The present disclosure relates to a heater assembly for an aerosol-generating system, a device comprising the heater assembly, a cartridge for use with the heater assembly, an aerosolgenerating system comprising the device and the cartridge, and methods of using the heater assembly.

Aerosol-generating systems configured to generate an aerosol from an aerosol-forming substrate, such as a tobacco-containing substrate, are known in the art. Many known aerosolgenerating systems generate aerosol by the application of heat to the substrate by a heater assembly. In electrically operated aerosol-generating systems, heat is applied to the substrate when the heater assembly is supplied with power from a power supply. The generated aerosol can then be inhaled by a user of the device.

In many aerosol-generating devices, a heater element of the heater assembly is configured to heat a quantity of aerosol-forming substrate contained in a porous material such as a wick or capillary element provided adjacent to or in contact with the heater element. The porous material can transport aerosol-forming substrate in liquid form from a reservoir provided in the aerosol-generating system. In this way, aerosol-generating substrate in the vicinity of the heater element that is vaporised during use of the aerosol-generating system is continuously replenished.

Efficient heating of aerosol-forming substrate contained in the porous material is desirable to reduce the power requirements of the heater assembly. This is particularly important when the aerosol-generating system is portable and comprises a portable power supply such as a battery. Heating of the aerosol-forming substrate contained in the porous material may be efficient when there is direct contact between the porous material and the heater element. An example of such a heater assembly comprises a resistive heating element in the form of a coil of wire wrapped around a wick. At least one end of the wick extends into a reservoir of aerosol-forming substrate.

One problem with aerosol-generating systems in which a heater element is in direct contact with a porous material, such as a coil and wick type arrangement, is that, over the course of many heating cycles, the porous material can degrade. Degradation can be caused by heating of the porous material. Degradation can also be caused by chemical interactions between the aerosol-forming substrate and the porous material, mechanical stress on the porous material and particle accumulations on the surface of the porous material. Degradation of the porous material can result in less efficient heat transfer between the heating element and the porous material and less efficient transfer of liquid from the reservoir towards the heater element by the porous material. As such, the porous material has a limited useful lifetime. The useful lifetime of the porous material is typically significantly shorter than the lifetime of other components of the aerosol-generating system, for example the heater element. It is not typically possible to replace a degraded porous material without taking the system, and the heater assembly, apart. This is not something that a normal consumer is capable of doing or is inclined to do. Some aerosol-generating systems comprise a reusable aerosol-generating device and a disposable cartridge. The disposable cartridge comprises the aerosol-forming substrate and, when the aerosol-forming substrate is depleted, the cartridge can be replaced. Such cartridges can comprise the heater element and the porous material, for example the cartridge can comprise a coil and wick type arrangement. In such cases, the heater element and the porous material are disposed of along with the rest of the cartridge when the aerosol-forming substrate of the cartridge is depleted.

When the porous material is provided in a disposable cartridge, it will generally be disposed of and replaced before significant degradation as occurred and so the problem of degradation of the porous material may be avoided. However, including both the heater element and the porous material in the cartridge increases the material cost of the cartridge and the complexity of the cartridge.

More generally, high speed manufacturing of a heater element and porous material provided together and in contact with one another is difficult with at least some of the steps of the manufacturing process required to be performed by hand. In particular, high speed manufacturing of coil and wick-type arrangements is difficult. This further increases the cost of manufacturing cartridges comprising a heater element and porous material.

It would be desirable to provide a heater assembly for an aerosol-generating system in which efficient heating of an aerosol-forming substrate contained in a porous material is achieved during use. It would be desirable to provide such a heater assembly wherein degradation of components of the system, in particular the heater assembly and the porous material, is reduced compared to prior art systems, particularly compared to coil and wick type arrangements. It would further be desirable to provide such a heater assembly that is cheaper and easier to manufacture. In the context of an aerosol-generating systems comprising a disposable cartridge, it would be desirable to provide a cartridge that is cheap, simple to manufacture and that has lower a material cost.

According to a first aspect of the present disclosure there is provided a heater assembly for an aerosol-generating system. The heater assembly may comprise a heating element. The heater assembly may comprise a receiving chamber. The receiving chamber may be at least partially defined by the heating element. The receiving chamber may comprise an opening. The opening may be for receiving a wicking element of the aerosol-generating system.

The receiving chamber may have a first configuration. The receiving chamber may have a second configuration. An internal volume of the receiving chamber may be larger when the receiving chamber is in the first configuration than when the receiving chamber is in the second configuration. In the second configuration, the heating element may be in contact with the wicking element when the wicking element is received in the receiving chamber.

The receiving chamber having the first and second configuration may advantageously provide a simple and effective means by which the heater assembly can be coupled or decoupled from a wicking element received in the receiving chamber. By providing two configurations in this way, the heating element need not always be in contact with the wicking element received in the receiving chamber.

When the receiving chamber is in the second configuration, and when the wicking element is received in the receiving chamber, the contact between the heating element and the wicking element may advantageously provide for efficient heating of the wicking element by the heating element. Aerosol-forming substrate contained in the wicking element may be heated efficiently when the receiving chamber is in the second configuration. Efficient heating may advantageously be achieved because the contact between the heating element and the wicking element allows for heat conduction. Furthermore, the contact between the heating element and the wicking element may draw liquid out of the wicking element to the heating element.

When the receiving chamber is in the second configuration, and when the wicking element is received in the receiving chamber, the heater assembly may be referred to as being coupled to the wicking element.

When the receiving chamber is in the first configuration, the wicking element may be receivable and removable from the receiving chamber. The internal volume of the receiving chamber being larger when the receiving chamber is in the first configuration may advantageously mean that the heating element is not in contact with the wicking element in the first configuration of the receiving chamber such that the heater assembly is not coupled to the wicking element and the wicking element is removable.

The heater assembly may advantageously be provided as a separate component to the wicking element. The wicking element received in the receiving chamber may advantageously be replaceable separately from the heater assembly. For example, the wicking element may be replaced when it is degraded. In particular, the wicking element may advantageously be replaceable when the receiving chamber is in the first configuration without the need to disassemble the heater assembly.

Because the heater assembly can be provided as a separate component to the wicking element, the two components may advantageously be manufactured separately. Therefore, high speed manufacturing techniques may be used to manufacture the heater assembly separately from the wicking element. This might not be possible if the two components were manufactured together. For example, winding of a wick around a capillary element is difficult to achieve in a high speed automated process.

Preferably, the heater assembly may be provided as part of an aerosol-generating device. The aerosol-generating device may be configured to be used with a cartridge comprising the wicking element. The wicking element may be configured to be receivable in the receiving chamber of the heater assembly. Therefore, to use the cartridge with the aerosol-generating device, the wicking element may be insertable into the receiving chamber when the receiving chamber is in the first configuration. In use of the heater assembly to heat aerosol-forming substrate, the receiving chamber may be in the second configuration.

The aerosol-generating device may be reusable. The cartridge may be disposable. When the cartridge is to be disposed of, the receiving chamber can simply be placed in the first configuration to decouple the heater assembly from the wicking element and the cartridge be disposed of and replaced. The heater assembly may be reused. The material cost of such a cartridge is reduced compared to a cartridge that comprises both the heater assembly and the wicking element.

Providing a heater assembly which can be coupled and uncoupled from a wicking element may advantageously reduce degradation of at least one of the heating element and the wicking element received in the receiving chamber.

Degradation of the heating element and the wicking element may be caused by contact between the at least one heating element and the wicking element received in the receiving chamber of the heater assembly. A heater assembly comprising a receiving chamber having the first and second configurations may allow for reduced contact between the at least one heating element and a wicking element received in the receiving chamber compared to a heater assembly in which there is permanent contact between a heating element and a wicking element. This may reduce the degradation of the wicking element.

For example, the receiving chamber may be placed in the second configuration only during use of the aerosol-generating system when the heating element is used to heat the wicking element. Otherwise, the receiving chamber may be placed in the first configuration. In this way, the heating element may be in contact with the wicking element only during heating of the wicking element to ensure efficient heating of the wicking element is achieved. This may significantly reduce the length of time that there is contact between the heating element and the wicking element. This may advantageously extend the lifetime of the wicking element.

The heating element may be moveable or deformable to reduce the internal volume of the receiving chamber in the second configuration relative to the first configuration. The heating element may be moved or deformed in the second configuration relative the first configuration so as to contact a wicking element received in the receiving chamber.

The heater assembly may comprise an actuator. The actuator may be configured to move or deform the heating element for transition of the receiving chamber from the first configuration to the second configuration. The actuator may be configured to move or deform the heating element to reversibly configure the receiving chamber between the first configuration and the second configuration.

The receiving chamber may be configured such that the wicking element is receivable in the receiving chamber along a longitudinal direction. The longitudinal direction may define a central axis through the receiving chamber. At least a first portion of the heating element may be closer to the central axis in the second configuration than in the first direction.

At least a first component of the motion of the first portion of the heating element when the heating element is moved or deformed may be perpendicular to the longitudinal direction. The actuator may be configured such that the first component of the motion of the first portion of the heating element may be towards the central axis when the receiving chamber is reconfigured from the first configuration to the second configuration.

The heating element may comprise a second portion different to the first portion. In the second configuration of the receiving chamber, the second portion of the heating element may not contact a wicking element when the wicking element is received in the receiving chamber.

The second portion of the heating element may have a lower resistance per unit length than the first portion of the heating element. This may advantageously ensure that the second portion of the heating element is maintained at a lower temperature than the first portion of the heating element.

The second portion of the heating element may comprise or consist of material having a resistivity that is lower than the resistivity of a material of the first portion of the heating element. Providing such a material may advantageously result in the second portion of the heating element having a lower resistance per unit length than the first portion of the heating element. The second portion of the heating element may comprise a coating. The coating may comprise a material having a resistivity that is lower than the resistivity of a material of the first portion of the heating element.

The second portion of the heating element may have a cross-sectional area that is larger than the first portion. This may advantageously result in the second portion of the heating element having a lower resistance per unit length than the first portion of the heating element. In such cases, the second portion of the heating element may consist of the same material or materials as the first portion of the heating element.

In the first configuration, the receiving chamber may be configured such that the wicking element is freely removable or receivable within the receiving chamber. This may be achieved as a result of the heating element not contacting the wicking element received in the receiving chamber when the receiving chamber is in the first configuration.

In the second configuration, the receiving chamber may be configured to apply a retaining force on the wicking element when a wicking element is received in the receiving chamber. The retaining force may be at least partially applied by the heating element. The retaining force may advantageously ensure that there is contact between the heating element and the wicking element received in the receiving chamber to provide efficient heating.

The heating element may comprise or consist of a resilient material. This may be particularly advantageous when the heating element is deformable to reduce the internal volume of the receiving chamber. The heating element may be deformed in the second configuration relative to the first configuration. A heating element comprising or consisting of a resilient material may advantageously return to the shape of the first configuration when released from the second configuration.

The internal volume of the receiving chamber may be at least 5% larger, preferably at least 10% larger, preferably at least 15% larger, preferably at least 20%, even more preferably at least 30% and even more preferably at least 50% larger when the receiving chamber is in first configuration than when the receiving chamber is in the second configuration.

Preferably, the receiving chamber has an axisymmetric shape, at least in the first configuration. The axis of symmetry of the axisymmetric shape is preferably the central axis that is parallel to the longitudinal direction. Preferably, the receiving chamber is cylindrical in at least the first configuration.

The receiving chamber may have an axis symmetric shape in the second configuration. The axis of symmetry of the axisymmetric shape is preferably the central axis that is parallel to the longitudinal direction. Preferably, the receiving chamber is cylindrical the second configuration.

At least in the first configuration, the receiving chamber may have a width of between 1 millimeter and 12 millimeters, preferably between 3 millimeters and 7 millimeters. If the receiving chamber is cylindrical, the values for the width correspond to values for the diameter of the cylindrical chamber.

A cross-sectional dimension of the receiving chamber may be larger when the when the receiving chamber is in first configuration than when the receiving chamber is in the second configuration. The cross-sectional dimension may be a cross-sectional area or a width of a crosssection of the receiving chamber. When the receiving chamber is cylindrical, the cross-sectional dimension may be the diameter of the receiving chamber.

The cross-sectional dimension of the receiving chamber may be at least 5% larger, preferably at least 10% larger, preferably at least 15% larger, preferably at least 20%, even more preferably at least 30% and even more preferably at least 50% larger when the receiving chamber is in first configuration than when the receiving chamber is in the second configuration.

The cross-sectional dimension may be a dimension of a cross-section of the receiving chamber that is perpendicular to the longitudinal direction.

The heating element may comprise a coil. The coil may be wound around the central axis. The receiving chamber may be at least partially defined by the coil.

The coil may have an electrical resistance of between 0.4 ohms to 4 ohms.

The coil may be formed by a coil of wire. The wire may have a diameter of between 0.1 millimeters and 1 millimeter, preferably between 0.2 millimeters and 0.5 millimeters. The length of the wire may be between 10 millimeters and 150 millimeter, preferably between 20 millimeter and 50 millimeter. The coil may be deformable to reduce the internal volume of the receiving chamber in the second configuration relative to the first configuration. The heater assembly may comprise an actuator configured to deform the coil for transition of the receiving chamber from the first configuration to the second configuration.

In the second configuration of the receiving chamber, at least a first portion of the coil may contact the wicking element when the wicking element is received in the receiving chamber.

The heating element may comprise a first end and a second end. The coil may be defined between the first end and the second end.

The first and second ends of the heating element may further comprise or form one or more contact portions. The first and seconds ends of the heating element may not be in the shape of a coil.

The first and second contact portions may advantageously be mechanically connected to, or connectable to, the actuation means. The actuation means may be configured to deform the heating element by manipulating the first and second contact portions.

Preferably, the first and second contact portions are electrical contact portions. The first heater element may advantageously be connectable to a power supply via the first and second electrical contact portions. The power supply may be external to the heater assembly. For example, an aerosol-generating device that comprises the heater assembly may also comprise the power supply.

The first end of the heating element may be moveable relative to the second end of the heating element to reduce the internal volume of the receiving chamber in the second configuration relative to the first configuration. Preferably, the first end of the heating element may be rotatable relative to the second end of the heating element to reduce the internal volume of the receiving chamber in the second configuration relative to the first configuration. The first end of the heating element may be rotatable about the central axis relative to the second end of the heating element.

The receiving chamber may be at least partially defined by the coil of the heating element. Rotation of the first end relative to the second end of the heater element may deform the coil.

The coil may be a helical coil. The helical coil may be axially symmetric about a helical axis. The helical axis may be parallel to the central axis. The helical axis may, preferably, correspond to the central axis. The helical coil may have a circular cross-section.

The diameter of the coil may be larger when the receiving chamber is in the first configuration than when the receiving chamber is in the second configuration. The cross-section of the coil may be a cross-section that is perpendicular to the helical axis of the coil.

The pitch of the coil may be larger when the receiving chamber is in the first configuration than when the coil is in the second configuration.

As used herein, the “pitch” of the helical coil is the length of one complete helix turn, measured along the helical axis of the helical coil. The total number of turns of the coil may be smaller when the receiving chamber is in the first configuration than when the receiving chamber is in the second configuration. The total number of turns of the coil may increase by a non-integer number of turns between the first and second configurations of the receiving chamber. The total number of turns may increase by a fraction of one turn between the first and second configurations of the receiving chamber.

The number of turns per unit length of the coil may be smaller when the coil is in the first configuration than when the coil is in the second configuration.

The length of the coil may be substantially the same when the coil is in the first configuration as when the coil is in the second configuration. In other words, the distance between the first end and the second end of the coil along the central axis may be substantially the same when the receiving chamber is in both the first configuration and the second configuration.

The actuator of the heater assembly may be configured to move or rotate the first end of the coil relative to the second end of the coil for transition of the receiving chamber between the first configuration to the second configuration. Preferably, the actuator may be configured to move or rotate the first and second contact portions of the heating element which, in turn, causes movement or rotation of the first and second ends of the coil which are connected to the first and second contact portions respectively.

The helical coil may be a left-handed helical coil or a right-handed helical coil. As used herein, whether the helical coil is “left-handed” or “right-handed” is defined along the length of the central axis in a direction from the first end to the second end of the heating element.

When the helical coil is left-handed, the actuator may be configured to rotate the first end of the coil relative to the second end of the coil in a clockwise direction for transition of the receiving chamber from the first configuration to the second configuration. The actuator may additionally or alternatively be configured to rotate the second end of the coil relative to the first end of the coil in a counter-clockwise direction for transition of the receiving chamber from the first configuration to the second configuration.

When the helical coil is right-handed, the actuator may be configured to rotate the first end of the coil relative to the second end of the coil in a counter-clockwise direction for transition of the receiving chamber from the first configuration to the second configuration. The actuator may additionally or alternatively be configured to rotate the second end of the coil relative to the first end of the coil in a clockwise direction for transition of the receiving chamber from the first configuration to the second configuration. This may result in an increase in the total number of turns of the coil (although the increase may be less than one full turn).

The heating element may comprise spaces configured to allow air to pass through the heating element, at least when the receiving chamber is in the second configuration. The spaces may advantageously allow vaporized aerosol-forming substrate to escape the wicking element received in the receiving chamber during use of the heater assembly. When the heating element is a helical coil, the spaces may be defined between sequential turns of the helical coil, at least when the receiving chamber is in the second configuration.

The heater assembly may comprise a heating element housing. The heating element may be at least partially contained within the heating element housing. At least a portion of the heating element may be surrounded by the heating element housing. The heating element housing may form a hollow body containing at least a portion the heating element.

The heating element housing may comprise one or more engagement members. The one or more engagement members may be configured to engage corresponding engagement members of a cartridge comprising a wicking element to be received in the receiving chamber. The one or more engagement members may be configured such that the heating element housing is configured to engage the cartridge. The one or more engagement members may be configured such that the heating element housing is configured to engage the cartridge be rotating the heating element housing relative to the cartridge.

The one or more engagement members may comprise one or more protrusions configured to be received in one or more corresponding slots of the cartridge.

Alternatively or additionally, the one or more engagement members may comprise one or more slots configured to receive one or more corresponding protrusions of the cartridge.

The one or more engagement members may be configured such that heating element housing is engaged to the cartridge when the receiving chamber is in the second configuration. The one or more engagement members may be configured to prevent disengagement of the heating element housing from the cartridge when the receiving chamber is in the second configuration. This may prevent damage to the heating element or the wicking element.

The actuator may comprise a user interface element and an actuation mechanism. The actuation mechanism may be configured to actuate the receiving chamber between the first configuration and the second configuration in response to an input on the user interface element.

The actuation mechanism may be configured to convert a motion of the user interface during an input to move or deform the heating element. Preferably, the user interface may be moveable between a first position and a second position. The actuation mechanism may be configured such that movement of the user interface from the first position to the second position reconfigures the receiving chamber from the first configuration to the second configuration. The actuation mechanism may further be configured such that the movement of the user interface from the second position to the first position reconfigures chamber from the second configuration to the first configuration.

The actuation mechanism may comprise the heating element housing. The heating element housing may comprise a first portion and a second portion. At least the first portion of the heating element housing may form the user interface element. The first portion of the heating element housing may be moveable relative to the second portion. Preferably, the first portion of the heating element housing may be rotatable relative to the second portion. Even more preferably, the first portion of the heating element housing may be rotatable relative to the second portion about the central axis. Advantageously, rotation of the first portion of the heating element housing relative to the second portion of the heating element housing may move or deform the heating element for transition of the receiving chamber between the first and second configurations.

Alternatively, the actuator may be electrically operated and controlled by control circuitry. The control circuitry may be configured to control the actuator for transition of the receiving chamber from the first position to the second position, or from the second position to the first position, as required. For example, at the start of a usage session of the device, a user may activate the system. Activation may comprise a user pressuring a button or other user interface element of the device. Activation may alternatively comprise a user drawing air through a mouthpiece of the system which may be detected by a puff detector arrangement. The control circuitry may be configured for transition of the receiving chamber from the first position to the second position on activation of the device. The control circuitry may also be configured to supply power to the heater assembly.

The control circuitry may be configured for transition of the receiving chamber from the second position to the first position at the end of a usage session or when the device is otherwise deactivated.

As above, the heating element may comprise a coil wound around a central axis and further comprise a first end and a second end with the coil defined between the first end and the second end. The first end of the heating element may be engaged to the first portion of the heating element housing. Preferably, the first end of the heating element may be permanently fixed to the first portion of the heating element housing. A second end of the heating element may be engaged to the second portion of the heating element housing. Preferably, the second end of the heating element may be permanently fixed to the second portion of the heating element housing.

Engaging or permanently fixing the heating element at the first and second ends to the heating element housing may advantageously constrain the coil so that rotation of the first portion of the heating element housing relative to the second portion deforms the heating element to reduce the internal volume. This may be because rotational motion of the first portion of the heating element housing relative to the second portion of the heating element housing may be transferred to heating element so that the first end of the heating element is rotated relative to the second end of the heating element for transition of the receiving chamber between the first configuration to the second configuration. Furthermore, the separation of the first end of the heating element relative to the second end of the heating element along the central axis may be maintained as substantially constant in both the first and second configurations. As such, the length of the coil may be maintained substantially constant in the both first and second configurations. Thus, the rotation of the two ends of the heating element relative to one another may change the diameter, pitch and number of turns per unit length of a helical coil. Whether the rotation of the heating element housing reconfigures the receiving chamber between the first configuration and second configuration will depend on whether coil is left or right handed and the direction that the first portion of the heating element housing is rotated relative to first portion of the heating element housing.

Preferably, the coil may be not be engaged or fixed to the heating element housing other than at the first end and at the second end. In this way, the coil may advantageously be free to deform between the first and second ends.

In the first configuration, the coil of the heating element may be in contact with the heating element housing along the length of the coil.

In the second configuration, the coil of the heating element may not be in contact with the heating element housing. In the second configuration, the heating element may not be in contact with the heating element housing other than at the first and second ends.

At least when the receiving chamber is in the second configuration, an airflow path may be defined between the heating element housing and the heating element. The receiving chamber may be at least partially defined by a first side of the heating element. The airflow path may be at least partially defined on a second side of the heating element, opposite the first side, at least when the receiving chamber is in the second configuration.

At least when the receiving chamber is in the second configuration, an aerosol-generating chamber may be defined between the heating element housing and the heating element. Therefore the heater assembly may comprise a heating chamber, the heating chamber comprising the receiving chamber and the aerosol-generating chamber.

When the heating element comprises a coil, the receiving chamber may be defined on be an inner surface of the coil. So, if the coil is a helical coil with a cylindrical cross-section, the receiving chamber may be cylindrical also. The airflow path may be at least partially defined on an outer surface of the coil, opposite the inner surface of the coil, at least when the receiving chamber is in the second configuration.

The heater assembly may comprise an actuator. The actuator may be configured to move at least the heating element for transition of the receiving chamber from the first configuration to the second configuration.

The heater assembly has been described as comprising a heating element. As such, the heater assembly may comprise further heating elements. For example, the heater assembly may comprise a first and a second heating element. The heater assembly may comprise a third heating element. The heater assembly may comprise a fourth heating element.

Each of the heating elements may have features corresponding to the features of the heating element. For example, each of the heating elements may be in contact with the wicking element when the wicking element is received in the receiving chamber and the receiving chamber is in the second configuration. Each of the heating elements may be moveable or deformable to reduce the internal volume of the receiving chamber in the second configuration relative to the first configuration. An actuator of the heater assembly may be configured to move or deform each of the heating elements for transition of the receiving chamber from the first configuration to the second configuration.

When the heating element comprises a coil, one or more of the further heating elements may also comprise a coil having a corresponding features to the coil of the heating element. For example, the one or more further heating element may each comprise a coil, a first end and a second end. Each coil may be a helical coil. In other words, the heater assembly may comprise a plurality of coils.

The helical axis of each of the plurality of coils may be parallel to one another. The helical axis of each of the plurality of coils may be the central axis.

One or more of the plurality of coils may overlap with another.

The plurality of coils may be distributed along the central axis. The plurality of coils may be spaced apart along the length of the central axis.

When the heating element comprises a coil between a first end a second end, the actuator may be configured to move or rotate the first end of the coil relative to the second end of the coil for transition of the receiving chamber between the first configuration or second configuration to a third configuration. Preferably, the actuator may be configured to move or rotate the first and second contact portions of the heating element.

When the helical coil is left-handed, the actuator may be configured to rotate the first end of the heating element relative to the second end of the heating element in a clockwise direction for transition of the receiving chamber from the first or second configuration to the third configuration. The actuator may additionally or alternatively be configured to rotate the second end of the heating element relative to the first end of the coil in a counter-clockwise direction for transition of the receiving chamber from the first or second configuration to the third configuration.

When the helical coil is right-handed, the actuator may be configured to rotate the first end of the heating element relative to the second end of the heating element in a counterclockwise direction for transition of the receiving chamber from the first or second configuration to the third configuration. The actuator may additionally or alternatively be configured to rotate the second end of the heating element relative to the first end of the heating element in a clockwise direction for transition of the receiving chamber from the first or second configuration to the third configuration.

As above, the actuator may be electrically operated and controlled by control circuitry. The control circuitry may be configured to actuate the receiving chamber from the first configuration to the third configuration before actuating the receiving chamber to the second configuration. This may force aerosol-forming substrate out of the wicking element, as described above. The control circuitry may be configured to actuated the receiving chamber from the first configuration to the third configuration before supplying power to the heater assembly to heat the aerosol-forming substrate or at the start of a usage session. As above, this may increase the amount of aerosol that is generated at the start of the puff. The control circuitry is configured to actuate the receiving chamber from the second configuration to the third configuration at the end of a usage session. As above, this may advantageously reduce or minimize cross contamination.

The control circuitry may be configured to actuate the receiving chamber from the third configuration to the second configuration after actuating the receiving chamber from the first configuration to the third configuration. This may be particularly advantageous at the start of a usage session.

The control circuitry may be configured to then actuate the receiving chamber from the second configuration to the third configuration and back to the second configuration. This may advantageously pump the wicking element, as described above. The control circuitry may be configured to repeatedly actuate the receiving chamber from the second configuration to the third configuration and back to the second configuration a plurality of times.

The control circuitry may be configured to actuate the receiving chamber from the third configuration to the first configuration after actuating the receiving chamber from the second configuration to the third configuration. This may be particularly advantageous at the end of a usage session.

In a second aspect of the present disclosure there is provided an aerosol-generating device. The aerosol-generating device may be an electrically heated aerosol-generating device. The aerosol-generating device may comprise the heater assembly of the first aspect.

As used herein, the term “aerosol-generating device” is used to describe a device that interacts with an aerosol-forming substrate of an aerosol-generating article to generate an aerosol. Preferably, the aerosol-generating article is a cartridge. Even more preferably, the aerosol-generating article is a cartridge according to the third aspect, below.

As used herein, the term “aerosol-forming substrate” denotes a substrate consisting of or comprising an aerosol-forming material that is capable of releasing volatile compounds upon heating to generate an aerosol.

As used herein, the term “aerosol-forming material” denotes a material that is capable of releasing volatile compounds upon heating to generate an aerosol. An aerosol-forming substrate may comprise or consist of an aerosol-forming material.

The device may comprise a device housing. The device housing may form the heating element housing.

The aerosol-generating device may comprise a power supply. The power supply may be contained in the device housing. The power supply may be electrically connectable to the heating element.

When the heating element comprises a coil wound around a central axis and a first end and a second end, the power supply may be connected to or connectable to electrical contact portions formed by the first end and second end.

The power supply may be a DC power supply having a DC supply voltage in the range of about 2.5 Volts to about 4.5 Volts and a DC supply current in the range of about 1 Amp to about 10 Amps (corresponding to a DC power supply in the range of about 2.5 Watts to about 45 Watts). The power supply may be a battery, such as a rechargeable lithium ion battery. Alternatively, the power supply may be another form of charge storage device such as a capacitor. The power supply may be rechargeable. The power supply may have a capacity that allows for the storage of enough energy for one or more uses of the aerosol-generating device. For example, the power supply may have sufficient capacity to allow for the continuous generation of aerosol for a period of around six minutes, corresponding to the typical time taken to smoke a conventional cigarette, or for a period that is a multiple of six minutes. In another example, the power supply may have sufficient capacity to allow for a predetermined number of puffs or discrete activations.

The heating element may be a resistive heating element. The heating element may comprise an electrically resistive material. Suitable electrically resistive materials include but are not limited to: semiconductors such as doped ceramics, electrically “conductive” ceramics (such as, for example, molybdenum disilicide), carbon, graphite, metals, metal alloys and composition materials made of ceramic material and a metallic material. Such composite materials may comprise doped and undoped ceramics.

The power supply may be configured to supply current to the resistive heating element in use.

An aerosol-generating device comprising a resistive heating element may be described as a resistively heated aerosol-generating device.

Alternatively, the aerosol-generating device may be an inductively heated aerosolgenerating device. An inductively heated aerosol-generating device may comprise an inductor coil. The inductor coil may be connected to or connectable to the power supply.

When the aerosol-generating device comprises an inductor coil, the aerosol-generating device may be configured to supply an alternating current to the inductor coil. The alternating current may have any suitable frequency. The alternating current may preferably be a high frequency alternating current. The alternating current may have a frequency between 100 kilohertz (kHz) and 30 megahertz (MHz). In use, the alternating current supplied to the inductor coil may generate an changing magnetic field.

When the power supply is configured to supply an alternating current the aerosolgenerating device may advantageously comprise a direct current to alternating current (DC/AC) inverter for converting a DC current supplied by the DC power supply to an alternating current. The DC/AC converter may comprise a Class-D or Class-E power amplifier. The power supply may be configured to provide the alternating current.

The inductor coil may surround or be adjacent to the heating element of the heater assembly. In such cases, the heating element may be a susceptor element.

As used herein, a “susceptor” or “susceptor element” means a conductive element that heats up when subjected to the changing magnetic field generated by the inductor coil. This may be the result of eddy currents induced in the susceptor element or hysteresis losses (or both eddy currents induced in the susceptor element and hysteresis losses). Possible materials for the susceptor include graphite, molybdenum, silicon carbide, stainless steels, niobium, aluminium and virtually any other conductive elements.

The aerosol-generating device may comprise a control circuitry. The control circuitry may be a microprocessor, which may be a programmable microprocessor, a microcontroller, or an application specific integrated chip (ASIC) or other electronic control circuitry. The control circuitry may be configured to regulate the supply of power from the power supply to the heater assembly. The controller of the device may be configured to control the actuator when the actuator is electrically operated.

In a third aspect of the present disclosure there is provided a cartridge. The cartridge may be for use with a heater assembly as defined in the first aspect. Preferably, the cartridge may be for use with an aerosol-generating device as defined in the second aspect. The cartridge may comprise a cartridge housing. The cartridge housing may define a reservoir. The reservoir may comprise an aerosol-forming substrate. The aerosol-generating substrate may be in condensed form at room temperature. Preferably the aerosol-generating substrate is a liquid at room temperature. The cartridge may further comprise a wicking element. The wicking element may be in fluidic communication with the aerosol-forming substrate.

A first portion of the wicking element may extend from the reservoir. The first portion of the wicking element may be configured to be received in the receiving chamber of the heater assembly of the first aspect. The wicking element may be configured to be received in the receiving chamber of the heater assembly such that the receiving chamber, in the second configuration, contacts the wicking element.

The wicking element of the cartridge being configured to be received in the receiving chamber of the heater assembly of the first aspect advantageously provides a simple and effective means by which the heater assembly can be coupled or decoupled from the wicking element. When the wicking element is received in the receiving chamber of the heater assembly and the receiving chamber is in the second configuration, the contact between the heating element and the wicking element may advantageously provide for efficient heating of the wicking element by the heating element.

In the first configuration of the heater assembly, the wicking element may be receivable and removable from the receiving chamber.

At least the first portion of the wicking element may have a shape that corresponds to the shape of the receiving chamber of the heater assembly in which the wicking element is configured to be received. Preferably, at least the first portion of the wicking element has an axis symmetric shape. Preferably, at least the first portion of the wicking element is cylindrical.

At least the portion of the wicking element that is received in the receiving chamber may have a length between 3 millimetres and 15 millimetres, preferably between 5 and 10 millimetres. The wicking element may have a width of between 1 millimeter and 12 millimeters, preferably between 3 millimeters and 7 millimeters. If the wicking element is cylindrical, the values for the width correspond to values for the diameter of the cylindrical wicking element.

The first portion of the wicking element may comprise a first end. The first end may be exposed to the surrounding air. A second end of the wicking element may be in fluidic communication with aerosol-forming substrate in the reservoir. The second end of the wicking element may be opposite to the first end.

In use, and when the wicking element is received in the receiving chamber of the heater assembly, the first portion of the wicking element may be heated by the heating element. Aerosolforming substrate contained in the first end of the wicking element may be vaporised. The vaporised aerosol-forming substrate in the wicking element may advantageously be continuously replenished by the liquid contained in the reservoir. The liquid may be transported by the wicking element from the second end to the first end.

A cartridge according to the disclosure may advantageously be simple to manufacture. Preferably, the cartridge may not comprise a heater assembly. In particular, the cartridge may not comprise the features of the heater assembly defined in the first aspect. As such, the material cost and complexity of cartridges according to the disclosure may be lower than for cartridges of the prior art that comprise both a heating element and a porous material, for example cartridges comprising coil and wick type arrangements.

The cartridge housing may comprise a wall extending from the reservoir and surrounding the wicking element. The wall may extend from the reservoir at least as far as the first portion of the wicking element. The wall may be a downwardly depending wall. The wall may advantageously protect the wicking element.

The wall of the cartridge housing may define a cavity with an open end. The first portion of the wicking element may be positioned within the cavity.

The wall may be configured such that at least a portion of the heater assembly is receivable in the cavity defined by the wall. As such, when the wicking element is received in the receiving chamber of the heater assembly, a portion of the heater assembly is received in the cavity defined by the wall of the cartridge. Preferably, at least a portion of the heating element is received in the cavity. If the heater assembly comprises a heating element housing, at least a portion of the heating element housing may be received in the cavity.

The cavity defined by the wall may be closed by a deformable membrane. The first portion of the wicking element may be enclosed between the wall and the membrane. The combination of the membrane and the wall may advantageously protect the wicking element prior to the cartridge being used with a heater assembly or aerosol-generating device.

The combination of the membrane and the wall may advantageously seal the wicking element. This may prevent exposure of the wicking element, and the aerosol-forming substrate contained in the wicking element, to air. Sealing the wicking element may also prevent leakage of aerosol-forming substrate during transit of the cartridge.

The membrane may be a non-fluid permeable membrane.

The membrane may comprise or consist of a flexible material. The membrane may comprise or consist of a deformable material.

The membrane may comprise a plurality of elements that together close the end of the wall of the cartridge housing. This may advantageously protect the wicking element. Each of the plurality of elements may be deformable. The membrane may be configured such that, as the wicking element is received in the receiving chamber, the heater assembly deforms the plurality of elements to reveal the wicking element.

The membrane may be provided initially as a single breakable element. The single breakable element may comprise lines of weakness. The membrane may advantageously be breakable along the lines of weakness. The plurality of elements of the membrane may be defined by the lines of weakness. Such a membrane may be preferable when the purpose of the membrane is to seal the wicking element. The membrane may be configured such that, as the wicking element is received in the receiving chamber, the heater assembly breaks the membrane to reveal the wicking element.

The wicking element may have a fibrous or spongy structure. The wicking element preferably comprises a bundle of capillaries. For example, the wicking element may comprise a plurality of fibres or threads or other fine bore tubes. The fibres or threads may be generally aligned to convey liquid to the heater. Alternatively, the wicking element may comprise spongelike or foam-like material. The structure of the wicking element may form a plurality of small bores or tubes, through which the liquid can be transported by capillary action. The wicking element may comprise any suitable material or combination of materials. Examples of suitable materials are a sponge or foam material, ceramic- or graphite-based materials in the form of fibres or sintered powders, foamed metal or plastics material, a fibrous material, for example made of spun or extruded fibres, such as cellulose acetate, polyester, or bonded polyolefin, polyethylene, terylene or polypropylene fibres, nylon fibres or ceramic. The wicking element may have any suitable capillarity and porosity so as to be used with different liquid physical properties. The liquid has physical properties, including but not limited to viscosity, surface tension, density, thermal conductivity, boiling point and vapour pressure, which allow the liquid to be transported through the capillary device by capillary action.

The wicking element may be a ceramic wick. The ceramic wick may comprise, or preferably consist of, a ceramic material. Preferably, when the wicking element is a ceramic wick, the wicking element may comprise a porous ceramic. The porous ceramic wick may comprise an open-porous ceramic. A ceramic wick may be rigid. A ceramic wick may not deform when the receiving chamber is in the second configuration. Preferably, the wicking element may comprise or consist of a resilient material. Such a wicking element may advantageously return to its original shape after being compressed.

An airflow path may be defined through the cartridge. The airflow path may extend through the cartridge from an air inlet to an air outlet.

The cartridge may comprise a mouthpiece portion. The mouthpiece portion may be provided on an end of the cartridge that is opposite to the first portion of the wicking element. The air outlet may be formed in the mouthpiece portion of the cartridge. As such, a user of the cartridge may draw air through the airflow path by inhaling through the mouthpiece portion.

The air inlet may be annular in shape. The annular air inlet may surround the wicking portion.

At least a portion of the airflow path may extend through the reservoir portion. At least a portion of the airflow path extending through the reservoir portion may be annular in shape. The portion of the airflow path extending through the reservoir portion may be defined by the cartridge housing.

At least a portion of the airflow path may be defined by an outer surface of the wicking element. As such, vapour generated by heating the aerosol-forming substrate contained in the wick may be released directly into air flowing through the airflow path.

The aerosol-forming substrate contained in the cartridge is a substrate capable of releasing volatile compounds that can form an aerosol. The volatile compounds may be released by heating the aerosol-forming substrate. The aerosol-forming substrate may be solid or liquid or comprise both solid and liquid components. The aerosol-forming substrate may be a gel. The gel may be a solid at room temperature. “Solid” in this context means that the gel has a stable size and shape and does not flow. Room temperature in this context means 25 degrees Celsius.

Preferably, the second aerosol-forming substrate is a liquid.

The aerosol-forming substrate may comprise plant-based material. The aerosol-forming substrate may comprise tobacco. The aerosol-forming substrate may comprise a tobaccocontaining material containing volatile tobacco flavour compounds, which are released from the aerosol-forming substrate upon heating. Preferably, the aerosol-forming substrate may alternatively comprise a non-tobacco-containing material.

The aerosol-forming substrate may comprise at least one aerosol-former. An aerosolformer is any suitable known compound or mixture of compounds that, in use, facilitates formation of a dense and stable aerosol and that is substantially resistant to thermal degradation at the temperature of operation of the system. Suitable aerosol-formers are well known in the art and include, but are not limited to: polyhydric alcohols, such as triethylene glycol, 1 ,3-butanediol and glycerine; esters of polyhydric alcohols, such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate. Preferred aerosol formers are polyhydric alcohols or mixtures thereof, such as triethylene glycol, 1 ,3-butanediol and, most preferred, glycerine. The aerosol-forming substrate may comprise other additives and ingredients, such as flavourants.

The aerosol-forming substrate may be adsorbed, coated, impregnated or otherwise loaded onto a carrier or support. The carrier or support may be separate to the wicking element.

The aerosol-forming substrate may be contained in the reservoir. The reservoir may have any suitable shape and size depending on the requirements of the aerosol-generating system.

The cartridge may comprise one or more engagement members that are configured to engage the cartridge to a housing of the heater assembly.

The one or more engagement members may be adjacent to the wicking element.

The one or more engagement members may be configured such that the cartridge is configured to engage the heater assembly by rotating the cartridge relative to the heater assembly. When the heater assembly comprises a heating element housing, the engagement members may be configured to engage the heating element housing. When the heating element housing comprises a first portion that is rotatable relative to a second portion, the engagement members may be configured to engage the heater assembly by rotating the cartridge relative to the heater assembly about the same axis of rotation as the rotatable first and second portions. This may advantageously mean that the cartridge may be engaged to the heater assembly and the receiving chamber may be reconfigured from the first position to the second position in a single motion.

The one or more engagement members may comprise one or more protrusions configured to be received in one or more corresponding slots of the heating element housing.

Alternatively or additionally, the one or more engagement members may comprise one or more slots configured to receive one or more corresponding protrusions of the heating element housing.

The one or more engagement members may be configured such that heating element housing is engaged to the cartridge when the receiving chamber is in the second configuration. The one or more engagement members may be configured to prevent disengagement of the heating element housing from the cartridge when the receiving chamber is in the second configuration. This may prevent damage to the heating element or the wicking element.

In a fourth aspect of the disclosure there is provided an aerosol-generating system. The aerosol-generating system may comprise the aerosol-generating device. The aerosol-generating device may be an aerosol-generating device as defined in the second aspect. The aerosolgenerating system may comprise a cartridge. The cartridge may comprise a wicking element configured to be received or receivable in the receiving chamber of the heater assembly.

The cartridge may be a cartridge as defined in the third aspect.

At least a portion of the wicking element may be received or receivable in the receiving chamber of the heater assembly. In the second configuration of the receiving chamber, the heating element may be in contact with the wicking element when the wicking element is received in the receiving chamber.

The heating element may be configured to deform the wicking element when the receiving chamber is in the second configuration.

The cartridge may be removably connected from the aerosol-generating device.

The heater assembly may comprise a heating element housing. The cartridge may be couplable to the heating element housing.

In a fifth aspect of the disclosure, there is a provided a method of using the heater assembly as defined in the first aspect. The method may comprise receiving a wicking element in the receiving chamber of the heater assembly while the receiving chamber is in first configuration. The method may further comprise transitioning the receiving chamber from the first configuration to the second configuration such that the heating element is in contact with the wicking element. The wicking element may be a wicking element of a cartridge as defined in the third aspect. The heater assembly may be a heater assembly that is part of an aerosol-generating device as defined in the second aspect.

The step of transitioning the receiving chamber may comprise moving or deforming the heating element.

The heating element may comprise a first end, a second end and a coil wound around a central axis. The step of transitioning the receiving chamber may comprise rotating the first end relative to the second.

The method may further comprise transitioning the receiving chamber from the second configuration to the first configuration. The method may further comprise removing the wicking element received in the receiving chamber while the receiving chamber is in the first configuration.

In a sixth aspect of the disclosure there is provided a method of using the heater assembly as defined in the first aspect. The method may comprise transitioning the receiving chamber from the second configuration to the first configuration. The method may further comprise removing a wicking element received in the receiving chamber while the receiving chamber is in the first configuration.

The step of transitioning the receiving chamber may comprise moving or deforming the heating element.

The heating element may comprise a first end, a second end and a coil wound around a central axis. The step of transitioning the receiving chamber may comprise rotating the first end relative to the second.

In a seventh aspect of the disclosure there is provided a method of controlling an aerosolgenerating device as defined in the second aspect. The aerosol-generating device may comprise an electrically operated actuator controlled by control circuitry. The method of controlling the aerosol-generating device may comprise the step configuring the receiving chamber in the second configuration. The method may comprise supplying power to the heating element to generate an aerosol from an aerosol-forming substrate. The step of configuring the receiving chamber in the second configuration may be performed before the step of supplying power to the heating element.

The step of configuring the receiving chamber in the second configuration may comprise transitioning the receiving chamber from the first configuration to the second configuration.

The method may comprise re-configuring the receiving chamber from the second configuration to the first configuration after the step of supplying power to the heating element.

In an eight aspect of the disclosure there is provided a cartridge. The cartridge may be for use with an aerosol-generating device. The cartridge may comprise a heater assembly as defined in the first aspect. That is, the cartridge may comprise a wicking element in fluidic communication with the aerosol-forming substrate. The cartridge may comprise a heating element. The cartridge may comprise a receiving chamber at least partially defined by the heating element. The wicking element may be received in the receiving chamber; wherein the receiving chamber has a first configuration and a second configuration. An internal volume of the receiving chamber may be larger when the receiving chamber is in the first configuration than when the receiving chamber is in the second configuration. In the second configuration, the heating element may in contact with the wicking element.

The cartridge may comprise a cartridge housing. The cartridge housing may define a reservoir comprising an aerosol-forming substrate in condensed form. The cartridge may comprise a wicking element in fluidic communication with the aerosol-forming substrate. A first portion of the wicking element may extend from the reservoir. The first portion of the wicking element may be configured to be received in the receiving chamber of the heater assembly such that the receiving chamber, in the second configuration, contacts the wicking element. Providing a cartridge comprising both the wicking element and the heater assembly comprising the receiving chamber means that the heater assembly and the wicking element may be coupled to one another in the second configuration but not the first configuration. This may reduce degradation of the wicking element or the heater assembly compared to if there was constant contact between the wicking element and heating element. In the first configuration, it may be straightforward to replace the wicking element of the cartridge.

Features described in relation to one aspect may be applied to other aspects of the disclosure. In particular advantageous or optional features described in relation to the first aspect of the disclosure may be applied to the second, third, fourth, and eighth aspects of the invention. For example, the advantageous or options features of the puff sensor assembly and, in particular, the heat transfer element of the puff sensor assembly described in relation to the aerosol-generating device of the first aspect can be applied to the aerosol-generating device of the fourth aspect. The invention is defined in the claims. However, below there is provided a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

EX1. A heater assembly for an aerosol-generating system, the heater assembly comprising: a heating element; and a receiving chamber at least partially defined by the heating element, the receiving chamber comprising an opening for receiving a wicking element of the aerosol-generating system; wherein the receiving chamber has a first configuration and a second configuration, an internal volume of the receiving chamber being larger when the receiving chamber is in the first configuration than when the receiving chamber is in the second configuration; and wherein, in the second configuration, the heating element is in contact with the wicking element when the wicking element is received in the receiving chamber.

EX2. A heater assembly according to example EX1 , wherein the heating element is moveable or deformable to reduce the internal volume of the receiving chamber in the second configuration relative to the first configuration.

EX3. A heater assembly according to example EX1 or EX2, wherein the heater assembly further comprises an actuator configured to move or deform the heating element for transition of the receiving chamber from the first configuration to the second configuration.

EX4. A heater assembly according to any one of the preceding examples, wherein, in the first configuration, the receiving chamber is configured such that the wicking element is freely removable or receivable within the receiving chamber.

EX5. A heater assembly according to any one of the preceding examples, wherein, in the second configuration, the receiving chamber is configured to apply a retaining force on the wicking element when a wicking element is received in the receiving chamber.

EX6. A heater assembly according to any one of the preceding examples, wherein the heating element comprises or consists of a resilient material.

EX7. A heater assembly according to any one of the preceding examples, wherein the internal volume of the receiving chamber is at least 2% larger, preferably at least 3% larger, 4% larger, or 5% larger, when the receiving chamber is in first configuration than when the receiving chamber is in the second configuration.

EX8. A heater assembly according to any one of the preceding examples, wherein the receiving chamber is cylindrical in at least the first configuration.

EX9. A heater assembly according to any one of the preceding examples, wherein a cross-sectional dimension of the receiving chamber is larger when the receiving chamber is in first configuration than when the receiving chamber is in the second configuration. EX10. A heater assembly according to example EX9, wherein the cross-sectional dimension is a cross-sectional area.

EX11 . A heater assembly according to example EX9, wherein the receiving chamber is cylindrical and wherein the cross-sectional dimension is the diameter of the receiving chamber.

EX12. A heater assembly according to any one of examples EX9 to EX11 , wherein the wicking element is receivable in the receiving chamber along a longitudinal direction; and wherein the cross-sectional dimension is a dimension of a cross-section of the receiving chamber that is perpendicular to the longitudinal direction.

EX13. A heater assembly according to any one of the preceding examples, wherein the heating element comprises a coil wound around a central axis.

EX14. A heater assembly according to example EX13, wherein the coil is deformable to reduce the internal volume of the receiving chamber in the second configuration relative to the first configuration.

EX15. A heater assembly according to example EX13 or EX14, wherein the heater assembly further comprises an actuator configured to deform the coil for transition of the receiving chamber from the first configuration to the second configuration.

EX16. A heater assembly according to any one of examples EX13 to EX15, wherein the wicking element is receivable in the receiving chamber in a direction parallel to the central axis.

EX17. A heater assembly according to any one of examples EX13 to EX16, wherein, in the second configuration of the receiving chamber, at least a first portion of the coil contacts the wicking element when the wicking element is received in the receiving chamber.

EX18. A heater assembly according to example EX17, wherein the coil comprises a second portion different to the first portion.

EX19. A heater assembly according to example EX18, wherein, in the second configuration of the receiving chamber, the second portion of the coil does not contact the wicking element when the wicking element is received in the receiving chamber.

EX20. A heater assembly according to example EX18 or EX19, wherein the second portion of the coil comprises a coating material having a resistivity that is lower than a material of the first portion of the coil.

EX21 . A heater assembly according to any one of examples EX18 to EX20, wherein the second portion of the coil has a cross-sectional dimension that is larger than the first portion.

EX22. A heater assembly according to any one of examples EX13 to EX21 , wherein the coil is a helical coil.

EX23. A heater assembly according to example EX22, wherein the helical coil is axially symmetric.

EX24. A heater assembly according to example EX23 or EX24, wherein the helical coil has a circular cross-section. EX25. A heater assembly according to example EX24, wherein a diameter of the heating element is larger when the receiving chamber is in the first configuration than when the receiving chamber is second configuration.

EX26. A heater assembly according to any one of examples EX13 to EX25, wherein the heating element comprises a first end and a second end.

EX27. A heater assembly according to example EX26, wherein at least one of the first and second end of the heating element is not in the shape of a coil.

EX28. A heater assembly according to any one of examples EX26 to EX27, wherein the first end is rotatable relative to the second end to reduce the internal volume of the receiving chamber in the second configuration relative to the first configuration.

EX29. A heater assembly according to any one examples EX26 to EX28, wherein the heater assembly further comprises an actuator configured to rotate the first end relative to the second end for transition of the receiving chamber from the first configuration to the second configuration.

EX30. A heater assembly according to any of examples EX13 to EX29, wherein the heating element is a helical coil and wherein the number of turns per unit length of the heating element is greater when the receiving chamber is in the second configuration than when the receiving chamber is in the first configuration.

EX31 . A heater assembly according to example EX29, wherein the distance between the first end and the second end of the heating element along the central axis is substantially the same when the receiving chamber is in both the first configuration and the second configuration.

EX32. A heater assembly according to any one of the preceding examples, wherein at least the heating element comprises spaces configured to allow air to pass through the heating element.

EX33. A heater assembly according to any one of the preceding examples, wherein the wicking element is a ceramic wick.

EX34. A heater assembly according to example EX33, wherein the wicking element is a porous ceramic wick.

EX35. A heater assembly according to any one of the preceding examples, wherein the wicking element is cylindrical.

EX36. A heater assembly according to any one of the preceding examples, wherein the heater assembly further comprises a heating element housing.

EX37. A heater assembly according to example EX36, wherein at least the heating element is at least partially contained within the heating element housing.

EX38. A heater assembly according to example EX36 or EX37, wherein, at least when the receiving chamber is in the second configuration, an airflow path is defined between the heating element housing and the heating element. EX39. A heater assembly according to example EX38, wherein the receiving chamber is at least partially defined by a first side of the heating element and the airflow path is at least partially defined by a second side of the heating element, opposite the first side, at least when the receiving chamber is in the second configuration.

EX40. A heater assembly according to any one of examples EX36 to E39, wherein the heater assembly further comprises a user interface element configured to actuate the receiving chamber between the first configuration and the second configuration.

EX41 . A heater assembly according to example EX40, wherein at least a first portion of the heating element housing forms the user interface element.

EX42. A heater assembly according to example EX41 , wherein the heating element comprises a coil wound around a central axis comprising a first end and a second end and wherein the first end of the heating element is fixed to the first portion of the heating element housing.

EX43. A heater assembly according to example EX42, wherein the heating element is not fixed to the first portion of the heating element housing other than at the first end.

EX44. A heater assembly according to any one of examples EX41 to EX43, wherein the heating element housing comprises a second portion and wherein the first portion of the heating element housing is moveable relative to the second portion of the heating element housing.

EX45. A heater assembly according to example EX44, wherein the first portion of the heating element housing is rotatable relative to the second portion of the housing.

EX46. A heater assembly according to example EX44 or EX45, wherein the heating element is a coil wound around a central axis comprising a first end and a second end and the second end of the coil is fixed to the second portion of the heating element housing.

EX47. A heater assembly according to example EX46, wherein the heating element is not fixed to the second portion of the heating element housing other than at the second end.

EX48. A heater assembly according to any one of examples EX44 to EX47, wherein the first and second portions of the housing together form a hollow body containing at least a portion the heating element.

EX49. A heater assembly according to any one of the preceding examples, wherein the heating element is a planar heating element.

EX50. A heater assembly according to example EX49, wherein the heating element is in the form of a sheet.

EX51 . A heater assembly according to example EX49 or EX50, wherein the heating element is fluid permeable.

EX52. A heater assembly according to any one of examples EX49 to EX51 , wherein the heating element comprises a plurality of electrically conductive filaments, a mesh or a sheet comprising a plurality of holes. EX53. A heater assembly according to any one of examples EX49 to EX52, wherein the heating element is moveable to reduce the internal volume of the receiving chamber in the second configuration relative to the first configuration.

EX54. A heater assembly according to example EX53, wherein the heating element is moveable in a direction perpendicular to a longitudinal direction along which the wicking element is receivable in the receiving chamber.

EX55. A heater assembly according to any one of examples EX49 to EX54, wherein the heater assembly further comprises an actuator configured to move at least the heating element for transition of the receiving chamber from the first configuration to the second configuration.

EX56. A heater assembly according to any one of examples EX49 to EX55, further comprising a second planar heating element at least partially defining the receiving chamber.

EX57. A heater assembly according to example EX56, wherein the second planar heating element is moveable relative to the first planar heating element.

EX58. A heater assembly according to example EX56 or EX57, wherein the second planar heating element is opposite the first planar heating element.

EX59. A heater assembly according to any one of examples EX56 to EX58, wherein the distance between the first and second planar heating element is greater in the first configuration of the receiving chamber than the second configuration of the receiving chamber.

EX60. A heater assembly according to any one of the preceding examples, wherein at least the heating element is a susceptor element configured to be inductively heatable.

EX61 . An aerosol-generating device comprising the heater assembly of any one of the preceding examples.

EX62. An aerosol-generating device according to example EX61 , further comprising a power supply.

EX63. An aerosol-generating device according to example EX62, wherein the power supply is electrically connectable to the at least one heating element.

EX64. An aerosol-generating device according to any one of examples EX61 to EX63, wherein the device comprises a device housing.

EX65. An aerosol-generating device according to example EX64, wherein the heater assembly further comprises a heating element housing and at least a portion of the heating element housing is formed by the device housing.

EX66. An aerosol-generating device according to any one of examples EX61 to EX65, wherein the device further comprises an inductor coil.

EX67. An aerosol-generating device according to example EX66, wherein the inductor coil surrounds or is adjacent to the heating element of the heater assembly.

EX68. A cartridge for use with a heater assembly as defined in any one of the preceding examples, the cartridge comprising: a cartridge housing defining a reservoir comprising an aerosol-forming substrate in condensed form; and a wicking element in fluidic communication with the aerosol-forming substrate; wherein a first portion of the wicking element extends from the reservoir and is configured to be received in the receiving chamber of the heater assembly such that the receiving chamber, in the second configuration, contacts the wicking element.

EX69. A cartridge according to example EX68, wherein a first end of the wicking element is exposed to the surrounding air and a second end of the wicking element, opposite to the first end, is in fluidic communication with the aerosol-forming substrate.

EX70. A cartridge according to example EX68 or EX69, wherein the cartridge comprises a mouthpiece portion.

EX71 . A cartridge according to any one of examples EX68 to EX70, wherein the cartridge does not comprise a heating element.

EX72. A cartridge according to any one of examples EX68 to EX71 , wherein the cartridge housing comprises a wall extending from the reservoir and surrounding the wicking element.

EX73. A cartridge according to example EX72, further comprising a deformable membrane that closes an end of the wall of the cartridge housing such that the wicking element is enclosed by the wall and the membrane.

EX74. A cartridge according to example EX73, wherein the membrane is a non-fluid permeable membrane.

EX75. A cartridge according to example EX73 or EX74, wherein the membrane is a flexible and deformable membrane.

EX76. A cartridge according to any one of examples EX73 to EX75, wherein the membrane comprises lines of weakness along which the membrane is breakable.

EX77. A cartridge according to any one of examples EX73 to EX75, wherein the membrane comprises a plurality of elements that together close the end of the wall of the cartridge housing.

EX78. A cartridge according to any one of examples EX68 to EX77, wherein the wicking element is a ceramic wick.

EX79. A cartridge according to example EX78, wherein the wicking element is a porous ceramic wick.

EX80. A cartridge according to any one of examples EX68 to EX77, wherein the wicking element is formed of a resilient material.

EX81 . A cartridge according to any one of examples EX68 to EX80, wherein the wicking element is cylindrical.

EX82. A cartridge according to any one of examples EX68 to EX81 , wherein an airflow path is defined through the cartridge. EX83. A cartridge according to example EX82, wherein the airflow path extends through the cartridge from an air inlet to an air outlet.

EX84. A cartridge according to example EX83, wherein the air outlet is formed in a mouthpiece portion of the cartridge.

EX85. A cartridge according to example EX83 or EX84, wherein the air inlet is annular in shape.

EX86. A cartridge according to example EX85, wherein the annular air inlet surrounds the wicking portion.

EX87. A cartridge according to any one of examples EX83 to EX86, wherein at least a portion of the airflow path extends through the reservoir portion and is annular in shape.

EX88. A cartridge according to example EX87, wherein the portion of the airflow path extending through the reservoir portion is defined by the cartridge housing.

EX89. A cartridge according to any one of examples EX83 to EX88, wherein at least a portion of the airflow path is defined by an outer surface of the wicking element.

EX90. A cartridge according to any one of examples EX68 to EX89, wherein the aerosolforming substrate is a liquid.

EX91. A cartridge according to any one of examples EX68 to EX90, wherein the cartridge further comprises one or more engagement members that are configured to engage the cartridge to a housing of the heater assembly.

EX92. A cartridge according to example EX91 , wherein the one or more engagement members are adjacent to the wicking element.

EX93. A cartridge according to example EX91 or EX92, wherein the one or more engagement members are configured such that the cartridge is configured to engage the heater assembly housing by rotating the cartridge relative to the heater assembly housing.

EX94. A cartridge according to any one of examples EX91 to EX93, wherein the engagement means comprises one or more protrusions configured to be received in a slot of the heater assembly housing.

EX95. A cartridge according to any one of examples EX91 to EX93, wherein the engagement means comprises one or more slot configured to receive one or more protrusions respectively of the heater assembly housing.

EX96. An aerosol-generating system comprising the aerosol-generating device as defined in any one of examples EX61 to EX67 and a cartridge comprising a wicking element configured to be received or receivable in the receiving chamber of the heater assembly.

EX97. An aerosol-generating system according to example EX96, wherein the cartridge is a cartridge as defined in any one of examples EX68 to EX95.

EX98. An aerosol-generating system according to example EX96 or EX97, wherein at least a portion of the wicking element is received or receivable in the receiving chamber of the heater assembly. EX99. An aerosol-generating system according to any one of examples EX96 to EX98, wherein, in the second configuration of the receiving chamber, the heating element is in contact with the wicking element when the wicking element is received in the receiving chamber.

EX100. An aerosol-generating system according to any one of examples EX96 to EX99, wherein the heating element is configured to deform the wicking element when the receiving chamber is in the second configuration.

EX101 . An aerosol-generating system according to any one of examples EX96 to EX100, wherein the cartridge is removably connected from the aerosol-generating device.

EX102. An aerosol-generating system according to any one of examples EX96 to EX101 , wherein the heater assembly comprises a heating element housing and wherein the cartridge is couplable to the heating element housing.

EX103. A method of using the heater assembly as defined in any one of examples EX1 to EX60, the method comprising: receiving a wicking element in the receiving chamber of the heater assembly while the receiving chamber is in first configuration; and transitioning the receiving chamber from the first configuration to the second configuration such that the heating element is in contact with the wicking element.

EX104. A method according to example EX106, wherein the step of transitioning the receiving chamber comprises deforming the heating element.

EX105. A method according to example EX106 or EX107, wherein the heating element comprises a first end, a second end and a coil wound around a central axis and wherein the step of transitioning the receiving chamber comprises rotating the first end relative to the second end.

EX106. A method of using the heater assembly as defined in any one of examples EX1 to EX62, the method comprising: reconfiguring the receiving chamber from the second configuration to the first configuration; and removing a wicking element received in the receiving chamber while the receiving chamber is in the first configuration.

Examples will now be further described with reference to the figures in which:

Figure 1 is a schematic illustration of a first embodiment of an aerosol-generating system;

Figures 2A and 2B are schematic illustrations of a resistive heating element and a wicking element of the aerosol-generating system of Figure 1 , in Figure 2A the resistive heating element is uncoupled from the wicking element and in Figure 2B the resistive heating element is coupled to the wicking element;

Figure 3 is a schematic illustration of the heater assembly of the aerosol-generating system of Figure 1 ;

Figures 4A and 4B are schematic illustrations of an the heater assembly of the aerosolgenerating system of Figure 1 as well as the wicking element, in Figure 4A the resistive heating element is uncoupled from the wicking element and in Figure 4B the resistive heating element is coupled to the wicking element;

Figure 5 is a schematic illustration of a cartridge of the aerosol-generating system of Figure 1 ;

Figure 6 is a flow chart showing a first method of using the aerosol-generating system of Figure 1 ;

Figure 7 is a flow chart showing an second method of using the aerosol-generating system of Figure 1 ;

Figures 8A and 8B are schematic cross-sectional illustrations of a cartridge for use with a second embodiment of an aerosol-generating system;

Figure 9 is a schematic illustration of a third embodiment of an aerosol-generating system; and

Figure 10 is a schematic illustration of a cartridge comprising a heater assembly.

Figure 1 is a schematic illustration of a first embodiment of an aerosol-generating system 100. The aerosol-generating system 100 comprises a cartridge 110. The cartridge 110 comprises a reservoir 112 containing a liquid aerosol-forming substrate 116. The reservoir 112 is defined by the cartridge housing 111. The cartridge 110 further comprises an internal passage 113. A portion of the internal passage 113 is annular. At one end, the cartridge 110 comprises a mouthpiece portion 114. The cartridge 110 comprises a wicking element 120. The wicking element 120 is in fluidic contact with the liquid aerosol-forming substrate 116 in reservoir 112. The wicking element 120 is cylindrical in shape. A first portion 121 of the wicking element extends from the reservoir 112 defined by the cartridge housing 111. The first portion 121 of the wicking element 120 comprises a first end. A second end of the wicking element, opposite the first end, is contained with the cartridge housing 111 and is in fluidic communication with the reservoir 112.

The aerosol-generating system 100 also comprises an aerosol-generating device 150. The aerosol-generating device 150 comprises a controller 154, and a power supply 156 in the form of a rechargeable battery. A device housing 152 of the aerosol-generating device 150 contains both the controller 154 and the power supply 156. The device housing 152 comprises an air inlet 158, and a device airflow passage 115 extending from the air inlet 158.

The aerosol generating device 150 further comprises a heater assembly 130. The heater assembly 130 comprises a resistive heating element 140 configured to heat the wicking element 120. The resistive heating element 140 is formed of a conductive material configured to increase in temperature when a current is passed through it. The resistive heating element 140 comprises a wire wound around a central axis to form a helical coil 141 . The helical coil 141 of the resistive heating element 140 defines a receiving chamber 144. The first portion 121 of the wicking element 120 of the cartridge 110 is received within the receiving chamber 144. The wicking element 120 is receivable into and removable from the receiving chamber 144 along a longitudinal axis that corresponds to the central axis. The heater assembly chamber 144 defined by the helical coil 141 of the resistive heating element 140 has two configurations. In a first configuration, the resistive heating element 140 is uncoupled to the wicking element 120. In a second configuration, the resistive heating element 140 is coupled to the wicking element 120. This is shown in Figures 2A and 2B as well as Figures 4A and 4B. The internal volume of the receiving chamber 144 is larger in the first configuration than in the second configuration.

Figures 2A and 2B are schematic illustrations of the resistive heating element and the wicking element of the first embodiment of the aerosol-generating system.

Figure 2A shows how the helical coil 141 of the resistive heating element 140 is formed by a wire wound around a central axis to form a helical coil. The heater assembly chamber 144 is defined by the helical coil 141 of the resistive heating element 140. The cylindrical wicking element 120 of the cartridge is received in the heater assembly chamber 140 such that at least a first portion 121 of the wicking element 120 is surrounded by the helical coil 141 of the resistive heating element 140 and is received by the heater assembly chamber 144 defined by the helical coil 141 . The helical coil 141 shown in Figures 2A and 2B is a left-handed helical coil, though the helical coil 141 may alternatively be a right-handed helical coil.

The heater assembly chamber 144 defined by the helical coil 141 has a first configuration and a second configuration. Figure 2A shows the heater assembly chamber 144 in the first configuration. Figure 2B shows the heater assembly chamber 144 in the second configuration. As shown in Figures 2A and 2B, the internal volume of the receiving chamber defined by the helical coil 141 is larger in the first configuration than in the second configuration. In particular, a cross-sectional area of the heater assembly chamber 144 is larger in the first configuration than in the second configuration but the length of the heater assembly chamber remains substantially constant. The cross-sectional area of the heater assembly chamber 144 is a cross-section of the receiving chamber taken perpendicularly to the helical axis of the helical coil 141 .

The pitch of the helical coil 141 is larger when the helical coil is in the first configuration than when the helical coil is in the second configuration. The number of turns per unit length of the helical coil 141 is smaller when the helical coil is in the first configuration than when the helical coil is in the second configuration. However, the length of the helical coil is substantially the same when the helical coil is in the first configuration as when the helical coil is in the second configuration

When the heater assembly chamber is in the first configuration, as shown in Figure 2A, the resistive heating element 140 is not in contact with the wicking element 120. In other words, the resistive heating element 140 is uncoupled from the wicking element 120 and the wicking element 120 is freely receivable or removable from the heater assembly chamber 144. When the heater assembly chamber 144 is in the second configuration, as shown in Figure 2B, the resistive heating element 140 is in contact with the wicking element 120. In other words, the resistive heating element 140 is coupled to the wicking element 120. In particular, the helical coil 141 of the resistive heating element 140 is coupled to the first portion 121 of the wicking element 120.

As is shown in Figures 2A and 2B, the resistive heating element 140 comprises a first end 142 and a second end 143. The first and second ends 142, 143 protrude perpendicularly to the central axis of the helical coil 141. The first and second ends 142, 143 comprise a material having a resistance per unit length that is lower than the resistance per unit length of the material of the helical coil 141 . The first and second ends 142, 143 therefore advantageously do not heat up as much as the helical coil 141 when power is provided to resistive heating element 140.

The heater assembly chamber 144 is configurable between the first configuration and the second configuration by deforming the resistive heating element 140. In particular, a first pair of opposing rotational forces 148, represented by the arrows at the first and second ends 142, 143 of the resistive heating element 140, can be applied to the first and second ends 142, 143 to reversibly deform the resistive heating element 140, such that the heater assembly chamber 144 is reconfigurable from the first configuration to the second configuration. A second pair of opposing rotational forces acting in opposite directions to those in the first pair of opposing rotational forces 148, can be applied to the first and second ends 142, 143 to reversibly deform the resistive heating element 140, such that the heater assembly chamber 144 is reconfigurable from the second configuration to the first configuration.

While Figure 2A and 2B show how opposing rotational forces 148 are applied to the first and second ends of the resistive heating element 140 to configure the receiving chamber 144, it is possible for transition of the receiving chamber be applying a rotational force to only one of the first or second ends 142, 143. A rotational force applied to only one of the ends of the resistive heating element 140 still causes rotations of one of the first or second ends 142, 143 relative to the other.

As shown in Figure 1 , the heater assembly 130 further comprises an upper actuator element 132 and a lower actuator element 134. The upper and lower actuator elements 132, 134 together form a housing having a hollow body surrounding the heating element 140. The heater assembly, including the upper lower actuator elements 132, 134, is shown separately from the rest of the aerosol-generating system 100 in Figure 3 which is a schematic perspective illustration. The first end 142 of the resistive heating element 140 is engaged to the upper actuator element 132. In particular, the first end 142 of the resistive heating element 140 passes through an aperture defined in the upper actuator element 132. The second end 143 of the resistive heating element 140 is engaged to the lower actuator element 134. In particular, the second end 143 of the resistive heating element 140 passes through an aperture defined in the lower actuator element 134.

The upper actuator element 132 is axially rotatable relative to the lower actuator element 134. In particular, the actuator element 132 is axially rotatable relative to the lower actuator element 134 about the helical axis of the heating element which is represented by the broken line Figure 3. By rotating the upper actuator element 132 relative to the lower actuator element 134, the first end 142 of the resistive heating element 140 is rotated relative to the second end 143 to elastically deform the resistive heating element 140 and reconfigure the receiving chamber 144 between the first and second configurations. The rotational forces applied to upper and lower actuator elements 132, 134 for transition of the receiving chamber 144 between the first and second configurations are shown by arrows 192, 194 respectively. While Figure 3 shows both lower and upper actuator elements 132, 134 as being rotatable, it is enough for only one of the actuator elements to be rotatable relative to the other.

Figure 4A shows a schematic cross-section of the heater assembly of Figure 3 but in which the wicking element 120 is received in the heater assembly chamber 144. In Figure 4A, the heater assembly chamber 144 is in the first configuration. The upper actuator element 132 and the lower actuator element 134 surround the resistive heating element 140. The second end portion 143 protrudes out of the lower actuator element 134. As Figure 4A a cross-sectional view, only the second end is visible.

Figure 4B shows the heater assembly with the heater assembly chamber 144 in the second configuration. As in Figure 2B, the wicking element 120 is received in the heater assembly chamber in the second configuration 146, and the resistive heating element 140 is contacting the wicking element 120. An air flow path 147 is defined by the annular space between the helical coil 141 and the lower actuator element 134 and then between the helical coil 141 and the upper actuator element 132. The annular space itself between the helical coil 141 and the lower actuator element 134 and then between the helical coil 141 and the upper actuator element 132 defines an aerosol generating chamber. In use of the heater assembly, vapourised aerosol-forming substrate enters the aerosol generating chamber, escaping from the wicking element 120. The vapourised aerosol-forming substrate intermixes with air in the airflow path 147 to cool and condense into an aerosol which before delivery to the user.

Figure 5 shows a schematic illustration of the cartridge 110 separately from the aerosolgenerating device. The wicking element 120 is received in a wicking element cavity 301 defined by a wicking element wall 303. The wicking element wall 303 is integrally formed with the cartridge housing 111. The second end of the wicking element 120 is in fluidic communication with the liquid aerosol-forming substrate 116 contained in reservoir 112. The reservoir 112 is defined by the cartridge housing 111. The internal passage 113 is defined by the cartridge housing 111 and the wicking element wall 303. A first portion 121 of the wicking element 120 protrudes from the cartridge housing 111 , such that the first portion 121 of the wicking element 120 is outside of the boundary formed by the cartridge housing 111. The first portion 121 of the wicking element 120 may, therefore, be receivable and removable from the receiving chamber 144 of the heater assembly 130 of the aerosol generating device 150.

Figure 6 shows a schematic of a first method of using the aerosol-generating system 100. The method comprises the step 801 of receiving the wicking element 120 in the heater assembly chamber 144 in the first configuration. As above, in the first configuration, the wicking element 120 is freely receivable and removable from the resistive heating element 140 in the first configuration, the wicking element 120 and the resistive heating element 140 are not coupled. So it is straightforward to receive the wicking element 120 the heater assembly chamber 144 when the heater assembly chamber 144 is in the first configuration.

The method further comprises step 802 of rotating a first end 142 of the resistive heating element 140 relative to a second end 143 of the resistive heating element 140 so as to deform the resistive heating element 140 such that the resistive heating element 140 is in contact with the wicking element 120. The wicking element 120 is therefore in the heater assembly chamber 144 in the second configuration. In step 802 the heater assembly chamber 144 is therefore reconfigured from the first configuration to the second configuration.

The method further comprises step 803 of using the aerosol-generating system 100 while the heater assembly chamber 144 is in the second configuration. The step 802 of transitioning the heater assembly chamber 144 from the first configuration to the second configuration automatically sends an activation signal to the controller 154 to activate the device 150. Activation of the device 150 results in power being supplied from the battery 156 to the resistive heating element 140. The battery 156 is connected to the first and second ends 142, 143 of the resistive heating element 140 via wires and suitable electrical contacts, not shown in the figures. This causes a current to flow through the resistive heating element 140, thereby resistively heating the resistive heating element 140.

In other examples, the device 150 is not activated immediately in response to the heater assembly chamber 144 being reconfigured from the first configuration to the second configuration. Instead a user may press a button (not shown) on the aerosol-generating device 150 which sends the activation signal to the controller 154. In other examples, an air flow sensor, or pressure sensor, is located in the aerosol-generating system 100 and electrically connected to the controller 154. The air flow sensor, or pressure sensor, detects that a user is puffing on the mouthpiece portion 114 and sends a signal to the controller 154 to provide power to the resistive heating element 140.

During step 803, a user can puff on the mouthpiece portion 114 of the cartridge 110. As the user puffs on the mouthpiece portion 114 of the cartridge 110, air is drawn into the air inlet 158. An airflow path is defined between the air inlet 158 and the mouthpiece portion 114, passing through the device airflow passage 115, the heater assembly 130, and the internal passage 113 of the cartridge 110. In particular, the airflow path passes over the wicking element 120. Liquid aerosol-forming substrate 116 in the reservoir 112 is drawn into the wicking element 120 by capillary forces. The liquid aerosol-forming substrate 116 in the wicking element 120 is subsequently heated and vaporised by the resistive heating element 140 to generate a vapour. The airflow entrains the vapour formed by the resistive heating element 140 heating liquid aerosol-forming substrate 116 in the wicking element 120. This entrained vapour then cools and condenses to form an aerosol. This aerosol is subsequently drawn out of the system via the internal passage 113 of the cartridge 110 and the mouthpiece portion 114 by the user.

Because the resistive heating element 140 is in contact with the wicking element 120 in the second configuration, the wicking element 120 (and so the liquid aerosol-forming substrate 116) is efficiently heated by the resistive heating element 140.

The method further comprises the fourth step 804 of transitioning the heater assembly chamber 144 from the second configuration to the first configuration. After the fourth step 804, the resistive heating element 140 is decoupled from the wicking element 120. As such the cartridge 110 can be removed from the aerosol-generating device 150 and replaced following step 804. Alternatively, the steps 802 to 804 can be repeated for subsequent usage sessions until the liquid aerosol-forming substrate 116 of the cartridge 110 is depleted.

The heater assembly chamber 144 has been described as having a first configuration and a second configuration. The heater assembly chamber 144 also has a third configuration (not shown in the Figures). In the third configuration, the receiving chamber 144 has a smaller internal volume than in both the first and the second configuration. As such, the resistive heating element 140 applies a compressive force on the wicking element 120 when the receiving chamber 144 is in the third configuration. In some embodiments, the wicking element 120 comprises a compressible material. So, in the third configuration, the wicking element compressible material is compressed.

Thus, in some embodiments, step 802 of the method comprises rotating a first end 142 of the resistive heating element 140 relative to a second end 143 of the resistive heating element so as to deform the heating element such that the receiving chamber is in the third configuration and then rotating a first end 142 of the resistive heating element 140 relative to a second end 143 of the resistive heating element so as to deform the resistive heating element such that the resistive heating element is in contact with the wicking element.

Configuring the heater assembly chamber 144 in the third configuration before the second configuration forces aerosol-forming substrate contained in the wicking element 120 outside of the wicking element 120. This aerosol-forming substrate is then quickly heated and vaporised during step 803.

In some embodiments, step 802 comprises repeatedly rotating a first end 142 of the resistive heating element 140 relative to a second end 143 of the resistive heating element 140 to configure the heater assembly chamber 144 from the second configuration to the third configuration and back again. This advantageously results in a pumping effect in which liquid aerosol-forming substrate 116 is drawn from the second end of the wicking element 120 in fluidic communication with the reservoir 112 to the first end of the wicking element 120 received in the heater assembly chamber 144.

In some embodiments, step 803 of the method comprises rotating a first end 142 of the resistive heating element relative 140 to a second end 143 of the resistive heating element 140 so as to deform the resistive heating element 140 such that the heater assembly chamber 144 is in the third configuration. This is performed towards the end of step 803 to force remaining substrate contained in the wicking element 120 out of the wicking element 120 to be vaporised. This can reduce or minimize cross-contamination of liquid aerosol-forming substrate 116 in the cartridge 110 if the liquid aerosol-forming substrate 116 is replaced.

Figure 7 shows a schematic of a second method of using the heater assembly in accordance with the present invention. The method comprises the first step 901 of rotating a first end 142 of the resistive heating element 140 relative to a second end 143 of the resistive heating element 140 as to deform the resistive heating element 140 such that the resistive heating element 140 is not in contact with the wicking element 120. The wicking element 120 is therefore in the heater assembly chamber 144 in the first configuration. The first step 901 therefore includes transitioning the heater assembly chamber 144 from the second configuration to the first configuration. The method further comprises the second step 902 of removing the wicking element 120 received in the heater assembly chamber 144 while the receiving chamber is in the first configuration.

Figures 8A and 8B show schematic illustrations of a cartridge 110 in accordance with the present invention. The cartridge 110 is similar to that shown in Figure 3, and so will be described with respect to the differing features only. The cartridge housing 111 further comprises a cartridge housing wall 171 extending downwardly from the reservoir 112 and at an opposite end of the cartridge to the mouthpiece portion 114. The cartridge housing wall 171 extends further down than the wicking element 120, and partially defines a cavity 172. The cartridge housing wall 171 is integrally formed with the rest of the cartridge housing 111. The first portion 121 of the wicking element 120 is contained within the cavity 172. The cavity 172 is configured such that a portion of the heater assembly 130 of aerosol generating device 150 can be received within cavity 172. When a portion of the heater assembly 130 is received in the cavity 130, the cartridge housing wall 171 surrounds heater assembly 130.

The cartridge 110 further comprises a membrane 170. The membrane 170 also partially defines cavity 172. As shown in Figure 8A, the membrane 170 closes an end of the cavity 172. The combination of the membrane 170 and the cartridge housing wall 171 protects the wicking element prior to the cartridge being coupled to heater assembly 130.

The membrane 170 comprises a plurality of flexible elements 173. When a portion of the heater assembly 130 of aerosol generating device 150 is received within the cavity 172, the plurality of flexible elements deform upwards, towards the reservoir 112, and into the cavity 172. When the heater assembly 130 of aerosol generating device 150 is removed from cartridge housing wall cavity 172, for example, when the liquid aerosol-forming substrate 116 is depleted, the plurality of flexible elements 173 return to their undeformed state, as shown in Figure 7A.

Alternatives to membrane 170 to protect wicking element 120 may also be provided. For example, membrane 170 may instead be a breakable membrane, which breaks or deforms when heater assembly 130 of aerosol generating device 150 is received within cartridge housing wall cavity 172. Such a breakable membrane does not return to an undeformed state once heater assembly 130 of aerosol generating device 150 is removed from cartridge housing wall cavity 172.

Figure 9 shows a schematic illustration of an aerosol-generating system 700 in accordance with the present invention. The aerosol-generating system 700 is similar to that shown in Figure 1 , so will only be described with respect to the differing features only. Heater assembly 730 of aerosol generating device 750 further comprises an inductor coil 795. Instead of a resistive heating element, heater assembly 730 of aerosol generating device 750 further comprises a susceptor element 740. The susceptor element 740 comprises a helical susceptor coil in the same form as the helical coil 141 of resistive heating element 140 in Figures 1 to 4, including comprising end portions protruding through upper actuator element 132 and lower actuator element 134. Instead of being directly resistively heated however, the susceptor element 740 is heated by induction. Alternating currents are applied to inductor coil 795, which generates a magnetic field. The susceptor element 740 is heated by eddy currents and hysteresis losses induced by the generated magnetic field.

Figure 10 is a schematic illustration of a cartridge 810 comprising a heater assembly 830 in accordance with the present invention.

A portion of the cartridge 810 is similar to the cartridge 110 described with respect to the aerosol-generating system shown in Figure 1. That is, the cartridge 810 comprises a reservoir

112 defined by the cartridge housing 111 and containing a liquid aerosol-forming substrate 116. The cartridge 810 further comprises an internal passage 113. A portion of the internal passage

113 is annular. At one end, the cartridge 810 comprises a mouthpiece portion 114. The cartridge 810 comprises a wicking element 820. The wicking element 820 is in fluidic contact with the liquid aerosol-forming substrate 116 in reservoir 112. The wicking element 820 is cylindrical in shape. A first portion 821 of the wicking element extends from the reservoir 112 defined by the cartridge housing 811 . The first portion 821 of the wicking element 820 comprises a first end. A second end of the wicking element, opposite the first end, is contained with the cartridge housing 111 and is in fluidic communication with the reservoir 112.

Where this cartridge 810 differs from the cartridge 110 described with respect to the aerosol-generating system shown in Figure 1 , is that the cartridge 810 further comprises a heater assembly 830. The heater assembly 830 is identical to that disclosed in the first aspect of the disclosure and described with respect to the aerosol-generating system shown in Figure 1 . That is, the heater assembly 830 comprises a resistive heating element 140 configured to heat the wicking element 820. The resistive heating element 140 is formed of a conductive material configured to increase in temperature when a current is passed through it. The first portion 821 of the wicking element 820 of the cartridge 810 is received within a receiving chamber defined by a helical coil of the resistive heating element 840. The wicking element 820 may be removed from or inserted into the heater assembly 830 by the user when the receiving chamber is in the first configuration.