CN116981370A

CN116981370A - Aerosol generating device with venting means

Info

Publication number: CN116981370A
Application number: CN202280020787.0A
Authority: CN
Inventors: T·H·马塔嫩; 欧思杰; 宗启申; 杨咏道
Original assignee: Philip Morris Products SA
Current assignee: Philip Morris Products SA
Priority date: 2021-03-19
Filing date: 2022-03-18
Publication date: 2023-10-31
Also published as: KR20230160313A; WO2022195101A1; BR112023018098A2; IL305874A; EP4307941A1; JP2024510643A; US20240148071A1

Abstract

The invention relates to an aerosol-generating device (1), comprising: a heating chamber adapted to receive an aerosol-generating article; a heating element (5); a sealed housing compartment (8); -a venting means (10) adapted to allow a flow of gas from the sealed housing compartment (8) to the outside of the aerosol-generating device (1) to compensate for thermal expansion of the gas inside the housing compartment (8) due to a heating operation of the heating element (5). The invention also relates to a method for operating an aerosol-generating system and to the use of a ventilation membrane (10) in an aerosol-generating device (1).

Description

Aerosol generating device with venting means

Technical Field

The present invention relates to an aerosol-generating device having a sealed housing compartment. The invention also relates to a method for operating an aerosol-generating system and to the use of a vent membrane in an aerosol-generating device.

Background

One type of aerosol-generating system is an electrically operated smoking system. Known hand-held electrically operated smoking systems typically comprise an aerosol-generating device comprising a battery, control electronics and an electric heater for heating an aerosol-generating article specifically designed for use with the aerosol-generating device. In some examples, the aerosol-generating article comprises an aerosol-forming substrate, such as a tobacco rod or tobacco rod, and upon insertion of the aerosol-generating article into the aerosol-generating device, a heater contained within the aerosol-generating device is inserted into or around the aerosol-forming substrate. In an alternative electrically operated smoking system, the aerosol-generating article may comprise a capsule comprising an aerosol-forming substrate, for example loose tobacco.

Disclosure of Invention

According to a first aspect of the present invention there is provided an aerosol-generating device comprising: a heating chamber adapted to receive an aerosol-generating article; a heating element; sealing the housing compartment; and a venting means adapted to allow gas to flow from the sealed housing compartment to the exterior of the aerosol-generating device to compensate for thermal expansion of the gas inside the housing compartment due to a heating operation of the heating element.

The transverse direction of the aerosol-generating device may be perpendicular to the longitudinal direction of the aerosol-generating device. The longitudinal direction may be the main direction of extension of the aerosol-generating device, i.e. the direction in which the aerosol-generating device has its maximum length. In the upright orientation of the aerosol-generating device, the longitudinal direction is the height direction and the transverse direction may be the horizontal direction. The transverse direction may be perpendicular to the width direction of the aerosol-generating device. Any indications below regarding "upper" and "lower" are in the height direction relative to the longitudinal direction.

The aerosol-generating article may be inserted into the heating chamber of the aerosol-generating device in the longitudinal direction such that the aerosol-generating article is at least partially arranged in the heating chamber. When the aerosol-generating article abuts against the stop element or an end surface of the heating chamber, the mouth end portion of the aerosol-generating article may protrude from the heating chamber in the longitudinal direction.

The housing compartment is sealed against dust ingress or against ingress of dust and water. The housing compartment may comprise a floor. The bottom plate may sealingly close the underside of the housing compartment. At least one of the heating element, the control electronics and the battery is arranged in the housing compartment.

The heating element may be disposed in or near the sealed housing compartment.

The heating element may be a resistive heating element or an inductive heating element, such as an inductor (e.g. a coil). Control electronics may be provided which are adapted to control the heating element to rapidly heat the aerosol-generating article in the heating chamber. The heating element and control electronics of the aerosol-generating device may be modified such that the temperature of the heating element is between 70 degrees celsius and 130 degrees celsius, or between 80 degrees celsius and 120 degrees celsius, or between 80 degrees celsius and 100 degrees celsius. The heating element and the control electronics may be modified such that the heating time for heating the heating element from ambient temperature to at least 80 degrees celsius is less than 5 seconds or less than 3 seconds.

The heating element and control electronics of the aerosol-generating device may be modified such that the aerosol-generating article is heated to a temperature between 70 degrees celsius and 130 degrees celsius, or between 80 degrees celsius and 120 degrees celsius, or between 80 degrees celsius and 100 degrees celsius. The heating element and the control electronics may be modified such that the heating time for heating the aerosol-generating article from ambient temperature to at least 80 degrees celsius is less than 5 seconds or less than 3 seconds.

The heating element and control electronics of the aerosol-generating device may be modified such that the aerosol-generating article is heated to a temperature between 250 degrees celsius and 400 degrees celsius, or between 300 degrees celsius and 350 degrees celsius. The heating element and the control electronics may be modified such that the heating time for the aerosol-generating article from ambient temperature to at least 300 degrees celsius is less than 60 seconds or less than 30 seconds.

The heating element and the control electronics may be adapted to heat in several successive heating cycles during consumption of one aerosol-generating article, wherein the temperature variation in the heating element is at least 10 degrees celsius or at least 20 degrees celsius.

Pressure may build up in the housing compartment due to temperature variations of the gas in the housing compartment. The venting means allows gas to flow from the sealed housing compartment to the outside to prevent excessive pressure in the sealed housing compartment. The venting means may be adapted to allow an inflow of gas from the outside into the sealed housing compartment to compensate for negative, sub-ambient pressure during cooling or during low temperature phases during aerosol generation.

The venting means may be permeable to gas and impermeable to water. Thus, the aerosol-generating device may be waterproof.

The aeration device may have a water entry pressure of at least 5 kilopascals, preferably at least 10 kilopascals, in particular about 12 kilopascals. This makes the aerosol-generating device more and more waterproof.

The vent may have an airflow capacity of 3000 to 7000 ml/cm min at 7 kpa, preferably 5000 to 5200 ml/cm min at 7 kpa. The airflow capacity allows for quick compensation of temperature variations in the aerosol-generating device.

The venting means may be available in a temperature range of-40 degrees celsius to 150 degrees celsius. In another embodiment, the venting device may be available at a temperature in the range of-20 degrees celsius to 90 degrees celsius. The vent may have the aforementioned airflow capacity throughout this temperature range. The aerator may have the aforementioned water entry pressure throughout this temperature range.

The venting means may comprise a membrane. The membrane may be modified so that gas may flow through the membrane. The area of the membrane may define a possible gas flow. The membrane may be modified such that liquid, in particular water, cannot flow through the membrane.

The venting device may include a membrane having expanded polytetrafluoroethylene. This allows a waterproof, gas permeable membrane to be preferably achieved.

The venting means may comprise expanded polytetrafluoroethylene applied to the backing layer. The backing layer may be permeable to both gas and water and may provide structural stability.

The venting device may include a hydrophobic and oleophobic membrane. This enables the interior of the sealed housing compartment to be protected from polar liquids (e.g. water) and non-polar liquids (e.g. oil).

The venting means may comprise an inert and UV resistant membrane. Thus, the durability of the separator may be improved when the separator is in contact with potentially reactive substances from the environment.

The membrane may be connected to a carrier substrate having a central opening with a dimension of at least 0.5 square millimeters, at least 1 square millimeter, or at least 2 square millimeters. The carrier substrate may be in the form of a flat rectangle with a central opening. Alternatively, the carrier substrate may be in the form of a flat circle with a central opening.

The carrier substrate may improve the sealing properties of the membrane and the fluid tight connection of the membrane to the sealed housing compartment. The size of the openings determines the potential gas flow at a given relative pressure on opposite sides of the diaphragm.

The carrier substrate may be a double sided adhesive layer, thereby connecting the membrane to the housing compartment. Thus, dual functions of sealing and attachment are provided.

The membrane may have a thickness of 0.05 to 0.5 mm, preferably 0.1 to 0.2 mm, in particular about 0.15 mm. This thickness range provides a structurally stable but substantially permeable membrane.

The membrane is arranged overlapping over the opening of the housing compartment. This allows sealing the opening of the housing compartment while still allowing venting through the membrane. The opening may be a through hole in a wall of the housing compartment.

The vent may include an opening in the housing compartment and a channel extending into the housing compartment wall. The housing compartment wall may be formed by a floor. The extending direction of the passage may be in a direction different from the opening direction of the housing opening. Thus, the venting device, and in particular the membrane of the venting device, may be protected from contact with external objects. The fluid flow may be improved because the gas flow may be less constrained by such geometry than the liquid flow. The channel and opening geometry may be particularly preferred for polar liquids (e.g. water) to prevent the polar liquid from reaching the membrane due to the surface tension of the polar liquid. The direction of extension of the channel may be at an angle of at least 45 degrees, preferably at least 60 degrees, to the opening direction of the housing opening, and in particular perpendicular to the opening direction of the housing opening.

The cross-sectional area of the housing opening may be greater than the cross-sectional area of the passage. Thus, a sufficiently high flow through the opening in the housing can be obtained, despite the membrane being arranged therein.

The channels may have a cross-sectional area between 0.5 square millimeters and 2 square millimeters. This provides a sufficient gas flow but makes it difficult for liquid to enter the channel.

The channel may be a recess extending into the housing compartment wall. Thus, the gas may flow out of the channel at any point along its length. Alternatively, the channel may be a closed channel with walls on all sides in the flow direction.

The channels may connect the vent to recessed areas in the housing compartment walls. The recessed area may have a larger opening to the outside than the channel, thereby facilitating gas outflow.

The bottom plate may be fixed by means of screws. The placement of the venting means close to the screw enables the venting means to be provided in areas of the aerosol-generating device which are less likely to deform during normal handling, in particular due to the tension of the screw. Thus, involuntary relative movement of the components of the aerosol-generating device is less likely to block the passage or opening of the vent.

The screw head may be disposed in the recessed area. Thus, the recess required for the screw head to accommodate may provide a dual function for the ventilation gas flow.

The electrical connector may be disposed in the recessed area. Thus, the electrical connector opening may be used for ventilation.

The cover panel may be arranged outside the vent, wherein a gap is provided between the cover panel and the vent such that the vent is arranged at a distance of 0.3 mm to 1 mm from the cover panel. Thus, a gas flow communication between the cover panel and the ventilation device is possible. Furthermore, the venting device may be protected from mechanical damage.

The bottom plate may include protruding sidewalls in a lateral direction. The cover panel may be secured to the interior of the protruding sidewall. The cover panel may be clamped in the base panel or secured to the base panel by means of an adhesive.

The sealed housing compartment may include electronic components. Sealing the housing compartment may protect the electronic components from liquid.

The sealed housing compartment includes a button adapted to interact with control electronics in the sealed housing compartment, wherein movement of the button changes an interior volume of the sealed housing compartment. Since the housing compartment is sealed, temperature changes change the pressure inside the housing compartment, which can change the position or response force of the button. The venting means allows the pressure inside the sealed housing compartment not to change significantly even during heating by means of the heating element and ensures that the button can be operated with the same tactile properties at any time. The button may be overmolded with an elastomeric material such that sealing of the housing compartment is achieved. The button may be attached with a double sided adhesive tape such that sealing of the housing compartment is achieved.

The venting means may comprise a membrane arranged on the outside of the housing compartment wall, in particular in the form of a floor.

The venting means may comprise a membrane arranged on the inside of the housing compartment wall, in particular in the form of a floor.

The diaphragm may be disposed in a recess in a compartment wall of the housing. This allows the membrane to be protected. The diaphragm may deform due to pressure.

According to a second aspect of the present invention, there is provided an aerosol-generating system according to any of the embodiments described herein comprising an aerosol-generating device according to the first aspect of the present invention. The aerosol-generating system further comprises an aerosol-generating article comprising an aerosol-forming substrate. As used herein, the term "aerosol-generating article" refers to an article comprising an aerosol-forming substrate that upon heating releases volatile compounds that can form an aerosol.

The aerosol-forming substrate may comprise a tobacco rod. The tobacco rod may include one or more of the following: a powder, granule, pellet, chip, strand, ribbon or sheet comprising one or more of tobacco leaves, pieces of tobacco ribs, reconstituted tobacco, homogenized tobacco, extruded tobacco and expanded tobacco. Optionally, the tobacco rod may contain additional tobacco or non-tobacco volatile flavour compounds that are released upon heating of the tobacco rod. Optionally, the tobacco rod may also comprise a pouch, for example comprising additional tobacco or non-tobacco volatile flavour compounds. Such capsules may melt during heating of the tobacco rod. Alternatively or additionally, such capsules may be crushed before, during or after heating the tobacco rod.

Where the tobacco rod comprises homogenized tobacco material, the homogenized tobacco material may be formed by agglomerating particulate tobacco. The homogenized tobacco material may be in the form of a sheet. The homogenized tobacco material may have an aerosol former content of greater than 5 percent on a dry weight basis. The homogenized tobacco material may alternatively have an aerosol former content of between 5 wt.% and 30 wt.% on a dry weight basis. A sheet of homogenized tobacco material may be formed from particulate tobacco obtained by agglomerating one or both of tobacco lamina and tobacco leaf stems by grinding or otherwise pulverizing; alternatively or additionally, the sheet of homogenized tobacco material may include one or more of tobacco dust, tobacco scraps, and other particulate tobacco byproducts formed during, for example, handling, processing, and transporting tobacco. The sheet of homogenized tobacco material may include one or more intrinsic binders (i.e., tobacco endogenous binders), one or more extrinsic binders (i.e., tobacco exogenous binders), or a combination thereof to help agglomerate the particulate tobacco. Alternatively or additionally, the sheet of homogenized tobacco material may include other additives including, but not limited to, tobacco and non-tobacco fibers, aerosol formers, humectants, plasticizers, flavorants, fillers, aqueous and non-aqueous solvents, and combinations thereof. The sheet of homogenized tobacco material is preferably formed by a casting process of the type generally comprising: casting a slurry comprising particulate tobacco and one or more binders onto a conveyor belt or other support surface; drying the cast slurry to form a sheet of homogenized tobacco material; and removing the sheet of homogenized tobacco material from the support surface.

The aerosol-generating article may have an overall length of between about 30 millimeters and about 100 millimeters. The aerosol-generating article may have an outer diameter of between about 5 mm and about 13 mm.

The aerosol-generating article may comprise a mouthpiece positioned downstream of the tobacco rod. The mouthpiece may be located at the downstream end of the aerosol-generating article. The mouthpiece may be a cellulose acetate filter segment. Preferably, the mouthpiece has a length of about 7 mm, but may have a length of between about 5 mm and about 10 mm.

The tobacco rod may have a length of about 10 millimeters. The tobacco rod may have a length of about 12 millimeters.

The tobacco rod may have a diameter of between about 5 mm and about 12 mm.

In a preferred embodiment, the aerosol-generating article has an overall length of between about 40 mm and about 50 mm. Preferably, the aerosol-generating article has an overall length of about 45 mm. Preferably, the aerosol-generating article has an outer diameter of about 7.2 mm.

According to a third aspect of the present invention, there is provided a method for operating an aerosol-generating system, comprising the steps of: inserting an aerosol-generating article into a heating chamber of an aerosol-generating device; heating an aerosol-generating article to generate an aerosol; the heated gas is allowed to flow from the sealed housing compartment of the aerosol-generating device to the outside through the venting means. Thus, the pressure inside the sealed housing compartment does not change significantly despite the heating. The interior of the sealed housing compartment may be at substantially ambient pressure despite the heating.

Water can be prevented from flowing from the outside into the housing compartment through the venting means. Thus, the control electronics inside the sealed housing compartment are protected.

Ventilation gas may flow through the recess for the screw head. Thus, the volume between the wall of the screw head recess and the screw head may serve as a vent channel or outlet.

Ventilation gas may flow through the electrical connector openings. Thus, the electrical connector opening may serve as a vent outlet.

The ventilation gas may flow under the cover panel. Thus, the ventilation device can be protected. The flow of heated gas may be distributed to one or several outlet locations in or at the cover panel.

According to a fourth aspect of the present invention there is provided the use of a vent membrane in an aerosol-generating device to compensate for thermal expansion of a gas due to heat generated in a heating chamber receiving an aerosol-generating article. Thus, it is possible to prevent pressure from accumulating in the aerosol-generating device due to thermal expansion of the gas in the aerosol-generating device.

The aerosol-generating device according to the first aspect of the invention may be used in any embodiment thereof according to the method of the third aspect of the invention. The method according to the third aspect of the invention may be performed in any embodiment thereof by using the aerosol-generating device according to the first aspect of the invention or in any embodiment thereof by using the system according to the second aspect of the invention. The use of the vent membrane according to the fourth aspect of the invention may be performed with the aerosol-generating device according to the first aspect of the invention in any embodiment thereof and by using the method steps of the method according to the third aspect of the invention in any embodiment thereof.

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.

Example Ex1: an aerosol-generating device comprising: a heating chamber adapted to receive an aerosol-generating article; a heating element; sealing the housing compartment; and a venting means adapted to allow gas to flow from the sealed housing compartment to the exterior of the aerosol-generating device to compensate for thermal expansion of the gas inside the housing compartment due to a heating operation of the heating element.

Example Ex2: the aerosol-generating device of example Ex1, wherein the venting device is permeable to gas and impermeable to water.

Example Ex3: the aerosol-generating device of example Ex1 or example Ex2, wherein the venting device has a water entry pressure of at least 5 kilopascals, preferably at least 10 kilopascals, in particular about 12 kilopascals.

Example Ex4: an aerosol-generating device according to any of examples Ex1 to Ex3, wherein the venting device has an airflow capacity of 3000 to 7000 ml/cm min at 7 kpa, preferably 5000 to 5200 ml/cm min at 7 kpa.

Example Ex5: the aerosol-generating device of any of examples Ex1 to Ex4, wherein the venting device is available in a temperature range of-40 degrees celsius to 150 degrees celsius.

Example Ex6: the aerosol-generating device of any of examples Ex 1-Ex 5, wherein the venting device comprises a septum.

Example Ex7: the aerosol-generating device of any of examples Ex 1-Ex 6, wherein the venting device comprises a membrane comprising expanded polytetrafluoroethylene.

Example Ex8: the aerosol-generating device of any of examples Ex 1-Ex 7, wherein the venting device comprises expanded polytetrafluoroethylene applied on a backing layer.

Example Ex9: the aerosol-generating device of any of examples Ex 1-Ex 8, wherein the venting device comprises a hydrophobic and oleophobic membrane.

Example Ex10: the aerosol-generating device of any of examples Ex 1-Ex 9, wherein the venting device comprises an inert and UV resistant membrane.

Example Ex11: an aerosol-generating device according to any of examples Ex1 to Ex10, wherein the venting device comprises a membrane, wherein the membrane is connected to a carrier substrate having a central opening with a dimension of at least 0.5 square millimeters, at least 1 square millimeter, or at least 2 square millimeters.

Example Ex12: the aerosol-generating device of example Ex11, wherein the carrier substrate is a double-sided adhesive layer, connecting the membrane to the housing compartment.

Example Ex13: the aerosol-generating device according to any of examples Ex6 to Ex12, wherein the membrane has a thickness of 0.05 to 0.5 mm, preferably 0.1 to 0.2 mm, in particular about 0.15 mm.

Example Ex14: an aerosol-generating device according to any of examples Ex6 to Ex13, wherein the membrane is arranged overlapping over the opening of the housing compartment.

Example Ex15: an aerosol-generating device according to any of examples Ex1 to Ex14, wherein the venting means comprises a housing opening in the housing compartment and a channel extending in a housing compartment wall, wherein the direction of extension of the channel is in a direction different from the opening direction of the housing opening.

Example Ex16: the aerosol-generating device of example Ex15, wherein the cross-sectional area of the housing opening is greater than the cross-sectional area of the channel.

Example Ex17: the aerosol-generating device of example Ex15 or Ex16, wherein the channel has a cross-sectional area between 0.5 square millimeters and 2 square millimeters.

Example Ex18: the aerosol-generating device of any of examples Ex15 to Ex17, wherein the channel is a recess extending in a housing compartment wall.

Example Ex19: an aerosol-generating device according to any of examples Ex15 to Ex18, wherein the channel connects the venting device to a recessed area in the housing compartment wall.

Example Ex20: the aerosol-generating device of example Ex19, wherein a screw head is disposed in the recessed region.

Example Ex21: the aerosol-generating device of example Ex19 or Ex20, wherein an electrical connector is arranged in the recessed area.

Example Ex22: an aerosol-generating device according to any of examples Ex1 to Ex21, wherein a cover panel is arranged outside the vent, wherein a gap is provided between the cover panel and the vent such that the vent is arranged at a distance of 0.3 to 1 mm from the cover panel.

Example Ex23: the aerosol-generating device of any of examples Ex1 to Ex22, wherein the sealed housing compartment comprises electronic components.

Example Ex24: the aerosol-generating device according to any of examples Ex1 to Ex23, wherein the sealed housing compartment comprises a button adapted to interact with control electronics in the sealed housing compartment, wherein movement of the button changes an internal volume of the sealed housing compartment.

Example Ex25: an aerosol-generating device according to any of examples Ex1 to Ex24, wherein the venting device comprises a membrane arranged on the outside of the housing compartment wall.

Example Ex26: an aerosol-generating device according to any of examples Ex1 to Ex25, wherein the venting device comprises a membrane arranged on the inside of the housing compartment wall.

Example Ex27: the aerosol-generating device of examples Ex25 to Ex26, wherein the septum is disposed in a recess in a wall of the housing compartment.

Example Ex28: a method for operating an aerosol-generating system, comprising the steps of:

inserting the aerosol-generating article into a heating chamber of an aerosol-generating device,

heating the aerosol-generating article to generate an aerosol,

-allowing a flow of heated gas from the sealed housing compartment of the aerosol-generating device to the outside through the venting means.

Example Ex29: the method of example Ex28, further comprising the steps of: water is prevented from flowing from the outside into the housing compartment through the venting means.

Example Ex30: the method of example Ex28 or Ex29, wherein the venting gas flows through a recess for the screw head.

Example Ex31: the method of any one of examples Ex 28-Ex 30, wherein the ventilation gas flows through an electrical connector opening.

Example Ex32: the method of any of examples Ex 28-Ex 31, wherein the ventilation gas flows under a cover panel.

Example Ex33: use of a vent membrane in an aerosol-generating device for compensating for thermal expansion of a gas due to heat generated in a heating chamber receiving an aerosol-generating article.

Example Ex34: an aerosol-generating system comprising an aerosol-generating device according to any of the preceding examples Ex1 to Ex26 and an aerosol-generating article, wherein the aerosol-generating article comprises an aerosol-forming substrate.

Drawings

Several examples will now be further described with reference to the accompanying drawings.

Fig. 1 shows a perspective view of an aerosol-generating device.

Fig. 2 shows a cross section through the aerosol-generating device of fig. 1.

Fig. 3 shows a perspective view of the aerosol-generating device of fig. 1 from below.

Fig. 4 shows a partial perspective view from below of the aerosol-generating device of fig. 1 without the cover panel.

Fig. 5 shows a partial cross-sectional view of the lower region of the aerosol-generating device of fig. 1.

Fig. 6 shows a partial cross-sectional view of a lower region of the aerosol-generating device of fig. 1 with the inner holder removed.

Fig. 7 shows a partial cross-sectional view of the lower region of the aerosol-generating device of fig. 1.

Fig. 8 shows a partial perspective view from below of an aerosol-generating device according to a second embodiment of the invention without a cover panel.

Fig. 9 shows a perspective view of the base plate in the second embodiment.

Detailed Description

In fig. 1 an aerosol-generating device 1 according to a first embodiment of the invention is shown in an upright orientation. The aerosol-generating device 1 comprises a housing 2 and a cover element 3, which is arranged slidably on the housing 2 in a transverse direction 100. The housing 2 extends mainly in the longitudinal height direction 200 and has its relatively smallest extension in the width direction 300. The cover element 3 is shown in fig. 1 and 2 in a closed position covering the aperture of the heating chamber 4.

The heating chamber 4 is adapted to receive a strip-shaped aerosol-generating article and to heat said strip-shaped aerosol-generating article by means of the heating element 5 when the cover element 3 is in the open position. The heating element 5 is an induction coil module adapted to heat a susceptor, which may be part of a strip-shaped aerosol-generating article. The heating element 5, the control electronics 6 and the battery 7 are arranged in a housing compartment 8 of the housing 2.

The housing compartment 8 is sealed to prevent water or dust from entering the housing compartment 8. The housing compartment 8 may comprise a button 9 that is over-molded to be sealed.

When the aerosol-generating article is heated, an aerosol is generated, which may be consumed in a similar manner to a cigarette, with the mouth end of the strip protruding from the heating chamber. For a favorable consumer experience, adequate and rapid aerosol delivery is desirable. This requires a sufficient and rapid heating of the aerosol-generating article. Thus, the heating of the aerosol-generating article is performed at a relatively high power. This means that not only the aerosol-generating article, but also the heating element 5 as well as the control electronics 6 and the battery 7 will generate heat and heat the gas (i.e. air) inside the housing compartment 8.

During aerosol generation, the gas inside the housing compartment 8 is heated and rapidly expands. This will increase the pressure inside the sealed housing compartment 8 and this pressure will also act against the inside of the button 9, changing the appearance of the button 9 or the user activation experience.

In order to avoid such a pressure increase inside the housing compartment 8, a venting means 10 is provided in the lower region of the aerosol-generating device 1. The venting means 10 is arranged in close proximity to the electrical connector opening 11.

The venting means 10 is at least partially arranged in the floor 12 of the housing compartment 8. The bottom plate 12 is connected by means of screws 13 to close the housing compartment 8. The cover panel 14 is connected to the base plate and covers the screws 13. A gap 15 is provided between the base panel 12 and the lid panel 14. The gap 15 enables gas to flow between the base panel 12 and the lid panel 14. The base plate 12 includes protruding side walls 16, as can be seen in fig. 4. The cover panel 14 is connected to the protruding side wall 16 by means of an adhesive.

In fig. 3, an electrical connector (e.g., a USB-C connector) is disposed in the electrical connector opening 11. The passage 17 of the venting device 10 opens into the electrical connector opening 11. The channels 17 allow gas to flow through the ventilation device 10.

In fig. 4, the cover panel 14 is removed so that the channel 17 is fully visible. The channel 17 opens into an opening 18 in the base plate 12.

The channels 17 extend in the width direction 300 and the openings 18 extend in the transverse direction 100. In order to achieve a constant wall thickness of the bottom plate 12, a recessed area 19 is provided in the bottom plate 12, next to the opening 18 and the channel 17 of the venting device 10. This facilitates the creation of the bottom plate by means of injection moulding and enables an advantageous geometry of the channels 17 and openings 18.

As shown in fig. 5, an optional spacer 20 is disposed on the interior of the base plate 12. The spacer 20 may be elastic. The base plate 12 comprises a projection 21 which engages into a recess 22 of the spacer 20. The spacer 20 is arranged between and in contact with the holder 23 and the base plate 12. In particular, the holder 23 may be part of or connected to a battery holder 24. The spacer 20 has a central spacer opening 25 and the retainer 23 has a central retainer opening 26. The spacer opening 25 and the holder opening 26 extend in the lateral direction and are substantially aligned. A membrane 27 is arranged between the holder 23 and the spacer 20 such that the membrane covers the openings 25, 26. The membrane 27 may be connected to a carrier substrate 28. The carrier substrate 28 may be a double sided adhesive tape. The carrier substrate 28 may connect the membrane 27 to the holder 23. The carrier substrate 28 has a central opening 29 that is substantially aligned with the openings 25 and 26 of the spacer 20 and the holder 23. The membrane 27 allows gas flow but prevents liquid flow.

In fig. 8, a second embodiment of an aerosol-generating device 1 according to the invention is shown. For the purpose of illustration, the bottom plate 12 corresponding to the bottom plate 12 of the first embodiment is removed. The venting means 30 is arranged between the recess 31 for the head 32 of the screw 13 and the electrical connector opening 11. The venting means 30 comprises a first channel 33 leading to the electrical connector opening 11. The venting means 30 comprises a second channel 34 leading to the screw recess 31. Thus, during venting, air from the interior of the housing compartment 8 can flow through the channels 33, 34 to the electrical connector opening 11 and the screw recess 31, and then to the outside. The venting device 30 comprises a membrane 35 that is permeable to gas but impermeable to liquid. The membrane 35 is arranged on a carrier substrate 36, which may be in the form of a double sided adhesive tape connecting the membrane 35 to the base plate 12. In the second embodiment, the diaphragm 35 is arranged on the outside of the bottom plate 12, whereas in the first embodiment, the diaphragm is arranged on the inside of the button plate 12.

The bottom plate 12 of the second embodiment is shown in isolation in fig. 9. A recess 37 is provided for receiving the membrane 35 and the carrier substrate 36. The membrane 35 covers an opening 38, which is centrally arranged in the recess 37.

In an embodiment of the method according to the invention, the aerosol-generating rod is inserted into the heating chamber 4 and heated therein. The gas inside the housing compartment 8 of the aerosol-generating device 1 is heated and thus the pressure is increased by thermal expansion of said gas. As a result of the provision of the ventilation means 10 or 30, the gas will flow through the membrane 35 and the channels 17 in the first embodiment or the membrane 35 and the channels 33 and 34 in the second embodiment and then to the outside. Thus, to compensate for the pressure difference of the heat generation, gas may flow into and out of the housing compartment 8. However, due to the arrangement of the channels 17, 33, 34 and the openings 18, 28 of the ventilation means 10, 30, and due to the membrane 27, 25, water or dust is prevented from being sucked into the aerosol-generating device.

The channels 17, 33, 34 may be in the form of recesses in the base plate 12, forming tubular channels when closed by means of the lid panel 14. Preferably, the cover panel is arranged at a distance from the vent membrane such that a gap is provided between the cover panel 14 and the vent 10, 30.

The ventilation device 10 may be centrally located along the transverse direction 100 of the aerosol-generating device 1. The openings 18, 28 in the bottom plate 12 may be in the form of through holes. The gap 15 between the base panel 12 and the lid panel 14 has a height that is expected to potentially deform the diaphragm 35 due to pressure. The ventilation air in the screw recess 31 can escape to the outside along the flow path between the cover panel 14 and the side wall 16 of the base panel 12.

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 a±10% 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 device comprising:

a heating chamber adapted to receive an aerosol-generating article,

the heating element is arranged such that,

the housing compartment is sealed off and,

a venting means adapted to allow gas to flow from the sealed housing compartment to the exterior of the aerosol-generating device to compensate for thermal expansion of the gas inside the housing compartment due to a heating operation of the heating element.

2. An aerosol-generating device according to claim 1, wherein the venting device has a water entry pressure of at least 5 kpa, preferably at least 10 kpa, in particular about 12 kpa.

3. An aerosol-generating device according to claim 1 or 2, wherein the venting device has an airflow capacity of 3000 to 7000 ml/cm min at 7 kpa, preferably 5000 to 5200 ml/cm min at 7 kpa.

4. An aerosol-generating device according to any of the preceding claims, wherein the venting means comprises expanded polytetrafluoroethylene applied on a backing layer.

5. An aerosol-generating device according to any of the preceding claims, wherein the venting device comprises a membrane, wherein the membrane is connected to a carrier substrate having a central opening of a size of at least 0.5 square millimeters, at least 1 square millimeter or at least 2 square millimeters.

6. An aerosol-generating device according to claim 5, wherein the membrane has a thickness of 0.05 to 0.5 mm, preferably 0.1 to 0.2 mm, in particular about 0.15 mm.

7. An aerosol-generating device according to any of the preceding claims, wherein the venting means comprises an opening in the housing compartment and a channel extending in the housing compartment wall, wherein the direction of extension of the channel is in a direction different from the direction of opening of the housing opening.

8. An aerosol-generating device according to claim 7, wherein the channel is a recess extending in a wall of the housing compartment.

9. An aerosol-generating device according to claim 7 or 8, wherein the channel connects the venting device to a recessed area in the housing compartment wall.

10. An aerosol-generating device according to claim 9, wherein a screw head is arranged in the recessed area.

11. An aerosol-generating device according to claim 9 or 10, wherein an electrical connector is arranged in the recessed area.

12. An aerosol-generating device according to any of the preceding claims, wherein a cover panel is arranged outside the venting device, wherein a gap is provided between the cover panel and the venting device.

13. An aerosol-generating device according to claim 12, wherein the ventilation means is arranged at a distance of 0.3 to 1 mm from the cover panel.

14. An aerosol-generating device according to any of the preceding claims, wherein the sealed housing compartment comprises a button adapted to interact with control electronics in the sealed housing compartment, wherein movement of the button changes the internal volume of the sealed housing compartment.

15. An aerosol-generating device according to any of claims 1 to 14, wherein the heating element is provided in the sealed housing compartment.

16. A method for operating an aerosol-generating system, comprising the steps of:

-heating the aerosol-generating article to generate an aerosol, and

17. Use of a vent membrane in an aerosol-generating device for compensating for thermal expansion of a gas due to heat generated in a heating chamber receiving an aerosol-generating article.

18. An aerosol-generating system comprising:

an aerosol-generating device according to any of claims 1 to 15, and

an aerosol-generating article comprising an aerosol-generating substrate.