CN121463890A

CN121463890A - Aerosol generating system with airflow chamber

Info

Publication number: CN121463890A
Application number: CN202480046265.7A
Authority: CN
Inventors: O·达伊奥格鲁
Original assignee: Philip Morris Products SA
Current assignee: Philip Morris Products SA
Priority date: 2023-07-24
Filing date: 2024-07-18
Publication date: 2026-02-03
Also published as: WO2025021664A1

Abstract

An aerosol generation system (10) includes: a cylinder (12) and a device (14), the cylinder including: a cylinder housing; a liquid reservoir (25) configured to hold a liquid aerosol forming matrix (26); and a heating element (31) configured to heat the liquid (26) from the liquid reservoir (25), the device including: a device housing (38) defining a device cavity (40) configured to receive a portion of the cylinder (12); wherein: when the cylinder (12) When the portion is received in the device cavity (40), the aerosol generation system (10) includes an airflow path defined between an air inlet (48) and an air outlet (22); when the portion of the cylinder (12) is received in the device cavity (40), an airflow cavity (51) is located in the airflow path, the airflow cavity (51) being defined between the cylinder housing and the device housing (38); and the device (14) includes a pressure sensor (52) arranged to detect the pressure in the airflow cavity (51).

Description

Aerosol generating system with airflow chamber

The present disclosure relates to an aerosol-generating system comprising a cartridge and a device. In particular, the present invention relates to an aerosol-generating system comprising an airflow chamber located in an airflow path, the airflow chamber being defined between a housing of a cartridge and a housing of a device.

Some known aerosol-generating systems comprise a cartridge holding a liquid aerosol-forming substrate and an aerosol-generating device configured to receive the cartridge, wherein the system is generally configured to generate an aerosol from the liquid aerosol-forming substrate by heating the liquid aerosol-forming substrate when the cartridge is received in the aerosol-generating device.

In some known systems, the aerosol-generating device comprises a power source (such as a battery) and a controller, and the cartridge comprises a heating element. The power supply and controller of the aerosol-generating device are configured to supply power to the heating element for heating the heating element to heat the liquid aerosol-forming substrate. In use, when power is supplied from the power source to the heating element, the heating element heats the liquid aerosol-forming substrate, which releases volatile components that condense to form an aerosol that is inhalable by a user.

In some known systems, the aerosol-generating system comprises an induction heating assembly. In some of these known systems, the aerosol-generating device comprises a power source (such as a battery), a controller, and an inductor coil, and the cartridge comprises a susceptor element. The inductor coil generates a varying magnetic field when supplied with a varying current and the susceptor element is heated when it is arranged in the varying magnetic field. In use, the cartridge is inserted into the cavity of the aerosol-generating device and a varying current is supplied from the power supply to the inductor coil to generate a varying magnetic field. The varying magnetic field penetrates the susceptor element, thereby heating the susceptor element, which in turn heats the aerosol-forming substrate, thereby releasing volatile components that condense to form an aerosol that is inhalable by a user.

It is desirable to provide an aerosol-generating system having an accurate and reliable way to detect when a user draws on the aerosol-generating system so that the aerosol-generating system can accurately control when power is supplied to the heating element or the induction heating assembly. It is also desirable to provide an aerosol-generating system that is capable of accurately detecting various characteristics of a user's puff on the aerosol-generating system.

According to the present disclosure, an aerosol-generating system is provided. The aerosol-generating system may comprise a cartridge and a device. The cartridge may include a cartridge housing. The cartridge may include a liquid reservoir configured to hold a liquid aerosol-forming substrate. The cartridge may include a heating element configured to heat liquid from the liquid reservoir. The device may include a device housing defining a device cavity configured to receive a portion of the cartridge. When a portion of the cartridge is received in the device cavity, the aerosol-generating system may comprise an airflow path defined between the air inlet and the air outlet. The airflow chamber may be located in the airflow path when a portion of the cartridge is received in the device chamber. An airflow chamber may be defined between the cartridge housing and the device housing. The device may comprise a pressure sensor arranged to detect the pressure in the airflow chamber.

According to a preferred embodiment of the present disclosure, there is provided an aerosol-generating system comprising a cartridge and a device. The cartridge includes a cartridge housing, a liquid reservoir configured to hold a liquid aerosol-forming substrate, and a heating element configured to heat liquid from the liquid reservoir. The device includes a device housing defining a device cavity configured to receive a portion of the cartridge. When a portion of the cartridge is received in the device cavity, the aerosol-generating system comprises an airflow path defined between the air inlet and the air outlet. When a portion of the cartridge is received in the device cavity, the airflow cavity is located in the airflow path, the airflow cavity being defined between the cartridge housing and the device housing. The device comprises a pressure sensor arranged to detect the pressure in the airflow chamber.

Providing the aerosol-generating system with a pressure sensor configured to detect a pressure in an airflow path through the aerosol-generating system may enable the aerosol-generating system to detect when a user draws on the aerosol-generating system. Advantageously, providing an airflow chamber in the airflow path of the aerosol-generating system (wherein the airflow chamber is defined between a portion of the cartridge housing and a portion of the device housing) may enable one or both of the cartridge and the device to be made smaller or more compact than systems in which the airflow chamber is formed entirely by the cartridge housing or entirely by the device housing.

As used herein, an "aerosol-generating system" refers to a system that interacts with an aerosol-forming substrate to generate an aerosol. Preferably, the aerosol-generating system is a system that interacts with the aerosol-forming substrate to generate an inhalable aerosol that is inhalable directly into the user's lungs through the user's mouth. As used herein, an aerosol-generating system includes a cartridge and a device.

As used herein, "aerosol-forming substrate" refers to a substrate capable of releasing volatile compounds that can form an aerosol. Such volatile compounds may be released by heating the aerosol-forming substrate. Unless otherwise indicated, in the present disclosure, aerosol-forming substrate refers to a liquid aerosol-forming substrate typically stored in a reservoir in a cartridge.

As used herein, the term "cartridge" refers to an article comprising an aerosol-forming substrate capable of releasing volatile compounds that can form an aerosol. The cartridge may be disposable.

As used herein, the terms "upstream" and "downstream" are used to describe the relative positions of components or portions of components of an aerosol-generating system. The terms upstream and downstream are relative to the direction of the airflow or aerosol flow through the aerosol-generating system when a user draws on the air outlet of the airflow path through the aerosol-generating system. The air outlet of the air flow path is downstream of the air inlet of the air flow path. The airflow chamber of the airflow path is downstream of the air inlet of the airflow path. The airflow chamber of the airflow path is upstream of the air outlet of the airflow path. The air inlet of the air flow path may be upstream of the air outlet of the air flow path.

As used herein, the term "suction" is used to describe the action of a user of an aerosol-generating system drawing on an air outlet of an airflow path to receive and inhale an aerosol generated by the aerosol-generating system.

As used herein, "length" refers to the largest dimension of a feature in the longitudinal direction of the feature.

As used herein, "width" or "diameter" refers to the largest dimension of a feature in the lateral direction of the feature. The transverse direction is perpendicular to the longitudinal direction.

As used herein, "thickness" and "depth" refer to the largest dimension of a feature in a direction perpendicular to the longitudinal direction of the feature and perpendicular to the lateral direction of the feature.

In some preferred embodiments, when air is drawn through the airflow path between the air inlet and the air outlet, the pressure in the airflow path has a minimum value in the airflow chamber. In other words, as air is drawn through the airflow path, a region of minimum pressure through the airflow path is at the airflow cavity.

In some particularly preferred embodiments, the flow restriction is arranged in the airflow path between the air inlet and the airflow chamber. The flow restriction may be configured to cause a pressure drop in the airflow chamber as air is drawn through the airflow path. The pressure drop at the airflow chamber may be such that the pressure in the airflow path has a minimum value in the airflow chamber.

Advantageously, detecting the pressure in the airflow chamber in the airflow path after the flow restriction, and in particular the pressure at the point of minimum pressure along the airflow path, may provide a more accurate detection of suction by the aerosol-generating system. Advantageously, detecting the pressure in the airflow chamber in the airflow path after the flow restriction, and in particular the pressure at the point of minimum pressure along the airflow path, may provide a more rapid detection of suction by the aerosol-generating system. Detecting the pressure after the flow restriction, and in particular the pressure at the point of minimum pressure along the airflow path, may enable detection of a pressure drop caused by the flow restriction, which may be used to detect when a user is drawing on the aerosol-generating system.

Advantageously, detecting the pressure of the airflow path after the flow restriction may provide more accurate information about the user's suction on the aerosol-generating device. Detecting the pressure after the flow restriction may enable detection of a pressure drop caused by the flow restriction, which may be used to determine a suction characteristic (such as the volume of air sucked through the flow restriction).

The flow restriction may be any suitable flow restriction that causes a pressure drop in the airflow path that is measurable by the pressure sensor when a user draws on the aerosol-generating system.

When a user inhales on the aerosol-generating system, they will experience a resistance to inhalation. This resistance can be quantified as a measure of the pressure drop across the aerosol-generating system at a given volumetric flow rate through the system, known as the draw Resistance (RTD). Acceptable RTD is typically in the range of 60 to 100 millimeters of water (mmWg) for consumer comfort.

The Resistance To Draw (RTD) of an aerosol-generating system or an airflow path, or a cartridge, or any other component of an aerosol-generating system is measured according to ISO 6565-2015 unless otherwise specified. RTD refers to the pressure required to force air through the entire length of the component. The term "pressure drop" or "suction resistance (DRAW RESISTANCE)" of a component may also refer to "suction resistance (RESISTANCE TO DRAW)". Such terms generally refer to measurements made in accordance with ISO 6565-2015, which are typically made in the test at an ambient temperature of about 22 degrees celsius, a pressure of about 101 kilopascals (about 760 torr), and a relative humidity of about 60% at the output or downstream end of the measured component at a volumetric flow rate of about 17.5 milliliters per second.

The flow restriction may be configured to cause a pressure drop of at least 70 pascals (Pa), at least 80 pascals (Pa), at least 90 pascals (Pa), at least 100 pascals (Pa) (10 millimeters of water), at least 150 pascals (Pa), at least 200 pascals (Pa), at least 250 pascals (Pa), or at least 300 pascals (Pa) during typical puffs of a user.

The flow restriction may be arranged at any suitable location in the airflow path. Preferably, the flow restriction is arranged immediately upstream of the airflow chamber. In some embodiments, the flow restriction may be spaced apart from the airflow chamber.

In some embodiments, the aerosol-generating device comprises a flow restriction. In some of these embodiments, a portion of the device housing defines a flow restriction.

In some embodiments, a flow restriction is defined between the cartridge housing and the device housing. When a portion of the cartridge is received in the device cavity, a flow restriction may be defined between the cartridge housing and the device housing. In some embodiments, at least a portion of the surface of the cartridge housing defines at least a portion of the surface of the flow restriction. In some embodiments, at least a portion of a surface of the device housing defines at least a portion of a surface of the flow restriction.

The flow restriction may be a portion of the airflow path having a width less than the width of the airflow chamber. The flow restriction may be a portion of the airflow path having a width that is smallest in any portion of the airflow path.

The flow restriction may be a portion of the airflow path having a cross-sectional area that is smaller than the cross-sectional area of the airflow chamber. The flow restriction may be a portion of the airflow path having a smallest cross-sectional area in any portion of the airflow path.

The flow restriction may have any suitable width. The flow restriction may have a width of between 0.15 mm and 0.8 mm.

The flow restriction may have any suitable depth. The flow restriction may have a depth of between 0.3 mm and 1.2 mm.

The flow restriction may have any suitable length. The flow restriction may have a length of between 1 and 2 mm.

The flow restriction may have any suitable cross-sectional area. The flow restriction may have a cross-sectional area between 0.045 square millimeters and 1 square millimeter.

The flow restriction may comprise a narrow portion of the airflow path through the aerosol-generating device, the narrow portion of the airflow path having a width or diameter that is less than a width or diameter of at least one of a portion of the airflow path immediately before the flow restriction and a portion of the airflow path immediately after the flow restriction. The flow restriction may comprise a narrow portion having a width or diameter that is smaller than the width or diameter of the airflow path immediately before the flow restriction. The flow restriction may comprise a narrow portion having a width or diameter smaller than the diameter of the airflow path immediately after the flow restriction. The flow restriction may comprise a plurality of narrow portions, each having a width or diameter that is less than the width or diameter of the airflow path immediately before the flow restriction and the width or diameter of the airflow path immediately after the flow restriction.

Preferably, the flow restriction comprises a narrow portion of the airflow path having a minimum width or diameter of the airflow path.

The flow restriction may comprise a narrow portion of the airflow path through the aerosol-generating device, the narrow portion of the airflow path having a cross-sectional area that is smaller than a cross-sectional area of at least one of a portion of the airflow path immediately before the flow restriction and a portion of the airflow path immediately after the flow restriction. The flow restriction may comprise a narrow portion having a cross-sectional area that is smaller than the cross-sectional area of the airflow path immediately before the flow restriction. The flow restriction may comprise a narrow portion having a cross-sectional area smaller than the cross-sectional area of the airflow path immediately after the flow restriction. The flow restriction may comprise a plurality of narrow portions, each having a cross-sectional area that is smaller than the cross-sectional area of the airflow path immediately before the flow restriction and the cross-sectional area of the airflow path immediately after the flow restriction.

Preferably, the flow restriction comprises a narrow portion of the airflow path having a minimum cross-sectional area of the airflow path.

The aerosol-generating system comprises an airflow chamber in the airflow path. The airflow chamber is located in the airflow path. When a portion of the cartridge is received in the device cavity, an airflow cavity is defined between the cartridge housing and the device housing. In some embodiments, at least a portion of the surface of the cartridge housing defines at least a portion of the surface of the airflow chamber. In some embodiments, at least a portion of a surface of the device housing defines at least a portion of a surface of the airflow chamber. The airflow chamber may be of any suitable size and shape.

The aerosol-generating system comprises a heating element. Preferably, at least a portion of the surface of the heating element is arranged to contact air in the airflow path. The heating element may be arranged at any suitable location in the airflow path. A portion of the surface of the heating element may form a portion of the surface of the airflow path. A portion of the heating element may be disposed in the airflow path. In some preferred embodiments, the heating element is arranged between the airflow chamber and the air outlet. In some preferred embodiments, the heating element is arranged after the airflow chamber. In other words, the heating element is preferably arranged downstream of the airflow chamber. Advantageously, arranging the heating element downstream of the airflow chamber may reduce the instances where vapor or aerosol generated at the heating element passes through the airflow chamber and contacts the pressure sensor. This may help to protect the pressure sensor from damage due to contact with hot vapor or aerosol.

In some embodiments, the aerosol-generating device may comprise two flow restrictions, a first flow restriction as described above, and a second flow restriction after the airflow chamber. The second flow restriction may be arranged between the airflow chamber and the air outlet. The second flow restriction may be arranged downstream of the airflow chamber. Thus, the pressure sensor may be arranged to detect a pressure drop in the airflow path caused by the first flow restriction instead of the second flow restriction. The second flow restriction may help prevent vapour or aerosol generated in the device cavity from flowing back into the airflow cavity between puffs on the aerosol-generating device. Thus, the second flow restriction may help keep the pressure sensor clean by keeping the pressure sensor away from the generated vapors and aerosols.

The pressure sensor may comprise any suitable type of pressure sensor. The pressure sensor may be an absolute pressure sensor configured to determine an absolute pressure in the airflow chamber. The pressure sensor may be a gauge pressure sensor configured to detect a relative pressure in the airflow chamber as compared to an ambient pressure adjacent the aerosol-generating system. The pressure sensor may be a differential pressure sensor configured to detect a pressure difference between the airflow chamber and another first location in the airflow path. The pressure sensor may be a capacitive pressure sensor. The pressure sensor may be a piezoresistive pressure sensor. The pressure sensor may be a strain gauge. Preferably, the pressure sensor is a microelectromechanical system (MEMS) pressure sensor. Advantageously, the MEMS pressure sensor may be small enough to fit into the aerosol-generating device without significantly increasing the size of the aerosol-generating device. An example of a suitable absolute pressure sensor is the MEMS nano-pressure sensor LPS22HBTR manufactured by STMicroelectronics, which has an operating pressure between about 26 kilopascals (kPa) and about 126 kilopascals (kPa) and dimensions of 2 millimeters by 0.76 millimeters.

The pressure sensor is configured to detect a pressure in the airflow chamber of the airflow path.

In some embodiments, the pressure sensor is configured to detect a differential pressure in the airflow path. In some embodiments, the pressure sensor is configured to detect a pressure in the airflow path before the airflow chamber and a pressure in the airflow chamber. In some of these embodiments, the pressure sensor includes a first pressure sensor configured to detect a pressure in the airflow chamber and a second pressure sensor configured to detect a pressure before or upstream of the airflow chamber.

In some embodiments including a flow restriction between the air inlet and the airflow chamber, the pressure sensor is configured to detect a pressure in the airflow path before or upstream of the flow restriction, and a pressure in the airflow chamber. In some of these embodiments, the pressure sensor includes a first pressure sensor configured to detect a pressure in the airflow chamber and a second pressure sensor configured to detect a pressure before or upstream of the flow restriction.

Advantageously, differential pressure measurements made between two locations in the airflow path may be unaffected by local environmental conditions such as altitude and humidity. Thus, in the case of differential pressure measurements, the pressure sensor may not need to be recalibrated for use in different environments (such as at different altitudes).

When a portion of the cartridge is received in the device cavity, the aerosol-generating system comprises an airflow path defined between the air inlet and the air outlet.

The air inlet may be any suitable air inlet.

In some embodiments, the device comprises an air inlet. In some embodiments, the cartridge includes an air inlet. In some preferred embodiments, the air inlet is defined between the cartridge and the device when a portion of the cartridge is received in the device cavity.

The air inlet may comprise a single air inlet. The air inlet may comprise a plurality of air inlets. The air inlets may comprise any suitable number of air inlets. For example, the air inlets may include one, two, three, four, five, or six air inlets.

The air outlet may be any suitable air outlet.

In some embodiments, the device comprises an air outlet. In some preferred embodiments, the cartridge includes an air outlet.

The air outlet may comprise a single air outlet. The air outlet may comprise a plurality of air outlets. The air outlets may comprise any suitable number of air outlets. For example, the air outlets may include one, two, three, four, five, or six air outlets.

In some embodiments, the device includes a connection end. The device lumen may be disposed at the connection end of the device.

In some embodiments, the cartridge includes a mouth end and a connection end opposite the mouth end. The connection end may be configured to be received by the device lumen. The connection end may be the portion of the cartridge that is received by the device cavity. In some preferred embodiments, the air outlet of the air flow path is arranged at the mouth end of the cartridge. The mouth end of the cartridge may be configured for a user to inhale on the mouth end to inhale an aerosol generated by the aerosol-generating system.

When a portion of the cartridge is received in the device cavity, a portion of the connecting end of the cartridge may form a portion of the airflow cavity. When a portion of the cartridge is received in the device cavity, a portion of the surface of the connection end of the cartridge may form at least a portion of the surface of the airflow cavity.

Where the aerosol-generating system comprises a flow restriction and the flow restriction is defined between the device and the cartridge, a portion of the connecting end of the cartridge may form a portion of the flow restriction when a portion of the cartridge is received in the device cavity. When a portion of the cartridge is received in the device cavity, a portion of a surface of the connection end of the cartridge may form at least a portion of a surface of the flow restriction.

In some preferred embodiments, the portion of the airflow path between the air inlet and the airflow chamber is defined between the cartridge housing and the device housing. In some of these preferred embodiments, the portion of the airflow path between the air inlet and the airflow chamber extends along the length of the device chamber. Advantageously, arranging a portion of the airflow path between the device cavity and the outer surface of the device housing may reduce the temperature of the outer surface of the device housing when the aerosol-generating system is in use, as the airflow in this portion of the airflow path isolates the device cavity from the outer surface of the device housing. Advantageously, arranging a portion of the airflow path between the device housing and the cartridge housing can help prevent condensation on the outer surface of the device housing, which may be caused by a temperature differential between the outer surface of the device housing and the external environment, by isolating the outer surface of the device housing from heat generated around the device cavity by generating aerosol.

The device includes a device lumen. The device cavity is configured to receive a portion of the cartridge. The device lumen may be of any suitable size and shape.

In some embodiments, the device cavity includes an open end that enables a portion of the cartridge to be received in the device cavity and a substantially closed end opposite the open end.

The device cavity may interface with the airflow path at or around the substantially closed end. The airflow path may interface with the device cavity at or around the substantially closed end of the device cavity. In other words, the device cavity may intersect the airflow path at or around the substantially closed end. When a portion of the cartridge is received in the device cavity, a portion of the device cavity at or around the substantially closed end may form a portion of the airflow cavity. When a portion of the cartridge is received in the device cavity, a portion of the surface of the device cavity at or around the substantially closed end of the device cavity may form at least a portion of the surface of the airflow cavity.

Where the aerosol-generating system comprises a flow restriction and the flow restriction is defined between the device and the cartridge, the portion of the device cavity at or around the substantially closed end may form part of the flow restriction when a portion of the cartridge is received in the device cavity. When a portion of the cartridge is received in the device cavity, a portion of the surface of the device cavity at or around the substantially closed end may form at least a portion of the surface of the flow restriction.

Where the aerosol-generating system comprises a flow restriction, the flow restriction may be arranged at or around the substantially closed end of the device cavity. Where the device includes a flow restriction, the flow restriction may be disposed below or beneath the substantially closed end of the device cavity. Where the device includes a flow restriction, the flow restriction may be disposed adjacent or in close proximity to the device lumen. The flow restriction may be disposed adjacent or in close proximity to the substantially closed end of the device cavity.

The pressure sensor may be arranged at any suitable location in the device. The pressure sensor may be arranged at or around the substantially closed end of the device. In some embodiments, a portion of the surface of the pressure sensor may form a portion of the surface of the device cavity.

In some preferred embodiments, the pressure sensor is located in a pressure sensor cavity in the device. The pressure sensor cavity may be arranged below or underneath the device cavity. The pressure sensor cavity may be disposed below or beneath the substantially closed end of the device cavity.

The pressure sensor cavity may have any suitable shape or size.

In some preferred embodiments, an additional airflow path is provided between the airflow chamber and the pressure sensor chamber. The additional airflow path may enable air to flow between the airflow chamber and the pressure sensor chamber.

In some preferred embodiments, the cartridge comprises two parts, a first part and a second part, wherein the second part is movable relative to the first part. In some of these preferred embodiments, the first part comprises a liquid reservoir and the second part comprises a heating element. The first part and the second part may be movable between a storage position and a use position. In the storage position, the liquid reservoir in the first part of the cartridge may be isolated from the heating element in the second part of the cartridge. Isolating the liquid reservoir from the heating element may prevent liquid held in the liquid reservoir from reaching the heating element. Preventing liquid from reaching the heating element may reduce the likelihood of liquid held in the reservoir leaking out of the cartridge. In the use position, a liquid path from the liquid reservoir to the heating element may be provided. Providing a liquid path from the liquid reservoir to the heating element may enable liquid from the liquid reservoir to reach the heating element. In the use position, the heating element may be positioned to heat liquid from the liquid reservoir to generate an aerosol.

The cartridge may be configured to prevent liquid held in the liquid reservoir from reaching the heating element when the first part and the second part are in the storage position in any suitable manner. For example, a frangible seal may be arranged in the liquid path between the liquid reservoir and the heating element to prevent liquid held in the liquid reservoir from passing through the liquid path to the heating element when the first part and the second part are in the storage position, and the frangible seal may be ruptured to enable liquid to pass from the liquid reservoir through the liquid path to the heating element when the second part is moved relative to the first part from the storage position to the use position. In some preferred embodiments, the second part comprises a stop cooperating with the first part to prevent liquid in the liquid reservoir from passing through the liquid path to the heating element when the first part and the second part are in the storage position, and the stop moves with the second part relative to the first part to a position in which liquid held in the liquid reservoir is able to pass through the liquid path to the heating element when the second part is moved from the storage position to the use position. Such an arrangement comprising a movable stopper enables the cartridge to be repeatedly moved between the use position and the storage position and to continue to prevent liquid held in the liquid reservoir from passing through the liquid path to the heating element when the first and second parts are in the storage position, as the stopper is not ruptured during movement between the storage position and the use position.

The first part and the second part may be configured to be biased to the storage position. For example, a resilient element (such as a spring) may be provided in the cartridge to urge the second part from the use position to the storage position relative to the first part. Advantageously, biasing the first part and the second part to the storage position instead of the use position may reduce the likelihood of leakage of liquid held in the liquid reservoir when the cartridge is not received in the device cavity.

The first and second parts of the cartridge may be movable in any suitable manner between a storage position and a use position. In some preferred embodiments, the second part is slidable relative to the first part.

In some particularly preferred embodiments, the cartridge housing includes a first piece and a second piece. In these embodiments, the first part is a first cartridge housing part and the second part is a second cartridge housing part.

In some embodiments, and in particular in some embodiments in which the cartridge comprises a first part and a second part movable relative to the first part, the device comprises a pushing element. The pushing element may be configured to move the first part relative to the second part or to move the second part relative to the first part when a portion of the cartridge is received in the device cavity. The pushing element may be configured to move the first part and the second part from the storage position to the use position when a portion of the cartridge is received in the device cavity. The pushing element may be configured to engage with the first part when a portion of the cartridge is received in the device cavity. The pushing element may be configured to contact the first part when a portion of the cartridge is received in the device cavity. The pushing element may be configured to contact the second part when a portion of the cartridge is received in the device cavity.

Advantageously, providing the device with a pushing element configured to move the first part and the second part from the storage position to the use position when a portion of the cartridge is received in the device cavity may help reduce the likelihood of leakage of liquid held in the liquid reservoir when the cartridge is not received in the device cavity and minimize any additional actions that a user needs to perform in order to prepare the aerosol-generating system for use. By enabling the cartridge to be moved from the storage position to the use position during insertion of a portion of the cartridge into the device cavity, providing the device with a pushing element minimizes the additional actions that the user needs to perform in order to prepare the aerosol-generating system for use.

In some embodiments, the device housing includes a pushing element.

The pushing element may extend into the device cavity. In some preferred embodiments, the pushing element extends from the substantially closed end of the device cavity into the device cavity.

In some preferred embodiments, at least a portion of the surface of the pushing element defines at least a portion of the surface of the airflow chamber when a portion of the cartridge is received in the device chamber.

In some embodiments including a pressure sensor cavity, the pressure sensor cavity is at least partially disposed in the pushing element. In these embodiments, at least a portion of the pressure sensor may be disposed in the pushing element.

In some embodiments including an additional airflow path between the airflow cavity and the pressure sensor cavity, at least a portion of the additional airflow path may be disposed in the pushing element.

In some embodiments, the sealing element is disposed at the substantially closed end of the device cavity. The sealing element may be arranged to substantially not obstruct the airflow path. The sealing element may substantially cover the substantially closed end of the device cavity without blocking the airflow path. Advantageously, the sealing element may help ensure that air flows through the airflow path without escaping through other gaps or spaces in the device housing. Particularly advantageously, in case a flow restriction is provided in the air flow path, the sealing element may help to ensure that air flows through the flow restriction, but not through other gaps or spaces in the device housing. The sealing element may be an elastic element. The sealing element may be an elastomeric element. The sealing element may provide a liquid-tight seal, or preferably a gas-tight seal, over a portion of the gas flow path. Providing an airtight seal (which may be referred to as an airtight seal) may ensure that the airflow through the portion of the airflow path that includes the sealing element is tightly controlled, thereby creating a predictable and consistent suction resistance through the airflow path. In some embodiments, the sealing element may be disposed at the flow restriction.

The apparatus may further comprise a controller. The controller may be configured to receive pressure measurements from the pressure sensor. The controller may be configured to receive pressure measurement information from the pressure sensor. The pressure measurement may include pressure measurement information. The pressure measurement information may include any information available from the pressure sensor. The pressure measurement information includes information about the pressure at the airflow chamber.

The controller may be configured to determine when a user is drawing on the aerosol-generating system based on pressure measurements from the pressure sensor. The controller may be configured to determine when a user is drawing on the aerosol-generating system based on pressure measurement information received from the pressure sensor.

The controller may be configured to receive pressure measurements at regular intervals. The controller may be configured to receive pressure measurement information from the pressure sensor at regular intervals. The controller may be configured to regularly receive pressure measurement information from the pressure sensor. The controller may be configured to continuously receive pressure measurement information from the pressure sensor. The controller may be configured to receive pressure measurements at any suitable sampling rate. The controller may be configured to receive the pressure measurements and pressure measurement information at any suitable sampling rate. For example, the controller may be configured to receive pressure measurements and pressure measurement information at a sampling rate of at least 50 hertz, at least 60 hertz, at least 65 hertz. In some preferred embodiments, the controller is configured to receive the pressure measurements and pressure measurement information at a sampling rate of about 75 hertz.

The controller may be configured to determine the average pressure from pressure measurement information received from the pressure sensor over time. The average pressure may be a moving average. In other words, the average pressure may be updated for each subsequent measurement of pressure. The moving average pressure may be a mean pressure, a median pressure, or a mode pressure. The moving average pressure may be determined from a plurality of pressure measurements received from the pressure sensor. The moving average pressure may be determined from a plurality of consecutive pressure measurements received from the pressure sensor. The moving average pressure may be determined from any suitable number of pressure measurements. For example, the moving average may be determined from at least two, three, four, five, six, seven, eight, nine, or ten pressure measurements. The moving average pressure may be determined from 2 to 100 pressure measurements, 2 to 75 pressure measurements, or 2 to 40 pressure measurements.

Determining a moving average pressure from a plurality of pressure measurements taken over time may provide a reference pressure to the controller with which subsequent pressure measurements may be compared. Comparing the subsequent pressure measurements to the determined average pressure measurement may enable the controller to determine a greater than expected change in the measured pressure. A greater than expected change in pressure in the airflow chamber may indicate that a user is drawing on the aerosol-generating system.

The controller may be configured to determine when a user is drawing on the aerosol-generating system based on pressure measurement information received from the pressure sensor. The controller may be configured to detect a puff on the aerosol-generating system based on pressure measurement information received from the pressure sensor. The controller may be configured to determine when a user is drawing on the aerosol-generating system based on a comparison of pressure measurement information received from the pressure sensor to a threshold value. The controller may be configured to determine when a user is drawing on the aerosol-generating system based on a comparison of pressure measurement information received from the pressure sensor with a moving average pressure determined from earlier pressure measurement information received from the pressure sensor.

In some preferred embodiments, the controller may be configured to determine a moving average pressure from pressure measurement information received from the pressure sensor over time, compare subsequent pressure measurements to the determined moving average pressure, and determine when a user is drawing on the aerosol-generating system based on the comparison. When a puff is detected, the moving average may remain constant or not updated until it is determined that the user has stopped making puffs on the aerosol-generating system. Maintaining the moving average pressure constant as the user draws on the aerosol-generating system may enable the moving average pressure to be used as a reference pressure with which pressure measurements taken during the drawing may be compared. Maintaining the moving average pressure constant during aspiration may enable the end of aspiration to be determined.

Advantageously, determining when a user is drawing on the aerosol-generating system based on the moving average pressure compared to a comparison of the pressure measurement to a static threshold, and comparing subsequent pressure measurements to the moving average pressure may reduce the likelihood of false determinations of drawing caused by changes in atmospheric pressure (such as changes in altitude). This is because the determined moving average can vary with a gradual change in the external pressure. In particular, when a single pressure sensor is provided that senses absolute pressure in the airflow chamber, it is advantageous to compare the pressure measurement to a determined moving average pressure rather than a static threshold. In the case where a gauge pressure sensor, a differential pressure sensor, or two or more pressure sensors are provided and differential pressure is measured or determined, there is less benefit in comparing the differential pressure measurement or differential pressure to a determined moving average rather than a static threshold. This is because the differential pressure measurement or differential pressure is less affected by changes in external pressure or atmospheric pressure than absolute pressure measurement alone.

The controller may be configured to determine an end of a puff on the aerosol-generating system based on pressure measurement information received from the pressure sensor. The controller may be configured to determine when the user stops drawing on the aerosol-generating system based on pressure measurement information received from the pressure sensor. The controller may be configured to determine when the user stops drawing on the aerosol-generating system based on a comparison of pressure measurement information received from the pressure sensor to a threshold value. The controller may be configured to determine a moving average pressure from pressure measurement information received from the pressure sensor over time, compare subsequent pressure measurements to the determined moving average pressure, determine when a user is drawing on the aerosol-generating system based on the comparison, and determine when a user is ceasing to draw on the aerosol-generating system based on a comparison of additional subsequent pressure measurements to a previously determined moving average. In other words, the determined moving average pressure for comparison with subsequent pressure measurements when a puff is detected may be stored by the controller and may be used as a reference value or threshold with which additional subsequent pressure measurements are compared to determine when the user stops making puffs on the aerosol-generating system.

The controller may be configured to determine the aspiration duration based on pressure measurement information received from the pressure sensor. The controller may be configured to determine the puff duration based on a difference between a first determination that the user is engaged in a puff on the aerosol-generating system and a subsequent determination that the user has stopped engaged in a puff on the aerosol-generating system.

Typical aspiration durations may range between about 1 second and about eight seconds, and more typically between about 3 seconds and about six seconds.

The cartridge includes a heating element. The heating element is configured to heat a liquid aerosol-forming substrate held in the liquid reservoir to generate an aerosol.

Where the apparatus comprises a controller, the controller may be configured to control the supply of electrical power to the heating element. The controller may be configured to control the supply of power to the heating element based on the pressure measurement received from the pressure sensor. In some embodiments, in which the controller is configured to determine when a user is drawing on the aerosol-generating system based on pressure measurements received from the pressure sensor, the controller may be configured to control the supply of power to the heating element based on when it is detected that the user is drawing on the aerosol-generating system.

In some embodiments, the heating element comprises a resistive heating element.

The resistive heating element may be formed of any suitable material.

The resistive heating element may be formed of an electrically conductive material. As used herein, "electrically conductive" refers to a material having a volume resistivity of less than about 1x10 ^-5 ohm-meters (Ω -m), typically between about 1x10 ^-5 ohm-meters (Ω -m) and about 1x10 ^-9 ohm-meters (Ω -m) at 20 degrees celsius (°).

The resistive heating element may be formed of a thermally conductive material. As used herein, "thermally conductive" refers to a material having a bulk thermal conductivity of at least about 10 watts/meter kelvin (mW/(m k)) at 23 degrees celsius (°c) and 50% relative humidity as measured using the Modified Transient Planar Source (MTPS) method.

The resistive heating element may be formed from at least one of graphite, molybdenum, silicon carbide, metal, stainless steel, niobium, aluminum, nickel, titanium, and composites of metallic materials.

In some preferred embodiments, the heating element comprises a susceptor element.

As used herein, "susceptor element" refers to an element that is heatable by penetration of a varying magnetic field. The susceptor element is typically heatable by at least one of joule heating and hysteresis loss generated by inducing eddy currents in the susceptor element.

In case the heating element comprises a susceptor element, the aerosol-generating system comprises an induction heating assembly comprising an inductor coil and the heating element. The device comprises an inductor coil and the cartridge comprises a susceptor element.

Where the apparatus comprises an inductor coil, the apparatus may be configured to supply a varying current to the inductor coil. When the inductor coil is supplied with a varying current, the inductor coil is configured to generate a varying magnetic field. When a portion of the cartridge is received in the device cavity, the inductor coil and the susceptor element are arranged such that a varying magnetic field generated by the inductor coil when supplied with a varying current penetrates the susceptor element.

The inductor coil may be arranged at any suitable location. The inductor coil may be arranged to generate a varying magnetic field in the device cavity. The inductor coil may be located in or around the device cavity. The inductor coil may define a device cavity.

As used herein, "varying current" refers to a current that varies over time. When a varying current is supplied to the inductor coil, the inductor coil generates a varying magnetic field. The term "varying current" is intended to include alternating current. In case the varying current is an alternating current, the alternating current supplied to the inductor coil generates an alternating magnetic field.

The varying current may be an alternating current. As used herein, "alternating current" refers to a current that periodically changes direction. The alternating current may have any suitable frequency. Suitable frequencies of the alternating current may be between 100 kilohertz (kHz) and 30 megahertz (MHz). In case the at least one inductor coil is a tubular inductor coil, the alternating current may have a frequency between 500 kilohertz (kHz) and 30 megahertz (MHz). In the case where the at least one inductor coil is a flat coil, the alternating current may have a frequency between 100 kilohertz (kHz) and 1 megahertz (MHz).

The inductor coil may have any suitable form. The inductor coil may be a tubular inductor coil. The inductor coil may be a planar inductor coil. The inductor coil may be a flat inductor coil. Preferably, the inductor coil is a tubular coil defining a device lumen.

The inductor coil may have any suitable number of turns.

The inductor coil may be formed of any suitable material. The inductor coil may be formed of at least one of silver, gold, aluminum, brass, zinc, iron, nickel, and alloys thereof, as well as conductive ceramics such as yttrium doped zirconia, indium tin oxide, and yttrium doped titanates.

When a portion of the cartridge is received in the device cavity, the susceptor element of the cartridge may be arranged to be penetrated by a varying magnetic field generated by the inductor coil when a varying current is supplied to the inductor coil.

The susceptor element may be formed of any suitable material. Preferably, the susceptor element comprises a magnetic material heatable by penetration of a varying magnetic field. The magnetic material may be a ferromagnetic material such as ferrite, ferrite iron, a ferromagnetic alloy, a ferromagnetic steel, or a ferromagnetic stainless steel such as SAE 400 series stainless steel, SAE 409 type, 410 type, 420 type, or 430 type stainless steel.

As used herein, "magnetic material" refers to a material capable of interacting with a magnetic field, including both paramagnetic and ferromagnetic materials.

In some preferred embodiments, the susceptor element comprises at least about 5%, or at least about 20%, or at least about 50%, or at least about 90% by dry weight of ferromagnetic or paramagnetic material.

The susceptor element shape may be different from the inductor coil shape. Preferably, the susceptor element is substantially the same shape as the inductor coil.

The inductor coil size may be different from the inductor coil size. Preferably, the susceptor element is substantially the same size as the inductor coil.

In some preferred embodiments, the apparatus comprises a controller. The controller may be configured to control the supply of electrical power to the heating element. In case the aerosol-generating system comprises an induction heating arrangement and the device comprises an inductor coil of the induction heating arrangement, the controller may be configured to control the supply of power to the inductor coil.

The controller may be configured to continuously supply current to the heating element or the inductor coil after the aerosol-generating system is activated. The controller may be configured to intermittently (such as on a port-by-port suction basis) supply current to the heating element or the inductor coil.

The controller may include a microprocessor, which may be a programmable microprocessor, a microcontroller, or an Application Specific Integrated Chip (ASIC) or other electronic circuitry capable of providing control.

The controller may be part of the control circuitry of the device. The control circuitry may include additional electronic components. The control circuitry may advantageously include a DC/AC inverter, which may include a class D or class E power amplifier.

The apparatus may further comprise a power source. The power source may be configured to supply power to the heating element. The controller may be configured to control the supply of electrical power from the power source to the heating element. Where the aerosol-generating system comprises an induction heating arrangement, the power supply may be configured to supply power to an inductor coil of the induction heating arrangement. The controller may be configured to control the supply of electrical power from the power source to the inductor coil.

The power source may be a DC power source. The power source may include at least one of a battery and a capacitor. The power source may be a battery. The battery may be any suitable type of battery. The battery may be a lithium-based battery, such as a lithium cobalt battery, a lithium iron phosphate battery, a lithium titanate battery, or a lithium polymer battery. The battery may be a nickel metal hydride battery or a nickel cadmium battery. The power supply may be another form of charge storage device such as a capacitor. In one embodiment, the power source is a DC power source having a DC power voltage in the range of about 2.5 volts to about 4.5 volts and a DC power current in the range of about 1 amp to about 10 amps (corresponding to a DC power in the range of about 2.5 watts to about 45 watts).

In case the aerosol-generating system comprises an induction heating arrangement and the device comprises an inductor coil of the induction heating arrangement, the power supply and the controller may be configured to supply an alternating current to the inductor coil.

The power supply and controller may be configured to operate at a high frequency. In the case of an apparatus comprising an inductor coil of an induction heating arrangement, the power supply and the controller may be configured to supply a high frequency oscillating current to the inductor coil. As used herein, the term "high frequency oscillating current" refers to an oscillating current having a frequency between about 500 kilohertz and about 30 megahertz. The frequency of the high frequency oscillating current may be about 1 megahertz to about 30 megahertz, preferably about 1 megahertz to about 10 megahertz, and more preferably about 5 megahertz to about 8 megahertz.

Where the controller is configured to control the supply of power to the heating element or to the inductor coil of the induction heating arrangement, the controller may be configured to control the supply of power to the heating element in any suitable manner. Preferably, the controller is configured to control the supply of power to the heating element in a pulsed manner. In the case where the controller is configured to control the supply of power to the heating element in a pulsed manner, the controller may be configured to control the supply of power to the heating element by pulse width modulation.

The controller may be configured to control the supply of power to the heating element based on the pressure measurement received from the pressure sensor.

The cartridge includes a liquid reservoir configured to hold a liquid aerosol-forming substrate. The liquid aerosol-forming substrate may comprise any suitable composition.

The liquid aerosol-forming substrate may comprise nicotine. The nicotine-containing liquid aerosol-forming substrate may be a nicotine salt substrate. The liquid aerosol-forming substrate may comprise a plant-based material. The liquid aerosol-forming substrate may comprise tobacco. The liquid aerosol-forming substrate may comprise a tobacco-containing material comprising a volatile tobacco flavour compound which is released from the aerosol-forming substrate upon heating. The liquid aerosol-forming substrate may comprise homogenized tobacco material. The liquid aerosol-forming substrate may comprise a tobacco-free material. The liquid aerosol-forming substrate may comprise a homogenized plant based material.

The liquid aerosol-forming substrate may comprise one or more aerosol-formers. The aerosol former is any suitable known compound or mixture of compounds that, in use, promotes the formation of a dense and stable aerosol and is substantially resistant to thermal degradation at the operating temperature of the system. Examples of suitable aerosol formers include propylene glycol and propylene glycol. Suitable aerosol formers are well known in the art and include, but are not limited to, polyols such as triethylene glycol, 1, 3-butanediol, and glycerol, esters of polyols such as mono-, di-, or triacetin, and aliphatic esters of monocarboxylic, dicarboxylic, or polycarboxylic acids such as dimethyl dodecanedioate and dimethyl tetradecanedioate. The liquid aerosol-forming substrate may comprise water, solvents, ethanol, plant extracts and natural or artificial fragrances. The liquid aerosol-forming substrate may comprise nicotine and at least one aerosol-forming agent. The aerosol former may be glycerol or propylene glycol. The aerosol former may include both glycerol and propylene glycol. The liquid aerosol-forming substrate may have a nicotine concentration of between about 0.5% and about 10%, for example about 2%.

The aerosol-generating system may be a handheld aerosol-generating system. The aerosol-generating system may be a handheld aerosol-generating system configured to allow a user to draw on the mouth end to draw aerosol through the air outlet. The aerosol-generating system may be of a size comparable to a conventional cigar or cigarette. The aerosol-generating system may have an overall length of between about 25mm and about 150 mm. The aerosol-generating system may have an outer width or diameter of between about 5mm and about 30 mm.

The invention is defined in the claims. However, a non-exhaustive list of non-limiting examples is provided below. Any one or more features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

1. An aerosol-generating system, comprising:

a cartridge, the cartridge comprising:

A cartridge housing;

A liquid reservoir configured to hold a liquid aerosol-forming substrate, and

A heating element configured to heat liquid from the liquid reservoir, and

An apparatus, the apparatus comprising:

A device housing defining a device cavity configured to receive a portion of the cartridge;

Wherein:

When the portion of the cartridge is received in the device cavity, the aerosol-generating system comprises an airflow path defined between an air inlet and an air outlet;

an airflow cavity is located in the airflow path when the portion of the cartridge is received in the device cavity, the airflow cavity being defined between the cartridge housing and the device housing, and

The device comprises a pressure sensor arranged to detect the pressure in the airflow chamber.

2. An aerosol-generating system according to example 1, wherein when air is drawn through the airflow path between the air inlet and the air outlet, the pressure in the airflow path has a minimum value in the airflow chamber.

3. An aerosol-generating system according to example 1 or example 2, wherein a flow restriction is arranged in the airflow path between the air inlet and the airflow chamber.

4. An aerosol-generating system according to example 3, wherein the flow restriction is arranged immediately upstream of the airflow chamber.

5. An aerosol-generating system according to example 3 or example 4, wherein the flow restriction is a portion of the airflow path having a width that is less than a width of the airflow cavity.

6. An aerosol-generating system according to any of examples 3 to 5, wherein the flow restriction is a portion of the airflow path having a width that is smallest in any portion of the airflow path.

7. An aerosol-generating system according to any of examples 3 to 6, wherein the flow restriction is a portion of the airflow path having a cross-sectional area that is smaller than a cross-sectional area of the airflow chamber.

8. An aerosol-generating system according to any of examples 3 to 7, wherein the flow restriction is a portion of the airflow path having a smallest cross-sectional area in any portion of the airflow path.

9. An aerosol-generating system according to any of examples 3 to 8, wherein the aerosol-generating device comprises the flow restriction.

10. An aerosol-generating system according to any of examples 3 to 8, wherein the flow restriction is defined between the cartridge housing and the device housing when the portion of the cartridge is received in the device cavity.

11. An aerosol-generating system according to example 10, wherein at least a portion of the surface of the cartridge housing defines at least a portion of the surface of the flow restriction.

12. An aerosol-generating system according to example 10 or example 11, wherein at least a portion of a surface of the device housing defines at least a portion of a surface of the flow restriction.

13. An aerosol-generating system according to any of examples 3 to 12, wherein the flow restriction has a width of between 0.15mm and 0.8 mm.

14. An aerosol-generating system according to any of examples 3 to 13, wherein the flow restriction has a depth of between 0.3 mm and 1.2 mm.

15. An aerosol-generating system according to any of examples 3 to 14, wherein the flow restriction has a length of between 1 and 2mm.

16. An aerosol-generating system according to any of examples 3 to 14, wherein the flow restriction has a cross-sectional area of between 0.045 square millimeters and 1 square millimeter.

17. An aerosol-generating system according to any of examples 1 to 16, wherein at least a portion of the surface of the cartridge housing defines at least a portion of the surface of the airflow chamber.

18. An aerosol-generating system according to any of examples 1 to 17, wherein at least a portion of a surface of the device housing defines at least a portion of a surface of the airflow chamber.

19. An aerosol-generating system according to any of examples 1 to 18, wherein the air inlet of the airflow path is defined between the cartridge and the device when a portion of the cartridge is received in the device cavity.

20. An aerosol-generating system according to any of examples 1 to 19, wherein the cartridge comprises:

Mouth end, and

A connection end opposite the mouth end, wherein the connection end is configured to be received by the device lumen.

21. An aerosol-generating system according to example 20, wherein the air outlet of the airflow path is arranged at the mouth end of the cartridge.

22. An aerosol-generating system according to example 20 or example 21, wherein the mouth end of the cartridge is configured for inhalation by a user on the mouth end to inhale an aerosol generated by the aerosol-generating system.

23. An aerosol-generating system according to any of examples 1 to 22, wherein the pressure sensor is located in a pressure sensor cavity in the device.

24. The aerosol-generating system of example 23, wherein an additional airflow path is disposed between the airflow chamber and the suction sensor chamber to enable air to flow between the airflow chamber and the suction sensor chamber.

25. An aerosol-generating system according to any of examples 1 to 24, wherein the device cavity comprises:

an open end enabling the portion of the cartridge to be received in the device cavity, and

A substantially closed end opposite the open end.

26. An aerosol-generating system according to example 25, wherein the device cavity interfaces with the airflow path at the substantially closed end.

27. An aerosol-generating system according to example 25 or example 26, wherein the flow restriction is disposed at or around a substantially closed end of the device cavity.

28. An aerosol-generating system according to any of examples 25 to 27, wherein a sealing element is arranged at the substantially closed end of the device cavity, and wherein the sealing element does not substantially obstruct the airflow path.

29. An aerosol-generating system according to any of examples 25 to 28, wherein the device housing comprises a pushing element, and wherein the pushing element extends from the substantially closed end into the device cavity.

30. An aerosol-generating system according to example 29, wherein the cartridge housing comprises two parts, a first cartridge housing part, and a second cartridge housing part, wherein the second cartridge housing part is movable relative to the first cartridge housing part, and wherein the pushing element is arranged to contact the second cartridge housing part and move the second cartridge housing part relative to the first cartridge housing part when the portion of the cartridge is received in the device cavity.

31. An aerosol-generating system according to example 29 or example 30, wherein at least a portion of a surface of the pushing element defines at least a portion of a surface of the airflow chamber when the portion of the cartridge is received in the device chamber.

32. An aerosol-generating system according to any of examples 1 to 31, wherein the aerosol-generating system further comprises an induction heating assembly comprising an inductor coil and the heating element, wherein the device comprises the inductor coil, and wherein the heating element comprises a susceptor element.

33. An aerosol-generating system according to example 32, wherein the device is configured to supply a varying current to the inductor coil, wherein the inductor coil is configured to generate an alternating magnetic field when supplied with the varying current, and wherein the inductor coil and susceptor element are arranged such that the varying magnetic field penetrates the susceptor element when the portion of the cartridge is received in the device cavity.

34. The aerosol-generating system of example 32 or example 33, wherein the inductor coil defines the device cavity.

35. An aerosol-generating system according to any of examples 1 to 34, wherein the device further comprises a power source configured to supply power to the heating element when a portion of the cartridge is received in the device cavity.

36. An aerosol-generating system according to any of examples 32 to 34, wherein the device further comprises a power source and a controller configured to supply a varying current to the inductor coil.

The invention will be further described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 shows a schematic view of a cartridge of an aerosol-generating system according to an embodiment of the disclosure;

fig. 2 shows a schematic view of a device of an aerosol-generating system according to an embodiment of the disclosure;

Fig. 3 shows a schematic view of an aerosol-generating system comprising the cartridge of fig. 1 and the device of fig. 2, according to an embodiment of the disclosure;

fig. 4 shows a portion of the aerosol-generating system of fig. 3, wherein the cartridge is not received in a device cavity of the device;

Fig. 5 shows a portion of the aerosol-generating system of fig. 3, wherein the cartridge is received in a device cavity of the device;

Fig. 6 shows a portion of the aerosol-generating system of fig. 3, wherein the cartridge is received in the device cavity;

fig. 7 shows a cross-sectional view of the aerosol-generating system of fig. 6;

Fig. 8 shows a portion of the aerosol-generating system of fig. 3, wherein the cartridge is received in a device cavity of a device and air is being drawn through the aerosol-generating system;

Fig. 9 shows a portion of an aerosol-generating system according to another embodiment of the present disclosure, in which a cartridge is received in a device cavity of a device, and

Fig. 10 shows a plan view of the device of the aerosol-generating system of fig. 9 from the open end towards the substantially closed end of the device cavity;

Fig. 11 shows a portion of an aerosol-generating system according to another embodiment of the disclosure, in which a cartridge is received in a device cavity of a device and air is being drawn through the aerosol-generating system, and

Fig. 12 shows a portion of the aerosol-generating system of fig. 11.

A first example of an aerosol-generating system 10 according to the present disclosure is shown in fig. 1-8. The aerosol-generating system 10 comprises a cartridge 12 and a device 14.

In fig. 1, a cartridge 12 is shown. The cartridge 12 includes a cartridge housing including a first cartridge housing part 16 and a second cartridge housing part 18. The second cartridge housing part 18 is substantially tubular, defining an internal passageway 19. The first cartridge housing part 16 is also substantially tubular, has a larger width than the second cartridge housing part 18, and defines an internal passageway having a larger width than the second cartridge housing part 18. The second cartridge housing piece 18 is received within the interior passageway of the first cartridge housing piece 16 such that the second cartridge housing piece 18 is surrounded by the first cartridge housing piece 16 with the longitudinal axis of the second housing piece 18 aligned with the longitudinal axis of the first cartridge housing piece 16. When the second cartridge housing piece 18 is received within the interior passageway of the first cartridge housing piece 16, the second cartridge housing piece 18 is movable relative to the first cartridge housing piece 16 between a storage position as shown in fig. 1 and a use position as shown in fig. 3. In this embodiment, the second cartridge housing piece 18 is slidable relative to the first cartridge housing piece 16 along aligned longitudinal axes of the first and second cartridge housing pieces 16, 18.

The cartridge 12 includes a mouth end 20 and a connection end 21. At the mouth end of the first cartridge housing part 16, the first cartridge housing part 16 includes an air outlet 22 having a width slightly less than the width of the internal passageway 19 of the second cartridge housing part 18. An inner tube 23 extends from the air outlet 22 of the first cartridge housing piece 16 along the longitudinal axis of the first cartridge housing piece 16. The second cartridge housing part 18 is received over the inner tube 23 of the first cartridge housing part 16 at the mouth end 20. The internal passageway 19 of the second cartridge housing part 18 is slidable over the inner tube 23 along the aligned longitudinal axes of the first and second cartridge housing parts 16, 18 to move the second cartridge housing part 18 between the storage position and the use position. An O-ring 24 is provided between the inner tube 23 of the first cartridge housing part and the second cartridge housing part 18 to prevent liquid flow through the gap between the inner tube 29 and the second cartridge housing part 18. Further, at the mouth end of the first cartridge housing part 16, the first cartridge housing part 16 has a region with a wider outer diameter than the connection end of the first cartridge housing part 16.

A liquid reservoir 25 is defined in the region between the region of the first cartridge housing part 16 having the wider diameter and the second cartridge housing part 18 at the mouth end of the cartridge 12. The liquid reservoir 25 is configured to hold a liquid aerosol-forming substrate 26. The flow of liquid aerosol-forming substrate 26 from the liquid reservoir 25 into the internal passageway 19 of the second cartridge housing part 18 is prevented at the mouth end by the O-ring 24. The second cartridge housing part 18 further comprises an annular first stop 27 extending radially outwardly from the second cartridge housing part 18 at a distance from the mouth end of the second cartridge housing part 18 of about the length of the inner tube 23 of the first cartridge housing part 16. The first stop 27 extends radially outwardly from the second cartridge housing part a distance to contact the inner surface of the internal passageway of the first cartridge housing part 16 below the wider area at the mouth end. When the cartridge 12 is in the storage position, the first stop 27 of the second cartridge housing part 18 contacts the inner surface of the first cartridge housing part 16 and prevents the liquid aerosol-forming substrate 26 from flowing out of the liquid reservoir 25 beyond the first stop 27 to the connecting end 21 of the cartridge 12.

As shown in fig. 3, when the cartridge is moved to the use position, the second cartridge housing part 18 slides along the aligned longitudinal axis toward the mouth end of the first cartridge housing part 16 until the first stop 27 reaches a wider area at the mouth end of the second cartridge housing part 18. When the first stop 27 reaches a wider area at the mouth end of the second cartridge housing part 18, the first stop 27 no longer contacts the inner surface of the first cartridge housing part 16 and a gap is provided between the first cartridge housing part 16 and the second cartridge housing part 18 such that the liquid aerosol-forming substrate 26 in the liquid reservoir 25 can flow out of the liquid reservoir 25 into the gap between the first cartridge housing part 16 and the second cartridge housing part 18 at the connection end of the second cartridge housing part 18.

A second stop 28 is provided at the connecting end of the second cartridge housing part 18. The second stop 28 is substantially similar to the first stop 27 and contacts the inner surface of the internal passageway of the first cartridge housing part 16 below the wider area at the mouth end to prevent liquid flow beyond the connecting end of the second cartridge housing part 18 when the cartridge 12 is in the use position. An additional O-ring seal 29 is also provided at the second stop 28 to improve the seal between the second stop 28 and the inner surface of the internal passageway of the first cartridge housing part 16.

The cartridge 12 also includes a heater assembly 30. The heater assembly 30 is generally in the form of a flat planar sheet. The heater assembly 20 comprises a heating element 31 in the form of a susceptor element, and a wicking element 32. In this embodiment, the susceptor element 31 comprises a sintered mesh formed by ferritic stainless steel wires and austenitic stainless steel wires. The wicking element 32 comprises a porous body of rayon.

The heater assembly 30 is held in the second cartridge housing section 18 toward the connection end and below the first stop 27. The susceptor element 31 is arranged to extend across the internal passage 19 of the second cartridge housing part 18, and the wicking element 32 is arranged to extend outwardly beyond the susceptor element 31 at opposite sides of the susceptor element 31 and radially outwardly through the second cartridge housing part 18 at each side at a distance slightly less than the first and second stops 27, 28.

As shown in fig. 3, when the cartridge 12 is in the use position and the liquid aerosol-forming substrate 26 from the liquid reservoir 25 flows into the gap between the first cartridge housing part 16 and the second cartridge housing part 18 at the connection end, the liquid aerosol-forming substrate 26 in the gap is in contact with and is drawn by the wicking element onto the susceptor element 31.

At the connection end 21 of the cartridge, the second cartridge housing section 18 includes a base 33 that substantially closes the connection end of the second cartridge housing section 18, and the first cartridge housing section 16 includes an inwardly extending flange 34 that extends to the base 33 of the second cartridge housing section 18, but does not extend above the base 33. In other words, the inwardly extending flange 34 leaves an opening 35 at the connecting end of the first cartridge housing section 16. The second cartridge housing portion 18 further includes an opening 36 immediately above the base 33 at the connection end around the outer periphery of the second cartridge housing portion 18. The openings 36 in the second cartridge housing section 18 and the openings 35 in the first cartridge housing section 16 enable air to be drawn into the interior passageway 19 of the second cartridge housing section 18 and out of the interior passageway 19 through the inner tube 23 and the air outlet 22 of the first cartridge housing section 16.

In fig. 2, a device 14 is shown. The device 14 includes a device housing 38 defining a device cavity 40 at a connection end 41 of the device 14. The device cavity 40 is configured to receive the connection end 21 of the cartridge 12. The device lumen 40 includes an open end at the connection end 41 of the device 14 and a substantially closed end opposite the open end.

The device 14 also includes an inductor coil 42. The inductor coil 42 defines a portion of the device cavity 40. The inductor coil 42 is made of copper wire having a circular cross section and is arranged on a coil former element (not shown). In this embodiment, the inductor coil 42 is a helical coil and has a circular cross-section when viewed parallel to the longitudinal axis of the device 14.

As shown in fig. 3, when the connection end 21 of the cartridge 12 is received in the device cavity 40 of the device 14, the inductor coil 42 is aligned with the heater assembly 30 of the cartridge such that the inductor coil 42 is aligned with the susceptor element 32. The susceptor element 32 and the inductor coil 42 together form an induction heating assembly 43.

The device 14 further comprises a controller 44 and a power supply 45, which also form part of the induction heating assembly 43. The power source 45 comprises a rechargeable lithium ion battery that is rechargeable via an electrical connector (not shown) at a distal end of the device 14 opposite the connection end 41. The controller 44 is connected to the power source 45 and to the inductor coil 42 such that the controller 44 is able to control the supply of power from the power source 45 to the inductor coil 42. The controller 44 and the power supply 45 are configured to supply an alternating current to the inductor coil 42.

When an alternating current is supplied to the inductor coil 42, the inductor coil 42 generates an alternating magnetic field in the device cavity 40. When the connection end 21 of the cartridge 12 is received in the device cavity 40, an alternating magnetic field generated by the inductor coil 42 is generated in the region of the susceptor element 32 aligned with the inductor coil 42. The inductor coil 42 has a similar length as the susceptor element 32 such that the alternating magnetic field generated by the inductor coil 42 penetrates the length of the susceptor element 32.

The device 14 further comprises a flux concentrator 46 partially surrounding the inductor coil 42 and configured to attenuate the alternating magnetic field generated by the inductor coil 42 in a direction radially outward from the device. This may reduce interference between the alternating magnetic field and other nearby electronics and reduce the risk of the alternating magnetic field inductively heating nearby objects outside the aerosol-generating system.

The device 14 further comprises a pushing element 47 extending from the substantially closed end into the device cavity 40 in the direction of the longitudinal axis of the device. The pushing element 47 has a cross section perpendicular to the longitudinal axis of the device that has a similar size and shape as the opening 35 at the connecting end of the first cartridge housing part 16. Thus, when the connection end 21 of the cartridge 12 is received in the device cavity 40, the push element 47 extends through the opening 35 at the connection end of the first cartridge housing part 16 and contacts the base 33 of the second cartridge housing part 18.

As shown in fig. 3, 4 and 5, when the connecting end 21 of the cartridge 12 is received in the device cavity 40, the pushing element 47 pushes the base 33 of the second cartridge housing part 18 relative to the first cartridge housing part 16 towards the mouth end of the first cartridge housing part 16 from the storage position to the use position. The length of the push element 47 is slightly greater than the distance required to move the second cartridge housing part 18 from the storage position to the use position so that when the connecting end 21 of the cartridge 12 is received in the device cavity 40, the cartridge is moved completely from the storage position to the use position.

As also shown in fig. 3, when the connection end 21 of the cartridge 12 is received in the device cavity 40, an air inlet 48 and an air gap 49 are defined between the first cartridge housing part 18 and the device housing 38 to enable ambient air to be drawn into the aerosol-generating system 10. The air gap 49 extends the length of the connecting end 21 of the cartridge 21 and the length of the device cavity 40 and extends between the inwardly extending flange 34 of the first cartridge housing part 16 and the substantially closed base of the device cavity 40. A flow restriction 50 is defined between the inwardly extending flange 34 and the pushing element 47. The flow restriction 50 will be described in more detail later with reference to fig. 4-7.

As also shown in fig. 3, when the connecting end 21 of the cartridge 12 is received in the device cavity 40, an airflow cavity 51 is defined between the inner surface of the first cartridge housing part 16 and the pushing element 47. The airflow chamber 51 is defined by the inwardly extending flange 34 of the first cartridge housing part 16 and the second stop 28 of the second cartridge housing part 18. Thus, the surface of the airflow chamber is defined in part by the surface of the housing 38 of the device 14 (i.e., the surface of the pushing element 47) and in part by the surface of the housing of the cartridge 12 (i.e., the surfaces of the first cartridge housing part 16 and the second cartridge housing part 18).

When the connecting end 21 of the cartridge 12 is received in the device cavity 40, an airflow path through the aerosol-generating system 10 is defined. The airflow path includes the air inlet 48, the air gap 49, the flow restriction 50, the airflow chamber 51, the opening 36 around the outer periphery of the second cartridge housing piece 18, the internal passageway 19 of the second cartridge housing piece 18, the inner tube 23 of the first cartridge housing piece 16, and the air outlet 22 of the first cartridge housing piece 16. In use, a user may draw on the mouth end 20 of the cartridge 12 and draw ambient air into the aerosol-generating system 10 at the air inlet 48, through the airflow path, and out of the aerosol-generating system 10 at the air outlet 22 for inhalation. Ambient air enters the aerosol-generating system 10 at an air inlet 48 between the cartridge housing and the device housing 38, through an air gap 49 to a flow restriction 50. Air enters the airflow chamber 51 through the flow restriction 50 and exits the airflow chamber 51 through the opening 36 into the interior passage 19 of the second cartridge housing piece 18. The air in the internal passage 19 flows past the susceptor element 31, through the inner tube 23, and exits the aerosol-generating system at the air outlet 22. The airflow through a portion of the aerosol-generating system is shown by the dashed arrow in fig. 8.

The device 14 further comprises a pressure sensor 52 arranged to sense the pressure in the airflow chamber 51. The pressure sensor 52 is arranged in a pressure sensor cavity 53 arranged partly in the pushing element 47. An additional air flow path 54 through the pushing element 47 is provided between the pressure sensor chamber 53 and the air flow chamber 51, so that the pressure sensor 52 arranged in the pressure sensor chamber 53 is able to sense the pressure in the air flow chamber 51.

The pressure sensor 52 is connected to the controller 44. Controller 44 receives pressure measurements from pressure sensor 52. The controller 44 is configured to determine whether a user is drawing on the aerosol-generating system based on the pressure measurements received from the pressure sensor 52.

When a user draws on the aerosol-generating system by drawing on the mouthpiece, the flow restriction 50 in the airflow path causes a significant pressure drop in the airflow cavity 51. Such a pressure drop makes suction detection more reliable and faster than if the flow restriction 50 were not present and therefore would not cause such a significant pressure drop in the airflow chamber 51 upon suction.

As shown in fig. 6 and 7, in this embodiment, a flow restriction 50 is defined between the housing 38 of the device 14 and the housing of the cartridge 12. The flow restriction 50 is defined by the surface of the inwardly extending flange 34 of the first cartridge housing part 16 and the surface of the pushing element 47, which is the surface of the housing 38 of the device 12. In this embodiment, the flow restriction 50 is formed by a "vertical" channel that extends in the length direction of the cartridge 12 and the device 14 between the radially innermost surface of the inwardly extending flange 34 of the first cartridge housing part 16 and the radially outer surface of the push element 47 of the device housing 38. The flow restriction 50 is the portion of the airflow path through the aerosol-generating system having the smallest cross-sectional area. The cross-sectional area of the flow restriction 50 may define a suction Resistance (RTD) through the flow restriction and the airflow path. Thus, the cross-sectional area of the flow restriction may be selected to provide a desired RTD through the airflow path. In this embodiment, the width 55 (which is shown in fig. 6) of the flow restriction 50 between the inwardly extending flange 34 and the pushing element 47 has a minimum dimension in any portion of the airflow path. In this embodiment, the flow restriction 50 is arranged immediately adjacent to the airflow chamber 51 so as to directly open into the airflow chamber 51.

In fig. 7 a cross section of the aerosol-generating system through line 56 of fig. 6 is shown, wherein the narrow flow restriction 50 is shown leading to the airflow chamber 51.

In addition, as shown in fig. 7, the cartridge 12 and the device 14 generally have a stadium-shaped cross-sectional shape. However, it should be appreciated that the cartridge and device may have other cross-sectional shapes (such as circular, elliptical, or polygonal) without changing the manner in which the aerosol-generating system operates.

In use, the connecting end 21 of the cartridge 12 is inserted into the device cavity 40 of the device 14. The pushing element 47 enters the cartridge 12 at the opening 35 and pushes the base 33 of the second cartridge housing part 18 such that the second cartridge housing part 18 moves towards the mouth end of the first cartridge housing part 16, thereby moving the cartridge from the storage position to the use position. When the connecting end 21 of the cartridge 12 is fully received in the device cavity 40, the liquid aerosol-forming substrate 26 held in the liquid reservoir 25 is able to flow from the liquid reservoir 25 to the heater assembly 30.

When a user draws on the mouth end 20 of the cartridge 12, air is drawn into the aerosol-generating system at the air inlet 48, through the air gap 49 and the flow restriction 50 into the airflow chamber 51. The pressure drop in the airflow chamber 51 caused by the user's puff is detected by the pressure sensor 52 in the pressure sensor chamber 53 and the controller 44 determines that a puff has been made on the aerosol-generating system 10 based on the pressure measurement received from the pressure sensor 52. Upon detection of the suction, the controller 44 causes an alternating current from the power supply 45 to be supplied to the inductor coil 42, which generates an alternating magnetic field in the device cavity 40. The susceptor element 31 of the cartridge 12 is penetrated by an alternating magnetic field and heated by joule heating generated by the eddy currents induced in the susceptor element and by hysteresis losses. The heated susceptor element 31 heats the liquid aerosol-forming substrate 26 at the susceptor element 31, which releases the volatile compounds into the internal passage 19 of the second cartridge housing 18 in the form of a vapor. As air from the airflow chamber 51 is drawn into the internal passageway through the opening 36 near the base 33 of the second cartridge housing piece, the vapor is entrained in the airflow through the internal passageway 19. The vapor cools as it is drawn into the inner tube 23 of the first cartridge housing part 16 along the internal passageway and condenses to form an aerosol. The aerosol is drawn out of the aerosol-generating system 10 at an air outlet 22 where it is inhaled by the user.

It should be appreciated that in other embodiments, the flow restrictions may be disposed in different locations in the airflow path. For example, the flow restriction can be defined by a substantially closed end surface of the device cavity and a surface at the connecting end of the inwardly extending flange of the first cartridge housing part. In these embodiments, the flow restriction may be spaced apart from the airflow chamber. In some embodiments, the flow restriction may be defined between both a surface of the inwardly extending flange of the first cartridge housing part and a surface of the pushing element of the device housing and between a substantially closed end surface of the device cavity and a surface of the inwardly extending flange of the first cartridge housing part at the connection end.

A portion of another example of an aerosol-generating system according to the present disclosure is shown in fig. 9 and 10. The example of fig. 9 and 10 is substantially the same as the aerosol-generating system of fig. 1-8, and like features are referred to with like reference numerals. The only difference between the aerosol-generating system 10 of fig. 9 and 10 and the aerosol-generating system 10 of fig. 1-8 is that in the aerosol-generating system 10 of fig. 9 and 10 the flow restriction 50 is arranged in a different position in the airflow path and the flow restriction 50 is arranged not immediately adjacent to the airflow chamber 51.

As shown in fig. 9 and 10, the flow restriction 50 is disposed in a portion of the airflow path defined by an open channel 57 in the substantially closed end of the device cavity 40 and a bottom surface at the connecting end of the inwardly extending flange 34 of the first cartridge housing part 16. In this embodiment, the flow restriction 50 is a "horizontal" channel formed between the surface of the open channel 57 at the substantially closed end of the device cavity 40 and the bottom surface of the inwardly extending flange 34 of the first cartridge housing part 16, extending in the width direction of the cartridge 12 and the device 14. Also in this embodiment, the flow restriction 50 is the portion of the airflow path through the aerosol-generating system 10 having the smallest cross-sectional area. The cross-sectional area of the flow restriction 50 may define a suction Resistance (RTD) through the flow restriction and the airflow path. Thus, the cross-sectional area of the flow restriction may be selected to provide a desired RTD through the airflow path. The width 55 and depth 58 of the flow restriction 50 determine the cross-sectional area of the flow restriction 50. In this embodiment, the depth 58 of the flow restriction 50 (which is shown in fig. 9) has a minimum dimension in any portion of the airflow path.

In the arrangement of the embodiment of fig. 9 and 10, the flow restriction 50 is spaced apart from the airflow chamber 51, wherein a further air gap 49 is provided between the flow restriction 50 and the airflow chamber 51. An additional air gap 49 is formed by the radially outer surface of the push element 47 of the device housing 38 and the radially innermost surface of the inwardly extending flange 34 of the second cartridge housing part 18.

In the arrangement of the embodiment of fig. 9 and 10, it may be necessary to seal the open end of the open channel 57 to form a flow restriction when the cartridge 12 is received in the device cavity 40 of the device 14. The seal may be a liquid tight seal, or preferably a gas tight seal. Providing an airtight seal (which may be referred to as an airtight seal) may ensure that the airflow through the flow restriction 50 is tightly controlled, resulting in predictable and consistent suction resistance through the airflow path. Such sealing may be accomplished by providing a sealing element (such as an elastomeric sheet) between the substantially closed end of the device cavity 40 and the bottom surface of the inwardly extending flange 34 of the first cartridge housing part 16. The sealing element may be disposed in the device 14 at the substantially closed end of the device cavity 40 or in the cartridge 12 on the bottom surface of the inwardly extending flange 34 of the first cartridge housing part 16.

It should be appreciated that in some embodiments, the flow restrictions may include both "horizontal" channels of the embodiments of fig. 1-8 and "vertical" channels of the embodiments of fig. 9 and 10. In other words, the flow restrictions may include both "vertical" channels extending in the length direction of the cartridge 12 and the device 14 between the radially innermost surface of the inwardly extending flange 34 of the first cartridge housing part 16 and the radially outer surface of the push element 47 of the device housing 38, and "horizontal" channels formed between the surface of the open channel 57 in the substantially closed end of the device cavity 40 and the bottom surface of the inwardly extending flange 34 of the first cartridge housing part 16, extending in the width direction of the cartridge 12 and the device 14.

A portion of another example of an aerosol-generating system according to the present disclosure is shown in fig. 11 and 12. The example of fig. 11 and 12 is substantially the same as the aerosol-generating system of fig. 1-8, and like features are referred to with like reference numerals. The only difference between the aerosol-generating system 10 of fig. 11 and 12 and the aerosol-generating system 10 of fig. 1-8 is that in the aerosol-generating system 10 of fig. 11 and 12, the device 14 comprises a flow restriction 50, and the flow restriction is arranged not immediately adjacent to the airflow chamber 51.

Providing a flow restriction 50 in the device 14 rather than between the cartridge 12 and the device 14 may make it easier to control the size of the flow restriction during use of the aerosol-generating system 10.

As shown in fig. 11 and 12, the flow restriction 50 is disposed in a passageway through a portion of the device housing 38 below the substantially closed end of the device cavity 40. Likewise, the flow restriction 50 is the portion of the airflow path through the aerosol-generating system 10 having the smallest cross-sectional area. The cross-sectional area of the flow restriction 50 may define a suction Resistance (RTD) through the flow restriction and the airflow path. Thus, the cross-sectional area of the flow restriction may be selected to provide a desired RTD through the airflow path. In this embodiment, the depth 58 and width of the flow restriction 50 determine the cross-sectional area of the flow restriction. In this embodiment, the depth 58 of the flow restriction 50 (which is shown in fig. 12) has a minimum dimension in any portion of the airflow path. In this embodiment, the flow restriction 50 is spaced apart from the airflow chamber 51 with an additional air gap 49 disposed between the device housing 38 and the surface of the inwardly extending flange 34 of the second cartridge housing part 18. The airflow through a portion of the aerosol-generating system 10 is illustrated by the dashed arrow in fig. 11.

It should be understood that the above examples are merely examples of the present disclosure and that modifications may be made to the examples within the spirit of the present disclosure. For example, it should be appreciated that in some examples, the device 14 may include at least one of an air inlet 48 and an air gap 49. It should also be appreciated that any suitable number of air inlets 48 and air gaps 49 may be provided to provide the desired aerosol delivery to the user. The aerosol-generating system 10 may comprise a resistive heating element instead of the induction heating assembly 43. The cartridge 12 may comprise a single cartridge housing without the movable first and second cartridge housing parts 16, 18 and the device 14 may not include the pushing element 47 extending into the device cavity. The airflow chambers may be disposed in different locations in the airflow path. The airflow chamber may be disposed between the cartridge housing and other portions of the device housing. The flow restrictions may be arranged in different positions in the airflow path. The flow restriction may be disposed between the cartridge housing and other portions of the device housing.

For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers expressing quantities, amounts, percentages, and so forth, are to be understood as being modified in all instances by the term "about". Moreover, all ranges include the disclosed maximum and minimum points, and include any intervening ranges therein that may or may not be specifically enumerated herein. Thus, in this context, the number a is understood to be 10 percent (10%) of a±a. In this context, the number a may be considered to include values within a general standard error for the measurement of the property of the modification of the number a. In some cases, as used in the appended claims, the number a may deviate from the percentages recited above, provided that the amount of deviation a does not materially affect the basic and novel characteristics of the claimed invention. Moreover, all ranges include the disclosed maximum and minimum points, and include any intervening ranges therein that may or may not be specifically enumerated herein.

Claims

1. An aerosol-generating system, comprising:

a cartridge, the cartridge comprising:

A cartridge housing;

A liquid reservoir configured to hold a liquid aerosol-forming substrate, and

A heating element configured to heat liquid from the liquid reservoir, and

An apparatus, the apparatus comprising:

Wherein:

2. An aerosol-generating system according to claim 1, wherein a flow restriction is arranged in the airflow path between the air inlet and the airflow chamber, and optionally wherein the flow restriction is arranged immediately upstream of the airflow chamber.

3. An aerosol-generating system according to claim 2, wherein at least one of the following holds:

the flow restriction is a portion of the airflow path having a width less than a width of the airflow chamber;

The flow restriction is a portion of the airflow path having a width that is smallest in any portion of the airflow path;

the flow restriction is a portion of the airflow path having a cross-sectional area smaller than a cross-sectional area of the airflow chamber, and

The flow restriction is a portion of the airflow path having a smallest cross-sectional area in any portion of the airflow path.

4. An aerosol-generating system according to claim 2 or claim 3, wherein the aerosol-generating device comprises the flow restriction.

5. An aerosol-generating system according to claim 2 or claim 3, wherein the flow restriction is defined between the cartridge housing and the device housing when the portion of the cartridge is received in the device cavity.

6. An aerosol-generating system according to claim 5, wherein at least a portion of the surface of the cartridge housing defines at least a portion of the surface of the flow restriction and at least a portion of the surface of the device housing defines at least a portion of the surface of the flow restriction.

7. An aerosol-generating system according to any one of claims 1 to 6, wherein at least a portion of the surface of the cartridge housing defines at least a portion of the surface of the airflow chamber and at least a portion of the surface of the device housing defines at least a portion of the surface of the airflow chamber.

8. An aerosol-generating system according to any one of claims 1 to 7, wherein the air inlet of the airflow path is defined between the cartridge and the device when a portion of the cartridge is received in the device cavity.

9. An aerosol-generating system according to any of claims 1 to 8, wherein the pressure sensor is located in a pressure sensor cavity in the device, and optionally wherein an additional airflow path is provided between the airflow cavity and a suction sensor cavity to enable air to flow between the airflow cavity and the suction sensor cavity.

10. An aerosol-generating system according to any of claims 1 to 9, wherein the device cavity comprises:

A substantially closed end opposite the open end, and

Wherein optionally the device cavity interfaces with the airflow path at the substantially closed end.

11. An aerosol-generating system according to claim 10, wherein the device housing comprises a pushing element, and wherein the pushing element extends from the substantially closed end into the device cavity.

12. An aerosol-generating system according to claim 11, wherein the cartridge housing comprises two parts, a first cartridge housing part, and a second cartridge housing part, wherein the second cartridge housing part is movable relative to the first cartridge housing part, and wherein the pushing element is arranged to contact the second cartridge housing part and move the second cartridge housing part relative to the first cartridge housing part when the portion of the cartridge is received in the device cavity.

13. An aerosol-generating system according to claim 11 or claim 12, wherein at least a portion of a surface of the pushing element defines at least a portion of a surface of the airflow chamber when the portion of the cartridge is received in the device chamber.

14. An aerosol-generating system according to any one of claims 1 to 13, wherein the aerosol-generating system further comprises an induction heating assembly comprising an inductor coil and the heating element, wherein the device comprises the inductor coil, and wherein the heating element comprises a susceptor element.

15. An aerosol-generating system according to claim 14, wherein the device is configured to supply a varying current to the inductor coil, wherein the inductor coil is configured to generate an alternating magnetic field when supplied with a varying current, and wherein the inductor coil and susceptor element are arranged such that the varying magnetic field penetrates the susceptor element when the portion of the cartridge is received in the device cavity.