WO2023186596A1

WO2023186596A1 - Vapour generating systems

Info

Publication number: WO2023186596A1
Application number: PCT/EP2023/057037
Authority: WO
Inventors: Alec WRIGHT; Peter LOVEDAY
Original assignee: Jt International Sa
Priority date: 2022-04-01
Filing date: 2023-03-20
Publication date: 2023-10-05

Abstract

An aerosol generating system comprises a cartridge (2) that contains a supply of aerosol generating material (15) and an aerosol generating device (4) for receiving the cartridge (2). When the cartridge (2) is received in the aerosol generating device (4), a continuous conductive path is formed from discrete conductive elements (34,36) alternately located on the cartridge (2) and the device (4). The continuous conductive path may form part of a test circuit for verifying the correct insertion of an authentic cartridge (2) or part of a power circuit required to operate an aerosol generator (22). Preferably the conductive elements (34) on the cartridge (2) are located on projections (38) or in recesses (28) in the shapes of letters, symbols or other patterns capable of conveying visual information, for example a trade mark of the supplier of authentic cartridges (2).

Description

VAPOUR GENERATING SYSTEMS

Technical Field

The present disclosure relates generally to aerosol generating systems configured to convert a liquid or other material into an aerosol for inhalation by a user of the system. More specifically, it relates to ensuring that aerosol generating devices may only be used with authorized aerosol generating cartridges.

Technical Background

The term aerosol generating system (or more commonly electronic cigarette or e-cigarette) refers to handheld electronic apparatus that is intended to simulate the feeling or experience of smoking tobacco in a traditional cigarette. Electronic cigarettes typically work by heating an aerosol generating material to generate a vapour that cools and condenses to form an aerosol which is then inhaled by the user. Accordingly, the use of e-cigarettes is also sometimes referred to as “vaping”. The aerosol generating material is most commonly a liquid comprising nicotine, propylene glycol, glycerine and flavourings. However, solid or semi-solid aerosol generating materials are also known.

Typical e-cigarettes comprise vaporizing units, i.e. systems or sub-systems for vaporizing the aerosol generating liquid by utilizing a heating element to produce vapour from liquid stored in a capsule, tank or reservoir. When a user operates the e- cigarette, liquid from the reservoir is transported through a liquid transfer element, e.g. a cotton wick or a porous ceramic block, and is heated by the heating element to produce a vapour, which cools and condenses to form an aerosol that can be inhaled. To facilitate the ease of use of e-cigarettes, removable cartridges are often employed. These cartridges are often configured as “cartomizers”, which means an integrated component comprising a liquid store, a liquid transfer element and a heater. Electrical connectors may also be provided to establish an electrical connection between the heating element and a power source. Such cartridges may be disposable, i.e. not intended to be capable of reuse after the supply of liquid in the reservoir has been exhausted. Alternatively, they may be reusable, being provided with means allowing the reservoir to be refilled with a new supply of vapour generating liquid.

By using alternative technologies such as jet heads or nebulizers, it may be possible to generate droplets directly from the liquid, which are of a suitable size to form an aerosol without the need to go through the intermediate stage of forming a vapour and perhaps without heating the liquid at all. The use of such technologies is not excluded from the application of the present invention, which, in its broadest scope, is applicable to any aerosol generating system in which a replaceable cartridge is connected to an aerosol generating device, wherein the cartridge supplies an aerosol generating material and the device supplies an electrical current used for generating an aerosol from the material.

A cartridge for an e-cigarette typically comprises an air inlet at a first end and an air outlet at a second, opposite end. (Considered from the viewpoint of a user of the system, the first end of the cartridge may also be termed the distal end and the second end of the cartridge may also be termed the proximal end or mouth end.) The first end of the cartridge is configured to be releasably connected to a main body of the aerosol generating system, which may, for example, contain a power source and control electronics. A user inhales through a mouthpiece at the second end of the cartridge to draw air along an airflow path from the air inlet to the air outlet. The airflow path passes through an aerosol generating chamber, where vapour or droplets formed from the liquid are mixed with the air to form an aerosol.

In use, such a cartridge is received in an aerosol generating device to form the complete aerosol generating system. The aerosol generating device is typically not disposable, i.e. it is intended to be re-used multiple times with different cartridges. The device comprises a body by which it may be held by a user and contains a source of power for the heater in the cartridge, as well as control circuitry. The device may further comprise means such as buttons for the user to input commands to the aerosol generating system and/or means such as lights or a display screen for the system to output information to the user. Additionally or alternatively, the device may comprises means for communicating with an external device, such as a mobile phone, which provides an interface for the user to interact with the aerosol generating system.

There exists a desire that certain aerosol generating devices should be capable of use only with authentic cartridges, which originate from or are authorized by the manufacturer or supplier of the device. This is not only to protect the supplier’s market in the sale of replacement cartridges. It also allows the supplier to ensure that the device is able to control the operation of the cartridge in an appropriate way, which complies with accepted safety standards for the user (e.g. relating to the operating temperature of the cartridge and the substances contained in the aerosol that is generated) and does not risk damage to the device itself (e.g. by drawing excess current from the power supply or by leakage of aerosol generating liquid from a poorly designed cartridge). Preferably, a system that allows an aerosol generating device to detect or disable inauthentic cartridges, would also allow such inauthentic cartridges to be detected by visual inspection by humans.

A prior art aerosol generating system that is capable of detecting an inauthentic cartridge is disclosed in Chinese utility model CN 212306822 U. Authentication of the cartridge is performed by a camera assembly in the device, which records an “anti-fake sign indicating number” on a mating face of the cartridge. The provision of a camera and of software that is capable of identifying whether the imaged number represents an authentic cartridge would add significantly to the cost of the device. A cheaper and simpler system is therefore desirable.

Summary of the invention

The invention provides an aerosol generating system comprising a cartridge that contains a supply of aerosol generating material, and an aerosol generating device for receiving the cartridge; wherein the cartridge comprises a first set of multiple discrete conductive elements and the aerosol generating device comprises a second set of multiple discrete conductive elements, the first and second sets of conductive elements being configured such that, when the cartridge is received in the aerosol generating device, the first set of conductive elements comes into contact with the second set of conductive elements to form a continuous conductive path comprising conductive elements alternately from the first and second sets.

Because the continuous conductive path is formed from multiple conductive elements alternately from the first set of elements in the cartridge and second set of elements in the device, the path will be formed only if the patterns of the first and second sets of elements are complementary to one another. This provides a way of ensuring that with any given aerosol generating device, only cartridges that comprise a complementary set of conducting elements can be used. If an inauthentic cartridge with a different pattern of conducting elements is used, a circuit via the conductive path will not be completed. Thereby, if the circuit is used to power the generation of an aerosol, the system will be unable to operate with the inauthentic cartridge. Alternatively, the device may use the circuit to test the cartridge, whereby the insertion of an inauthentic cartridge can be detected and appropriate action can be taken, such as disabling it.

While disposing multiple conductive elements in a particular pattern will add somewhat to the complexity and cost of assembling the device and the cartridge, these are simple mechanical/electrical components that can be easily integrated into a conventional assembly process. The invention does not require the addition of expensive components such as cameras or significant additional software or processing power.

In a first group of embodiments of the invention, the aerosol generating device comprises a plurality of projections, the conductive elements of the second set being formed on the projections; and the cartridge comprises a plurality of recesses configured to receive the projections when the cartridge is received in the aerosol generating device, the conductive elements of the first set being formed to extend between the recesses. The projections of the device and the recesses of the cartridge may thereby form a pattern of interdigitating parts that reflects the complementary patterns of the first and second sets of conductive elements. This provides for positive engagement between the cartridge and the device and implies that the distinctive pattern of the first set of conducting parts in the cartridge may be reflected in the pattern of the recesses, so as to be visually apparent to a human observer. In such embodiments, the cartridge may further comprise a layer of non-conductive material, which covers surfaces of the first set of conductive elements that face towards the aerosol generating device. In this way, at least part of the conductive material that forms the surface of the conductive elements may be hidden from the exterior of the cartridge. This may protect it and it also allows a much wider choice of non-conductive materials, e.g. plastics, to be used to determine the external physical properties and appearance of the cartridge. The appearance of the non-conductive material may be chosen to make more visually apparent the pattern of the recesses, which reflects the authentic character of the cartridge.

Preferably, in such embodiments of the invention, the recesses in the cartridge are in the shapes of letters, symbols or other patterns capable of conveying visual information to a human observer. From the information conveyed by the pattern of recesses, the observer can easily recognize whether or not the cartridge is genuine. For example, the pattern might be a distinctive name, logo or other sign by which the supplier of authentic cartridges is recognized. This example provides the further advantage that such a sign can often be legally protected as a registered trade mark or through other intellectual property rights such as copyright. Therefore, in order for a competing manufacturer to supply inauthentic cartridges that are capable of operating with a genuine device, that manufacturer must necessarily form the first set of conducting elements between a pattern of recesses in the cartridge that replicates the protected sign. Intellectual property laws can thereby be used to prevent the distribution and sale of the inauthentic cartridges.

In a second, alternative, group of embodiments of the invention, the cartridge comprises a plurality of projections, the conductive elements of the first set being formed on the projections; and the aerosol generating device comprises a plurality of recesses configured to receive the projections when the cartridge is received in the aerosol generating device, the conductive elements of the second set being formed to extend between the recesses. The projections of the cartridge and the recesses of the device may thereby form a pattern of interdigitating parts that reflects the complementary patterns of the first and second sets of conductive elements. This provides for positive engagement between the cartridge and the device and implies that the distinctive pattern of the first set of conducting parts in the cartridge may be reflected in the pattern of the projections, so as to be visually apparent to a human observer.

In this group of embodiments, the aerosol generating device may further comprise a layer of non-conductive material, which covers surfaces of the second set of conductive elements that face towards the cartridge. In this way, at least part of the conductive material that forms the surface of the conductive elements may be hidden from the exterior of the device. This may protect it and it also allows a much wider choice of non-conductive materials, e.g. plastics, to be used to determine the external physical properties and appearance of the device. The non-conductive covering layer also provides the advantage that a sheet or strip of conductive material cannot simply be laid across the surfaces of the second set of conductive elements that face towards the cartridge and thereby provide a conductive path between them without replicating the distinctive pattern of projections in the cartridge that would be necessary to engage with the second set of conductive elements within the recesses of the device.

Preferably, in such embodiments of the invention, the projections on the cartridge are in the shapes of letters, symbols or other patterns capable of conveying visual information. From the information conveyed by the pattern of proj ections, the observer can easily recognize whether or not the cartridge is genuine. For example, the pattern might be a distinctive name, logo or other sign by which the supplier of authentic cartridges is recognized. This example provides the further advantage that such a sign can often be legally protected as a registered trade mark or through other intellectual property rights such as copyright. Therefore, in order for a competing manufacturer to supply inauthentic cartridges that are capable of operating with a genuine device, that manufacturer must necessarily form the first set of conducting elements between a pattern of recesses in the cartridge that replicates the protected sign. Intellectual property laws can thereby be used to prevent the distribution and sale of the inauthentic cartridges. In some embodiments of the invention, the aerosol generating device comprises a source of electrical power, the cartridge or the aerosol generating device comprises an electrically powered aerosol generator; and the continuous conductive path forms part of a circuit for supplying power from the source to the aerosol generator. Accordingly, if the device is used with an inauthentic cartridge, such that the first set of conductive elements in the cartridge is not in a pattern complementary to the second set in the device, a continuous conductive path will not be formed and power cannot be delivered to the aerosol generator. It follows that the inauthentic cartridge will automatically be prevented from being used with the device to generate an aerosol.

The aerosol generator may be an electrically powered heater in the disposable cartridge. This is a conventional arrangement, which means that the aerosol generating material, which may be liquid or solid, can remain within the cartridge. The heater needs to be replaced with each new cartridge but a simple resistive or inductive electrical heater need not be an expensive component. Alternatively, the aerosol generator may be located within the housing of the reusable device. This provides the advantage that the generator does not need to be replaced with each new cartridge so it may be more suitable for more complex aerosol generating technologies, such as nebulization for example. On the other hand, where the aerosol generating is a fluid substance that needs to flow from the cartridge to the device, a sealing arrangement may additionally be required between them and/or a controlled, leak-free liquid delivery system to the aerosol generator to avoid an associated risk of leakage at the junction or inside the housing of the device.

In other embodiments of the invention, the continuous conductive path forms part of a test circuit, through which the aerosol generating device can supply current to verily the correct insertion of the cartridge and/or the authenticity of the cartridge. Accordingly, if the device is used with an inauthentic cartridge, such that the first set of conductive elements in the cartridge is not in a pattern complementary to the second set in the device, a continuous conductive path will not be formed through the test circuit. If a control circuit in the device does not detect the flow of current through the test circuit it can determine that the cartridge is not authentic or that it has not been inserted correctly and it can take appropriate action, such as disabling the supply of power to the cartridge and/or generating a warning to the user.

The test circuit is not necessarily distinct from the circuit for supplying power to the heater. If a common circuit is used then, when the cartridge has been inserted into the device, the control circuit would first attempt to send a small test current through the test/power circuit in order to confirm whether the cartridge is authentic and has been inserted correctly. Only if those conditions are satisfied will the control circuit deliver the higher current required to power the heater.

In an aerosol generating system according to the invention, in which the continuous conductive path forms part of a test circuit, the device may further comprise means for determining whether current is flowing through at least one intermediate conductive element of the second set. By “intermediate” is meant a conductive element that is not the first or last in the set, according to their sequence measured in series along the conductive path. The means for determining whether current is flowing may be means for measuring a voltage at the intermediate conductive element. In the event that current is determined to be flowing through the test circuit but not through the one or more intermediate elements, it may indicate that the cartridge is designed to bypass parts of the conductive path and is not authentic.

Preferably, a plurality of the conductive elements of the first set and a plurality of the conductive elements of the second set he in a common plane. This facilitates the manufacture of both the device and the cartridge. Whether the conductive elements are assembled as individual components or whether they are laid down in a process of deposition, it will be simpler to carry out that manufacturing step if as many of the elements as possible he in a common plane. Additionally, the cartridge typically comprises an exterior surface that faces the device in use. If the conductive elements of the first set lie in a plane that either forms that surface or is parallel to it, then this provides a further advantage that the pattern of the conductive elements in the first set is able to be seen and distinguished by a human observer, as discussed above. The conductive elements of the first set may lie in a first plane and the conductive elements of the second set may he in a second plane, such that when the projections are received in the recesses the edges of the conductive elements of the first and second sets are brought into contact with each other. This facilitates a compact connection between the recesses and projections, and can also provide a further advantage in that the pattern of the conductive elements in the first set is able to be seen and distinguished by a human observer, as discussed above.

The invention further provides a method of activating an aerosol generating system that comprises a cartridge containing a supply of aerosol generating material and comprising a first set of discrete conductive elements, and an aerosol generating device comprising a second set of discrete conductive elements; the method comprising receiving the cartridge in the aerosol generating device such that the first set of conductive elements comes into contact with the second set of conductive elements to form a continuous conductive path comprising conductive elements alternately from the first and second sets. As previously explained, this ensures that with any given aerosol generating device, only authentic cartridges that comprise a complementary set of conducting elements can be used, otherwise the continuous conductive path will not be formed.

The step of forming the continuous conductive path may complete an electric circuit that connects a heater in the cartridge to a source of power in the aerosol generating device. In that case, if an inauthentic cartridge is inserted, the continuous conductive path will not be formed and power cannot be supplied to the cartridge.

Alternatively, the step of forming the continuous conductive path may complete a test circuit, in which case the method further comprises supplying current through the test circuit to verify the correct insertion of the cartridge or the authenticity of the cartridge. In the event that the an inauthentic cartridge is detected, a warning may be issued and/or its use may be disabled by the device.

In this specification, “authentication” or “verification” is the process of determining whether a cartridge received in the aerosol generating device is an authentic cartridge according to criteria determined by the manufacturer or supplier of the device. The outcome of authentication or verification may accordingly be positive or negative.

Description of the drawings

Figure 1 is a schematic diagram of an aerosol generating system according to the prior art, of a kind with which the present invention may be used.

Figure 2 is a schematic section through a cartridge and part of a device according to a first embodiment of the invention, before insertion of the cartridge into the device.

Figure 3 is an end view of the cartridge of Fig. 2.

Figure 4 is an end view of the device of Fig. 2.

Figure 5 is a schematic section, similar to Fig. 2, after the cartridge has been inserted into the device.

Figures 6 and 7 are schematic sections of a detail of an aerosol generating system according to the present invention, showing alternative arrangements for contact between first and second sets of conductive elements.

Figure 8 is a schematic section through a cartridge and part of a device according to a second embodiment of the invention, before insertion of the cartridge into the device. Figure 9 is an end view of the cartridge of Fig. 8.

Figure 10 is an end view of the device of Fig. 8.

Figure 11 is a schematic section, similar to Fig. 8, after the cartridge has been inserted into the device.

Figure 12 is a schematic section through a cartridge and part of a device according to a third embodiment of the invention, before insertion of the cartridge into the device. Figure 13 is an end view of the cartridge of Fig. 12.

Figure 14 is an end view of the device of Fig. 12.

Figure 15 is a schematic section, similar to Fig. 12, after the cartridge has been inserted into the device.

Figure 1 illustrates the general arrangement of an aerosol generating system, of a kind with which the present invention may be used. The system comprises a replaceable cartridge 2, which is removably attached to or received in an aerosol generating device 4. The aerosol generating device 4 comprises a housing 6, which contains a power source 8, such as a rechargeable battery, and a control circuit 10, which receives power from the power source 8 and selectively delivers it to a pair of electrical terminals 12 facing the cartridge 2. The device 4 may further comprise components that are not illustrated, including (without limitation) any or all of the following:

• buttons, switches or a touch-sensitive screen on the exterior of the housing 6, by which the user can input commands to the aerosol generating system;

• indicator lights or a display screen on the exterior of the housing 6, by which the aerosol generating system can output information to the user;

• communication means, e.g. a port or a wireless antenna, by which the aerosol generating system can exchange data with an external device such as a user’s mobile phone or a manufacturer’s customer support system.

The cartridge 2 is engaged with the aerosol generating device 4, to which it may be removably secured by magnetic and/or mechanical means (not illustrated) such as magnets, clips, a bayonet and/or screw fitting. The cartridge 2 may be fitted onto the housing 6 of the device 4 in an end-to-end arrangement as shown, or it may be received in a cavity in the housing 6, for example behind a cover (not illustrated).

The cartridge 2 comprises a reservoir 14, which contains a supply of aerosol generating liquid 15. The cartridge 2 further comprises an airflow path 16 from an air inlet 18 to a mouthpiece 20. The mouthpiece 20 may be integral with the cartridge 2, may be removably attached to the cartridge 2 or, in systems in which the cartridge 2 is received inside the housing 6 of the device 4, the mouthpiece 20 may form part of the device 4.

The cartridge 2 further comprises electrically powered means for generating an aerosol from the liquid 15. In the illustrated embodiments of the invention, the aerosol generator comprises a simple resistance heater 22 with a coil wrapped around a liquid- permeable wick 23. The heater 22 is disposed in the airflow path 16, possibly in a dedicated heating chamber (not illustrated). Liquid 15 from the reservoir 14 steadily permeates through to the surface of the wick 23, where it is heated by the heater 22 and evaporates as a vapour into the airflow path 16. As inhaled air flows along the airflow path 16 from the heater 22 towards the mouthpiece 20, the vapour mixes with it, cools and condenses into droplets, forming an aerosol that is suitable for the user to breathe in. Even with a resistance heater 22, the cartridge 2 and its components may be configured in ways very different from that illustrated. Moreover, other resistive heating solutions, such as ceramic heaters, planar die cut or printed resistive heaters or heating technologies and corresponding heater elements or systems, such as induction, may be used instead of the represented coil and wick resistive heater 22 to increase the temperature of the liquid. Aerosol generation may further be based on alternative aerolization technologies, such as nebulization, which do not necessarily require heating of the liquid 15 and that generate or inj ect suitably sized droplets of the liquid 15 directly into the airflow path to form an aerosol without heating the liquid. All of these variants are intended to fall within the scope of the invention, which is not concerned with the particular apparatus or method by which the aerosol is generated.

The heater 22 or other aerosol generator is coupled between a pair of terminals 24 on an external surface of the cartridge 2 that faces towards the device 4. Thereby, when the cartridge 2 is received in the device 4, the respective terminals 12,24 are brought into contact and complete a circuit that can deliver power from the power source 8 in the device 4 to aerosol generator 22 in the cartridge under the control of the control circuit 10.

Figure 2 schematically shows a cartridge 2 according to a first embodiment of the invention, together with the proximal end of a device 4 that is to receive the cartridge 2. As in Figure 1, the cartridge 2 comprises a reservoir 14 that delivers a supply of aerosol generating liquid 15 to a wick 23. A heater 22 vaporizes the liquid 15 from the surface of the wick 23 such that the generated vapour mixes with air in an airflow path 16 and condenses to form an aerosol. The air inlet of the airflow path 16 is not visible in Figure 2 because it lies outside the plane of the drawing. Also as in Figure 1, the heater 22 is electrically connected to a power source in the device 4 (not shown in Figure 2) via a pair of terminals 24 on the cartridge 2 that engage with a respective pair of terminals 12 on the device 4. The device terminals 12 may be in the form of springmounted “pogo pins” to ensure good contact pressure at the junction of terminals 12,24. In accordance with the invention, the engagement between the cartridge 2 and the device 4 comprises a set of projections on one of those components that are received in a complementary set of recesses on the other of those components. In this embodiment, the projections 26 are on the device 4 and the recesses 28 are in the cartridge 2. The recesses 28 in the cartridge 2 form a distinctive pattern such as a word or logo: in this case, the word “Logic”, as seen in Figure 3. The projections 26 on the device 4 form the complementary pattern, namely the inverted word “Logic”, as seen in Figure 4. In order for a cartridge 2 to operate with the device 4, it must comprise a pattern of recesses 28 that are complementary to the projections 26, therefore it must bear the same word “Logic”, which can be read by an observer viewing the distal end of the cartridge when not in use. The distinctive pattern of the recesses 28 that is required for the cartridge 2 to operate with the device preferably comprises letters or symbols that convey information about the cartridge 2. For example, the pattern may be a brand name or logo that identifies the supplier both of the device 4 and of authentic cartridges 2 for use with it, whereby a potential purchaser or any other person can immediately recognize whether a given cartridge is capable of use with the device 4. Preferably, the pattern is one that has legal protection through intellectual property rights, e.g. as a registered trade mark or a copyright work. Thereby, if an inauthentic cartridge 2 is provided with the pattern of recesses 28 required to fit to the device 4, it will infringe those rights and the rights owner can take legal action to prevent the supply of such cartridges 2.

Further in accordance with the invention, the aerosol generating system comprises a test circuit, which is coupled to the control circuit 10 in the device 4 via a pair of test terminals 30 on the device 4 that engage with a respective pair of test terminals 32 on the cartridge 2. A conductive path extends between the cartridge test terminals 32, the conductive path being formed from an alternating sequence of a first set of discrete conductive elements 34 of the cartridge 2 and a second set of discrete conductive elements 36 of the device 4. The conductive elements 36 of the second set are located on the projections 26 of the device, extending fully across the width of each projection 26 such that their edges are exposed at the sides of the projections 26. The conductive elements 36 of the second set may form the proximal end surface of each projection 26, as seen in Figure 4. It follows that the distinctive pattern of the projections 26 and recesses 28 should comprise a plurality of discrete elements (for example, the letters of a word) in order that the projections 26 can accommodate a plurality of the discrete conductive elements 36.

The conductive elements 34 of the first set extend fully between the recesses 28 of the cartridge 2, such that their edges are exposed at the sides of the recesses 28. The conductive elements 34 of the first set may take various forms but they should provide a conductive path between adjacent pairs of the recesses 28, preferably without providing a conductive path that bypasses any of the recesses 28. For example, the conductive elements 34 may be arranged to form segments of a narrow strip, as seen in dashed lines in Figure 3. The test terminals 32 of the cartridge 2 may extend across the first and last recesses 28 so as to be available for face-to-face contact with the corresponding terminals 30 of the device. In that case, conductive material will be visible in the proximal ends of the first and last recesses 28, as indicated by their solid shading in Figure 3. The cartridge preferably comprises a layer of non-conductive material, which covers the surfaces of the first set of conductive elements 34 that face towards the aerosol generating device 4.

The conductive elements 34 of the first set preferably he in a first plane and the conductive elements 36 of the second set preferably he in a second plane such that, when the projections 26 are received in the recesses 28, the two planes come into alignment and the edges of the conductive elements 34,36 of the first and second sets are brought into contact with each other, as seen in Figure 5. This forms a continuous conductive path between the cartridge test terminals 32 and completes the test circuit. The control circuit 10 can apply a voltage between the test terminals 30 and, if a current flows through the test circuit, the control circuit can determine that a suitable cartridge 2 has been correctly received in the device 4. It can then supply power through the terminals 12 to operate the heater 22 and generate an aerosol on demand from the user.

The edges of the conductive elements 34,36 of the first and second sets are not necessarily formed to be perpendicular to the plane of the conductive path, i.e. parallel to the direction in which the projections 26 are received in the recesses 28. To do so would require very tight manufacturing tolerances to ensure good conductive contact on both sides of each recess 28. One possibility, shown in Figure 6, is for the respective edges of the conductive elements 34,36 of the first and second sets to be tapered in opposite directions so that their opposing edges come together in a wedge arrangement, ensuring good contact. Another possibility is that the conductive elements 34,36 of the first and second sets are configured not to move into precisely the same plane but to be brought into face-to-face contact close to their respective edges, as shown in Figure 7.

Figures 8 to 11 show a second embodiment of aerosol generating system according to the invention, which is similar in many respects to the first embodiment. Like parts have been given the same reference numerals and will not be described again.

The second embodiment differs from the first embodiment in that it does not comprise a separate test circuit. Instead, a power circuit that delivers electric power from the power source 8 in the device 4 to the heater 22 passes through the conductive path formed by the first and second sets of conductive elements 34,36. When the projections 26 of the device 4 are received in the recesses 28 of the cartridge 2, the conductive elements 34,36 of the first and second sets are again brought into contact with each other, as seen in Figure 11. This forms a continuous conductive path between the cartridge power terminals 24 and the heater 22, which completes the power circuit. The control circuit 10 can thereby deliver current through the terminals 12 to operate the heater 22 and generate an aerosol on demand from the user.

In the illustrated embodiment, the two power terminals 12 of the device 4 are positioned adjacent to one another at the centre of the proximal end of the device 4. Thereby the conductive path formed by the coming together of the first and second sets of conductive elements 34,36 is in two parts: a first part in a first arm of the power circuit extending between one power terminal 12 and a first terminal of the heater 22; and a second part in a second arm of the power circuit extending between the other power terminal 12 and a second terminal of the heater 22. That arrangement is not essential: for example, the two power terminals 12 could be positioned to one side of the device so that only one arm of the power circuit includes the conductive path formed by the first and second sets of conductive elements 34,36.

Figures 12 to 15 show a third embodiment of aerosol generating system according to the invention, which is similar in many respects to the first embodiment. Like parts have been given the same reference numerals and will not be described again.

The third embodiment differs from the first embodiment in that the projections and the recesses are disposed the opposite way round on the cartridge 2 and the device 4. In this embodiment, the cartridge 2 carries projections 38 and the device 4 has corresponding recesses 40. The first set of conductive elements 34 is arranged on the ends of the projections 38 of the cartridge 2 and the second set of conductive elements 36 extends between the recesses 40 of the device 4. Thereby, when the cartridge 2 engages the device 2, the first and second sets of conductive elements 34,36 are brought together to form a continuous conductive path that falls within the boundaries of the device 4, rather than within the boundaries of the cartridge 2, as seen in Figure 15. Nevertheless, the continuous conductive path still comprises alternate conductive elements of the cartridge 2 and of the device 4 so that when the test circuit is completed, it indicates that a suitable cartridge 2 is correctly received in the device 4.

Figure 12 also illustrates a further, optional feature of the aerosol generating system, namely a probe 42, by which the control circuit 10 can measure the voltage at one of the intermediate conductive elements 36 of the second set. When current is flowing through the test circuit, the voltage at the intermediate conductive element 36 should be at a value intermediate between the voltages at the two test terminals 30 of the device 4. If that is not the case, then it may indicate that an inauthentic cartridge is in use, in which a bypass circuit has been installed between the two test terminals 32 of the cartridge 2. Such a bypass circuit would enable the test circuit to be completed without passing through all of the first and second conductive elements 34,36 and thereby avoiding the need for the projections 38 of the cartridge 2 to match the distinctive pattern of the recesses 40 in the device 4. It will be understood that similar voltage probes 42 could be coupled to as many of the intermediate conductive elements 36 of the second set as may be required to ensure that at least a substantial part of the pattern is replicated in the cartridge 2. Similar voltage probes 42 could be used in exactly the same way in other embodiments of the invention, including in those where the second set of conductive elements 36 form part of a power circuit rather than a test circuit.

A fourth embodiment of the invention is not illustrated but will be easily understood by reference to the second and third embodiments. As in the second embodiment, the conductive path formed by the first and second sets of conductive elements 34,36 forms part of a power circuit that delivers electric power from the power source 8 in the device 4 to the heater 22. Unlike the second embodiment but like the third embodiment, the first set of conductive elements 34 is arranged on the ends of projections 38 of the cartridge 2 and the second set of conductive elements 36 extends between recesses 40 of the device 4, whereby the continuous conductive path that falls within the boundaries of the device 4, rather than within the boundaries of the cartridge 2.

Although all the illustrated embodiments of the invention show an aerosol generator 22 - specifically, a heater - that forms part of the disposable cartridge 2, that is not essential to the invention. It may not be desirable to dispose of the aerosol generator 22 each time a cartridge 2 is replaced, especially if the generator 22 is based on more complex technology such as a jet head, therefore the aerosol generator 22 may instead form part of the reusable device 4. It remains possible for a power circuit supplying such a generator 22 to pass through a conductive path that is formed from alternative conductive elements 34,36 of the cartridge 2 and the device 4 in the same manner as the second and fourth embodiments. Alternatively, the control circuit 10 may be configured to supply power to such an aerosol generator 22 only if it determines that a test circuit has been correctly established, as in the first and third embodiments.

Claims

1. An aerosol generating system comprising: a cartridge (2) that contains a supply of aerosol generating material (15); and an aerosol generating device (4) for receiving the cartridge (2); wherein: the cartridge (2) comprises a first set of multiple discrete conductive elements (34); and the aerosol generating device (4) comprises a second set of multiple discrete conductive elements (36); the first and second sets of conductive elements (34,36) being configured such that, when the cartridge (2) is received in the aerosol generating device (4), the first set of conductive elements (34) comes into contact with the second set of conductive elements (36) to form a continuous conductive path comprising conductive elements (34,36) alternately from the first and second sets; and wherein either:

(i) the aerosol generating device (4) comprises a plurality of projections (26), the conductive elements (36) of the second set being formed on the projections (26); and the cartridge (2) comprises a plurality of recesses (28) configured to receive the projections (26) when the cartridge (2) is received in the aerosol generating device (4), the conductive elements (34) of the first set being formed to extend between the recesses (28); or

(ii) the cartridge (2) comprises a plurality of projections (38), the conductive elements (34) of the first set being formed on the projections (38); and the aerosol generating device (4) comprises a plurality of recesses (40) configured to receive the projections when the cartridge (2) is received in the aerosol generating device (4), the conductive elements (36) of the second set being formed to extend between the recesses (40).

2. An aerosol generating system according to claim 1, wherein: the aerosol generating device (4) comprises a source of electrical power (8); the cartridge (2) or the aerosol generating device (4) comprises an electrically powered aerosol generator (22); and the continuous conductive path forms part of a circuit for supplying power from the source (8) to the aerosol generator (22).

3. An aerosol generating system according to claim 2, wherein the aerosol generator (22) is an electrically powered heater in the cartridge (2).

4. An aerosol generating system according to any preceding claim, wherein: the continuous conductive path forms part of a test circuit, through which the aerosol generating device (4) can supply current to verily the correct insertion of the cartridge (2) and/or the authenticity of the cartridge (2).

5. An aerosol generating system according to claim 4, wherein the device (4) further comprises means (42) for determining whether current is flowing through at least one intermediate conductive element (36) of the second set.

6. An aerosol generating system according to any of claims 1 to 5, wherein: a plurality of the conductive elements (34) of the first set and a plurality of the conductive elements (36) of the second set lie in a common plane.

7. An aerosol generating device according to any preceding claim, wherein the conductive elements of the first set (34) he in a first plane and the conductive elements of the second set (36) he in a second plane, such that when the projections (26, 38) are received in the recesses (28), (40) the edges of the conductive elements of the first and second sets are brought into contact with each other.

8. An aerosol generating system according to claim 1 part (i), wherein the cartridge (2) further comprises a layer of non-conductive material (37), which covers surfaces of the first set of conductive elements (34) that face towards the aerosol generating device (4).

9. An aerosol generating system according to any preceding claim, wherein the recesses (28), (40) are in the shapes of letters, symbols or other patterns capable of conveying visual information.

10. An aerosol generating system according to claim 1 part (ii), wherein the aerosol generating device (4) further comprises a layer of non-conductive material (41), which covers surfaces of the second set of conductive elements (36) that face towards the cartridge (2).

11. An aerosol generating system according to any preceding claim, wherein the projections (26), (38) are in the shapes of letters, symbols or other patterns capable of conveying visual information.

12. A method of activating an aerosol generating system that comprises: a cartridge (2) containing a supply of aerosol generating material and comprising a first set of discrete conductive elements (34); and an aerosol generating device (4) comprising a second set of discrete conductive elements (36); the method comprising receiving the cartridge (2) in the aerosol generating device (4) such that the first set of conductive elements (34) comes into contact with the second set of conductive elements (36) to form a continuous conductive path comprising conductive elements (34,36) alternately from the first and second sets.

13. A method according to claim 12, wherein forming the continuous conductive path completes an electric circuit that connects an electrically powered aerosol generator (22) to a source of electrical power (8) in the aerosol generating device (4).

14. A method according to claim 12 or claim 13, wherein forming the continuous conductive path completes a test circuit, the method further comprising supplying current through the test circuit to verily the correct insertion of the cartridge (2) or the authenticity of the cartridge (2).