Aerosol Provision Device

The present application is a continuation application of U.S. patent application Ser. No. 17/596,294 filed Dec. 7, 2021, which is a National Phase entry of PCT Application No. PCT/EP2020/065886, filed Jun. 8, 2020, which claims priority from GB Patent Application No. 1908194.2, filed Jun. 7, 2019, each of which is hereby fully incorporated herein by reference.

The present disclosure relates to an aerosol provision device, a method of generating an aerosol using the aerosol provision device, and an aerosol-generating system comprising the aerosol provision device.

Articles such as cigarettes, cigars and the like burn tobacco during use to create tobacco smoke. Attempts have been made to provide alternatives to these types of articles, which burn tobacco, by creating products that release compounds without burning. Apparatus is known that heats smokable material to volatilize at least one component of the smokable material, typically to form an aerosol which can be inhaled, without burning or combusting the smokable material. Such apparatus is sometimes described as a “heat-not-burn” apparatus or a “tobacco heating product” (THP) or “tobacco heating device” or similar. Various different arrangements for volatilizing at least one component of the smokable material are known.

The material may be, for example, tobacco or other non-tobacco products or a combination, such as a blended mix, which may or may not contain nicotine.

According to a first aspect of the present disclosure, there is provided an aerosol provision device for generating aerosol from aerosol-generating material, the device comprising: a heating chamber for receiving the aerosol-generating material; at least one heating unit for heating the aerosol-generating material during a session of use; and an aperture, which fluidically connects the heating chamber with the exterior of the aerosol provision device; wherein the aperture is non-circular and has a smallest dimension, as measured through the centroid of the aperture, of less than or equal to 0.65 mm.

According to a second aspect of the present disclosure, there is provided an aerosol provision device for generating aerosol from aerosol-generating material, the device comprising: a heating chamber for receiving the aerosol-generating material; at least one heating unit for heating the aerosol-generating material during a session of use; and an aperture, which fluidically connects the heating chamber with the exterior of the aerosol provision device; wherein the aperture has a perimeter of less than or equal to 3.40 mm.

According to a third aspect of the present disclosure, there is provided an aerosol provision device for generating aerosol from aerosol-generating material, the device comprising: a housing; a heating chamber, located within the housing, for receiving the aerosol-generating material; at least one inductive heating unit for heating the aerosol-generating material during a session of use; and an aperture, which fluidically connects the heating chamber with the exterior of the aerosol provision device; wherein the aperture has an area of less than or equal to 0.65 mm.

According to a fourth aspect of the present disclosure, there is provided an aerosol provision device for generating aerosol from aerosol-generating material, the device comprising: a housing; a heating chamber, located within the housing, for receiving the aerosol generating material; at least one inductive heating unit for heating the aerosol-generating material during a session of use; and a plurality of apertures, the or each fluidically connecting the heating chamber with the exterior of the aerosol provision device; wherein the plurality of apertures has a total combined area of less than 4.00 mm.

Further features and advantages of the invention will become apparent from the following description of preferred embodiments of the invention, given by way of example only, which is made with reference to the accompanying drawings.

To facilitate formation of an aerosol in use, aerosol-generating material for aerosol-provision devices (e.g. tobacco heating products) usually contains more water and/or aerosol-generating agent than the smokeable material within combustible smoking articles. This higher water and/or aerosol-generating agent content can increase the risk of condensate collecting within the aerosol-provision device during use, particularly in locations away from the heating unit(s).

The inventors consider that this problem may be greater in devices with enclosed heating chambers. In some such devices, the heating chamber may be fluidically connected, in parallel, with the exterior of the device by several apertures, which may, for example, regulate the flow of air into the device.

Having studied the results of tests of devices having such apertures, the inventors consider that the apertures may be a significant contributing factor to the collection of condensate within the device. Furthermore, the inventors foresee a risk that any condensate that does accumulate within the device may leak out through the apertures, with such leakage inconveniencing the user of the device.

However, the inventors have determined that suitably configured apertures may reduce the risk of such leakage of condensate from the device.

In this regard, reference is directed to, which is a front view of an example of an aerosol provision devicefor generating aerosol from an aerosol-generating medium/material. In broad outline, the devicemay be used to heat a replaceable articlecomprising the aerosol-generating medium, to generate an aerosol or other inhalable medium which is inhaled by a user of the device.

The devicecomprises a housing(in the form of an outer cover) which surrounds and houses various components of the device. The devicehas an openingin one end, through which the articlemay be inserted for heating by a heating assembly. In use, the articlemay be fully or partially inserted into the heating assembly where it may be heated by one or more components of the heater assembly.

depicts a cross-sectional view of the heating assembly and neighboring components within the deviceof. As shown, the deviceincludes a heating chamberfor receiving the aerosol-generating material. The deviceadditionally includes a number of apertures. As is apparent, the aperturesfluidically connect, in parallel, the heating chamberwith the exterior of the device.

Aperturesmay provide suitable impedance to the flow of air into the device, so as to regulate the flow of air through the device. However, such impedance may equally increase the risk that condensate collects within the device, for example in inlet conduit. Additionally, as mentioned above, there is a risk that such accumulated condensate leaks from the device, inconveniencing the user. Nonetheless, by configuration of the device, in accordance with any of the aspects of this disclosure, the risk of condensate leaking from the devicemay be substantially reduced.

As also shown in, the deviceincludes two heating units,for heating the aerosol-generating material. Although the illustrated example includes two heating units,, it should be understood that this is by no means essential and the devicecould include only one heating unit, or could include three or more heating units, as appropriate.

The inventors have studied the results of tests of devices of similar construction to the deviceof. Based on these test results, the inventors foresee a particular risk that condensate collects within the device. A possible contributing factor is that, in many cases, for condensate-forming substances to exit the devicewould involve them travelling in the opposite direction to the flow of air through the aperturesand into the deviceduring use. An additional contributing factor is that the apertures, which fluidically connect the inlet conduitwith the exterior of the device, offer resistance or impedance to the flow of air into the device, so as to regulate the flow of air through the device; however, such resistance/impedance hinders the exit of condensate-forming substances from the inlet conduit, through the apertures.

Moreover, as noted above, where condensate does accumulate within the device, there is a risk that it leaks out of the device, inconveniencing the user.

Nonetheless, by studying the test results, the inventors believe that they have determined suitable approaches for configuring the aperturesto reduce the risk of condensate leaking from the device.

According to a first approach, the aperturesof the devicemay be configured so as to be non-circular and to each have a smallest dimension (as measured through the centroid of the aperture in question) of less than or equal to 0.65 mm. Testing indicates that devices with such apertures are effective at preventing the leakage of condensate.

Without wishing to be bound by the theory, it is hypothesized that the fluidic resistance forces that inhibit condensate from passing through a given aperture may, in at least some cases, be related to the smallest dimension of the aperture, for example because this smallest dimension is indicative of capillary forces. A device having non-circular apertures with a smallest dimension of less than or equal to 0.65 mm may therefore, potentially as a result of such capillary forces, provide a suitable level of impedance to retain condensate within the device. On the other hand, the aperture's other dimensions may be selected so as to provide a suitable area for the aperture, for example so as to achieve a desired level of impedance to air flow.

Based on experimental results, the inventors consider that, in many cases, a smallest dimension of less than or equal to 0.625 mm may be sufficient to cause a significant reduction in the risk of leakage of condensate. Nonetheless, in some cases, the apertures may be configured with a smallest dimension of less than or equal to 0.60 mm.

According to a second approach, the aperturesof the devicemay be configured so as to have a perimeter of less than or equal to 3.40 mm. Testing indicates that devices with such apertures are effective at preventing the leakage of condensate. Again, without wishing to be bound by the theory, it is hypothesized that, in many cases, the frictional forces experienced by liquid passing through a given aperture may be related to the perimeter of the aperture. Accordingly, apertures with relatively small perimeters may be effective at preventing the leakage of condensate.

Based on experimental results, the inventors consider that, in many cases, a perimeter of less than or equal to 3.40 mm may be sufficient to cause a significant reduction in the risk of leakage of condensate. Nonetheless, in some cases, the apertures may be configured with a perimeter of less than or equal to 3.25 mm, in other cases less than or equal to 3.00 mm.

According to a third approach, the aperturesof the device may be configured so as to have an area of less than or equal to 0.65 mm. Testing indicates that devices with such apertures are effective at preventing the leakage of condensate. Again, without wishing to be bound by the theory, it is hypothesized that the ability of liquid to pass through a given aperture may be inversely related to the area of that aperture because, where a given pressure is present within a liquid (e.g. as a result of gravity), and that pressure is applied over a smaller area, a smaller total force is imparted on the fluid. Accordingly, apertures with relatively small areas may be effective at preventing the leakage of condensate.

Based on experimental results, the inventors consider that, in many cases, an area of less than or equal to 0.65 mmmay be sufficient to cause a significant reduction in the risk of leakage of condensate. Nonetheless, in some cases, the apertures may be configured with an area of less than or equal to 0.60 mm, in other cases less than or equal to 0.55 mm.

It will be appreciated that combinations of the above approaches may be employed when configuring a given aperture. For example, apertures might be configured so as to each have a smallest dimension of less than or equal to 0.65 mm and/or a perimeter of less than or equal to 3.40 mm and/or an area of less than or equal to 0.65 mm.

Returning now to, it may be noted that, in the particular example device shown, the heating units,are inductive heating units. Inductive heating units may provide rapid heating of aerosol-generating material. However, the inventors consider such rapid heating may be a risk factor for the accumulation of condensate, for example because inductive heating units may generate condensate-forming substances at a greater rate than they can be carried away through apertures.

In the particular example deviceshown in, each inductive heating unit,comprises a respective coil,and a respective heating element,. In the particular example shown, the electrically-conductive heating elements,of the two heating units,correspond to respective sections of a single metal tube. However, in other examples, each heating element may be a separate and distinct structure.

In general, the coil of an inductive heating unit may, for example, be configured to cause heating of one or more electrically-conductive heating elements, for instance so that heat energy is conductible from such electrically-conductive heating elements to aerosol-generating material to thereby cause heating of the aerosol-generating material. An inductive heating unit may be configured to cause the coil to generate a varying magnetic field for penetrating the at least one heating element, to thereby cause induction heating of the at least one heating element. In the deviceshown in, the coil,of each inductive heating unit,causes heating of its corresponding electrically-conductive heating element,. Each heating element,then conducts heat to the aerosol-generating material

As will be appreciated, heating units other than induction heating units might be employed in other examples. For instance, the device might include one or more resistive heating units. As an example, a resistive heating unit could be substituted for each of inductive heating units,. A resistive heating unit may comprise (or consist essentially of) one or more resistive heating elements. By “resistive heating element”, it is meant that on application of a voltage to the element, current flows within the element, with electrical resistance in the element transducing electrical energy into thermal energy which heats the aerosol-generating substrate. A resistive heating element may, for example, be in the form of a resistive wire, mesh, coil and/or a plurality of wires. The heat source may be a thin-film heater.

As is also apparent from, the particular deviceshown additionally includes an inlet conduit, which fluidically connects the heating chamberwith the exterior of the device. During use, air may be drawn into the device, through the apertures, before flowing along inlet conduitand later into heating chamber. Thus, the aperturesfluidically connect, in parallel, the inlet conduit(as well as heating chamber) with the exterior of the device.

It may additionally be noted that, in the specific example shown in, the distal end of the inlet conduitis adjacent the aperturesand thus each apertureopens, on one side, to the distal end of the inlet conduit, and, at an opposite side, to the exterior of the device.

Reference is now directed towhich is a plan view of the part of the devicein which aperturesare formed; that part of the device is a door but it could be any other component.

In the particular example shown, the deviceincludes six apertures. However, any suitable number of apertures could be included as a plurality of apertures; for instance, some embodiments might have as few as four apertures, whereas other embodiments might have as many as eight or ten apertures. Alternatively, a single aperture could be provided.

As illustrated in, the aperturesmay be distributed circumferentially about a longitudinal axisof the inlet conduit. More particularly, the aperturesare arranged in a ring-shaped array. In the example shown, the center of the ring-shaped array is defined by an axisof the inlet conduit, optionally a longitudinal axis of the inlet conduit.

As is apparent from, in the particular example shown, the aperturesare spaced substantially equidistantly. This may, for example, ensure a smooth and stable flow of air into the device. However, this is by no means essential and in other embodiments groups of the aperturescould be clustered together.

As is also apparent from, each aperturehas a largest dimension, as measured through the centroid of the aperture, that is directed generally circumferentially (i.e. it lies in a direction that is closer to a circumferential direction than to a radial direction, as defined relative to the longitudinal axisof the inlet conduit). Such an arrangement may, for example, tend to cause in-flowing air to adopt a helical flow pattern, which may, in some cases, lead to a smooth and stable flow of air into the device. The largest dimensionmay be less than or equal to 1.20 mm, as measured through the centroid of the aperture.

It may further be noted that each of the aperturesis shaped as a regular polygon. However, in other embodiments the aperturescould be shaped as irregular polygons.

Furthermore, while each aperturein the device of may have substantially the same shape, this is by no means essential and in other embodiments two or more groups of apertures could be provided, where all the apertures in a group have substantially the same shape. Where there is only one aperture, it could be shaped as described above.

Reference is next directed to, which illustrate various features of the construction and operation of the devices of.

Turning first to, as shown, the devicemay comprise a first end memberwhich comprises a lidwhich is moveable relative to the first end memberto close the openingwhen no articleis in place. In, the lidis shown in an open configuration, however the lidmay move into a closed configuration. For example, a user may cause the lidto slide in the direction of arrow “A”.

The devicemay also include a user-operable control element, such as a button or switch, which operates the devicewhen pressed. For example, a user may turn on the deviceby operating the switch.

The devicemay also comprise an electrical component, such as a socket/port, which can receive a cable to charge a battery of the device. For example, the socketmay be a charging port, such as a USB charging port.

depicts the deviceofwith the outer coverremoved and without an articlepresent. The devicedefines a longitudinal axis.

As shown in, the first end memberis arranged at one end of the deviceand a second end memberis arranged at an opposite end of the device. The first and second end members,together at least partially define end surfaces of the device. For example, the bottom surface of the second end memberat least partially defines a bottom surface of the device. Edges of the outer covermay also define a portion of the end surfaces. In this example, the lidalso defines a portion of a top surface of the device.

The end of the device closest to the openingmay be known as the proximal end (or mouth end) of the devicebecause, in use, it is closest to the mouth of the user. In use, a user inserts an articleinto the opening, operates the user controlto begin heating the aerosol-generating material and draws on the aerosol generated in the device. This causes the aerosol to flow through the devicealong a flow path towards the proximal end of the device.

The other end of the device furthest away from the openingmay be known as the distal end of the devicebecause, in use, it is the end furthest away from the mouth of the user. As a user draws on the aerosol generated in the device, the aerosol flows away from the distal end of the device.