Patent Description:
Electronic cigarettes, otherwise known as vapes, are becoming a popular alternative to smoking traditional tobacco cigarettes. Tobacco vapour (T-vapour) devices are a type of aerosol-generating device which heat tobacco at a lower temperature compared to traditional cigarettes. These devices are often referred to as heat not burn devices.

In T-vapour devices the vaporisable material is usually provided in the form of sticks of aerosol-generating material, usually a tobacco-containing material. These sticks are designed to be heated and not combusted as standard cigarettes are. A part of the stick comprising the aerosol-generating material can be inserted into a chamber of the aerosol-generating device which includes a heater for heating the inserted part of the stick. When heated, the aerosol generating material forms a vapour, otherwise referred to as an aerosol, which then passes through the stick and is inhaled by the user. After consumption the stick can be removed and disposed of until a next consumption of a fresh stick by a user.

Not all of the vaporised material will have chance to exit during the puff. For instance, between and after puffs the heater may still be functional for a short period of time thereby creating further aerosol that is not inhaled by the user. Problems can occur through this aerosol from the heater escaping from the heating area and entering other parts of the device. This leakage and ingress of aerosol from the heating region of the device can occur between puffs and shortly after the device has been used. Over time this can cause a build-up of residue that can cause damage to the electronics and mechanical components of the device thereby leading to malfunctions of these components. The present invention is aimed at avoiding these issues.

<CIT> discloses an aerosol generating device with sealing element.

According to a first aspect there is provided an aerosol generation device, comprising: a chamber for receiving a consumable cartridge, the consumable cartridge comprising an aerosol generating material, the chamber comprising: a first end through which the consumable cartridge is received; a second end; and an internal side wall extending from the first end to the second end, the side wall defining the chamber between the first and second ends; a sealing element located in the chamber, the sealing element configured to provide a fluidic seal between the consumable cartridge, when received in the chamber, and the internal side wall of the chamber, the sealing element comprising: a valve, the valve configured such that, flow of fluid is prevented through the valve in a direction towards the first end of the chamber.

Advantageously, the sealing element within the chamber tightly surrounds the consumable cartridge thereby providing a fluidic seal between the cartridge and the chamber. Fluid flow in the chamber may be permitted through the valve in a direction towards the second end of the chamber but prevented through the valve in a direction towards the first end of the chamber. The valve prevents the flow of fluid along the chamber (i.e. in the region surrounding the consumable cartridge) in a direction from the second end to the first end of the chamber, whereas it may allow the flow of fluid along the chamber from the first end to the second end of the chamber.

In this way, when a user takes a puff on the cartridge, air enters the device through the chamber via its first end (i.e. in the gap between the cartridge and the wall of the chamber) and passes through the valve and into a heating area before entering the consumable cartridge forcing the aerosol, generated from the aerosol generating substance, up through the cartridge and into the user's mouth. However, the remaining aerosol in the heating area is prevented from passing back up through the chamber after the puff has finished due to the seal provided by the sealing element and the one-way valve preventing flow through the chamber in that direction. As the valve acts as a one way valve it only allows the flow of fluid through the chamber towards its second end.

Advantageously, this can prevent ingress of aerosol, otherwise referred to as vapour, into the internal components of the device thereby reducing damage caused by the aerosol, particularly when the device is in a standby state between puffs and after use.

The chamber may be referred to as a cavity, i.e. it is a space in which at least part of the consumable cartridge is received. The first end of the chamber may be referred to the mouthpiece end of the chamber i.e. it is proximal to where the mouthpiece or end of the consumable cartridge which the user places in their mouth when using the device, whereas the second end of the chamber may be distal to the mouthpiece. The first end of the chamber may provide an opening in which the consumable cartridge is received.

Preferably, the sealing element is comprised of a plastic material. For instance, the sealing element may be comprised of Polyether ether ketone (PEEK). Advantageously, this enables the sealing element to withstand chemical and thermal stresses, such as high temperatures. Alternately, or in addition, the sealing element may be comprised of silicone. In other arrangements, the sealing element may be formed of any type of plastic material, ceramic, or rubber.

In some arrangements, a first axis is defined between the first and second ends of the chamber, and wherein the chamber has a width perpendicular to the first axis, wherein the sealing element has a cross section in a plane perpendicular to the first axis, the cross section having an outline that is substantially matched to the width of the chamber thereby to provide a seal between the sealing element and the internal side wall of the chamber.

In this way, the sealing element is fitted into the chamber through having a shape and size that is substantially matched to that of the chamber. This helps provide a tight fluidic seal preventing leakage of aerosol.

Preferably, the sealing element has an annular cross section in a plane perpendicular to the first axis, the annular cross section comprising an inner diameter that is configured to receive the consumable cartridge, and comprising an outer diameter that is substantially matched to the width of the chamber thereby to provide a seal between the sealing element and the internal side wall of the chamber. Advantageously, the sealing element is both matched to the size and shape of the consumable cartridge and the size and shape of the chamber. This provides a secure fluidic seal preventing leakage.

The inner diameter may be matched to the size of the consumable cartridge. The void formed by the inner diameter of the sealing element may provide a region in which the consumable cartridge is received. In other words, the sealing element may be ringed shape with the consumable cartridge housed within the centre of the ring.

In other arrangements, the sealing element may have a cross section that is a different shape to an annulus. Consumable cartridges are typically cylindrical therefore having an annulus sealing element helps ensure a tight seal. However, the chamber may have a different profile such that the outer shape of the sealing element's cross section is shaped to match the cross section of the chamber. For instance, the shape may be rectangular, hexagonal, or any other shape. In other arrangements, the inner shape of the cross section of the sealing element (i.e. the shape of the void) may be rectangular, hexagonal, or any other shape if the shape of the consumable cartridge is not cylindrical.

In some arrangements, the valve may be a check valve. In this way, by having a non-return valve ingress of aerosol may be prevented into the internal components of the device. The valve may preferably be a low pressure valve. In this way, only low pressure, such as the pressure generated by a user puffing on the device, may be required to active the valve and allow air to flow from the first to second end.

In some arrangements, the valve may be a ball check valve. The ball check valve comprising a ball that blocks the flow in one direction, whilst allowing flow in the other direction. The ball check valve may comprise a seat on which the ball sits when at rest, and a spring. The spring biases the ball such that a seal is formed around the seat. Upon air flow towards the second end of the chamber the pressure may force the ball against the spring moving the ball from the seat thereby allowing airflow only in this direction through the valve. Upon air flow towards the first end of the chamber the ball remains housed in its seat ensuring the valve remains closed, thereby preventing flow in this direction.

Alternatively, the valve may be a diaphragm check valve. The diaphragm check valve may comprise a disc or diaphragm that acts to close the valve such that it sits on a seat. Upon air flow towards the second end of the chamber the diaphragm/disc is not housed on its seat thereby allowing airflow only in this direction through the valve. Upon air flow towards the first end of the chamber the diaphragm/disc is compressed such that it forms a seal around the seat thus closing the valve, thereby preventing flow in this direction.

Preferably, the sealing element comprises a plurality of valves. The plurality of valves may be arranged and positioned around the sealing element. For instance, the plurality of valves may be positioned around a circumference of the sealing element. By having a plurality of valves this enables a high flow rate of air into the device. The circumference may be of the cross section of the sealing element. For instance, when having an annular sealing element the plurality of valves may be arranged around the circumference of the annulus. This enables uniform airflow through the valves around the chamber towards the second end of the chamber. For instance, the sealing element may comprise four valves one at each quadrant of the cross section of the sealing element. In other arrangements, the sealing element may comprise, one, two, three, five, six, eight or more valves.

Preferably the aerosol generation device further comprises a heater, wherein the sealing element is located between the first end of the chamber and the heater. The heater is configured to heat the aerosol generating material to form the aerosol. By having the sealing element located between the first end of the chamber and the heater it can prevent leakage of aerosol from the heater to prevent damage to the components of the device.

The heater may be located towards, or at, the second end of the chamber. The heater may form a heating area at the second end of the chamber. The second end of the chamber may be proximal to the heater and the first end of the chamber may be distal from the heater. The heater may be located at any position between the first and second end of the chamber. However, having the sealing element located between the heater and the first end of the chamber this prevents the aerosol formed by the heater from escaping to other internal component of the device towards the first end of the chamber.

In some arrangements, the heater may comprise an electrical resistor that can be electrically heated when electricity is supplied through the electrical connector. The electrical resistor can provide heat through Ohmic heating. In other instances, the heater may comprise an inductively energizable susceptor material. The heater may be located around the cartridge. Alternatively, the heater may be positioned within the cartridge to provide heat directly to the aerosol generating material.

Preferably, the aerosol generating device is an electronic cigarette. However, in other arrangements, the device may be a nebulizer device, or any other medical device.

Preferably, the aerosol generating device further comprises the consumable cartridge. Preferably, the consumable cartridge is removable. Alternatively, the consumable cartridge may be fixed part of the device. In this arrangement, the cartridge may be refillable or the device may be single use.

The cartridge may comprise the aerosol-generating material contained within the internal compartment. The aerosol-generating material may comprise tobacco. The aerosol-generating material may be solid or semi-solid. The aerosol-generating material may be preferably aerated tobacco mousse or equivalent foamy tobacco substrate. This may include those described in <CIT>.

For instance, they may be formed by mixing of tobacco with aerosol formers (PG, VG, <NUM> PDO). It may also be formed by mixing the tobacco and aerosol formers with flavours and/or binders. Other tobacco materials for use in a heat-not-burn system may be used. For instance those formed from reconstituted tobacco blend material mixed with aerosol formers. In other arrangements, when the aerosol generating device is for medical use, rather than an e-cigarette, the aerosol generating material may be a medicine.

In a further aspect of the invention there may be provided a sealing element configured to be located in a chamber of an aerosol generating device, the sealing element configured to provide a fluidic seal between a consumable cartridge when the consumable cartridge is received in the aerosol generating device, and the internal side wall of a chamber of the aerosol generating device in which the consumable cartridge is received, the sealing element comprising: a valve, the valve configured such that, flow of fluid is prevented through the valve in a direction towards a first end of the chamber at which the consumable cartridge is received.

<FIG> show schematic side-on cross sectional views of the top portion of a prior art heated tobacco aerosol-generating device <NUM>. A battery <NUM> is located on one side of the aerosol generating device <NUM> and a heater <NUM> located on an opposite side of the aerosol generating device <NUM>. A chamber <NUM> is present which extends from a first end <NUM> at the top of the aerosol generating device towards a second end <NUM>. The heater <NUM> surrounds the chamber <NUM> at a region towards the second end <NUM> forming a heating region <NUM>.

A cartridge <NUM>, otherwise known as a consumable or consumable cartridge, is shown located in the chamber <NUM>. The chamber <NUM> acts as a receiving portion for housing the cartridge <NUM> when the aerosol generating device <NUM> is in use. As can be seen, the cartridge <NUM> has a mouthpiece end <NUM> which protrudes out of the chamber <NUM> and a heated end <NUM> which is in the heating region <NUM> of the chamber <NUM>. The heated end <NUM> is perforated allowing airflow between the heating region <NUM> of the chamber and the cartridge <NUM>.

Electronics <NUM> are located towards the top of the aerosol generating device <NUM> above the battery <NUM>. The electronics are responsible for controlling the heater <NUM> and battery <NUM> and may provide advanced functionality such as monitoring battery level, puff counter, and other functions.

When in use the cartridge <NUM> is inserted into the aerosol generating device <NUM> such that it is located in the chamber <NUM>, as shown in <FIG>. The user then places the mouthpiece end <NUM> of the cartridge <NUM> into their mouth and inhales. External air, as indicated by reference <NUM>, is drawn into the chamber <NUM> through first end <NUM> and into the heating region <NUM>. Electronics <NUM> control battery <NUM> to power heater <NUM> such that heat is supplied to the aerosol generating material located in the cartridge <NUM> such that it forms an aerosol. The external air enters the cartridge <NUM> at its heated end <NUM> forcing the aerosol that has been generated along the cartridge <NUM> and into the user's mouth, as can be seen by reference <NUM>.

Owing to the fact that the aerosol generating device <NUM> will not stop heating immediately after the user has finished inhaling, excess aerosol will be formed that is not forced out of the cartridge <NUM> by the inhale. This aerosol is free to leak in the prior art device shown in <FIG> out from the heating region <NUM> and accumulate around electronics <NUM>, as can be seen by reference <NUM> and <NUM>. This leakage and ingress of aerosol from the heating region <NUM> of the device <NUM> can occur between puffs and shortly after the device has been used. Over time this can cause a build-up of residue that can cause damage to the electronics <NUM> and other mechanical components of the device thereby leading to malfunctions of these components. The present invention is aimed at avoiding these issues.

<FIG> show schematic side-on cross sectional views of the top portion of a heated tobacco type aerosol-generating device <NUM> according to the present invention. The aerosol-generating device <NUM> of the present invention as shown in <FIG> is identical to the aerosol generating device <NUM> of <FIG>, with the exception of having sealing element <NUM>. The same components as described above for <FIG> have the same reference numerals in <FIG>, and therefore will not be discussed in detail again here.

Sealing element <NUM>, otherwise referred to as sealing ring <NUM>, is located within chamber <NUM> just above the heating region <NUM> towards the first end <NUM> of the chamber, but below the electronics <NUM> (i.e. further from the first end <NUM> than the electronics <NUM>). <FIG> shows a schematic top down cross section of the sealing element <NUM>. As can be seen, sealing element <NUM> has an annular shape. The consumable cartridge <NUM> is located within the inner portion <NUM> formed by the sealing element, i.e. in the void or cut-out that is created.

The sealing element <NUM> has located, equally positioned around its perimeter (i.e. circumference), one-way valves <NUM>. As can be seen in <FIG> there are eight valves <NUM>. However, there may be fewer, or more valves <NUM> in other arrangements. The valves are arranged to manage the flow between the first end <NUM> and second end <NUM> of the chamber <NUM>. The valves <NUM> are one way valves, as will be described in more detail in relation to <FIG> below.

The annular shape of the sealing element <NUM> is matched to the circular cross sectional shape of the chamber <NUM>. The sealing element abuts the side wall of the chamber <NUM> thereby providing an airtight seal. The inner portion <NUM> of the sealing element is sized and shaped to the circular cross section of the cartridge <NUM> such that the sealing element abuts the consumable cartridge <NUM> thereby providing an airtight seal. As can be seen from <FIG>, the inner diameter of the annular sealing element d1 is equal to the diameter of the cartridge <NUM>. The outer diameter of the annular sealing element d2 is equal to the diameter (i.e. width) of the chamber <NUM>.

In this way, the only route for air through the chamber <NUM> is through the valves <NUM> of the sealing element <NUM>.

The sealing element <NUM> is preferably made from Polyether ether ketone (PEEK). Advantageously, this enables the sealing element <NUM> to withstand chemical and thermal stresses, such as high temperatures. Alternately, or in addition, the sealing element <NUM> may be comprised of silicone. In other arrangements, the sealing element <NUM> may be formed of any type of plastic material, ceramic, or rubber.

The cartridge <NUM> contains an aerosol forming substance, otherwise known as aerosol forming substrate, which preferably contains tobacco. In addition, it may comprise propylene glycol or glycerin which are configured to release an aerosol when heated. The aerosol-generating substrate may be an aerated tobacco mousse or equivalent foamy tobacco substrate. Alternatively, any solid or semi-solid aerosol-generating substrate may be housed within the cartridge <NUM>.

The outer body of the cartridge <NUM> is made from glass, ceramic, or polymeric material. The cartridge <NUM> has an end cap at both ends that are air permeable such that they permit the flow of air to enter and leave the cartridge <NUM>. However, in other arrangements the outer body of the cartridge <NUM> may be air permeable towards either or both ends allowing air flow into and out of the cartridge <NUM> at the ends of the cartridge <NUM>.

The function of the aerosol generating device <NUM> of the present invention will now be described. When in use the cartridge <NUM> is inserted into the aerosol generating device <NUM> such that it is located in the chamber <NUM>, as shown in <FIG>. The cartridge <NUM> is positioned through the sealing element <NUM> such that an airtight seal is present between the cartridge <NUM> and the sealing element <NUM> and the chamber <NUM> and the sealing element <NUM>. The user then places the mouthpiece end <NUM> of the cartridge <NUM> into their mouth and inhales. External air, as indicated by reference <NUM>, is drawn into the chamber <NUM> through first end <NUM> and through the valves <NUM> of the sealing element <NUM> such that it enters into the heating region <NUM>. Electronics <NUM> control battery <NUM> to power heater <NUM> such that heat is supplied to the aerosol generating material located in the cartridge <NUM> such that it forms an aerosol. The external air enters the cartridge <NUM>, which is air permeable at the heated end <NUM>, forcing the aerosol that has been generated along the cartridge <NUM> and into the user's mouth through the mouthpiece end <NUM>, as can be seen by reference <NUM>.

As outlined above, between puffs, and shortly after use, aerosol that is formed is not flushed out of the device <NUM>, and in prior art devices <NUM> as explained above in relation to <FIG> can cause ingress and damage of the internal components of the aerosol generating device <NUM>. In the present invention, as can be seen in <FIG>, the sealing element <NUM> prevents flow of this excess aerosol from travelling back up the chamber <NUM>. This is represented by reference <NUM> in <FIG>. The airtight seal provided by the sealing element both with the cartridge <NUM> and the internal walls of the chamber <NUM> prevents any backflow. Furthermore, as the valves <NUM> are one-way valves they do not permit flow towards the first end <NUM> of the chamber. This prevents any ingress of aerosol into and onto the electronic components <NUM> and other portions of the device above the heating area <NUM>.

The valves <NUM> are typically microvalves, i.e. they are of such a size that they are small enough to be housed on the sealing element <NUM>. Preferably, the valves are check valves allowing flow in only a single direction, i.e. towards the heating region <NUM> and not towards the mouthpiece end <NUM>.

<FIG> show an example of valve <NUM> for use in the sealing element <NUM> of the aerosol generating device <NUM> of the present invention. <FIG> shows a schematic outer side-view of a the valve, the valve being a ball check valve <NUM>, with <FIG> showing a schematic cross sectional side view of the valve of <FIG>.

Ball check valve <NUM> has an outer housing <NUM> having a first end <NUM> and a second end <NUM>. The outer housing <NUM> is in contact with the sealing element <NUM> in which the valve <NUM> is located forming an airtight seal between the two. Ball check valve <NUM> has a through-hole <NUM> that is located in the middle of the first end <NUM> of the valve with the surrounding portion forming a seat <NUM> on which a ball <NUM> sits. The ball <NUM> is biased into sitting in the seat by spring <NUM>. Spring <NUM> is held in place by attachment member <NUM> which attaches back onto the seat <NUM>.

Upon no external flow the ball check valve <NUM> is in the closed position as shown in <FIG>, i.e. where ball <NUM> is sitting on seat <NUM> and blocking hole <NUM>. Upon external fluid flow travelling along a direction as indicated by arrow <NUM>, (i.e. from the first end <NUM> to the second end <NUM> of the valve <NUM>) if the flow is sufficient to overcome the bias of the spring the flow causes the ball <NUM> to be displaced from the seat <NUM> thereby allowing fluid to flow through the opening <NUM> and through the ball check valve <NUM>.

Upon external fluid flow travelling along a direction as indicated by arrow <NUM>, (i.e. from the second end <NUM> to the first end <NUM> of the valve <NUM>) the seat prevents the ball <NUM> from moving such that the opening <NUM> remains blocked by the ball <NUM>.

Thus, no flow is possible in this direction. By having a spring <NUM> the valve is in a closed state upon no external flow. However, in other arrangements there may be no spring <NUM> and instead a flow in direction <NUM> may cause the valve <NUM> to close.

The ball check valve <NUM> is positioned such that the first end <NUM> of the chamber is closest to the first end <NUM>, and the second end <NUM> of the chamber is closest to the second end <NUM>. In this way, flow from the second end <NUM> of the chamber to the first end <NUM> is prevented through the ball check valve <NUM>, and flow from the first end <NUM> of the chamber to the second end <NUM> is permitted so long as the flow is strong enough to overcome the bias of spring <NUM>.

<FIG> and <FIG> show a further example valve <NUM> for use in the sealing element <NUM> shown in <FIG> and <FIG>.

<FIG> shows a schematic cross sectional side on view showing flow of air through the valve <NUM> when the valve is open, and <FIG> shows a schematic cross sectional side on view showing flow of air prevented through the valve <NUM> when the valve is closed. <FIG> shows a schematic exploded cross-sectional view of the valve of <FIG>.

The valve <NUM> shown in <FIG> and <FIG> is a diaphragm check valve <NUM>. It consists of an inlet port <NUM> and an outlet port <NUM> and diaphragm <NUM> between the two. The inlet and outlet ports each have a tube <NUM> that extends out into a junction <NUM> where they meet. The junction <NUM> formed by both the inlet and outlet ports is wider than the tubes <NUM> such that it can accommodate diaphragm <NUM>. Outlet port <NUM> also contains a seat <NUM> in the junction <NUM> on which the diaphragm <NUM> sits. The junction <NUM> has a size such that there is space for the diaphragm to move off from seat <NUM>. The diaphragm <NUM> is made of an elastomer material, such as rubber or flexible plastic this allows the shape of the diaphragm to slightly change under external pressure to aid in allowing or blocking flow.

Upon no external flow the diaphragm is in an open position and is seated on seat <NUM>. Upon external flow in a direction shown by arrow <NUM> from inlet <NUM> to outlet <NUM> the diaphragm remains in an open position and flow is permitted through channels <NUM> in the junction <NUM> such that flow <NUM> continues into flow <NUM>.

Upon external flow in in a direction shown by arrow <NUM> from outlet <NUM> to inlet <NUM> the diaphragm <NUM> flexes under the pressure of the flow such that it is displaced from seat <NUM> and is pushed against the region of the junction <NUM> connected to the input port <NUM>. This blocks the channels <NUM> preventing flow through the valve. Once the flow has stopped the diaphragm <NUM> goes back to its open position.

The diaphragm check valve <NUM> is located in sealing element <NUM>, as shown in <FIG> and <FIG>, with the input port <NUM> located towards the first end <NUM> of the chamber and the output port <NUM> located towards the second end <NUM> of the chamber. This allows flow through the diaphragm check valve <NUM> from the first end <NUM> to the second end <NUM> but prevents flow in the opposite direction.

In the device <NUM> shown in the Figures the sealing element has an annular cross section. In other arrangements, the sealing element may have a cross section that is a different shape to an annulus. Consumable cartridges are typically cylindrical therefore, having an annulus sealing element helps ensure a tight seal. However, the chamber may have a different profile such that the outer shape of the sealing element's cross section is shaped to match the cross section of the chamber. For instance, the shape may be rectangular, hexagonal, or any other shape. In other arrangements, the inner shape of the cross section of the sealing element (i.e. the shape of the void) may be rectangular, hexagonal, or any other shape if the shape of the consumable cartridge is not cylindrical.

In the Figures described above, the aerosol generating device is an electronic cigarette. However, in other arrangements, the device may be a nebulizer device or any other aerosol generating medical device.

In the above arrangements, eight valves are shown. However, in other embodiments fewer or more valves may be present. For instance, the sealing element <NUM> may have a single valve. In other arrangements, there may be two, three, four, five, six, or more valves. In addition, the valves shown above are just two example types of valves. Any other type of valve may be used that allows fluid to pass in one direction but not in the opposite direction.

In the above arrangements, the cartridge is described as being removable from the chamber. This allows the cartridge to be replaced, or refilled, when the aerosol generating material is spent. Alternatively, the cartridge may be an integral part of the aerosol generating device. In this way, the aerosol generating device may be single use, or there may be a means for refilling the aerosol generating material once it is spent.

Claim 1:
An aerosol generation device (<NUM>), comprising:
a chamber (<NUM>) for receiving a consumable cartridge (<NUM>), the consumable cartridge comprising an aerosol generating material, the chamber comprising:
a first end through which the consumable cartridge is received;
a second end; and
an internal side wall extending from the first end to the second end, the side wall defining the chamber between the first and second ends;
a sealing element (<NUM>) located in the chamber, the sealing element configured to provide a fluidic seal between the consumable cartridge, when received in the chamber, and the internal side wall of the chamber, characterized in that the sealing element comprises:
a valve (<NUM>), the valve configured such that, flow of fluid is prevented through the valve in a direction towards the first end of the chamber.