WO2024153561A1

WO2024153561A1 - A heater for an aerosol generation device

Info

Publication number: WO2024153561A1
Application number: PCT/EP2024/050718
Authority: WO
Inventors: Juraj LEHOCKY
Original assignee: Jt International Sa
Priority date: 2023-01-16
Filing date: 2024-01-12
Publication date: 2024-07-25

Abstract

There is provided a heater for an aerosol generation device, the heater comprising: a receiving surface for receiving an aerosol precursor material thereon, wherein the receiving surface comprises one or more flow-directing structures configured to direct a flow of the aerosol precursor material on the receiving surface of the heater.

Description

A Heater for an Aerosol Generation Device

The present disclosure relates to a heater for an aerosol generation device, an aerosol generation device including the heater and a method of using the aerosol generation device.

Background

The popularity and use of reduced-risk or modified-risk devices (also known as vaporisers, vapour provision device or aerosol generation devices) 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 aerosol precursor material as opposed to burning tobacco in conventional tobacco products. Many kinds of electric smoking devices are available on the market. The most popular are known as e- cigarettes and vaporize an e-liquid to an inhalable vapor.

A commonly available device is the aerosol generation device or heat-not-burn device. Devices of this type generate aerosol or vapour by heating an aerosol substrate that typically comprises moist leaf tobacco or other suitable vaporizable material to a temperature typically in the range 150°C to 350°C. Heating an aerosol substrate, but not combusting or burning it, releases aerosol that comprises the components sought by the user but not the toxic and carcinogenic by-products of combustion and burning. Furthermore, the aerosol produced by heating the tobacco or other aerosol precursor material does not typically comprise the burnt or bitter taste resulting from combustion and burning that can be unpleasant for the user and so the substrate does not therefore require the sugars and other additives that are typically added to such materials to make the aerosol more palatable for the user. However, the heat-not-burn device requires sufficient insulation to protect a user from the relative high heater temperatures.

Another commonly available device is an e-cigarette. The e-cigarette generates an aerosol from an aerosol precursor material, typically in liquid form. The e-cigarette often comprises a wicking material, for example cotton or ceramic, combined with a heater material, such as a wire or heater track. This is disadvantageous because it requires the aerosol precursor material to move from one area to another within the device before aerosolisation can occur, which can lead to clogging and also requires the aerosol precursor material to have a relatively low viscosity to enable it to flow through the device. The aerosol provision device and/or consumable typically comprise reservoirs which retain the aerosol precursor material before the aerosol precursor material moves to the wicking material for aerosolisation. Reservoirs normally require ample space within the device to hold the aerosol precursor material causing devices to be bulky. Furthermore, counterfeit, or third-party aerosol precursor material may be used as a refill after the initial aerosol precursor material within the reservoirs has been exhausted.

Figure 1 shows an example of a heater 100 according to embodiment which is not the invention. For ease of manufacturing, heaters 100 in this embodiment have a substantially flat surface for receiving an aerosol precursor material. The heater 100 comprises one or more resistive heating elements embedded therein or provided on the surface. The resistive heating elements are configured to generate heat in response to an electric current being received. However, heater 100 as shown in Figure 1 tends to lead to difficulties in maintaining aerosol precursor material on the surface as and lead to inefficiencies. In particular, very viscous aerosol precursor material is required which flows slowly over the surface of the heater to reduce wastage. However, this viscous aerosol precursor material may reduce the sensory experience.

It is an object of the present invention to overcome at least some of the above- mentioned problems.

Summary

According to the present disclosure there is provided a heater for an aerosol generation device, the heater comprising: a receiving surface for receiving an aerosol precursor material thereon, wherein the receiving surface comprises one or more flow-directing structures configured to direct a flow of the aerosol precursor material on the receiving surface of the heater.

Receiving the aerosol precursor material on a receiving surface of the heater and subsequently directing a flow of the aerosol precursor material on the receiving surface of the heater means that the heater is more efficient. The aerosol precursor material may be retained on the receiving surface in a fluid form for longer and there is less chance for the aerosol precursor material to spill over an edge of the heater or splash away from the heater, in use. In addition, the aerosol precursor material may be directed towards a specific part of the heater to aid aerosolization and reduce aerosolization times. Reducing “overflow” of aerosol precursor material from the heater also leads to easier cleaning of the device.

In one example, the one or more flow-directing structures comprises a peripheral barrier arranged towards a periphery of the receiving surface. The peripheral barrier aids in preventing the aerosol precursor material from flowing over an edge of the heater, thereby reducing waste of the aerosol precursor material, in use.

In one example, the receiving surface comprises a substantially planar region and the one or more flow-directing structures are raised from the substantially planar region. In particular, the flow-directing structure(s) may be formed of a protrusion (protrusions) extending from the substantially planar region. Having a substantially planar region allows for a relatively simple construction of the heater and enables one or more heating elements to be efficiently located within the heater.

In one example, the one or more flow-directing structures of the receiving surface comprises a protrusion comprising a peak on which the aerosol precursor material is configured to be received, e.g., as a stream of precursor material projected under pressure or gravity. In other words, the peak is for receiving the aerosol precursor material. In some examples the protrusion is for receiving the aerosol precursor material. This arrangement reduces the turbulence of the aerosol precursor material when it is received on the heater, thereby reducing the likelihood of the aerosol precursor material spilling over the edge of the heater.

In one example, a height of the peripheral barrier is equal to or greater than a height of the protrusion. This arrangement reduces the likelihood of the aerosol precursor material flowing off the surface of the heater. Further, having a peripheral barrier with a relatively large height means that more aerosol precursor material may be stored on the receiving surface of the heater prior to aerosolization, in use. Hence, the receiving surface and the peripheral barrier creates a reservoir for the aerosol precursor material. Further, “time to puff’ would be reduced and there may be a denser aerosol generated. In other words, the fluid would not flow off the heater and so a substantial amount of fluid is transformed into the aerosol. This would generate denser aerosol compared to situation when the fluid flows off the heater and is lost. In one example, the protrusion has a substantially dome shaped region comprising the peak for receiving the aerosol precursor material. The dome shaped region aids with avoiding splashing from the receiving surface of the received aerosol precursor material. The dome shaped region also helps with fluid flow onto the receiving surface.

In one example, the dome shaped region comprises a region that curves away from the peak. That is to say that there is a gradual curve in the surface away from the peak of the protrusion, which aids with reducing the turbulence of the aerosol precursor material received on the receiving surface.

In one example, a gradient of the surface of the peak is at a minimum value at the peak of the protrusion. This aids with avoiding splashing of the received aerosol precursor material.

In one example, the peak is a smooth peak. That is to say that there is not a sharp change of gradient or height in the receiving surface at the position of the peak. This aids with avoiding splashing of the received aerosol precursor material.

In one example, the heater comprises a heating element configured to generate heat, wherein the heating element is configured to extend into the protrusion of the receiving surface. Extending the heating element into the protrusion means that aerosol precursor material may be heated immediately as it is received on the receiving surface.

In one example, the flow-directing structures of the receiving surface comprises one or more intermediate partial barriers located between a centre of the receiving surface and a periphery of the receiving surface. The one or more intermediate partial barriers further inhibit flow of the aerosol precursor material over the receiving surface of the heater.

In one example, the one or more intermediate partial barriers extend at least partially along radial lines from the centre of the receiving surface and the periphery of the receiving surface. In this example, the one or more intermediate partial barriers help guide (or control) a flow of aerosol precursor material to flow in various direction on the heater. For example, the intermediate partial barriers may direct the aerosol precursor material to flow substantially symmetrically about a centre of the heater.

In one example, the heater has a substantially circular profile. The circular profile is easier to manufacture and lowers heat and associated mechanical stresses created in rectangular design corners. In one example, the one or more intermediate partial barriers comprises a first intermediate partial barrier arranged at a first predetermined distance from the centre of the receiving surface, the first intermediate partial barrier comprising one or more first passages to permit flow of the aerosol precursor material to the periphery of the receiving surface, in use. This arrangement leads to further resistance to the flow of aerosol precursor material over the receiving surface of the heater.

The one or more intermediate partial barriers comprises a second intermediate partial barrier arranged at a second predetermined distance from the centre of the receiving surface, the second intermediate partial barrier comprising one or more second passages to permit flow of the aerosol precursor material to the periphery of the receiving surface, in use. Providing a second intermediate partial barrier further inhibits the flow of aerosol precursor material of the receiving surface of the heater thereby improving the efficiency of the heater.

In one example, the one or more first passages are offset from the one or more second passages. In this arrangement the aerosol precursor material must follow a meandering path from a centre of the heater to a periphery of the heater, which increases the time on which the aerosol precursor material will be on the heater and increasing the likelihood that the aerosol precursor material will be aerosolised.

In one example, the heater comprises a non-absorbent ceramic material. The receiving surface may be formed of non-absorbent ceramic material. The non-absorbent ceramic heater enables the aerosol precursor material to be retained on the receiving surface of the heater, in use.

In one example, the receiving surface is a continuous surface. By continuous surface, it is means that the receiving surface does not comprise apertures or openings going into the surface of the receiving surface. For example, the receiving surface may comprise a substantially planar region and the one or more flow-directing structures that are raised from the substantially planar region. The one or flow directing structures may rise gradually from the planar region or there may be a step change in height of the receiving surface going from the planar region to the one or more flow-directing structures, however, in both of these examples there would still be a continuous surface on the receiving surface. That is to say, in these examples there are not one or more openings going into the receiving surface, which would be problematic as in this case it is intended for the aerosol precursor material in a form of a fluid is retained on the receiving surface to enable it to be aerosolised. Continuous surface is intended to mean uninterrupted by openings.

According to one example, there is provided an aerosol generation device comprising: the heater as described above; and an aerosol precursor material ejector configured to eject the aerosol precursor material to the receiving surface of the heater. The device efficiently transfers the aerosol precursor material to a surface of the heater for aerosolisation.

In one example, the aerosol precursor material ejector comprises a chamber configured to at least temporarily store the aerosol precursor material and a nozzle through which the aerosol precursor material is ejected to the receiving surface of the heater, wherein the nozzle is substantially aligned with the protrusion of the receiving surface. Substantially aligning the nozzle with the protrusion of the receiving surface means that the aerosol precursor material is transferred to the heater in a less turbulent manner.

According to one example, there is provided a method of using the aerosol generation device as described above, the method comprising: receiving an input into the device; and ejecting aerosol precursor material from the aerosol precursor material ejector to the receiving surface of the heater upon receipt of the input, wherein a flow of the aerosol precursor material on the receiving surface of the heater is directed by the one or more flow-directing structures of the receiving surface. Receiving the aerosol precursor material on a receiving surface of the heater and subsequently directing a flow of the aerosol precursor material on the receiving surface of the heater means that the heater is more efficient. The aerosol precursor material may be retained on the receiving surface in a fluid form for longer and there is less chance for the aerosol precursor material to spill over an edge of the heater or splash away from the heater, in use. In addition, the aerosol precursor material may be directed towards a specific part of the heater to aid aerosolization. The above-mentioned features may be combined in various combinations.

Brief Description of the

Examples of the present disclosure will now be described with reference to the accompanying drawings.

Figure 1 shows an example of a heater, which is not the invention;

Figure 2 shows a cross sectional view of the aerosol generation device including a heater;

Figure 3A shows an example of a heater;

Figure 3B shows another example of a heater;

Figure 4 shows another example of a heater;

Figure 5A shows a partial cross-sectional view of a fluid flow over a heater which is not in the invention;

Figure 5B shows a partial cross-sectional view of a fluid flow over a heater according to the invention;

Figure 6A shows another example of a heater;

Figure 6B shows another example of a heater;

Figure 7A shows another example of a heater;

Figure 7B shows another example of a heater;

Figure 7C shows another example of a heater;

Figure 7D shows another example of a heater;

Figure 8 shows another example of a heater;

Figure 9 shows a cross section of an example of a heater as shown in Figure 8; and

Figure 10 shows an example of a flow chart of method steps.

Detailed

The present disclosure relates to a heater for use with an aerosol provision device. As used herein, the term “aerosol precursor material”, “vapour precursor material” or “vaporizable material” may refer to a smokable material which may for example comprise nicotine or tobacco and a vaporising agent. The aerosol precursor material is configured to release an aerosol when heated. Tobacco may take the form of various materials such as shredded tobacco, granulated tobacco, tobacco leaf and/or reconstituted tobacco. Nicotine may be in the form of nicotine salts. Suitable aerosol precursor materials 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, esters such as triacetin, triethylene glycol diacetate, triethyl citrate, glycerin or vegetable glycerin. In some examples, the aerosol precursor material is substantially a liquid that holds or comprises one or more solid particles, such as tobacco. The aerosol precursor material may be in the form of a gel. In one embodiment, the aerosol precursor material comprises a mixture of propylene Glycol vegetable glycerin. In some examples, the aerosol precursor material includes thickeners like Xanthan gum or starch.

As used herein, the term “aerosol provision device” is synonymous with “aerosol generation device” or “device” may include a device configured to heat an aerosol precursor material and deliver an aerosol to a user. The device may be portable. “Portable” may refer to the device being for use when held by a user. The device may be adapted to generate a variable amount of aerosol, which can be controlled by a user input.

As used herein, the term “aerosol” may include a suspension of vaporizable material as one or more of: solid particles; liquid droplets; gas. Said suspension may be in a gas including air. Aerosol herein may generally refer to/include a vapour. Aerosol may include one or more components of the vaporizable material.

Figure 2 shows an example of an aerosol generation device 200. The aerosol generation device 200 includes an aerosol precursor material ejector 210 comprising a chamber 202 for storing an aerosol precursor material 204 in the form of a liquid or gel (in other words, an aerosol precursor material that is suitable for being ejected through a nozzle and capable of “flowing”). The chamber 202 includes a nozzle 206 through which the aerosol precursor material 204 may be ejected. The nozzle 206 may be formed of silicone, rubber, or the like. In one example, the aerosol precursor material ejector 210 includes a piston 208 or plunger for driving the aerosol precursor material 204 out of the nozzle 206 when in use. In one example, the piston 208 is driven by a screw. In another example, the piston 208 is driven by a motor, such as an electric motor comprising solenoids. The electric motor may be coupled with a screw rod connected to the piston 208. The electric motor and position of the piston 208 may control the amount of aerosol precursor material 204 and rate at which aerosol precursor material 204 is delivered to the heater 300.

In one example, the screw rod has a relatively low thread height to reduce the power requirements of the motor. This also helps to deliver the desired amount of aerosol precursor material 204 to the heater 300 and so ensures that the process is repeatable. In one example, only a pre-determined amount (volume) of aerosol precursor material 204 is delivered to the heater 300 for aerosolization for each inhalation (or puff) of a user.

The aerosol provision device 200 also includes a heater 300 for receiving the aerosol precursor material 204 that is ejected through the nozzle 206 of the chamber 202.

The heater 300 receives the aerosol precursor material 204 on a receiving surface 302 and the aerosol precursor material 204 is configured to flow across the receiving surface 302 of the heater 300 in use. To aid the flow of the aerosol precursor material 204, the receiving surface 302 comprises one or more flow-directing structures 304 configured to direct a flow of the aerosol precursor material 204 on the receiving surface 302 of the heater. The one or more flow-directing structures 304 aids the flow of the aerosol precursor material and improves the efficiency of the system by directing the aerosol precursor material to the desired location on the receiving surface 302 of the heater 300.

This arrangement of aerosol precursor material ejector 210 and heater 300 for receiving the aerosol precursor material 204 on the receiving surface of the heater 300 enables the discharge of aerosol precursor material at high speed for a shorter initialisation and aerosolisation times for the aerosol precursor material 204. Aerosol precursor material 204 can be delivered to the heater 300 at a faster rate and be precisely controlled. A typical amount of aerosol precursor material 204 delivered to the heater for each puff would be between 0.0025ml and 0.0075ml.

In addition, most of the mechanical parts are re-usable and not thrown away after a single use. In one example, the heater 300 is arranged such that a planar portion of the receiving surface 302 is arranged in a substantially perpendicular direction to the direction of aerosol precursor material 204 being ejected from the nozzle 206 of the chamber 202. That is to say that the nozzle 206 faces the heater 300. As the heater 300 is substantially perpendicular to the flow of aerosol precursor material 204 from the nozzle 206, then it has been observed that without flow-directing structures, the aerosol precursor material 204 is not well distributed (especially if the heater 300 or chamber 202 is slightly tilted or misaligned) and the aerosol precursor material tends to flow off the heater 300. If the aerosol precursor material 204 is injected with high energy (e.g., high speed), it may spurt off heater 300, resulting in waste. The flow-directing structures reduce this waste.

In one example, as shown in Figure 3A, the one or more flow-directing structures comprises an energy breaking flow element, in particular a protrusion 304a comprising a peak 306. In use, the aerosol precursor material 204 is configured to be initially received on the protrusion 304a of the receiving surface 302 of the heater 300. In some examples, the aerosol precursor material 204 is configured to be received directly on the peak of the protrusion 304a. In one example, the protrusion 304a has a substantially dome shaped region for initially receiving the aerosol precursor material 204. That is to say that the protrusion 304a comprises a peak 306 and then may have a region that generally curves away from the peak 306. In one example, the gradient of the surface of the peak 306 is at a minimum value at the peak 306 of the protrusion 304a. The magnitude of the gradient of the surface then increases with distance from the peak to a maximum value. However, after the maximum value is reached, the gradient of the surface then decreases again.

In one example, the protrusion comprising a peak 306 may be located substantially centrally on the receiving surface 302 when viewed on plan. Other shapes are envisaged, but the example of the heater shown in Figure 3 had a substantially circular shape when viewed on plan. The heater 300 may be a cylinder. In this example, the heater 300 in the form of a cylinder may have a relatively small thickness relative to the diameter of the cylinder. In general, a circular shape of heater lowers heat and associated mechanical stresses created in rectangular design corners. In one example, the protrusion comprising a peak 306 is configured to extend from a substantially planar surface region 308 of the heater 300. In other words, the receiving surface 302 comprises a substantially planar region 308 and the one or more flowdirecting structures 304 that are raised from the substantially planar region 308.

As the aerosol precursor material 204 is configured to be initially received on the receiving surface 302 on the protrusion, then the aerosol precursor material is encouraged to start flowing on the receiving surface 302 of the heater 300 in a less turbulent manner. That is to say that the aerosol precursor material would be less likely to splash off the receiving surface 302 of the heater 300 due to the presence of the flowdirecting structure 304 in the form of a protrusion. In this example, the nozzle 206 of the aerosol generation device 200 may be substantially aligned with the protrusion 304a comprising a peak 306 of the heater 300 such that the aerosol precursor material 204 is configured to be directly received on the protrusion. In this example, the protrusion 304a comprising the peak may be positioned centrally on the heater 300 and the nozzle 206 may be aligned substantially with a central point of the heater 300.

In one example, as shown in Figure 3B, the one or more flow-directing structures 304 comprises a flow inhibiting element in particular a peripheral barrier 304b arranged at towards a periphery of the receiving surface 302. The peripheral barrier is for inhibiting the flow of the aerosol precursor material across the receiving surface 302 of the heater 300. Arranging the peripheral barrier 304b towards the periphery of the receiving surface 302 (or the heater 300) means that aerosol precursor material may be inhibited (or at least partially prevented) from flowing over a periphery of the heater 300 thereby reducing the waste of aerosol precursor material in use. In some examples, the peripheral barrier is not at an extreme edge of the heater 300, but rather inset from the edge of the heater 300.

In use, the heater 300 will provide heat to aerosolise the aerosol precursor material 204 that is located on the receiving surface 302 of the heater 300. However, the aerosol precursor material 204 will not all instantly be aerosolised as it comes into contact of the heater 300. Instead, the aerosol precursor material 204 closest to the heater 300 will likely be aerosolised first and there may be a period of time in which aerosol precursor material 204 in the form of a fluid is on the heater 300 prior to aerosolization. As such, providing flow-directing structures 304 such as the peripheral barrier 304b to prevent loss of the aerosol precursor material 204 is beneficial. It has been observed that in use, a “wave” of aerosol precursor material 204 may form on the receiving surface of the heater and so the peripheral barrier 304b may act to break this wave of aerosol precursor material 204, in use.

In some examples of the heater 300, as shown in Figure 4, the one or more flowdirecting structures 304 comprises a peripheral wall 304b as shown and described in relation to Figure 3B and the protrusion 304a as shown and described in relation to Figure 3A.

In this example, flow-directing structures 304 efficiently receive the aerosol precursor material on the receiving surface 302 of the heater 300 due to the presence of the protrusion 304a comprising a peak 306 and then reduce the flow of aerosol precursor material over an edge of the heater, thereby reducing waste.

An example of partial cross section of the aerosol generation device 200 and the heater 100 is shown in Figure 5A. In Figure 5A, the aerosol precursor material 204 is ejected through the nozzle 206 of the chamber 202, in use. The aerosol precursor material 204 is then received on a receiving surface of the heater 100, which is located at a predetermined distance from the nozzle 206 of the chamber 202. In some examples, the predetermined distance is set such that the heat transfer between the heater 300 and the chamber 202 is not significant so no high-temperature materials (e.g. high- temperature plastics materials) are required to form the chamber 202. In one example, the predetermined distance is between 0.25mm and 3mm, more particularly 0.5mm and 1 mm. However, other predetermined distances are envisaged.

In the example of the heater 100 which is not part of the invention, the aerosol precursor material 204 is liable to splash back from the surface of the heater 100 to the chamber 202 (or nozzle 206 of the chamber 202) as indicated by the arrows pointing back towards the nozzle 206 in Figure 6A.

In addition, the aerosol precursor material 204 is liable to flow off the edge of the heater 100 prior to be aerosolised leading to wasted aerosol precursor material.

In contrast, an example of the heater 300 according to the present invention is shown in Figure 5B. The heater 300 in this example is the heater 300 shown in Figure 4, with the one or more flow-directing structures 304 being in the form of a protrusion 304a comprising a peak and a peripheral barrier 304b. However, heaters 300 with only one of the protrusion 304a comprising a peak or peripheral barrier 304b may be used.

As shown in Figure 5B, the presence of the protrusion 304a comprising a peak reduces the turbulence of the flow on the receiving surface 302 of the heater and so the likelihood of the aerosol precursor material 204 splashing back on the nozzle 206 of the chamber 202 (or other parts of the chamber 202/aerosol generation device 200) is reduced. As shown in Figure 5B, the protrusion 304a comprising a peak may be substantially aligned with the nozzle 206 of the chamber 202 in use.

In addition, as shown in Figure 5B, the peripheral barrier 304b acts to direct flow of the aerosol precursor material 204 away from a periphery of the heater 300, in use, thereby reducing waste of the aerosol precursor material 204.

Figure 6A shows an example of a heater 300 comprising one or more flow directing structures in the form of a protrusion 304a comprising a peak and a peripheral wall 304b. The heater 300 shown in Figure 6A is similar to the heater shown in Figure 4 except that a height of the peripheral barrier 304b is increased. That is to say that in the example shown in Figure 4, a height of the peripheral barrier 304b is less than the height of the protrusion 304a comprising a peak. In the example of Figure 4, the peripheral barrier 304b may have a height of between 0.2mm and 0.6mm, more preferably 0.4mm.

In the example shown in Figure 6A, the height of the peripheral barrier 304b is substantially equal to the height of the protrusion 304a comprising a peak. In this example, the height of the peripheral barrier 304b may be between 0.5mm to 0.9mm, more preferably 0.7mm.

In the example shown in Figure 6B, the height of the peripheral barrier 304b is greater than the height of the protrusion 304a comprising a peak. In this example, the height of the peripheral barrier 304b may be between 1 mm to 1 ,4mm, more preferably 1 ,2mm.

Figure 7A shows another example of the heater 300. In this example, the heater 300 comprises a flow-directing structure in the form of one or more intermediate partial barriers 304c. The one or more intermediate partial barriers guide or direct the flow of the aerosol precursor material 204 on the receiving surface of the heater 300. The one or more intermediate partial barriers 304c may be located between a centre and a periphery of the receiving surface 302. in some examples, (not shown), the heater 300 only comprises flow-directing structures 304 in the form of one or more intermediate partial barriers 304c (e.g. not including one or more of the peripheral barrier 304b or the protrusion 304a comprising a peak). However, various combinations are envisaged (e.g. one or more intermediate partial barriers 304c together with the peripheral barrier 304b or one or more intermediate partial barriers 304c together with the protrusion 304a comprising a peak).

The one or more intermediate partial barriers 304c may comprise one or more passages 310 to allow the aerosol precursor material to flow. That is to say that the one or more intermediate partial barriers 304c may act to block aerosol precursor material that is flowing in a first direction, but allow aerosol precursor material flow in a second direction, through one of the passages 310.

In the example shown in Figure 7A, the heater 300 is substantially circular on plan and the one or more partial intermediate barriers 304c is in the form of a broken ring. The one or more partial barriers 304c may include a first intermediate partial barrier arranged at a first predetermined distance from the centre of the receiving surface 302. In one example, the one or more partial barriers 304c are located between the protrusion 304a comprising a central peak and the peripheral barrier 304b. In figure 7A, the intermediate partial barrier 304c is formed of four discrete barrier segments, but in other examples there may be few than four barrier segments more than four barrier segments. In the example shown in Figure 7A, the barrier segments are relatively thinner compared with the width of the peripheral barrier 304b.

Figure 7B shows an alternative example of the heater 300 comprising one or more partial intermediate barriers 304c. In this example, the one or more partial intermediate barriers 304c are approximately equal in width to the peripheral barrier 304b. Further the barrier segments are relatively short and approximately equal in length to the passages 310.

In the examples of the heater 300 shown in Figures 7A and 7B, the one or more intermediate partial barriers 304c may be formed on a concentric ring around a centre of the heater 300. Figure 7C shows an example in which there is a first intermediate partial barrier 304c1 arranged at a first predetermined distance from the centre of the receiving surface 302 and a second intermediate partial barrier 304c2 arranged at a second predetermined distance from the centre of the receiving surface 302. The second intermediate partial barrier 304c2 comprises a second set of passages 310b through which the aerosol precursor material may flow on the receiving surface 302, in use. The first intermediate partial barrier 304c1 and the second intermediate partial barrier 304c2 may be arranged concentrically.

As shown in Figure 7C, the passages 310a in the first intermediate partial barrier 304c1 may be offset from the passages 310b in the second intermediate partial barrier 304c2. In other words, the passages 310a in the first intermediate partial barrier 304c1 and the passages 310b in the second intermediate partial barrier 304c2 are arranged in such a way such that there is not a straight-line path for the aerosol precursor material 204 between the centre of the receiving surface 302 and a periphery of the receiving surface. Instead, in this arrangement the aerosol precursor material 204 follows a meandering path from the centre of receiving surface to the periphery of the receiving surface 302. Inhibiting the flow of aerosol precursor material 204 to the periphery of the receiving surface 302 means that the aerosol precursor material 204 is maintained on the receiving surface for a relatively longer period of time to increase the likelihood that it will be aerosolised by the heater 300. The offset may be radially offset and circumferentially offset (or any offset that would require the aerosol precursor material to follow a non-linear path between the part of the receiving surface 302 on which the aerosol precursor material 204 is received and the periphery of the receiving surface 302.

Figure 7D shows an example of a heater 300 as shown in Figure 7C, except the shape of the protrusion 304a is different. In figure 7D, the protrusion 304a comprises a sharp peak or point, whereas in Figure 7C, the protrusion 304a comprises a smooth peak. Other shapes of the protrusion comprising a peak are envisaged that aid the receipt of the aerosol precursor material on to the receiving surface 302. For the avoidance of doubt, the protrusion 304a as shown in Figure 7D may be used in the example of any of the heaters described herein.

Figure 8 shows another example of the heater 300. In this example, the heater 300 comprises a flow-directing structure in the form of one or more intermediate partial barriers 304c. In this example, the one or more intermediate partial barriers 304c extend along substantially radial lines. There may still be one or more passages 310 located between adjacent intermediate partial barriers 304c. In this case, there may be additional radial passages 312 in the intermediate partial barriers 304c along the radial lines from the centre of the receiving surface 302 and the periphery of the receiving surface 302. In this example, the intermediate partial barriers are elements that in some way partially blocks or guides flow in a certain direction.

Figure 9 shows a cross section through the example of the heater 300 shown in Figure 4. This example of the heater 300 shows the presence of a heating element 314 within the heater 300. In one example, the heating element 314 is a resistive element that is configured to generate heat upon a current passing therethrough. In another example, the heating element 314 comprises a susceptor that is configured to work in tandem with an inductor (not shown). The inductor is configured to generate an alternating electric field to induce a current within the susceptor, which in turn generates heat. As shown in Figure 9, the heating element 314 may be embedded within the heater 300 and located offset from the receiving surface 302 of the heater 300. The distance between the heating element 314 and the receiving surface 302 should be kept relatively low to keep heater efficiency high. In other examples, the heating element 314 may be located on the receiving surface 302 of the heater 300.

In some examples, the heater 300 comprises one or more supports 316, such as legs, that are configured to hold the heater 300 in place within the aerosol generation device 200.

In one example, at least part of the heating element 314 extends into the protrusion 304a of the receiving surface 302.

In one example, the heater 300 (and hence receiving surface) comprises a nonabsorbent material, such as non-absorbent ceramic. The non-absorbent ceramic may be cast and then machined. Lapping may potentially be used too. In other words, the heater 300 is formed of a material such that as the aerosol precursor material is received on the receiving surface and is not configured to be absorbed by any component of the heater 300 or the rest of the aerosol generation device 200.

Figure 10 shows a flowchart of an example of using the aerosol generation device. At step 400, the method includes the step of receiving an input into the device 100. At step 402, the method includes the step of ejecting aerosol precursor material 204 from the aerosol precursor material ejector 210 to the receiving surface 302 of the heater 300 upon receipt of the input. At step 404, a flow of the aerosol precursor material 204 on the receiving surface 302 of the heater 300 is directed by the one or more flowdirecting structures 304 of the receiving surface 302.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. A heater for an aerosol generation device, the heater comprising: a receiving surface for receiving an aerosol precursor material thereon, wherein the receiving surface comprises one or more flow-directing structures configured to direct a flow of the aerosol precursor material on the receiving surface of the heater.

2. The heater according to claim 1 , wherein the one or more flow-directing structures comprises a peripheral barrier arranged towards a periphery of the receiving surface.

3. The heater according to either one of claim 1 or 2, wherein the receiving surface comprises a substantially planar region and the one or more flow-directing structures are raised from the substantially planar region.

4. The heater according to any one of claims 1 , 2 or 3, wherein the one or more flowdirecting structures of the receiving surface comprises a protrusion comprising a peak, wherein the aerosol precursor material is configured to be received on the protrusion, in use.

5. The heater according to claim 4 when dependent on claim 2, wherein a height of the peripheral barrier is equal to or greater than a height of the protrusion.

6. The heater according to claims 4 or 5, where the protrusion has a substantially dome shaped region comprising the peak for receiving the aerosol precursor material.

7. The heater according to claim 6, wherein the dome shaped region comprises a region that curves away from the peak.

8. The heater according to any one of claims 4 to 7, wherein a gradient of the surface of the peak is at a minimum value at the peak of the protrusion.

9. The heater according to any one of claims 4 to 8, wherein the peak is a smooth peak.

10. The heater according to any one of claims 4 to 9, wherein the heater comprises a heating element configured to generate heat, wherein the heating element is configured to extend into the protrusion of the receiving surface.

11 . The heater according to any one of the preceding claims, wherein the one or more flow-directing structures of the receiving surface comprises one or more intermediate partial barriers located between a centre of the receiving surface and a periphery of the receiving surface.

12. The heater according to claim 11 , wherein the one or more intermediate partial barriers extend at least partially along radial lines from the centre of the receiving surface and the periphery of the receiving surface.

13. The heater according to any one of claims 11 or 12, wherein heater has a substantially circular profile and wherein the one or more intermediate partial barriers comprises a first intermediate partial barrier arranged at a first predetermined distance from the centre of the receiving surface, the first intermediate partial barrier comprising one or more first passages to permit flow of the aerosol precursor material to the periphery of the receiving surface, in use.

14. The heater according to claim 13, wherein the one or more intermediate partial barriers comprises: a second intermediate partial barrier arranged at a second predetermined distance from the centre of the receiving surface, the second intermediate partial barrier comprising one or more second passages to permit flow of the aerosol precursor material to the periphery of the receiving surface, in use.

15. The heater according to claim 14, wherein the one or more first passages are offset from the one or more second passages.

16. The heater according to any one of the preceding claims, wherein the heater comprises a non-absorbent ceramic material.

17. The heater according to any one of the preceding claims, wherein the receiving surface is a continuous surface.

18. An aerosol generation device comprising: the heater according to any one of the preceding claims; and an aerosol precursor material ejector configured to eject the aerosol precursor material to the receiving surface of the heater.

19. The aerosol generation device according to claim 18 when dependent upon claim 4, wherein the aerosol precursor material ejector comprises a chamber configured to at least temporarily store the aerosol precursor material and a nozzle through which the aerosol precursor material is ejected to the receiving surface of the heater, wherein the nozzle is substantially aligned with the protrusion of the receiving surface.

20. A method of using the aerosol generation device according to any one of claims 18 to 19, the method comprising: receiving an input into the device; ejecting aerosol precursor material from the aerosol precursor material ejector to the receiving surface of the heater upon receipt of the input, wherein a flow of the aerosol precursor material on the receiving surface of the heater is directed by the one or more flow-directing structures of the receiving surface.