Replaceable cartridge with capillary and air inlet

Abstract

The invention relates to a replaceable cartridge configured for being detachably connectable to an aerosol-generating device comprising: a liquid storage portion for storing an aerosol-forming liquid, the liquid storage portion comprising a liquid outlet for directing the aerosol-forming liquid out of the liquid storage portion, and a capillary being in fluid communication with the liquid storage portion and the liquid outlet, and an air inlet configured for allowing air to enter the liquid storage portion, wherein the air inlet protrudes into the interior of the liquid storage portion. Such a replaceable cartridge reduces or avoids leakage of aerosol-forming liquid out of the cartridge through the air inlet.

Description

[0001] REPLACEABLE CARTRIDGE WITH CAPILLARY AND AIR INLET

[0002] The present invention relates to a replaceable cartridge containing an aerosol-forming liquid to be aerosolized. Cartridges are known which contain a liquid aerosol-forming substrate and a wicking element. These cartridges may be connected to an aerosol-generating device for forming an aerosol. The wicking element normally retains a high volume of the aerosolforming liquid even when the cartridge is depleted. Furthermore, the liquid transfer in these cartridges depends on the correct orientation of the cartridge allowing the transport of the liquid through the wicking element. Close contact between the wicking element and an aerosolization element for forming an aerosol from the aerosol-forming liquid can also lead to the production of harmful and potentially harmful constituents or might hamper the production of the aerosol. Cartridges including liquid aerosol-forming substrate also tend to leak. Liquid transfer in these cartridges including liquid aerosol-forming substrate also may be interrupted.

[0003] It would be desirable to provide a replaceable cartridge which allows the consumption of a larger fraction of aerosol-forming liquid before being depleted. It would furthermore be desirable to provide a replaceable cartridge which would reduce or eliminate the amount of harmful and potentially harmful constituents during production of the aerosol. It would be desirable to provide a cartridge which reduces or avoids leakage of aerosol-forming liquid out of the cartridge. It furthermore would be desirable to provide a replaceable cartridge which would enable a reliable transfer of the aerosol-forming liquid independent of the orientation of the cartridge. It also would be desirable to provide a replaceable cartridge which would ensure a constant supply of aerosol-forming liquid during operation of the aerosol-generating device. It would be desirable to provide a cartridge which could be used irrespective of its orientation without leakage of the aerosol-forming liquid.

[0004] According to an embodiment of the present invention there is provided a replaceable cartridge configured for being detachably connectable to an aerosol-generating device. The replaceable cartridge may comprise a liquid storage portion for storing an aerosol-forming liquid. The liquid storage portion may comprise the liquid outlet for directing the aerosol-forming liquid out of the liquid storage portion. The replaceable cartridge may comprise a capillary. The capillary may be in fluid communication with the liquid storage portion and the liquid outlet. The replaceable cartridge may comprise an air inlet configured for allowing air to enter the liquid storage portion. The air inlet may protrude into the interior of the liquid storage portion.

[0005] According to a further embodiment of the present invention a replaceable cartridge configured for being detachably connectable to an aerosol-generating device is provided. The replaceable cartridge comprises a liquid storage portion for storing an aerosol-forming liquid. The liquid storage portion comprises a liquid outlet for directing the aerosol-forming liquid out of the liquid storage portion. Furthermore, the replaceable cartridge comprises a capillary. The capillary is in fluid communication with the liquid storage portion and the liquid outlet. The replaceable cartridge furthermore comprises an air inlet configured for allowing air to enter the liquid storage portion. The air inlet protrudes into the interior of the liquid storage portion.

[0006] The air inlet protruding into the interior of the liquid storage portion may allow air to enter the liquid storage portion. This may enable the replacement of the consumed aerosolforming liquid by air entering via the air inlet. The air inlet may reduce or avoid the occurrence of low pressure in the liquid storage portion when the aerosol-forming liquid is consumed during operation of the aerosol-generating device with the replaceable cartridge. The air inlet protruding into the interior of the liquid storage portion may avoid or reduce the leakage of aerosol-forming liquid out of the liquid storage portion. The air inlet protruding into the interior of the liquid storage portion may also avoid or reduce the leakage of aerosol-forming liquid through the air inlet irrespective of the orientation of the replaceable cartridge.

[0007] The air inlet may be configured for allowing air to enter the liquid storage portion. The air may replace the aerosol-forming liquid being evaporated during operation of the aerosolgenerating device.

[0008] This may enable a continuous transport of the aerosol-forming liquid through the capillary to the liquid outlet during operation of the aerosol-generating device.

[0009] The term “capillary” may refer to a narrow space within the replaceable cartridge configured for allowing the flowing of the aerosol-forming liquid without the assistance of any external forces, such as gravity. The “capillary” may be even configured to allow the flowing of the aerosol-forming liquid against the influence of external forces, such as gravity. The capillary may allow conveying of the aerosol-forming liquid from the liquid storage portion to the liquid outlet via capillary forces. The capillary forces may allow the flowing of the aerosol-forming liquid based on a combination of a surface tension of the aerosol-forming liquid with adhesive forces between the walls of the capillary and the aerosol-forming liquid.

[0010] The replaceable cartridge may furthermore comprise a housing. The housing may enclose the liquid storage portion. The air inlet may extend from the housing into the interior of the liquid storage portion.

[0011] This may allow an easy integration of the air inlet into the housing of the replaceable cartridge.

[0012] The housing may comprise or may be made of one of PEEK (polyether ether ketone), PP (polypropylene), PE (polyethylene) or PET (polyethylene terephthalate). PP, PE and PET are particularly cost-effective and easy to mold, in particular to extrude.

[0013] A cross-sectional area of the air inlet at the housing may be larger than a cross- sectional area of the air inlet in the interior of the liquid storage portion.

[0014] This may allow an easy entry of air through the air inlet from the housing into the interior of the liquid storage portion. As used herein, the term “cross-sectional area of the air inlet” refers to the cross-section of the air inlet perpendicular to the longitudinal length of the air inlet. The air inlet may extend along a longitudinal air inlet axis. The term “cross-sectional area of the air inlet” may refer to the cross-section of the air inlet perpendicular to the longitudinal air inlet axis.

[0015] In particular, the air inlet may comprise an air inlet sidewall extending from the housing into the interior of the liquid storage portion. This air inlet sidewall may circumscribe an airflow path of the air inlet. The airflow path may lead from the housing into the interior of the liquid storage portion.

[0016] A cross-sectional area of the air inlet may decrease from the housing towards the interior of the liquid storage portion. In particular, the airflow path of the air inlet being circumscribed by the air inlet sidewall may decrease from the housing towards the interior of the liquid storage portion.

[0017] The housing may comprise a housing sidewall. The housing sidewall may be connected with the air inlet sidewall. The housing sidewall and the air inlet sidewall may form one continuous sidewall extending from the housing into the interior of the liquid storage portion.

[0018] This may provide a continuous sidewall furthermore reducing the leakage of the aerosol-forming liquid.

[0019] The air inlet may be funnel-shaped. In particular, the air inlet sidewall may circumscribe a funnel-shaped air inlet airflow path.

[0020] This funnel-shaped air inlet may allow an easy entry of air into the liquid storage portion. This funnel-shaped air inlet may also reduce the leakage of aerosol-forming liquid out of the liquid storage portion through the air inlet.

[0021] The air inlet may comprise a first air inlet end and a second air inlet end. The second air inlet end may be the end of the air inlet which is located in the interior of the liquid storage portion. The second air inlet end may be located the furthest in the liquid storage portion. The first air inlet end may be the end of the air inlet being located opposite of the second air inlet end. The first air inlet end may be located near or adjacent to the housing of the cartridge. The second air inlet end may be located near or adjacent to the centre of the liquid storage portion.

[0022] One or both of the first air inlet and second air inlet end may be covered with a perforated membrane. The perforated membrane may provide some resistance to the airflow into the liquid storage portion via the air inlet. The perforated membrane may allow the entry of air through the air inlet and the perforations of the membrane into the interior of the liquid storage portion. The perforated membrane may be deformed to an extent in order to compensate for negative pressure in the liquid storage portion when using the aerosol-forming liquid. The perforated membrane may be flexible. The perforated membrane may be configured to bulge towards the interior of the liquid storage portion upon application of a negative pressure. The perforated membrane may be configured to bulge into the interior of the air inlet upon application of a negative pressure. The perforated membrane may reduce or avoid leakage of aerosol-forming liquid out of the liquid storage portion through the air inlet.

[0023] The perforated membrane may comprise or be fabricated from a material selected from the group consisting of: rubber, polyolefins, elastomer, ethylene vinyl acetate or combinations thereof.

[0024] Preferably, the first air inlet end may be covered with the perforated membrane.

[0025] The capillary may comprise a first capillary end and an opposing second capillary end. The air inlet may be located at or adjacent to the first end of the capillary. The liquid outlet may be located at or adjacent to the second end of the capillary.

[0026] This may allow a user to easily consume the aerosol-forming liquid being directed out of the replaceable cartridge through the liquid outlet, at the same time allowing air to enter the liquid storage portion through the opposing first end.

[0027] The capillary may be in fluid communication with the liquid storage portion at the first capillary end. The capillary may be in fluid communication with the liquid outlet at the second capillary end.

[0028] This may allow the capillary to direct aerosol-forming liquid from the liquid storage portion at the first end of the capillary to the liquid outlet located at the second end of the capillary.

[0029] The replaceable cartridge may comprise a first cartridge end and a second opposing cartridge end. The first end of the capillary may be located at or adjacent to the first cartridge end. The second end of the capillary may be located at or adjacent to the second cartridge end. This may allow an easy entry of air into the liquid storage portion at one first end of the cartridge. This may allow an easy exit of aerosol-forming liquid out of the liquid storage portion of the cartridge at an opposing second end of the cartridge without interfering with the entry of air into the liquid storage portion. This may allow an easy transport of aerosol-forming liquid from one end of the cartridge to another end of the cartridge via the capillary.

[0030] The air inlet may be located opposite of the liquid outlet in the replaceable cartridge.

[0031] The sidewall of the air inlet extending from the housing into the interior of the liquid storage portion may have a height. The height of the sidewall in the interior may be higher than the maximum height of the aerosol-forming liquid in the liquid storage portion. This may ensure that the aerosol-forming liquid does not leak out of the liquid storage portion through the air inlet.

[0032] The height of the sidewall in the interior may be defined as the distance between the air inlet opening in the housing and the end of the air inlet sidewall being located in the interior of the liquid storage portion furthest away from the air inlet opening in the housing. The liquid storage portion may be partially filled with the aerosol-forming liquid. In particular, the liquid storage portion may comprise an aerosol-forming liquid and a portion being free of the aerosol-forming liquid. The portion being free of the aerosol-forming liquid may include air. The air inlet may be in air communication with the portion of the liquid storage portion being free of the aerosol-forming liquid. The air inlet may be configured to provide the air portion of the liquid storage portion being free of the aerosol-forming liquid with air for replacing any aerosol-forming liquid being evaporated.

[0033] A distance between the opposing sidewalls of the air inlet may be larger than the maximum cross-sectional width of the capillary.

[0034] This may ensure that the capillary can still transport the aerosol-forming liquid towards the liquid outlet even in the case that liquid is present in the air inlet.

[0035] The housing of the replaceable cartridge may comprise an outer shell and an inner shell. The inner shell may be located in the interior of the cartridge opposite of the outer shell. The capillary may be formed between the outer shell and the inner shell. The inner shell may be located in the interior of the cartridge wherein an inner main surface of the inner shell circumscribes the liquid storage portion of the replaceable cartridge. An outer main surface of the inner shell may be located opposite of the outer shell. The outer shell may comprise an inner main surface and an opposing outer main surface. The outer main surface of the outer shell may face outwards in relation to the liquid storage portion of the replaceable cartridge. The outer main surface of the outer shell may form an outer surface of the housing of the replaceable cartridge. The inner main surface of the outer shell may be located opposite of the outer main surface of the inner shell. The capillary may be formed between the outer shell and the inner shell, in particular between the inner main surface of the outer shell and the outer main surface of the inner shell.

[0036] This may allow the capillary to be formed throughout the housing of the replaceable cartridge. This may allow the capillary to be formed around the circumference of the liquid storage portion. This may allow the capillary to extend from the first capillary end at or adjacent to the air inlet to the second capillary end at or adjacent to the liquid outlet.

[0037] One or both of the outer shell and the inner shell may comprise a material that is hydrophilic with a water contact angle smaller than 90 degrees. In particular, the material may be present on one or both of the inner main surface of the outer shell and the outer main surface of the inner shell between which the capillary is formed. The material may be selected from a group consisting of: hydrophilic polymer, glass, silicon, and metals. Examples of hydrophilic polymer may be one or more of polycarbonate (PC), or poly(methyl methacrylate) (PMMA) or polyethylene terephthalate (PET).

[0038] The outer shell and the inner shell may have any shape suitable to form a capillary between the inner main surface of the outer shell and the outer main surface of the inner shell. Apart from having at tubular or cylindrical shape, the inner and the outer shell may be hollow polygonal prisms. In this case, the surface of the cross-section of the capillary may have a hollow polygonal shape. For example, the outer shell and the inner shell may be hollow rectangular prisms. In this case the surface of the cross-section of the capillary perpendicular to the longitudinal length of the capillary may have a hollow rectangular shape.

[0039] A distance or the width between the outer shell and the inner shell may be between 0.05 millimeters and 0.9 millimeters. In particular, a distance or width between the inner main surface of the outer shell and the outer main surface of the inner shell may be between 0.1 millimeter and 0.7 millimeters, preferably the distance or width between the inner main surface of the outer shell and the outer main surface of the inner shell may range from 0.15 millimeters to 0.5 millimeters. The capillary therefore may have a cross-sectional width of between 0.05 millimeters and 0.9 millimeters.

[0040] A distance in this range may particularly well suited in order to transport the aerosolforming liquid via capillary action.

[0041] A cross-sectional width of the capillary or the distance between the outer shell and the inner shell may be larger at the second capillary end than at the first capillary end. This may ensure that even when the replaceable cartridge is turned around into an inverted position where fluid communication between the aerosol-forming liquid in the liquid storage portion and the capillary may be interrupted that sufficient aerosol-forming liquid can be conveyed via the capillary to the liquid outlet as long as aerosol-forming liquid is present in the capillary.

[0042] The capillary may comprise protrusions. The protrusions may be in contact with one or both of the inner shell and the outer shell. Preferably, the protrusions may be in contact with both the inner shell and the outer shell. The protrusions may be in contact with the outer main surface of the inner shell and the inner main surface of the outer shell. The protrusions may serve in order to maintain the same distance between the inner shell and the outer shell for at least a part of the length of the capillary. The protrusions may extend along the longitudinal axis of the replaceable cartridge. The protrusions may extend within the interior of the capillary. This may ensure that a same distance between the inner shell and the outer shell can be maintained along the longitudinal axis of the replaceable cartridge.

[0043] A portion of the capillary adjacent to the liquid outlet may be free of the protrusions. This may enable the aerosol-forming liquid to be transported freely to the liquid outlet. This may still enable the protrusions present in the capillary to maintain a constant width of the capillary. The protrusions may comprise ribs. The ribs may extend at least a part of the length of the capillary. This may enable the ribs to maintain a constant width along at least a part of the length of the capillary. The ribs may comprise a width and a length. The length of the ribs may be larger than the width. This may ensure that the ribs can extend along at least a part of the length of the capillary without interfering with the capillary transfer of the aerosol-forming liquid.

[0044] The protrusions or the ribs may be located on one or both of the inner main surface of the outer shell or the outer main surface of the inner shell.

[0045] The air inlet sidewall may be connected to the outer shell of the housing. The outer shell of the housing may form a continuous sidewall with the air inlet sidewall. The first capillary end may be formed between the outer shell of the housing and the inner shell of the housing adjacent to the air inlet sidewall.

[0046] This may provide a simple design for providing the first capillary end being in liquid communication with the liquid storage portion adjacent to the air inlet.

[0047] As used herein, the term "aerosol-forming liquid" relates to a liquid capable of releasing volatile compounds that can form an aerosol upon heating the aerosol-forming liquid. The aerosol-forming liquid may contain both, solid and liquid aerosol-forming material or components. The aerosol-forming liquid may comprise a tobacco-containing material containing volatile tobacco flavor compounds, which are released from the liquid upon heating. Alternatively or additionally, the aerosol-forming liquid may comprise a non-tobacco material. The aerosol-forming liquid in the liquid storage portion of the replaceable cartridge may comprise at least one aerosol-former. An aerosol-former is any suitable known compound or mixture of compounds that, in use, facilitates formation of a dense and stable aerosol and that is substantially resistant to thermal degradation at the temperature of operation of the aerosolforming device in the system. Suitable aerosol-formers are well known in the art and include, but are not limited to: polyhydric alcohols, such as triethylene glycol, 1 ,3-butanediol and glycerine; esters of polyhydric alcohols, such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate. Aerosol formers may be polyhydric alcohols or mixtures thereof, such as triethylene glycol, 1 ,3-butanediol and glycerine. The aerosol-former may be propylene glycol. The aerosol former may comprise both glycerine and propylene glycol. The aerosol-forming liquid may comprise 50 weight percent to about 18 weight percent of water. This may ensure that the viscosity of the liquid is sufficiently low. This may enable a mesh or a liquid-conveying susceptor to evaporate the aerosol-forming liquid.

[0048] The aerosol-forming liquid may comprise other additives and ingredients, such as flavourants. The aerosol-forming liquid may comprise water, solvents, ethanol, plant extracts and natural or artificial flavours. The aerosol-forming liquid may comprise nicotine. The aerosol-forming liquid may have a nicotine concentration of between about 0.5 percent and about 10%, for example about 2 percent.

[0049] The viscosity of the aerosol-forming liquid may range from 15 mPa.s to 70 mPa.s, preferably from 20 mPa.s to 60 mPa.s. The density of the aerosol-forming liquid may be in the range from 900 kg / m3to 1100 kg / m3, preferably 1000 kg / m3. the surface tension of the aerosolforming liquid may be in the range of 35 mN / m to 45 mN / m, preferably 40 mN / m.

[0050] A maximum distance between the outer shell and the inner shell may be smaller than a distance between the opposing sidewalls of the air inlet. In particular, a maximum distance between the inner main surface of the outer shell and the outer main surface of the inner shell may be smaller than a distance between the opposing sidewalls of the air inlet.

[0051] This may ensure a reliable transport of aerosol-forming liquid through the capillary. This may also ensure a reliable entry of air into the liquid storage portion through the air inlet.

[0052] The overall geometric shape of the inner shell may conform to the overall geometric shape of the outer shell. This may allow the formation of the capillary between the outer shell of the housing and the inner shell. Preferably, the outer shell and the inner shell may have a tubular or cylindrical shape. The outer shell and the inner shell may be concentric in order to allow the formation of the capillary.

[0053] The replaceable cartridge may furthermore comprise a longitudinal axis. A first portion of the capillary may extend along the longitudinal axis. The first portion of the capillary may have a circular cross-sectional area, preferably a ring-shaped cross-sectional area. The circular cross-sectional area may extend perpendicular to the longitudinal axis of the replaceable cartridge.

[0054] As used herein, the term “cross-sectional area of the capillary” refers to the crosssection of the capillary perpendicular to the longitudinal length of the capillary. In particular, cross-sections in different areas of the longitudinal length of the capillary may have the same area or surface of the cross-section. This may allow a constant and reliable transport of the aerosol-forming liquid through the capillary via capillary action.

[0055] A first portion of the capillary having a circular cross-sectional area may allow a reliable and quick transfer of aerosol-forming liquid from the liquid storage portion to the liquid outlet owing to the large area of the capillary.

[0056] The replaceable cartridge may furthermore comprise a second portion of the capillary. The second portion of the capillary may extend transversely to the longitudinal axis of the replaceable cartridge. Preferably, the second portion of the capillary may extend perpendicular to the longitudinal axis of the replaceable cartridge.

[0057] A second portion of the capillary extending perpendicular to the longitudinal axis of the replaceable cartridge may be located at or adjacent to the liquid outlet.

[0058] This may ensure that aerosol-forming liquid can be transferred to the liquid outlet via the capillary reliably and in large quantities.

[0059] The air inlet protruding into the interior of the liquid storage portion may be located centrally at the first cartridge end. The longitudinal air inlet axis may coincide with the longitudinal axis of the cartridge. The liquid outlet may comprise a liquid-conveying susceptor. The liquid-conveying susceptor may be configured for directing the aerosol-forming liquid out of the liquid storage portion. The liquid-conveying susceptor may be configured for heating the aerosol-forming liquid during operation of the aerosol-generating device.

[0060] Such a liquid-conveying susceptor may ensure that the aerosol-forming liquid is reliably transferred through the liquid outlet. Such a liquid-conveying susceptor may provide a reliable evaporation of the aerosol-forming liquid transported through the liquid-conveying susceptor.

[0061] The liquid-conveying susceptor may comprise filaments arranged side by side. The filaments may be configured to convey aerosol-forming liquid. The filaments may be configured to be inductively heatable.

[0062] The liquid conveying susceptor may be an inductively heatable wick element.

[0063] As used herein, the tern "liquid-conveying susceptor" refers to a susceptor which is capable to perform two functions, conveying and heating aerosol-forming liquid. Likewise, the liquid-conveying susceptor may be considered as an inductively heatable liquid conduit. Using such a liquid-conveying susceptor advantageously reduces the number of required components and thus facilitates the manufacturing of the cartridge, because it avoids having separate means for conveying and heating the aerosol-forming liquid.

[0064] As used herein, the term "susceptor " refers to a component comprising at least one susceptor material that is capable to convert electromagnetic energy into heat when subjected to an alternating magnetic field. This may be the result of at least one of hysteresis losses or eddy currents induced in the susceptor material, depending on the electrical and magnetic properties of the susceptor material. Hysteresis losses occur in ferromagnetic or ferrimagnetic susceptor materials due to magnetic domains within the material being switched under the influence of an alternating electromagnetic field.

[0065] Eddy currents are induced in electrically conductive susceptor materials. In case of an electrically conductive ferromagnetic or ferrimagnetic susceptor material, heat is generated due to both, eddy currents and hysteresis losses.

[0066] In general, the liquid-conveying susceptor arrangement may have any shape and configuration suitable to convey aerosol-forming liquid from the liquid outlet. In particular, the liquid-conveying susceptor arrangement may comprise a wick element. The configuration of the wick element may be a stranded wire, a stranded rope of material, a mesh, a mesh tube, several concentric mesh tubes, a cloth, sheets of material, or a foam (or other porous solid) with sufficient porosity, a roll of fine metal mesh or some other arrangement of metal foil, fibers or mesh, or any other geometry that is appropriately sized and configured to carry out the wicking action as described herein.

[0067] In particular, the liquid-conveying susceptor arrangement may comprise a filament bundle including a plurality of filaments. Preferably, the filament bundle is an unstranded filament bundle. In an unstranded filament bundle, the filaments of the filament bundle run next to each other without crossing each other, preferably along the entire length extension of the filament bundle. Likewise, the filament bundle may comprise a stranded portion, in which the filaments of the filament bundle are stranded. A stranded portion may enhance the mechanical stability of the filament bundle. Using filaments for conveying liquids is particularly advantageous because filaments inherently provide a capillary action. Moreover, in a filament bundle, the capillary action is further enhanced due to the narrow spaces formed between the pluralities of filaments when being bundled. In particular, this applies for a parallel arrangement of the filaments along which the capillary action is constant as the narrow spaces between the filaments do not vary along the parallel arrangement.

[0068] As an example, the filament bundle may comprise a parallel-bundle portion along at least a portion of its length extension in which the plurality of filaments may be arranged parallel to each other. The parallel-bundle portion may be arranged at one end portion of the filament bundle or between both end portions of the filament bundle. Alternatively, the parallel-bundle portion may extend along the entire length dimension of the filament bundle.

[0069] As another example, the filament bundle may comprise a soaking section and an evaporation section adjacent to the soaking section. The soaking section may be in fluid communication with the capillary for receiving the aerosol-forming liquid. The evaporation section may be located near or adjacent to a heating element of an aerosol-generating device when the device is connected to the replaceable cartridge.

[0070] The filament bundle may also be a linear filament bundle, that is, a substantially straight, non-curved or non-bent filament bundle, wherein one end portion of the filament bundle may be arranged in or adjacent to the liquid outlet, and the other end portion of the filament bundle may be arranged outside the liquid outlet.

[0071] At least a portion of the filaments is made of an inductively heatable material. The inductively heatable susceptor material may comprise or may be made of one of a ferrite, aluminium, iron, nickel, copper, bronze, cobalt, a nickel alloy, plain-carbon steel, stainless steel, ferritic stainless steel, ferromagnetic stainless steel, martensitic stainless steel, or austenitic stainless steel.

[0072] The above-mentioned perforated membrane may slow the pace of entry of air through the air inlet into the liquid storage portion. This may allow more room to adjust the shape of the liquid conveying susceptor.

[0073] Another aspect of the present invention provides an aerosol-generating system. The aerosol-generating system may comprise a replaceable cartridge as described herein. The aerosol-generating system may comprise an aerosol-generating device. The aerosolgenerating device may be configured to be detachably connectable to the cartridge. A further aspect of the present invention provides an aerosol-generating system. The aerosol-generating system comprises a replaceable cartridge as described herein. The aerosol-generating system furthermore comprises an aerosol-generating device being configured to be detachably connectable to the cartridge.

[0074] The aerosol-generating device may comprise a heating element configured for heating the aerosol-forming liquid. The heating element therefore may assist in the formation of an aerosol from the aerosol-forming liquid.

[0075] The aerosol-generating device may comprise an inductive heating arrangement, such as an induction coil. The induction coil may be configured for heating the liquid-conveying susceptor. The aerosol-generating device may also comprise the liquid-conveying susceptor. The aerosol-generating device may comprise a connector element configured for being connectable to the replaceable cartridge. The connector element may comprise the liquidconveying susceptor. The liquid-conveying susceptor may comprise a conduit for conveying the aerosol-forming liquid out of the replaceable cartridge. The liquid-conveying susceptor may comprise a susceptor element configured for heating an aerosol-forming liquid being conveyed through the conduit for generating an aerosol. The susceptor element may at least partly circumscribe the conduit for conveying the aerosol-forming liquid.

[0076] Instead of the susceptor element, the connector element, in particular the conduit of the connector element may include filaments or a bundle of filaments for conveying the aerosol-forming liquid. The filaments may be configured to be inductively heatable by the induction coil.

[0077] The inductive heating arrangement may comprise an inductor coil and a power supply configured to provide high frequency oscillating current to the inductor coil. As used herein, a high frequency oscillating current means an oscillating current having a frequency of between about 500 kHz and about 30 MHz. The heater may advantageously comprise a DC / AC inverter for converting a DC current supplied by a DC power supply to the alternating current. The inductor coil may be arranged to generate a high frequency oscillating electromagnetic field on receiving a high frequency oscillating current from the power supply. The inductor coil may be arranged to generate a high frequency oscillating electromagnetic field in the device cavity. In some embodiments, the inductor coil of the aerosol-generating device may substantially circumscribe the liquid outlet of the cavity, when the replaceable cartridge is connected to the device.

[0078] The liquid-conveying susceptor may be arranged such that, when the replaceable cartridge is connected to the aerosol-generating device, the oscillating electromagnetic field generated by the inductor coil induces a current in the susceptor, causing the liquid-conveying susceptor to heat up. In these embodiments, the aerosol-generating device is preferably capable of generating a fluctuating electromagnetic field having a magnetic field strength (H- field strength) of between 1 and 5 kilo amperes per meter (kA m), preferably between 2 and 3 kA / m, for example about 2.5 kA / m. The electrically-operated aerosol-generating device is preferably capable of generating a fluctuating electromagnetic field having a frequency of between 1 and 30 MHz, for example between 1 and 10 MHz, for example between 5 and 7 MHz.

[0079] The aerosol-generating device may comprise a heating element. The heating element may be an electrically resistive heating element. The heating element may be co-axially arranged around at least a part of the conduit of the connector element. The heating element may have a substantially circular cross-section. The heating element may have a skewed circular cross-section. The heating element may have a ring shape. The heating element may have a hollow tubular shape. The heating element may be in contact with the aerosol-forming liquid located in the conduit.

[0080] The aerosol-generating device of the aerosol-generating system may comprise one or more of: a battery, a communication interface for a user, control circuitry for controlling the induction coil configured to heat the liquid-conveying susceptor.

[0081] The aerosol-generating device may comprise a power supply, typically a battery, within the casing of the aerosol-generating device. In one embodiment, the power supply is a Lithium- ion battery. Alternatively, the power supply may be a Nickel-metal hydride battery, a Nickel cadmium battery, or a Lithium based battery, for example a Lithium-Cobalt, a Lithium-lron- Phosphate, Lithium Titanate or a Lithium-Polymer battery. As an alternative, the power supply may be another form of charge storage device such as a capacitor. The power supply may require recharging and may have a capacity that enables to store enough energy for one or more usage experiences; for example, the power supply may have sufficient capacity to continuously generate aerosol for a period of around six minutes or for a period of a multiple of six minutes. In another example, the power supply may have sufficient capacity to provide a predetermined number of puffs or discrete activations of the aerosolization element.

[0082] The aerosol-generating device may comprise electric control circuitry. The electric circuitry may comprise a microprocessor, which may be a programmable microprocessor. The microprocessor may be part of a control unit. The electric circuitry may comprise further electronic components. The electric circuitry may be configured to regulate a supply of power to the aerosolization element. Power may be supplied to the heating element or the induction coil continuously following activation of the aerosol-generating device or may be supplied intermittently, such as on a puff-by-puff basis. The power may be supplied to the heating element or the induction coil in the form of pulses of electrical current. The electric circuitry may be configured to monitor the electrical resistance of the heating element or the induction coil, and preferably to control the supply of power to the heating element or the induction coil dependent on the electrical resistance of the aerosolization element. The aerosol-generating device may include a user interface to activate the device, for example a button to turn on and off the aerosol-generating device, in particular the aerosolization element. The aerosol-generating device may also be activated by a puff sensor.

[0083] The user interface also may comprise a display to indicate a state of the device or the filling level of the replaceable cartridge.

[0084] The air inlet of the replaceable cartridge may comprise a sidewall and a length of the sidewall of the air inlet within the liquid storage portion may range from 0.5 centimeters to 3 centimetres, preferably from 0.5 centimetres to 2.5 centimetres, more preferably from 1 centimetre to 2 centimetres. A distance between the second air inlet end being located in the liquid storage portion and the maximum height of the aerosol-forming liquid in the liquid storage portion may be between 1 millimeter to 10 millimeters, preferably between 3 millimeters to 8 millimeters, more preferably between 5 millimeters to 7 millimeters. This distance may avoid or reduce any leakage of aerosol-forming liquid out of the replaceable cartridge through the air inlet. The maximum volume of the aerosol-forming liquid within the liquid storage portion may be between 1.5 and 3 milliliters, preferably 2 milliliters.

[0085] Below, there is provided a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0086] Example Ex1 : A replaceable cartridge configured for being detachably connectable to an aerosol-generating device comprising: a liquid storage portion for storing an aerosol-forming liquid, the liquid storage portion comprising a liquid outlet for directing the aerosol-forming liquid out of the liquid storage portion, and a capillary being in fluid communication with the liquid storage portion and the liquid outlet, and an air inlet configured for allowing air to enter the liquid storage portion, wherein the air inlet protrudes into the interior of the liquid storage portion.

[0087] Example Ex2: The replaceable cartridge of the example EX1 , furthermore comprising a housing enclosing the liquid storage portion, wherein the air inlet extends from the housing into the interior of the liquid storage portion.

[0088] Example Ex3: The replaceable cartridge of the preceding examples, wherein a cross sectional area of the air inlet at the housing is larger than a cross-sectional area of the air inlet in the interior of the liquid storage portion, preferably wherein a cross-sectional area of the air inlet decreases from the housing towards the interior of the liquid storage portion.

[0089] Example Ex4: The replaceable cartridge of any of the preceding examples, wherein the air inlet is funnel-shaped. Example Ex5: The replaceable cartridge of any of the preceding examples, wherein the capillary comprises a first end and an opposing second end, wherein the air inlet is located at or adjacent to the first end and wherein the liquid outlet is located at or adjacent to the second end.

[0090] Example Ex6: The replaceable cartridge of the preceding example, wherein one or both, the capillary is in fluid communication with the liquid storage portion at the first end and the capillary is in fluid communication with the liquid outlet at the second end.

[0091] Example Ex7: The replaceable cartridge of any of the preceding examples, wherein the air inlet comprises a sidewall extending from the housing into the interior of the liquid storage portion, preferably wherein a height of the sidewall in the interior is higher than a maximum height of the aerosol-forming liquid in the liquid storage portion.

[0092] Example Ex8: The replaceable cartridge of the preceding example, wherein a distance between opposing sidewalls of the air inlet is larger than a maximum cross-sectional width of the capillary.

[0093] Example Ex9: The replaceable cartridge of any of the preceding examples, wherein the air inlet is located opposite of the liquid outlet.

[0094] Example Ex10: The replaceable cartridge of any of the preceding examples, furthermore comprising a housing enclosing the liquid storage portion, wherein the housing comprises an outer shell and an inner shell, wherein the inner shell is located in the interior of the cartridge and wherein the capillary is formed between the outer shell and the inner shell.

[0095] Example Ex11 : The replaceable cartridge of the preceding example, further dependent on example EX7, wherein a maximum distance between the outer shell and the inner shell is smaller than a distance between opposing sidewalls of the air inlet.

[0096] Example Ex12: The replaceable cartridge of any of the preceding examples EX10 or Ex11 , wherein the overall geometric shape of the inner shell conforms to the overall geometric shape of the outer shell, preferably wherein the outer shell and the inner shell have a tubular or cylindrical shape.

[0097] Example Ex13: The replaceable cartridge of any of the preceding examples, further comprising a longitudinal axis, wherein a first portion of the capillary extending along the longitudinal axis has a circular cross-sectional area, preferably a ring-shaped cross-sectional area, preferably wherein the circular cross-section area extends perpendicular to the longitudinal axis.

[0098] Example Ex14: The replaceable cartridge of any of the preceding examples, further comprising a longitudinal axis, wherein a second portion of the capillary extends transversal to the longitudinal axis, preferably wherein the second portion of the capillary extends perpendicular to the longitudinal axis. Example Ex15: The replaceable cartridge of any of the preceding examples, wherein the liquid outlet comprises a liquid-conveying susceptor configured for directing the aerosolforming liquid out of the liquid storage portion and configured for inductively heating the aerosol-forming liquid during operation of the aerosol-generating device.

[0099] Example Ex16: The replaceable cartridge of the preceding example, wherein the liquidconveying susceptor comprises filaments arranged side by side configured to convey the aerosol-forming liquid, wherein the filaments are inductively heatable.

[0100] Example Ex17: The replaceable cartridge of any of the preceding examples, wherein the air inlet is configured for allowing air to enter the liquid storage portion in order to replace the aerosol-forming liquid being evaporated during operation of the aerosol-generating device.

[0101] Example Ex18: The replaceable cartridge of any of the preceding examples, wherein the air inlet comprises a first air inlet end and an opposing second air inlet end, wherein the second air inlet end is located in the interior of the liquid storage portion and wherein one or both the first and the second air inlet end are covered with a perforated membrane, preferably wherein the first air inlet end is covered with the perforated membrane.

[0102] Example Ex19: An aerosol-generating system comprising a replaceable cartridge of any of the preceding examples Ex1 to Ex18, and an aerosol-generating device being configured to be detachably connectable to the cartridge.

[0103] Example Ex20: The aerosol-generating system of the preceding example, wherein the aerosol-generating device comprises a heating element configured for heating the aerosolforming liquid, preferably wherein the aerosol-generating device comprises an induction coil configured for heating the liquid-conveying susceptor.

[0104] Example Ex21 : The aerosol-generating system of the preceding examples Ex19 or Ex20, wherein the aerosol-generating device comprises one or more of: a battery, a communication interface for a user, control circuitry for controlling an induction coil configured to heat the liquid-conveying susceptor.

[0105] Features described in relation to one embodiment may equally be applied to other embodiments of the invention.

[0106] The invention will be further described, by way of example only, with reference to the accompanying drawings in which:

[0107] Fig. 1 shows a schematic cross-sectional view of a replaceable cartridge with a capillary and an air inlet;

[0108] Fig. 2A and 2B depict cross-sectional views along different sections of the cartridge in Fig. 1 marked with the lines;

[0109] Fig. 3 depicts a cross-sectional view of the replaceable cartridge of fig. 1 turned around by 180 degrees; Fig. 4 depicts a schematic perspective view of an inner shell with protrusions for maintaining a distance between the inner shell and outer shell;

[0110] Fig. 5A and 5B depict cross-sectional views of different embodiments of the replaceable cartridge including a perforated membrane; and

[0111] Fig. 6A and 6B depict an aerosol-generating device to be detachably connected to the replaceable cartridge and an aerosol-generating system including the aerosol-generating device and the cartridge being detachably connected to the aerosol-generating device.

[0112] In the following elements with the same functionality are marked with the same reference numerals throughout all the figures

[0113] Fig. 1 depicts a schematic cross-sectional view of a replaceable cartridge 10 including an air inlet 12 at one end of the replaceable cartridge and a liquid outlet 16 at an opposing end of the replaceable cartridge. The replaceable cartridge comprises a liquid storage portion 22. A portion of the liquid storage portion includes aerosol-forming liquid 20A, whereas another portion 20B of the liquid storage portion is free of the aerosol-forming liquid. This portion 20 B houses air. The air inlet 12 protrudes into the interior of the liquid storage portion 22 with sidewalls 12A of the air inlet protruding into the liquid storage portion 22. A height 34 of the sidewalls 12A of the air inlet in the liquid storage portion is larger than a maximum height 32 of the aerosol-forming liquid 20A in the liquid storage portion. This ensures that the aerosolforming liquid does not leak out of the cartridge 10 through the air inlet 12. The air inlet 12 is in air communication with the portion 20B of the liquid storage portion housing air. This ensures that any aerosol-forming liquid 20A evaporated can be replaced by air through the air inlet 12. The replaceable cartridge 10 comprises a capillary 14 which is formed between an inner shell 28 and an outer shell 26. In particular, the capillary 14 is formed between an outer main surface 28B of the inner shell 28 and an inner main surface 26A of the outer shell 26. The capillary 14 includes a first end 14A of the capillary which is in fluid communication with the aerosol-forming liquid 20A in the liquid storage portion 22. The capillary also includes a second end 14B of the capillary which is in fluid communication with the liquid outlet 16. The capillary is configured to convey aerosol-forming liquid 20A out of the liquid storage portion 22 through the first end 14A to the second end 14B of the capillary so that the aerosol-forming liquid can reach the liquid outlet 16. The outer shell 26 in this embodiment also forms a part of the housing 23 of the replaceable cartridge 10. The outer shell 26 can form a continuous wall with the sidewall 12A of the air inlet.

[0114] The replaceable cartridge 10 has a longitudinal axis 18 and comprises two separate capillary portions, a first capillary portion 14C, which runs along, in particular parallel to the longitudinal axis 18 and a second capillary portion 14D which runs transversely, in particular perpendicular to the longitudinal axis 18. Depending on the design of the capillary 14, the capillary 14 also may comprise two separate second portions 14D, running transversely to the longitudinal axis 18. In particular, a second capillary portion 14D may be present adjacent to the first end 14A of the capillary and another second capillary portion 14D might be present adjacent to the liquid outlet 16. In particular, the second capillary portion 14D being adjacent to the liquid outlet 16 may ensure that enough aerosol-forming liquid 20A is supplied to the liquid outlet for evaporization. The replaceable cartridge 10 also includes a first cartridge end 10A and a second opposing cartridge end 10B. The air inlet 12 is located centrally at the first cartridge end 10A and includes a longitudinal air inlet axis. The air inlet 12 extends along this longitudinal air inlet axis, and the air inlet axis coincides with the longitudinal axis 18 of the cartridge.

[0115] Fig. 2A depicts a schematic cross-sectional view of the replaceable cartridge 10 shown in Fig. 1 along the dashed line 24 shown in Fig. 1. Fig. 2A shows an outer shell 26 with an inner shell 28 and the capillary 14 formed between the inner shell and the outer shell. The capillary 14 in the first portion 14 C of the capillary has a circular, in particular a ring-shaped cross-section. Fig. 2A also shows the liquid storage portion 22 with the partition 20B including air.

[0116] Fig. 2B depicts a schematic cross-sectional view of the replaceable cartridge 10 shown in Fig. 1 along the dashed line 30 shown in Fig. 1. This Fig. 2B depicts the same elements as Fig. 2A with the exception that additionally the air inlet 12 with the air inlet sidewall 12A is visible which extends into the liquid storage portion 22 and which is surrounded by aerosolforming liquid 20A.

[0117] Fig. 3 shows a schematic cross-sectional view of the replaceable cartridge 10 shown in Fig. 1 turned around by 180 degrees. It can clearly be seen that the capillary 14 is not in fluid communication with the aerosol-forming liquid 20A in the liquid storage portion 22 anymore. However, there is enough aerosol-forming liquid 20A in the capillary 14 in order to provide enough liquid for a few puffs to be taken by a user. The liquid meniscus 20C located at the first end 14A of the capillary is at atmospheric pressure and resists the movement of the aerosol-forming liquid around the liquid outlet 16. Nevertheless, even in the inverted position shown in Fig. 3, a user can still take a couple of puffs before the capillary 14 runs dry. Therefore, the cartridge can also be used when it is turned around.

[0118] Fig. 4 shows a schematic perspective view of an inner shell 28 with its outer main surface 28B. The outer main surface 28B comprises protrusions in the form of ribs 36. These protrusions 36 may contact the inner main surface of the outer shell for maintaining a constant distance between the inner shell and the outer shell for forming the capillary. The flow of the aerosol-forming liquid in between the passages 28D of the outer main surface 28B between adjacent protrusions 36 is indicated by the arrow denoted 38. The outer main surface 28B of the inner shell 28 can comprise regions 28C which are completely free of the protrusions. Fig. 5A shows a schematic cross-sectional view of another embodiment of the cartridge 10. The air inlet 12 configured for allowing air to enter the liquid storage portion includes a second air inlet end 12C protruding into the interior of the liquid storage portion. The air inlet furthermore includes an opposing first air inlet end 12B which is located near or adjacent to the housing of the cartridge. The second air inlet end may be covered with a perforated membrane 40. The perforations 40A in the perforated membrane 40 allow the entry of air into the interior of the liquid storage portion. The perforated membrane 40 may bulge owing to negative pressure generated in the liquid storage portion when consuming the aerosol-forming liquid. The perforated membrane 40 may additionally reduce or avoid the leakage of aerosolforming liquid out of the liquid storage portion, in particular when the replaceable cartridge 10 is turned around.

[0119] Fig. 5B depicts a schematic cross-sectional view of another embodiment of the cartridge, wherein in contrast to the cartridge of Fig. 5A the first air inlet end 12B and not the second air inlet end 12C is covered with the perforated membrane 40. The perforated membrane 40 may contact parts of the housing of the cartridge. The perforated membrane 40 may be mounted to parts of the housing of the cartridge, wherein the parts are adjacent to the first air inlet end. The perforated membrane 40 may completely cover the first air inlet end of the air inlet. Air enters the air inlet 12 through the perforations 40A of the perforated membrane 40. When the aerosol-forming liquid is transported through the capillary during operation of the cartridge, negative pressure might build up in the liquid storage portion. This negative pressure may cause perforated membrane 42 bulge into the interior of the air inlet.

[0120] Fig. 6A depicts a schematic cross-sectional view of an aerosol-generating device 42. The aerosol-generating device 42 includes a cavity 56 for receiving the replaceable cartridge 10. At or near the cavity 56 a connector element 48 is located. The connector element 48 comprises a conduit 50 for conveying aerosol-forming liquid from the cartridge and a susceptor element 46 for inductively heating the aerosol-forming liquid conveyed in the conduit 50. The susceptor element 46 at least partially circumscribes the conduit 50. The aerosol-generating device 42 furthermore includes control circuitry 52 for controlling the operation of the aerosolgenerating device, in particular for controlling the induction coil 60 which is configured for heating the susceptor element 46. The aerosol-generating device 42 furthermore includes an energy source 54, such as a battery. Instead of a susceptor element 46, the connector element may include filaments for conveying the aerosol-forming liquid out of the cartridge through the capillary 14. The filaments may be inductively heatable, for example by being at least partly made of an inductively heatable material (filaments not shown in Fig. 6A). The aerosolgenerating device 42 includes a mouthpiece 44 which also serves as an aerosol-forming chamber. The mouthpiece 44 includes an air outlet 44A for a user to inhale aerosol generated by evaporating the aerosol-forming liquid. Fig. 6B depicts a schematic cross-sectional view of an aerosol-generating system 62 which includes the aerosol-generating device 42 shown in Fig. 6A and a replaceable cartridge 10 in accordance with the present invention. As it can be seen, the aerosol-forming liquid 20A is conveyed out of the cartridge 10 via the action of the capillary force in the capillary 14 and is heated either by the susceptor element 46 or by inductively heatable filaments being present in the conduit of the connector element (filaments not shown in Fig. 6B). The aerosol-forming liquid is evaporated via inductive heating and is subsequently transported through the mouthpiece 44 to the air outlet 44A as indicated by the dashed arrows 64.

Claims

CLAIMS1. A replaceable cartridge configured for being detachably connectable to an aerosol-generating device comprising: a liquid storage portion for storing an aerosol-forming liquid, the liquid storage portion comprising a liquid outlet for directing the aerosol-forming liquid out of the liquid storage portion, and a capillary being in fluid communication with the liquid storage portion and the liquid outlet, and an air inlet configured for allowing air to enter the liquid storage portion, wherein the air inlet protrudes into the interior of the liquid storage portion, furthermore comprising a housing enclosing the liquid storage portion, wherein the air inlet extends from the housing into the interior of the liquid storage portion and wherein a cross sectional area of the air inlet at the housing is larger than a cross-sectional area of the air inlet in the interior of the liquid storage portion.

2. The replaceable cartridge of the preceding claim, wherein the cross-sectional area of the air inlet decreases from the housing towards the interior of the liquid storage portion.

3. The replaceable cartridge of any of the preceding claims, wherein the air inlet is funnel-shaped.

4. The replaceable cartridge of any of the preceding claims, wherein the capillary comprises a first end and an opposing second end, wherein the air inlet is located at or adjacent to the first end and wherein the liquid outlet is located at or adjacent to the second end.

5. The replaceable cartridge of the preceding claim, wherein one or both, the capillary is in fluid communication with the liquid storage portion at the first end and the capillary is in fluid communication with the liquid outlet at the second end.

6. The replaceable cartridge of any of the preceding claims, wherein the air inlet comprises a sidewall extending from the housing into the interior of the liquid storage portion, preferably wherein a height of the sidewall in the interior is higher than a maximum height of the aerosol-forming liquid in the liquid storage portion.

7. The replaceable cartridge of the preceding claim, wherein a distance between opposing sidewalls of the air inlet is larger than a maximum cross-sectional width of the capillary.

8. The replaceable cartridge of any of the preceding claims, wherein the housing comprises an outer shell and an inner shell, wherein the inner shell is located in the interior of the cartridge and wherein the capillary is formed between the outer shell and the inner shell.

9. The replaceable cartridge of the preceding claim, further dependent on claim 6, wherein a maximum distance between the outer shell and the inner shell is smaller than a distance between opposing sidewalls of the air inlet.

10. The replaceable cartridge of any of the preceding claims 8 or 9, wherein the overall geometric shape of the inner shell conforms to the overall geometric shape of the outer shell, preferably wherein the outer shell and the inner shell have a tubular or cylindrical shape.

11. The replaceable cartridge of any of the preceding claims, wherein the liquid outlet comprises a liquid-conveying susceptor configured for directing the aerosol-forming liquid out of the liquid storage portion and configured for inductively heating the aerosol-forming liquid during operation of the aerosol-generating device.

12. The replaceable cartridge of any of the preceding claims, wherein the air inlet comprises a first air inlet end and an opposing second air inlet end, wherein the second air inlet end is located in the interior of the liquid storage portion and wherein one or both the first and the second air inlet end are covered with a perforated membrane, preferably wherein the first air inlet end is covered with the perforated membrane.

13. An aerosol-generating system comprising a replaceable cartridge of any of the preceding claims 1 to 12, and an aerosol-generating device being configured to be detachably connectable to the cartridge.

14. The aerosol-generating system of the preceding claim, wherein the aerosolgenerating device comprises a heating element configured for heating the aerosol-forming liquid, preferably wherein the aerosol-generating device comprises an induction coil configured for heating the liquid-conveying susceptor.

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