Aerosol generating device equipped with ventilation means

Abstract

The present 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) and venting means (10) adapted to allow gas flow from the sealed housing compartment (8) to the exterior of the aerosol generating device (1) to compensate for thermal expansion inside the housing compartment (8) due to the heating action of the heating element (5). The present invention further relates to a method of operating an aerosol generating system and to the use of the venting membrane (10) in the aerosol generating device (1).

Description

[Technical field]

[0001] The present invention relates to an aerosol generating device having a sealed housing compartment. The present invention also relates to a method of operating an aerosol generating system and to the use of a vent membrane in an aerosol generating device. [Background technology]

[0002] One type of aerosol generating system is an electrically operated smoking system. Known handheld electrically operated smoking systems generally include an aerosol generating device that includes 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 embodiments, the aerosol generating article includes an aerosol-forming substrate, such as a tobacco rod or tobacco plug, and a heater housed within the aerosol generating device is inserted into or disposed around the aerosol-forming substrate when the aerosol generating article is inserted into the aerosol generating device. In an alternative electrically operated smoking system, the aerosol generating article may include a capsule that contains an aerosol-forming substrate, such as loose tobacco. Summary of the Invention

[0003] 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, a sealed housing compartment, and ventilation 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 inside the housing compartment due to heating action of the heating element.

[0004] 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 an upright orientation of the aerosol-generating device, the longitudinal direction is the height direction and the transverse direction may be horizontal. The transverse direction may be perpendicular to the width direction of the aerosol-generating device. The designations below regarding "upper" and "lower" are relative to the longitudinal direction, which is the height direction.

[0005] The aerosol-generating article may be inserted longitudinally into a heating chamber of an aerosol generating device such that the aerosol-generating article is at least partially disposed within the heating chamber, and when the aerosol-generating article abuts a stop element or end face of the heating chamber, an oral end portion of the aerosol-generating article may protrude longitudinally from the heating chamber.

[0006] The housing compartment is sealed to prevent ingress of dust or ingress of dust and water. The housing compartment may include a bottom plate. The bottom plate may seal an underside of the housing compartment. At least one of the heating element, the control electronics, and the battery are disposed within the housing compartment.

[0007] The heating element may be provided within or adjacent to the sealed housing compartment.

[0008] The heating element may be an electrical resistance heating element or an induction heating element such as an inductor, e.g., a coil. Control electronics may be provided 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 apparatus may be adapted 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 control electronics may be adapted such that the heating time to heat the heating element from ambient temperature to at least 80 degrees Celsius is less than 5 seconds, or less than 3 seconds.

[0009] The heating element and control electronics of the apparatus may be adapted to heat the aerosol-generating article to a temperature of 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 control electronics may be adapted such that the heating time to heat the aerosol-generating article from ambient temperature to at least 80 degrees Celsius is less than 5 seconds, or less than 3 seconds.

[0010] The heating element and control electronics of the apparatus may be adapted to heat the aerosol-generating article to a temperature of between 250 degrees Celsius and 400 degrees Celsius, or between 300 degrees Celsius and 350 degrees Celsius. The heating element and control electronics may be adapted such that the heating time to heat the aerosol-generating article from ambient temperature to at least 300 degrees Celsius is less than 60 seconds, or less than 30 seconds.

[0011] The heating element and control electronics may be adapted to heat in several successive heating cycles during consumption of one aerosol-generating article, where the temperature change of the heating element is at least 10 degrees Celsius, or at least 20 degrees Celsius.

[0012] Due to temperature changes of the gas in the housing compartment, the pressure in the housing compartment may increase. The ventilation means allows the gas to flow from the sealed housing compartment to the outside to prevent excessive pressure in the sealed housing compartment. The ventilation means may be adapted to allow the gas to flow from the outside into the sealed housing compartment to compensate for the low ambient pressure of the negative pressure in the low temperature phase during cooling or aerosol generation.

[0013] The ventilation means may be permeable to gas and impermeable to water, and therefore the aerosol generating device may be waterproof.

[0014] The ventilation means may have a water pressure resistance of at least 5 kPa, preferably at least 10 kPa, in particular about 12 kPa, which may make the device even more waterproof.

[0015] The ventilation means may have a ventilation capacity of 3000-7000 ml / cm2 min at 7 kPa, preferably 5000-5200 ml / cm2 min at 7 kPa, which allows rapid compensation for temperature changes within the aerosol generating device.

[0016] The venting means may be operable over a temperature range of -40 degrees Celsius to 150 degrees Celsius. In another embodiment, the venting means may be operable over a temperature range of -20 degrees Celsius to 90 degrees Celsius. The venting means may have the aforementioned ventilation capabilities over this entire temperature range. The venting means may have the aforementioned water pressure resistance over this entire temperature range.

[0017] The venting means may include a membrane. The membrane may be adapted to allow gas to flow through the membrane. The area of ​​the membrane may define the possible gas flow. The membrane may be adapted to prevent liquids, in particular water, from flowing through the membrane.

[0018] The venting means may include an expanded polytetrafluoroethylene membrane, which allows for the implementation of a preferably waterproof gas permeable membrane.

[0019] The venting means may include expanded polytetrafluoroethylene applied to a backing layer, which may be both gas and water permeable and may provide structural stability.

[0020] The venting means may include hydrophobic and oleophobic membranes, which allow the interior of the sealed housing compartment to be protected from polar liquids, such as water, and non-polar liquids, such as oil.

[0021] The venting means may include a membrane that is inert and UV resistant, thus improving the durability of the membrane when it comes into contact with potentially reactive materials from the environment.

[0022] The membrane may be connected to a carrier substrate having a central opening of at least 0.5 square millimeters, at least 1 square millimeter, or at least 2 square millimeters in size. 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.

[0023] The carrier substrate may improve the sealing properties of the membrane and its fluid-tight connection to the sealed housing compartment. The size of the opening dictates the potential gas flow at a given relative pressure to either side of the membrane.

[0024] The carrier substrate may be a double-sided adhesive layer that connects the membrane to the housing compartment, thus providing a dual function of sealing and connecting.

[0025] 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 structural stability, yet a sufficiently permeable membrane.

[0026] The membrane is disposed over and overlaps the opening in the housing compartment, thereby sealing the opening in the housing compartment while allowing air to vent through the membrane. The opening may be a perforation in the wall of the housing compartment.

[0027] The venting means 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 the bottom plate. The extension direction of the channel may be in a direction different from the opening direction of the housing opening. Thus, the venting means, in particular the membrane of the venting means, may be protected from contact with external objects. Fluid flow may be improved, since gas flow is less likely to be restricted by this geometry than liquid flow. The geometry of the channel and opening is particularly favorable for polar liquids, such as water, which may be prevented from reaching the membrane due to their surface tension. The extension direction of the channel may be perpendicular to the opening direction of the housing opening, in particular at an angle of at least 45 degrees, preferably at least 60 degrees.

[0028] The housing opening may have a cross-sectional area larger than the cross-sectional area of ​​the channel, so that a sufficiently large flow may be obtained through the housing opening despite the membrane being disposed therein.

[0029] The channels may have a cross-sectional area of ​​0.5 square millimeters to 2 square millimeters, which provides sufficient gas flow but makes it difficult for liquid to enter the channels.

[0030] The channel may be a recess extending into the housing compartment wall, so that gas may exit the channel at any point of its length extension. Alternatively, the channel may be a closed channel with walls on all sides along the flow direction.

[0031] The channel may connect the vent means to a recessed area in the housing compartment wall. The recessed area may have a larger opening towards the outside than the channel to facilitate gas escape.

[0032] The bottom plate may be secured by screws. By locating the venting means close to the screws, it is possible to provide the venting means in an area of ​​the aerosol generating device that is less likely to deform during normal handling, particularly due to tension in the screws. Thus, unintended relative movement of the aerosol generating device, the blocking channel, or a portion of the opening of the venting means is less likely to occur.

[0033] The screw head may be disposed within the recessed area, and thus the recess required to accommodate the screw head may provide a dual function for venting gas flow.

[0034] An electrical connector may be disposed within the recessed area such that the electrical connector opening may be used for ventilation.

[0035] The cover panel may be disposed outside the ventilation means, and a gap is provided between the cover panel and the ventilation means such that the ventilation means is disposed at a distance of 0.3 mm to 1 mm from the cover plate. Thus, it is possible to ventilate the gas flow between the cover panel and the ventilation means. Furthermore, the ventilation means may be protected from mechanical damage.

[0036] The bottom plate may include a transversely protruding sidewall. The cover panel may be secured to the interior of the protruding sidewall. The cover panel may be clipped to the bottom plate or secured by an adhesive.

[0037] The sealed housing compartment may contain electronic components and may protect the electronic components from being damaged by liquids.

[0038] The sealed housing section includes a button adapted to interact with control electronics within the sealed housing section, movement of the button changing the internal volume within the sealed housing section. Because the housing section is sealed, temperature changes will change the pressure within the housing section, which may change the position or stress of the button. The venting means ensures that the pressure within the sealed housing section does not change significantly, even during heating by the heating element, so that the button may operate with the same tactile properties at any time. The button may be overmolded with an elastic material to allow sealing of the housing section. The button may be attached with a double-sided adhesive tape to allow sealing of the housing section.

[0039] The ventilation means may comprise a membrane arranged on the outside of the housing compartment wall, in particular in the form of a bottom plate.

[0040] The ventilation means may comprise a membrane arranged on the inside of the housing compartment wall, in particular in the form of a bottom plate.

[0041] The membrane may be arranged in a recess in the housing compartment wall, which allows protection of the membrane, which may deform due to pressure.

[0042] According to a second aspect of the present invention there is provided an aerosol generation system comprising an aerosol generating device according to the first aspect of the present invention according to any of the embodiments described herein. The aerosol generation system also 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 which, when heated, releases a volatile compound capable of forming an aerosol.

[0043] The aerosol-forming substrate may comprise a tobacco plug. The tobacco plug may comprise one or more of powder, granules, pellets, shreds, spaghetti, strips, or sheets containing one or more of tobacco leaves, tobacco stem fragments, reconstituted tobacco, homogenized tobacco, extruded tobacco, and expanded tobacco. Optionally, the tobacco plug may contain additional tobacco or non-tobacco volatile flavor compounds that are released upon heating of the tobacco plug. Optionally, the tobacco plug may also include a capsule, for example, containing additional tobacco or non-tobacco volatile flavor compounds. Such capsules may melt during heating of the tobacco plug. Alternatively, or in addition, such capsules may be crushed before, during, or after heating of the tobacco plug.

[0044] When the tobacco plug includes 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. Alternatively, the homogenized tobacco material may have an aerosol former content of 5 to 30 percent by weight on a dry weight basis. The homogenized tobacco material sheet may be formed by agglomerating particulate tobacco obtained by grinding or otherwise comminuted one or both of tobacco lamina and tobacco stems, and alternatively, or additionally, the homogenized tobacco material sheet may include one or more of tobacco dust, tobacco fines and other particulate tobacco by-products formed, for example, during tobacco processing, handling and transportation. The homogenized tobacco material sheet may include one or more intrinsic binders (i.e., tobacco intrinsic binders), or one or more extrinsic binders (i.e., tobacco extrinsic binders), or a combination thereof, to assist in agglomerating the particulate tobacco. Alternatively, or in addition, the homogenized tobacco material sheet 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. Preferably, the homogenized tobacco material sheet is formed by a casting process of a type that generally involves casting a slurry including particulate tobacco and one or more binders onto a conveyor belt or other supporting surface, drying the cast slurry to form a homogenized tobacco material sheet, and removing the homogenized tobacco material sheet from the supporting surface.

[0045] The aerosol-generating article may have a total length of from about 30 millimeters to about 100 millimeters. The aerosol-generating article may have an outer diameter of from about 5 millimeters to about 13 millimeters.

[0046] The aerosol-generating article may include a mouthpiece located downstream of the tobacco plug. The mouthpiece may be located at the downstream end of the aerosol-generating article. The mouthpiece may be a cellulose acetate filter plug. The mouthpiece is preferably approximately 7 millimeters in length, but may have a length of approximately 5 millimeters to approximately 10 millimeters.

[0047] The tobacco plug may have a length of approximately 10 mm.The tobacco plug may have a length of approximately 12 mm.

[0048] The tobacco plug may have a diameter of from about 5 millimeters to about 12 millimeters.

[0049] In a preferred embodiment, the aerosol-generating article has an overall length of between about 40 millimeters and about 50 millimeters. Preferably, the aerosol-generating article has an overall length of about 45 millimeters. Preferably, the aerosol-generating article has an outer diameter of about 7.2 millimeters.

[0050] 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 the aerosol-generating article to generate an aerosol and allowing heated gas to flow from a sealed housing compartment of the aerosol generating device to the outside through a vent means. Thus, despite heating, the pressure inside the sealed housing compartment does not change significantly. The interior of the sealed housing compartment is at substantially ambient pressure despite heating.

[0051] Water can be prevented from entering the housing compartment from the outside through the ventilation means, thus protecting the control electronics inside the sealed housing compartment.

[0052] The vent gas can flow through the recess for the screw head, so that the volume between the wall of the screw head recess and the screw head can be used as a vent channel or outlet.

[0053] The vent gas may flow through the electrical connector opening, which may therefore be used as a vent outlet.

[0054] The ventilation gas can flow under the cover panel, thus protecting the ventilation means. The flow of heating gas can be distributed within the cover panel or to one or several outlets of the cover panel.

[0055] According to a fourth aspect of the present invention, there is provided the use of a venting membrane in an aerosol generating device to compensate for the thermal expansion of gas due to heat generated in a heating chamber receiving an aerosol generating article, thus preventing a pressure increase in the aerosol generating device due to the thermal expansion of the gas therein.

[0056] The apparatus according to the first aspect of the invention may be used according to the method of the third aspect of any of its embodiments of the invention. The method according to the third aspect of the invention may be carried out using an apparatus according to the first aspect of any of its embodiments of the invention, or a system according to the second aspect of any of its embodiments of the invention. The use of the breather membrane according to the fourth aspect of the invention may be carried out in an apparatus according to the first aspect of any of its embodiments of the invention, using method steps from the method according to the third aspect of any of its embodiments of the invention.

[0057] The embodiments will now be further described with reference to the figures. [Brief description of the drawings]

[0058] [Figure 1] FIG. 1 shows a perspective view of an aerosol generating device. [Diagram 2] FIG. 2 shows a cross section through the aerosol generating device of FIG. [Diagram 3]FIG. 3 shows a perspective view from below of the aerosol generating device of FIG. [Figure 4] FIG. 4 shows a partial perspective view from below of the aerosol generating device of FIG. 1 without the cover panel. [Diagram 5] FIG. 5 shows a partial cross-sectional view of the lower region of the aerosol generating device of FIG. [Figure 6] FIG. 6 shows a partial cross-sectional view of the lower region of the aerosol generating device of FIG. 1 with the inner holder removed. [Figure 7] FIG. 7 shows a partial cross-sectional view of the lower region of the aerosol generating device of FIG. [Figure 8] FIG. 8 shows a partial perspective view from below of an aerosol generating device according to a second embodiment of the invention without the cover panel. [Figure 9] FIG. 9 shows a perspective view of the bottom plate in the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0059] The present invention is defined in the claims. However, below 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 any other example, embodiment, or aspect described herein.

[0060] Example 1: An aerosol generating device comprising a heating chamber adapted to receive an aerosol generating article, a heating element, a sealed housing compartment, and ventilation means adapted to allow gas to flow from the sealed housing compartment to the outside of the aerosol generating device to compensate for thermal expansion of the gas inside the housing compartment due to the heating operation of the heating element. Example 2: An aerosol generating device according to example 1, wherein the ventilation means is permeable to gas and impermeable to water. Example 3: An aerosol generating device according to example 1 or 2, wherein the ventilation means has a water pressure resistance of at least 5 kilopascals, preferably at least 10 kilopascals, in particular about 12 kilopascals. Example 4: An aerosol generating apparatus according to any one of Examples 1 to 3, wherein the ventilation means has a ventilation capacity of 3000 to 7000 milliliters per square centimeter per minute at 7 kilopascals, preferably 5000 to 5200 milliliters per square centimeter per minute at 7 kilopascals. Example 5: 5. An aerosol generating apparatus according to any one of Examples 1 to 4, wherein the ventilation means operates in a temperature range of -40 degrees Celsius to 150 degrees Celsius. Example 6: 6. An aerosol generating device according to any one of Examples 1 to 5, wherein the ventilation means comprises a membrane. Example 7: 7. An aerosol generating device according to any one of Examples 1 to 6, wherein the ventilation means comprises a membrane made of expanded polytetrafluoroethylene. Example 8: An aerosol generating device according to any one of Examples 1 to 7, wherein the venting means comprises expanded polytetrafluoroethylene applied to the backing layer. Example 9: An aerosol generating device according to any one of Examples 1 to 8, wherein the ventilation means comprises a hydrophobic membrane and an oleophobic membrane. Example 10: An aerosol generating device according to any one of Examples 1 to 9, wherein the ventilation means comprises an inert and UV-resistant membrane. Example 11: An aerosol generating device according to any one of Examples 1 to 10, wherein the venting means comprises a membrane, the membrane being 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. Example 12: An aerosol generating device according to Example 11, wherein the carrier substrate is a double-sided adhesive layer that connects the membrane to the housing section. Example 13: An aerosol generating device according to any one of Examples 6 to 12, wherein the membrane has a thickness of 0.05 to 0.5 milliliters, preferably 0.1 to 0.2 millimeters, in particular about 0.15 millimeters. Example 14: An aerosol generating device according to any one of Examples 6 to 13, wherein the membrane is disposed overlapping the opening of the housing section. Example 15: An aerosol generating device according to any one of Examples 1 to 14, wherein the ventilation means includes a housing opening within the housing compartment and a channel extending into the housing compartment wall, the extension direction of the channel being in a direction different from the opening direction of the housing opening. Example 16: An aerosol generating device according to Example 15, wherein the housing opening has a cross-sectional area larger than the cross-sectional area of ​​the channel. Example 17: 17. An aerosol generating device according to embodiment 15 or 16, wherein the channel has a cross-sectional area of ​​0.5 square millimeters to 2 square millimeters. Example 18: An aerosol generating device according to any one of Examples 15 to 17, wherein the channel is a recess extending into the housing compartment wall. Example 19: An aerosol generating device according to any one of Examples 15 to 18, wherein a channel connects the vent means to a recessed area of ​​the housing compartment wall. Example 20: 20. The aerosol generating device according to example 19, wherein the screw head is disposed within the recessed area. Example 21: 21. The aerosol generating device according to embodiment 19 or 20, wherein the electrical connector is disposed within the recessed area. Example 22: An aerosol generating device according to any one of Examples 1 to 21, wherein the cover panel is disposed outside the ventilation means and a gap is provided between the cover panel and the ventilation means such that the ventilation means is disposed at a distance of 0.3 millimeters to 1 millimeter from the cover panel. Example 23: An aerosol generating device according to any one of Examples 1 to 22, wherein the sealed housing compartment contains an electronic component. Example 24: An aerosol generating device according to any one of Examples 1 to 23, wherein the sealed housing compartment includes a button adapted to interact with control electronics within the sealed compartment, and movement of the button changes the internal volume of the sealed housing compartment. Example 25: An aerosol generating device according to any one of Examples 1 to 24, wherein the ventilation means comprises a membrane disposed on the outside of the housing compartment wall. Example 26: An aerosol generating device according to any one of Examples 1 to 25, wherein the ventilation means comprises a membrane disposed on the inside of the housing compartment wall. Example 27: 27. An aerosol generating device according to embodiment 25 or 26, wherein the membrane is disposed within a recess in the housing compartment wall. Example 28: 1. A method for operating an aerosol generating system, comprising: - inserting an aerosol-generating article into a heated chamber of an aerosol-generating device; - heating the aerosol-generating article to generate an aerosol; - allowing the heated gas to flow from the sealed housing compartment of the aerosol generating device to the outside through a ventilation means. Example 29: The method according to example 28, further comprising the step of preventing water from entering the housing compartment from the outside through the ventilation means. Example 30: The method according to embodiment 28 or 29, wherein the ventilation gas flows through a recess for the screw head. Example 31: The method according to any one of embodiments 28-30, wherein the vent gas flows through the electrical connector opening. Example 32: The method according to any one of embodiments 28 to 31, wherein the ventilation gas flows under the cover panel. Example 33: The use of a venting membrane in an aerosol generating device to compensate for the thermal expansion of gas due to heat generated in a heated chamber receiving the aerosol generating article. Example 34: An aerosol-generating system comprising an aerosol-generating device according to any one of the preceding Examples 1-26 and an aerosol-generating article, the aerosol-generating article comprising an aerosol-forming substrate.

[0061] An aerosol generating device 1 according to a first embodiment of the invention is shown in an upright orientation in Figure 1. The aerosol generating device 1 comprises a housing 2 and a cover element 3 slidably arranged in a transverse direction 100 on the housing 2. The housing 2 extends mainly in a longitudinal height direction 200 and has its relatively minimal extension in a width direction 300. The cover element 3 is shown in Figures 1 and 2 in a closed position covering an opening of a heating chamber 4.

[0062] When the cover element 3 is in the open position, the heating chamber 4 is adapted to receive a rod-shaped aerosol-generating article and heat the aerosol-generating article by means of a heating element 5. The heating element 5 is an induction coil module adapted to heat a susceptor, which may be part of the rod-shaped aerosol-generating article. The heating element 5, control electronics 6 and battery 7 are disposed within a housing compartment 8 of the housing 2.

[0063] The housing section 8 is sealed to prevent water or dust from entering the housing section 8. The housing section 8 may include a button 9 that is overmolded and sealed.

[0064] When the aerosol-generating article is heated, an aerosol is generated, which can be consumed in the same manner as a cigarette, with the rod-shaped mouth end protruding from the heating chamber. For a beneficial consumer experience, sufficient and rapid aerosol delivery is desirable. This requires sufficient and rapid heating of the aerosol-generating article. The heating of the aerosol-generating article is therefore performed at a relatively high power. This means that not only the aerosol-generating article, but also the heating element 5 and the control electronics 6 and the battery 7 generate heat inside the housing compartment 8 and heat the gas, i.e. the air.

[0065] During aerosol generation, gas inside housing section 8 heats up and expands rapidly, causing an increase in pressure inside the sealed housing section 8, which in turn acts against the interior of button 9, changing the appearance of button 9 or the activation experience of the user.

[0066] To avoid such a pressure build-up inside the housing section 8, venting means 10 are provided in the lower region of the aerosol generating device 1. The venting means 10 are provided next to the electrical connector opening 11.

[0067] The venting means 10 is at least partially disposed on a bottom plate 12 of the housing section 8. The bottom plate 12 is connected by screws 13 to close the housing section 8. A cover panel 14 is connected to the bottom plate and covers the screws 13. A gap 15 is provided between the bottom plate 12 and the cover panel 14. The gap 15 allows gas to flow between the bottom plate 12 and the cover panel 14. The bottom plate 12 includes a protruding side wall 16 as seen in FIG. 4. The cover panel 14 is connected to the protruding side wall 16 by an adhesive.

[0068] 3, an electrical connector, such as a USB-C connector, is provided at electrical connector opening 11. Channel 17 in venting means 10 opens to electrical connector opening 11. Channel 17 allows gas to flow through venting means 10.

[0069] 4, the cover panel 14 has been removed to reveal the channel 17 in full view. The channel 17 leads to an opening 18 in the bottom plate 12.

[0070] The channels 17 extend in a width direction 300 and the openings 18 extend in a transverse direction 100. To allow for a constant wall thickness of the bottom plate 12, recessed areas 19 are provided in the bottom plate 12 beside the openings 18 and channels 17 of the vent means 10. This facilitates manufacture of the bottom plate by injection molding and allows for beneficial channel 17 and opening 18 geometries.

[0071] As shown in FIG. 5, an optional spacer 20 is disposed inside the bottom plate 12. The spacer 20 may be elastic. The bottom plate 12 includes a protrusion 21 that engages with a recess 22 of the spacer 20. The spacer 20 is disposed between and in contact with both the holder 23 and the bottom plate 12. In particular, the holder 23 may be part of or connected to the battery holder 24. The spacer 20 has a central spacer opening 25 and the holder 23 has a central holder opening 26. The spacer opening 25 and the holder opening 26 extend in a transverse direction and are substantially aligned. A membrane 27 is disposed 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. Carrier substrate 28 has a central opening 29 that is substantially aligned with openings 25 and 26 in spacer 20 and holder 23. Membrane 27 allows the flow of gas but prevents the flow of liquid.

[0072] In Fig. 8 a second embodiment of an aerosol generating device 1 according to the invention is shown. For the purposes of illustration, the bottom plate 12, which corresponds to that of the first embodiment, has been removed. The venting means 30 is arranged between the recesses 31 for the heads 32 of the screws 13 and the electrical connector openings 11. The venting means 30 comprises a first channel 33 leading to the electrical connector openings 11. The venting means 30 comprises a second channel 34 leading to the screw recesses 31. Thus, during venting, air from the interior of the housing section 8 can flow through the channels 33, 34 to the electrical connector openings 11 and the screw recesses 31 and then to the outside. The venting means 30 comprises a membrane 35 that is permeable to gases but not to liquids. The membrane 35 is arranged on a carrier substrate 36, which may be in the form of a double-sided adhesive tape that connects the membrane 35 to the bottom plate 12. In the second embodiment, the membrane 35 is disposed on the outside of the bottom plate 12 , and in the first embodiment, the membrane is disposed on the inside of the button plate 12 .

[0073] The bottom plate 12 of the second embodiment is shown in isolation in Figure 9. A recess 37 for receiving a membrane 35 and a carrier substrate 36 are provided. The membrane 35 covers an opening 38 provided centrally in the recess 37.

[0074] In one embodiment of the method according to the invention, the aerosol-generating rod is inserted into the heating chamber 4 and heated therein. Inside the housing section 8 of the aerosol-generating device 1, the gas is heated and thus the pressure increases through the thermal expansion of the gas. Due to the provision of the ventilation means 10 or 30, the gas flows through the membrane 35 and the channel 17 in the first embodiment and through the membrane 35 and the channels 33 and 34 in the second embodiment and then to the outside. Thus, the gas can enter and leave the housing section 8 to compensate for the thermally generated pressure difference. 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 membranes 27, 25, the incorporation of water or dust in the device can be prevented.

[0075] The channels 17, 33, 34 may be in the form of recesses in the bottom plate 12 which form tubular channels when closed by the cover panel 14. Preferably, the cover panel is disposed at a distance from the vent membrane such that a gap is provided between the cover panel 14 and the vent means 10, 30.

[0076] The ventilation means 10 may be located intermediately 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 bottom plate 12 and the cover panel 14 has a height that anticipates potential deformation of the membrane 35 due to pressure. The ventilation air in the screw recess 31 may leak out along the flow path between the cover panel 14 and the side wall 16 of the bottom plate 12 to the outside.

[0077] For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers expressing amounts, quantities, percentages, and the like should be understood in all cases as being modified by the term "about." Also, all ranges include the maximum and minimum points disclosed, and include any intermediate ranges therein, which may or may not be specifically recited herein. Thus, in this context, the number A is understood as A ± 10% of A. Within this context, the number A may be considered to include numerical values ​​that are within the general standard error for the measurement of the property that the number A modifies. The number A may, in some instances used in the appended claims, deviate by the percentages recited above, provided that the amount by which A deviates does not materially affect the basic and novel properties of the claimed invention. Also, all ranges include the maximum and minimum points disclosed, and include any intermediate ranges therein, which may or may not be specifically recited herein.

Claims

1. An aerosol generating device, comprising: a heating chamber adapted to receive an aerosol-generating article; a sealed housing section; a heating element provided in the sealed housing section; and a ventilation means adapted to allow gas to flow from the sealed housing compartment to the outside of the aerosol generating device to compensate for thermal expansion of gas inside the housing compartment due to the heating operation of the heating element.

2. 2. The aerosol generating device according to claim 1, wherein the venting means has a water pressure resistance of at least 5 kPa, preferably at least 10 kPa, in particular about 12 kPa.

3. 3. The aerosol generating device according to claim 1 or 2, wherein the ventilation means has a ventilation capacity of 3000 to 7000 milliliters per square centimeter per minute at 7 kilopascals, preferably 5000 to 5200 milliliters per square centimeter per minute at 7 kilopascals.

4. 4. An aerosol generating device according to any one of claims 1 to 3, wherein the venting means comprises expanded polytetrafluoroethylene applied to a backing layer.

5. 5. The aerosol generating device of claim 1, wherein the venting means comprises a membrane, the membrane being connected to a carrier substrate having a central opening of at least 0.5 square millimeters, at least 1 square millimeter, or at least 2 square millimeters in size.

6. 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 as described in any one of claims 1 to 6, wherein the ventilation means includes an opening in the housing compartment and a channel extending into the housing compartment wall, the direction of extension of the channel being different from the opening direction of the housing opening.

8. 8. The aerosol generating device of claim 7, wherein the channel is a recess extending into a housing compartment wall.

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

10. The aerosol generating device of claim 9 , wherein a screw head is disposed within the recessed area.

11. 11. The aerosol generating device of claim 9 or 10, wherein an electrical connector is disposed within the recessed area.

12. 12. An aerosol generating device according to any one of claims 1 to 11, wherein a cover panel is disposed outside the ventilation means, providing a gap between the cover panel and the ventilation means.

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

14. An aerosol generating device as described in any one of claims 1 to 13, wherein the sealed housing compartment includes a button adapted to interact with control electronics within the sealed housing compartment, and movement of the button changes the internal volume of the sealed housing compartment.

15. 1. A method for operating an aerosol generating system, comprising: - inserting an aerosol-generating article into a heated chamber of an aerosol-generating device; - heating the aerosol-generating article by means of a heating element to generate an aerosol, the heating element being provided in a sealed housing compartment of the aerosol generating device; - allowing heated gas to flow from said sealed housing compartment to the outside through a ventilation means.

16. The use of a vent membrane in an aerosol generating device comprising a heating element within a sealed housing compartment to compensate for thermal expansion of gas due to heat generated within a heated chamber receiving an aerosol generating article.

17. 1. An aerosol generation system comprising: An aerosol generating device according to any one of claims 1 to 14, and an aerosol-generating article comprising an aerosol-generating substrate.

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