EP4029386A1

EP4029386A1 - Filter for smoking article

Info

Publication number: EP4029386A1
Application number: EP21151304.9A
Authority: EP
Inventors: Andrew Robert John ROGAN; Alec WRIGHT
Original assignee: JT International SA
Current assignee: JT International SA
Priority date: 2021-01-13
Filing date: 2021-01-13
Publication date: 2022-07-20

Abstract

A vapour generating article comprising: a body having a first end and a second end opposite the first end, the body arranged to contain a vapour generating material; a filter comprising a mouthpiece end and an attachment end opposite the mouthpiece end, the attachment end arranged to be attached to the first end of the body; an airflow passageway within the filter configured to allow a vapour to flow into the filter through the attachment end from the first end of the body and out of the filter through the mouthpiece end; a restrictor arranged to adjust the cross sectional area of the air flow passageway to alter the pressure of the air flow within the airflow passageway.

Description

Field of Invention

The present disclosure relates to aerosol generating articles for use in an aerosol generation system in which an aerosol generating substrate is heated to form an aerosol. The disclosure is particularly applicable to a portable aerosol generation device, which may be self-contained and low temperature. Such devices may heat, rather than burn, tobacco or other suitable aerosol substrate materials by conduction, convection, and/or radiation, to generate an aerosol for inhalation.

Background

The popularity and use of reduced-risk or modified-risk devices (also known as vaporisers) has grown rapidly in the past few years as an aid to assist habitual smokers wishing to quit smoking traditional tobacco products such as cigarettes, cigars, cigarillos, and rolling tobacco. Various devices and systems are available that heat or warm aerosolisable substances as opposed to burning tobacco in conventional tobacco products.
A commonly available reduced-risk or modified-risk device is the heated substrate aerosol generation device or heat-not-burn device. Devices of this type generate an aerosol or vapour by heating an aerosol substrate that typically comprises moist leaf tobacco or other suitable aerosolisable material to a temperature typically in the range 150°C to 350°C. Heating an aerosol substrate, but not combusting or burning it, releases an aerosol that comprises the components sought by the user but not the by-products of combustion and burning.
In such devices, the aerosol substrate is typically included in a consumable that is held within a heating chamber and heated by a heater. The consumable contains a quantity of aerosol generating substrate and is able to generate a quantity of aerosol.
However, within such devices, a known issue is that the user experience does not entirely mimic that of a cigarette. In particular, HNB devices are known to provide a different inhalation experience to that offered by traditional tobacco products such as cigarettes.
It would be desirable to allow a consumer to adjust the pressure drop of a HNB device to suit their own taste and smoking characteristics.

Summary

According to a first aspect there is provided a vapour generating article comprising a body having a first end and a second end opposite the first end, the body arranged to contain a vapour generating material, and a filter comprising a mouthpiece end and an attachment end opposite the mouthpiece end, the attachment end arranged to be attached to the first end of the body. An airflow passageway within the filter is configured to allow a vapour to flow into the filter through the attachment end from the first end of the body and out of the filter through the mouthpiece end. The vapour generating article further comprises a restrictor arranged to adjust the cross sectional area of the air flow passageway to alter the pressure of the air flow within the airflow passageway.
In this way, the pressure drop of the vapour generating article may be adjusted as required by adjusting (e.g. increasing or decreasing) the size of the cross-sectional area of the airflow passageway. In particular, the cross-sectional size of the airflow passageway may be adjusted over a continuous range. This avoids deficiencies with known devices in which the pressure drop is typically fixed by the dimensions of, for example, an air inlet. Thus, greater flexibility is provided with regard to the control of the aerosol generating properties of the article, and the pressure drop may be adjusted during an aerosol generating session to more closely mimic the behaviour of traditional tobacco products such as cigarettes.
Advantageously, the restrictor of the vapour generating article allows a consumer to increase the pressure drop of a vapour generating article to suit their own taste and smoking characteristics. Some users of vapour generating articles have been known to deliberately constrict the filter section by biting or squeezing the filter section to increase the pressure drop, whilst other users find that no modification of the pressure drop is necessary.
Produce a single standard configuration with a fixed pressure drop would therefore not be suitable for some consumers. However, it is not practical to produce many different variations with different pressure drops that each are preferred by a small percentage of consumers. The provision of a restrictor therefore allows each consumer to modify the pressure drop of the vapour generating article themselves by providing a means of constricting the filter to adjust the size of the airflow passageway through the filter.
The restrictor may be arranged to reduce the cross-sectional area of the airflow passageway to increase the pressure drop of the air flow within the airflow passageway. Preferably, the restrictor may be arranged to reduce the cross-sectional area of the airflow passageway by application of pressure to the filter.
The restrictor may be arranged to increase the cross sectional area of the airflow passageway to decrease the pressure drop of the air flow within the airflow passageway. Preferably, the restrictor is arranged to increase the cross-sectional area of the airflow passageway by removal of pressure to the filter.
In some examples the restrictor comprises a shape memory alloy (SMA). Preferably, the shape memory alloy is configured to change shape as a function of temperature to adjust the size of the airflow passageway. In some cases, the shape memory alloy is a two-way shape memory alloy. An SMA provides a convenient method of increasing the pressure drop of a vapour generating article by constricting the filter with a shape memory alloy (SMA). The user is therefore able to increase pressure drop to suit their taste without the user having to come into to contact with any hot components of the vapour generating article.
Preferably, the shape memory alloy forms a noose around the filter and the noose is arranged to adjust the cross-sectional area of the airflow passageway by adjusting the amount of pressure applied to the filter. The noose arrangements allows direct constriction of the airflow passageway within the filter. In other words, the SMA noose acts directly against the filter, through the application of pressure to the filter, to adjust the cross-sectional area of the airflow passageway in order to adjust the pressure drop of the vapour generating article.
Instead of using an SMA noose, the restrictor may comprise a noose formed from a cord-like material. In this case, the noose is manually adjusted by the user to adjust the cross-sectional area of the airflow passageway. For example the user may pull on a part of the noose (e.g. an end of the noose) to cause the noose to tighten or constrict around the filter, reducing the cross-sectional area of the airflow passageway in the filter.
In some alternative arrangements, the shape memory alloy may comprise at least one shape memory alloy actuated flap that abuts the filter. In other alternatives, the shape memory alloy may comprise at least one shape memory alloy actuated blade that abuts the filter. These alternatives allow direct constriction of the airflow passageway within the filter through the application of pressure directly to the filter.
The restrictor may comprise an actuator configured to actuate the restrictor in order to adjust the cross-sectional area of the airflow passageway. Preferably, the actuator may comprise an electronic circuit coupled to the shape memory alloy and the actuator may further comprise a controller to control the electronic circuit. The controller may be arranged to pass an electrical current through the restrictor to cause the restrictor to change shape under the action of heating the restrictor via the electrical current. Thus, the size of the airflow passageway may be increased and/or decreased by providing a controlled supply of heat to the shape memory alloy. The SMA restrictor is therefore configured to adjust the size of the airflow passageway as a function of temperature. In this way, the pressure drop may be adjusted in response to a change in temperature.
In some developments the actuator may comprise a primary heater and heat from the primary heater may be arranged to change the shape of the shape memory alloy. Thus, the pressure drop may be varied during the aerosol generating session (e.g. without requiring user input), meaning that the size of the airflow passageway, and thus the pressure drop, may be configured to vary in a manner which replicates the behaviour of traditional tobacco products.
In other examples, the filter comprises the restrictor. In this case, the restrictor is not a separate component but forms at least part of the filter. This may reduce the number of individual components within the vapour generating article, reducing the complexity of the device.
The restrictor may be elastically deformable. Preferably, the restrictor may comprise a material that does not immediately return to its original shape once the application of pressure to the restrictor has been removed. The restrictor therefore undergoes a reversible deformation in which the effect of the deformation is retained for a period of time. In other words, the restrictor has a memory-effect behaviour. Preferably, the material may comprise polyurethane foam, also known as memory foam.
Typically, with conventional filters when pressure from a user is released the filter tends to substantially return to its original shape, thus the consumer needs to keep the pressure applied throughout the use of the vapour generating article. Having to continually apply pressure to the filter to keep the pressure drop high is inconvenient. The use of memory foam allows the user to constrict the filter such that the filter remains in the constricted position for a period time and does not substantially return to its original shape once the manual force has been released. This is convenient for the user as they may experience prolonged, uninterrupted vaping experiences.
In some examples, the restrictor may comprise a manually operable restrictor wherein manual application of pressure to the restrictor reduces the cross-sectional area of the airflow passageway. In particular, the user may manually apply pressure to the memory foam restrictor, allowing the user to directly adjust the pressure drop through direct adjustment of the airflow passageway within the filter. Furthermore, manual adjustment provides a less complex device which is cheaper to manufacture and more simple to operate by a user.
Manually applying pressure to the restrictor may provide the user with substantially instant feedback in relation to how much pressure they are applying and thus how much restriction will be applied to the airflow passageway. This may allow the user to make more accurate pressure drop adjustments during the vaping session.
Preferably, the material forms the filter and the airflow passageway passes through the material filter. Thus, in this case, the filter is formed from the restrictor material, for example memory foam, and so substantially the whole of the filter can be used to adjust the airflow passageway. This arrangements means that the user does not need to be accurate or precise about which part of the filter they are applying pressure to in order to adjust the cross-sectional area of the airflow passageway, making the restrictor quick and easy to use.
In some developments, the filter may comprise at least two segments. A first segment may comprise the restrictor and a second segment may not comprise the restrictor. In this way, only part of the filter can be used to adjust the airflow passageway of the filter. Preferably, the at least two segments may be located adjacent each other. There may be a plurality of first and/or second segments. Preferably the plurality of first and/or second segments are alternately arranged. Providing multiple segments gives the user the ability to compress a number of smaller segments to suit their pressure drop requirements rather than trying to compress one larger segment to the same level each time the device is used. Multiple segments may therefore allow the user to have a more repeatable vaping experience.
According to another aspect there is provided a vapour generating system comprising a vapour generating article according to any the above described vapour generating articles of and a vapour generating device configured to receive the vapour generating article and generate a vapour from the vapour generating material.

Brief Description of Drawings

Embodiments of the present invention will be now described by way of example only with reference to the accompanying drawing in which:

Figure 1 shows an example aerosol generating article;
Figures 2A and 2B show a filter having a first example of a restrictor;
Figures 3A and 3B show a filter having a second example of a restrictor;
Figures 4A and 4B show a filter having a third example of a restrictor; and
Figures 5A and 5B shows a filter having a fifth example of a restrictor.

Detailed Description

Referring to Fig. 1 an example aerosol generating article 1, in the form of an elongate consumable 1, is shown located within an aerosol generating device 2 in order to generate an aerosol.
The aerosol generating article 1 comprises a rod-shaped portion 11, and a filter 14.
The rod-shaped portion 11 comprises aerosol generating substrate 12 that extends over a portion of the length of the rod-shaped portion 11. The aerosol generating substrate 12 is arranged at an end of the aerosol generating article 1 that is within a heating chamber of the aerosol generating device 2 and furthest from an opening of the heating chamber. The aerosol generating substrate 12 is a material which, when heated, generates an aerosol. The aerosol generating substrate 12 may, for example, comprise tobacco or nicotine. The aerosol is drawn out of the aerosol generating article 1 by air flow through the filter 14.
The aerosol generating device 2 comprises a heating chamber 21 and a heater 22.
The heating chamber 21 is a tubular structure with an internal hollow in which the aerosol generating article 1, or the rod-shaped portion 11 of the aerosol generating article 1, may be received. Specifically, the heating chamber comprises a side wall extending between a first end 212 and a second end 213. The first end 212 is open, or openable in use, in order to allow the rod-shaped portion 11 to be inserted. The second end 213 may be open as shown in Fig. 1A, in order to provide an air inlet for air to flow through the aerosol generating article. Alternatively, the second end 213 may be closed in order to improve heating efficiency of the heating chamber 21.
The heating chamber 21 may be formed from ceramic or metal. For example, the heating chamber 21 may be formed by bending or stamping sheet metal. The heater 22 may be any heater suitable to deliver heat into the internal hollow of the heating chamber 21 through its side wall. For example, the heater may be in the form of a resistive track driven by electricity. Alternatively, other types of heater may be used such as ones in which heat is provided by a chemical reaction such as fuel combustion. The heating chamber may further be surrounded by a heat insulator such as a vacuum tube, heat insulation fibre and/or aerogel.
In use, the heater 22 is arranged to heat the heating chamber 21 to a temperature sufficient to cause the aerosol generating substrate 12 to release an aerosol, without burning the aerosol generating article 1. In particular, the heater 22 is configured to heat the aerosol generating substrate 12 to a maximum temperature between 150°C and 350°C, more preferably to a temperature between 200°C and 350°C.
Although the heater 22 is shown outside the heating chamber 21 in Fig. 1A, the heater 22 may in some embodiments be arranged inside the heating chamber 21.
The aerosol generating article 1 further comprises an aerosol cooling region 15. The aerosol cooling region 15 extends over a portion of the length of the aerosol generating article 1 and comprises a hollow tubular portion of the aerosol generating article 1. This hollow tubular portion allows an aerosol (generated by heating the aerosol generating substrate 12) to pass through the aerosol generating article 1 without leaking through the sides of the hollow tubular portion. The aerosol cooling region 15 does not overlap with the part of the aerosol generating article 1 that is being heated by the heater 22, which may be referred to as a heating region, so aerosol will not continue to be heated within the aerosol cooling region 15.
As mentioned, the aerosol substrate 12 is arranged at the end of the aerosol generating article 1 that is within the heating chamber 21 and furthest from the opening 212. The filter 14 is arranged at the other end that is closest to the opening 212. The aerosol cooling region 15 extends along the length of the aerosol generating article 1 between the aerosol generating substrate 12 and the filter 14. This ensures that, in use, a generated aerosol may be cooled before inhalation by a user.
Further details of the filter 14 will now be described.
The filter 14 comprises a mouthpiece end and an attachment end, opposite the mouthpiece end which attaches to the rod-shaped portion 11. The filter further comprises airflow passageway 16 within the filter which allows the generated vapour to flow into the filter 14 via the attachment end from the rod-shaped portion 11 and out of the filter 14 through the mouthpiece end.
As shown in Figures 2A - 5B, the aerosol generating article also includes a restrictor 18 (i.e. an adjustable opening member) configured to control the flow of air through the airflow passage 16. This is achieved by adjusting the cross sectional area of the air flow passageway 16 to alter the pressure of the air flow within the airflow passageway 16. In other words, the size of the airflow passageway 16 may be controlled to adjust the flow of air into and along the airflow passage 16.
For example, the size of the airflow passageway 16 may be increased from a first size (for example as seen in Figure 2B) to a second size (for example as seen in Figure 2A) to increase the flow of air through the filter 14, thereby decreasing the pressure drop. Conversely, the size of the airflow passageway 16 may be decreased from the second size (as seen in Figure 2A) to the first size (as seen Figure 2B) to decrease the flow of air through the filter, thereby increasing the pressure drop. The skilled person will appreciate that the sizes of the cross-sectional area of the airflow passageway 16 depicted in exemplary Figures 2A and 2B serve only as an illustration, and the airflow passageway 16 may be controlled to vary across a continuous range of sizes, such that the pressure drop may be precisely controlled by varying the size of the airflow passageway 16.
The restrictor adjusts the size of the airflow passageway 16 through the use of pressure. In particular, applying pressure to the filter 14 via the restrictor 18 causes the restrictor 18 to reduce the cross-sectional area of the airflow passageway 16. If this pressure is then removed, the cross-sectional area of the airflow passageway 16 will increase until it returns to its original size. In some cases the size of the airflow passageway 16 will increase rapidly to its initial default size. In other cases the size of the airflow passageway 16 will gradually increase over a period of time. In this case, the gradual increase has the effect that the airflow passageway 16 maintains a reduced size for a period of time before returning to its default size. In this context, the default or initial size of the airflow passageway 16 is the size of the cross sectional area of the airflow passageway 16 when no pressure has been applied to the filter 14.
In the examples illustrated in the Figures, the airflow passageway 16 has a circular cross-sectional area and the radius of the airflow passageway 16 is varied to alter the cross-sectional area of airflow passageway 16. It will be appreciated, however, that the airflow passageway 16 may have a different shaped cross-sectional area, such as a triangle, oval, or rectangle.
The restrictor 18 can take on different forms, some of which will be described in more detail below.
In a first exemplary form, the restrictor 18 comprises a shape memory alloy (SMA), and preferably a two-way shape memory alloy. For example, the restrictor 18 may comprise Ni-Ti, Cu-AI-Ni, Cu-Zn-AI or another suitable shape memory alloy. The shape memory alloy exhibits the shape memory effect such that it deforms (i.e. undergoes a phase transformation) as a function of temperature to adjust the size of the airflow passageway 16 defined by the restrictor 18. In this way, the SMA acts to reduce the cross sectional area of the airflow passageway through the filter 14 filter by applying pressure (i.e. squeezing) and thus increasing the pressure drop through the stick.
The SMA can be provided in a number of different forms, or configurations. In a first configuration, as illustrated in Figures 2A and 2B, the SMA takes the form of an SMA wire 18a which forms a noose-like arrangement around the external surface of the filter 14. Thus, in this example, the SMA is formed in a ring shape (e.g. donut, torus). The ring-shaped SMA wire may be necessarily formed in a continuous ring but also be also be formed from a pair of half-circle portions.
In a first position, shown in Figure 2A, the SMA wire 18a is in contact with an external surface of the filter, having a size that is substantially the same as the circumference of the filter 14. The first position may correspond to a low temperature position of the restrictor 18 in which no pressure is being applied to any part of the filter and so the airflow passageway is in its default size.
In a second position, shown in Figure 2B, which may correspond to a high temperature position of the restrictor 18, the SMA wire 18a is deformed such that the ring-shape wire reduces in size so that it has a size that is smaller than the circumference of the filter 14. The reduction in size has the effect of applying pressure to part of the filter 14 and so the size of the airflow passageway 16 through the filter 14 is reduced. The deformation of the SMA wire 18a occurs due to a temperature induced phase transformation, i.e. the shape memory effect.
In a second configuration, illustrated in Figures 3A and 3B, the SMA takes the form of an SMA actuated flap 18b that abuts at least a portion of the filter 14. In some cases, there may be more than one SMA actuated flap 18b located around the circumference of the filter 14.
In relation to the second configuration, in a first position illustrated in Figure 3A the SMA flap 18b is in contact with an external surface of the filter, located next to the external surface of the filter 14 and extends along at least part of the longitudinal length of the filter 14. In this position, the SMA flap has a bent or U-shaped form. As before, the first position may correspond to a low temperature position of the restrictor 18 in which no pressure is being applied to any part of the filter and so the airflow passageway is in its default size.
In a second position of the second configuration, illustrated in Figure 3B which may correspond to a high temperature position of the restrictor 18, the SMA flap is deformed such that the SMA flap 18b straightens inwards towards the filter 14 compressing part of the filter 14 which reduces the size of the airflow passageway 16. In other words the SMA flap 18b deflects in an inward radial direction with respect to the filter 14. The deflection/deformation of the shape memory alloy flap therefore adjusts the cross sectional size of the airflow passageway 16.
In a third configuration, illustrated in Figures 4A and 4B, the SMA takes the form of an SMA actuated blade 18c that abuts at least a portion of the filter 14. In some cases, there may be more than one SMA actuated blade 18c located around the circumference of the filter 14.
In relation to the third configuration, in a first position shown in Figure 4A the SMA blade 18c is perpendicular to an external surface of the filter. Again, the first position may correspond to a low temperature position of the restrictor 18 in which no pressure is being applied to any part of the filter and so the airflow passageway is in its default size.
In a second position of the second configuration, shown in Figure 4B, which again may correspond to a high temperature position of the restrictor 18, the SMA blade is deformed such that the SMA blade 18c extends or straightens inwards towards the filter 14 compressing part of the filter 14 which reduces the size of the airflow passageway 16. In particular, the SMA blade 18c pushes on a part of the filter 14 to compress the filter 14, and in some cases the SMA blade my exhibit a slight guillotine action and slide through the filter 14 during compression. Thus, the SMA blade 18c deflects in an inward radial direction with respect to the filter 14, and this deflection/deformation of the shape memory alloy blade adjusts the cross sectional size of the airflow passageway 16.
Advantageously, using an SMA allows the restrictor to be directly constrict the filter 14 in order to adjust the size of the airflow passage way 16 and thus the pressure drop. This allows a user to adjust the pressure drop without the user needing to come into contact with any parts of the vapour generating device 2 which may be hot.
The SMA can be actuated in number of different ways. Preferably, the SMA is provided as part of an electronic circuit that is controlled by a user of the vapour generating article and passing electrical current though the SMA directly causes self-heating and a change in shape of the SMA. In this case, the restrictor comprises an actuator which comprises an electronic circuit coupled to the SMA and a controller to control the electronic circuit. The controller allows an electrical current to pass through the restrictor to cause the restrictor to change shape under the action of heating the restrictor via the electrical current.
Said another way, the temperature of the restrictor 18 may be varied by adjusting a controlled supply of heat to the restrictor 18. For example, the supply of heat to the restrictor 18 may be controlled using an electronic controller. Advantageously, this allows the size of the airflow passageway 16 to be precisely controlled. As the pressure drop within the aerosol generating device 2 depends on the size of the airflow passageway 16, the supply of heat may be automatically controlled such that the pressure drop during the aerosol generating session mimics the pressure drop within traditional tobacco products. Alternatively or additionally, the user may be able to manually control the supply of heat to the restrictor 18. This may be achieved using, for example, mechanical means (e.g. a slider, solenoid) and/or be triggered by electronic means (e.g. buttons, touchscreen etc.). Thus, the user is able to control the pressure drop during the aerosol generating session to suit their personal preference.
In an alternative actuation means, the temperature of the restrictor 18 may vary in accordance with the (indirect) heating provided by a heater in the vapour generating device 2. In this case, the SMA actuator comprises a primary heater and heat from the primary heater changes the shape of the shape memory alloy. This has the effect that heat dissipated from the primary heater of the aerosol generating device 2 can be used, instead of wasted, to adjust the cross sectional area of the airflow passageway, adjusting the pressure drop.
Looking back at exemplary Figures 2A and 2B, the first size of airflow passageway 16 (depicted in Figure 2A) may correspond to a state where the restrictor 18 has not been heated (e.g. the restrictor 18 is at room temperature). The second size of airflow passageway 16 (depicted in Figure 2B) may correspond to a state where the restrictor 18 has been heated, either using a controlled supply of heat or by indirect heating from the heater. Again, the skilled person will appreciate that the first and second sizes of airflow passageway 16 are not intended to be limiting, and the size of the airflow passageway 16 may be configured to continuously vary across a continuous temperature range. That is, the restrictor 18 is configured to adjust the size of the airflow passageway 16 across a continuous range, i.e. the airflow passageway 16 is not limited to switching between just two sizes of airflow passageway 16.
Referring back to the different forms that the restrictor may take, in a second exemplary form, illustrated in Figures 5A and 5B, the restrictor 18 may form part of the filter body and so in this case the filter comprises the restrictor 18. In particular, the restrictor 18 comprises a memory-foam like material 18d that remains in the constricted form once the application of pressure to the restrictor has been removed.
In other words, the restrictor material does not substantially return to its original shape once the application of pressure to the restrictor has been removed. Instead, it retains its deformed shape for a period of time. It should be noted that the deformation is nonetheless reversible, but not immediately reversible. The restrictor material has some memory of its deformed shape but this memory is not permanent.
Any suitable memory-retaining material can be used to provide a memory foam restrictor 18d, for example polyurethane foam. As the restrictor 18 forms part of the filter 14, the filter 14 can be considered to be at least partially made from memory foam. In some cases, the whole filter 14 is formed from the memory foam, and the airflow passageway 16 passes through the memory foam filter 14.
Providing a memory foam filter means that when pressure applied to the filter 14 (e.g. through the user squeezing or biting the filter) is released, the filter 14 substantially retains to its altered shape and so the user does not need to keep the pressure applied throughout the use of the aerosol generating article 1.
In this example, the restrictor 18 is a manually operable restrictor such that manual application of pressure to the restrictor causes the cross-sectional area of the airflow passageway 16 to be adjusted, which adjusts the pressure drop within the filter 14.
In some arrangements, the filter 14 comprises a multi-segment filter arrangement in which portions of conventional filter material are alternately located next to portions of filter material including memory foam. In this case the filter can be thought of as comprising at least a first segment and a second segment. The first segment comprises the restrictor, which may be a memory foam restrictor, and the second segment does not comprise a restrictor. In other words, only the first segment is able to adjust the cross-sectional are of the airflow passageway within the filter. The first and second segments are located adjacent to each other such that a filter adjusting portion (i.e. the first segment) is located next to a fixed filter portion (i.e. the second segment). As will be appreciated there may be more than one of the first segment and/or the second segment, and these plurality of segments may be alternately arranged within the filter.
As has been discussed, the vapour generating article 1 may be connected with a vapour generating device 2. In this case, a vapour generating system is formed comprising the a vapour generating article 1 and the vapour generating device 2 which receives the vapour generating article 1.
It should be understood that the aerosol generation device is an electronic cigarette which could equally be referred to as a "heated tobacco device", a "heat-not-burn tobacco device", a "device for vaporising tobacco products", and the like, with this being interpreted as a device suitable for achieving these effects. The features disclosed herein are equally applicable to devices which are designed to vaporise any aerosol generating medium.
The aerosol generating substrate 12 may include tobacco, for example in dried or cured form, in some cases with additional ingredients for flavouring or producing a smoother or otherwise more pleasurable experience. In some examples, the aerosol generating substrate 12 such as tobacco may be treated with a vaporising agent. The vaporing agent may improve the generation of vapour from the aerosol generating substrate 12. The vaporising agent may include, for example, a polyol such as glycerol, or a glycol such as propylene glycol. In some cases, the aerosol generating substrate 12 may contain no tobacco, or even no nicotine, but instead may contain naturally or artificially derived ingredients for flavouring, volatilisation, improving smoothness, and/or providing other pleasurable effects.
The aerosol generating substrate 12 may be provided as a solid or paste type material in shredded, pelletised, powdered, granulated, strip or sheet form, optionally a combination of these. Equally, the aerosol generating substrate 12 may be a liquid or gel. Indeed, some examples may include both solid and liquid/gel parts. Indeed, some examples may include both solid and liquid/gel parts. In some examples, the substrate 12 may be a solid block, or may be loose material packed in a wrapper 13. Preferably the substrate comprises randomly oriented tobacco strands containing tobacco powder and an aerosol former. Suitable aerosol formers include: a polyol such as sorbitol, glycerol, and glycols like propylene glycol or triethylene glycol; a non-polyol such as monohydric alcohols, acids such as lactic acid, glycerol derivatives, and esters such as triacetin, triethylene glycol diacetate, triethyl citrate, glycerin or vegetable glycerin. In some embodiments, the aerosol generating agent may be glycerol, propylene glycol, or a mixture of glycerol and propylene glycol.
Whilst the aerosol generating substrate 12 will typically produce a gas or a solid and/or liquid suspension in gas when heated, it will be appreciated that the terms 'vapour' and 'aerosol' are generally used interchangeably here, and refer generally to the substance which is produced when the aerosol generating substrate 12 is heated, to produce a suspension of particles or droplets of any size.
As used herein, the term "fluid" shall be construed as generically describing non-solid materials of the type that are capable of flowing, including, but not limited to, liquids, pastes, gels, powders and the like. "Fluidized materials" shall be construed accordingly as materials which are inherently, or have been modified to behave as, fluids. Fluidization may include, but is not limited to, powdering, dissolving in a solvent, gelling, thickening, thinning and the like.

Claims

A vapour generating article comprising:
a body having a first end and a second end opposite the first end, the body arranged to contain a vapour generating material;

a filter comprising a mouthpiece end and an attachment end opposite the mouthpiece end, the attachment end arranged to be attached to the first end of the body;

an airflow passageway within the filter configured to allow a vapour to flow into the filter through the attachment end from the first end of the body and out of the filter through the mouthpiece end;

a restrictor arranged to adjust the cross sectional area of the air flow passageway to alter the pressure of the air flow within the airflow passageway.
The vapour generating article according to claim 1 wherein the restrictor is arranged to reduce the cross-sectional area of the airflow passageway to increase the pressure drop of the air flow within the airflow passageway.
The vapour generating article according to claim 1 or 2 wherein the restrictor is arranged to reduce the cross-sectional area of the airflow passageway by application of pressure to the filter.
The vapour generating article according to any preceding claim wherein the restrictor is arranged to increase the cross sectional area of the airflow passageway to decrease the pressure drop of the air flow within the airflow passageway.
The vapour generating article according to any preceding claim wherein the restrictor is arranged to increase the cross-sectional area of the airflow passageway by removal of pressure from the filter.
The vapour generating article according to any preceding claim wherein the restrictor comprises a shape memory alloy.
The vapour generating article according to claim 6 wherein the shape memory alloy forms a noose around the filter and the noose is arranged to adjust the cross-sectional area of the airflow passageway by adjusting the amount of pressure applied to the filter.
The vapour generating article according to claim 6 wherein the shape memory alloy comprises at least one shape memory alloy actuated flap that abuts the filter.
The vapour generating article according to claim 6 wherein the shape memory alloy comprises at least one shape memory alloy actuated blade that abuts the filter.
The vapour generating article according to any preceding claim wherein the restrictor comprises an actuator configured to actuate the restrictor in order to adjust the cross-sectional area of the airflow passageway.
The vapour generating article according to claim 10 wherein the actuator comprises an electronic circuit coupled to the shape memory alloy and a controller to control the electronic circuit, wherein the controller is arranged to pass an electrical current through the restrictor to cause the restrictor to change shape under the action of heating the restrictor via the electrical current.
The vapour generating article according to claim 10 wherein the actuator comprises a primary heater and heat from the primary heater is arranged to change the shape of the shape memory alloy.
The vapour generating article according to any of claims 1 to 5 wherein the filter comprises the restrictor.
The vapour generating article according to claim 13 wherein the restrictor comprises a material that does not immediately return to its original shape once the application of pressure to the restrictor has been removed.
The vapour generating article according to claim 14 wherein the material comprises polyurethane foam.
The vapour generating article according to any of claims 13 to 15 wherein the restrictor comprises a manually operable restrictor wherein manual application of pressure to the restrictor reduces the cross-sectional area of the airflow passageway.
The vapour generating article according to any of claims 14 to 16 wherein the material forms the filter and the airflow passageway passes through the material filter.
The vapour generating article according to any of claims 14 to 16 wherein the filter comprises at least two segments, wherein a first segment comprises the restrictor and a second segment does not comprise the restrictor.
The vapour generating article according to claim 18 wherein the at least two segments are located adjacent each other.
A vapour generating system comprising:
a vapour generating article according to any of claims 1 to 19; and

a vapour generating device configured to receive the vapour generating article and generate a vapour from the vapour generating material.