of a manufacturing apparatus (not shown) during insertion of the inductively heatable susceptor <NUM> into the first region <NUM>.

As shown in <FIG>, the pusher <NUM> can advantageously have a tapered end <NUM> having an external diameter which corresponds to the internal diameter of the tubular inductively heatable susceptor <NUM>, thus allowing the tapered end <NUM> to be inserted into the end of the tubular inductively heatable susceptor <NUM> and ensuring optimum alignment and cooperation between these two components.

Referring now to <FIG>, and in a variation of the embodiments described above with reference to <FIG>, the aerosol generating material <NUM> can be supported at the second end <NUM> during insertion of the tubular inductively heatable susceptor <NUM> into the first region <NUM> by an integral support member <NUM>. In the embodiment shown in <FIG>, the integral support member <NUM> is constituted by the filter <NUM> which is secured to the second end <NUM> of the aerosol generating material <NUM>, for example by tipping paper <NUM>, prior to insertion of the tubular inductively heatable susceptor <NUM> into the first region <NUM> from the first end <NUM>.

Referring now to <FIG>, there is shown an apparatus and method for manufacturing an aerosol generating article in which the aerosol generating material <NUM> in the second region <NUM> is compressed in a direction (denoted by the arrows in <FIG>) that is perpendicular to an axis of the aerosol generating material <NUM> and during insertion of the tubular inductively heatable susceptor <NUM> into the first region <NUM>.

Referring in particular to <FIG>, the aerosol generating material <NUM> is positioned in one of a plurality of receiving portions <NUM>, for example grooves, formed around an outer surface of a drum <NUM>. Each receiving portion <NUM> comprises a first receiving section <NUM> which corresponds to the position of the first region <NUM> of the aerosol generating material <NUM> and which does not compress the aerosol generating material <NUM> in the first region <NUM>. Each receiving portion <NUM> also comprises a second receiving section <NUM> which corresponds to the position of the second region <NUM> of the aerosol generating material <NUM> and which compresses the aerosol generating material <NUM> in the second region <NUM> during insertion of the inductively heatable susceptor <NUM> into the first region <NUM> from the first end <NUM>. The second receiving section <NUM> can have any suitable geometry, for example as shown in the non-limiting examples of <FIG>.

The aerosol generating material <NUM> is supported in the receiving portion <NUM> by a support drum <NUM>, for example during insertion of the inductively heatable susceptor <NUM> into the first region <NUM> at Position <NUM>. As best seen in <FIG>, the support drum <NUM> has a geometry which conforms to the geometry of the receiving portion <NUM>, for example as shown in <FIG>, to ensure that the aerosol generating material <NUM> is adequately supported in the receiving portion <NUM>, and in particular to ensure that the second region <NUM> of the aerosol generating material <NUM> positioned in the second receiving section <NUM> is adequately compressed during insertion of the inductively heatable susceptor <NUM> into the first region <NUM> at Position <NUM>.

Referring now to <FIG>, there is shown a seventh example of an aerosol generating article <NUM> which is similar to the aerosol generating articles described above and in which corresponding elements are designated using the same reference numerals.

The aerosol generating article <NUM> comprises aerosol generating material <NUM> having a first region <NUM> and a second region <NUM>, with the first region <NUM> being located downstream of the second region <NUM> relative to an aerosol flow direction within the article <NUM>.

The aerosol generating article <NUM> comprises an inductively heatable susceptor <NUM> positioned in the downstream first region <NUM> and extending from the second end <NUM> to the intermediate point <NUM>. The inductively heatable susceptor <NUM> is tubular as shown in <FIG>.

The aerosol generating article <NUM> also comprises a filter <NUM>, for example comprising cellulose acetate fibres, and a hollow tubular member <NUM> positioned between the second end <NUM> and the filter <NUM>. The various component parts of the aerosol generating article <NUM> are wrapped by a sheet of material, for example a paper wrapper <NUM>, to ensure that the component parts are retained in the correct positional relationship.

Claim 1:
An aerosol generating article (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising:
aerosol generating material (<NUM>) having first and second regions (<NUM>, <NUM>); and
an inductively heatable susceptor (<NUM>) in the first region (<NUM>);
characterized in that the inductively heatable susceptor (<NUM>) is tubular and the aerosol generating material (<NUM>) is positioned both inside and outside of the tubular inductively heatable susceptor (<NUM>).