Aerosol-generating device with cleaning means

Abstract

The present invention relates to an aerosol-generating device (100) comprising: a longitudinal heating cavity (10) delimited by a lateral wall (12), the heating cavity (10) being provided with an opening (14) at one upper end (10a) and being adapted to receive at least a portion of an aerosol-generating article inserted through said opening (14); and a heating system (20) for heating the aerosol-generating article (1) received in the heating cavity (10). According to the invention, the device (100) comprises a one-piece cleaning tool (30) configured to move longitudinally within the heating chamber (10) upon actuation of the actuator (60), and comprising at least one cleaning member (40) configured to move longitudinally within the heating chamber (10) upon actuation of the actuator (60). The at least one cleaning member is configured to flexibly wipe a lateral wall (12) of the heating cavity (10) when moving along the heating cavity (10).

Description

Technical Field

[0001] The present invention relates to an aerosol generating device. Background Art

[0002] Nowadays, aerosol-generating devices are increasingly used as alternatives to regular cigarettes. A special type of aerosol-generating device is a heat-not-burn device (HnB), which heats an aerosol-generating substrate rather than burning or igniting the aerosol-generating substrate to produce an aerosol that a user can inhale.

[0003] A heat-not-burn aerosol-generating device typically comprises a heating cavity adapted to receive at least a portion of a consumable aerosol-generating article inserted into the heating cavity, and a heating system for heating the article contained in the cavity.

[0004] The aerosol-generating article comprises a tobacco substrate containing an aerosol-forming substance (such as glycerol and / or propylene glycol) which vaporizes during heating and produces a vapor that extracts nicotine and flavor components from the tobacco substrate. The aerosol-forming substance is heated to a temperature between 200°C and 400°C, which is lower than the normal burning temperature of a conventional cigarette.

[0005] The volatile compounds and aerosol released when the tobacco substrate is heated are deposited on the inner surfaces of the aerosol-generating device. In addition, fragments or particles of the aerosol-generating article itself (such as fragments or particles from the wrapper of these aerosol-generating articles, or fragments or particles from the substrate) may be dislodged when the article is handled or used.

[0006] Foreign material, such as dirt, may penetrate further into the heating chamber between uses.

[0007] All these residues are deposited in particular on the lateral surfaces of the heating chamber. These residues can further accumulate and / or be partially removed by friction of the inserted aerosol-generating article.

[0008] These residues prevent optimal use of the aerosol generating device. When accumulated on the walls of the heating chamber, these residues may reduce or block the airflow required by the device. These residues may also affect the optimal flavor perception of the aerosol. In fact, the contaminating fragments or particles may give the user an unpleasant or bitter flavor. Moreover, the heater may be damaged, depending on how or where the residue is deposited.

[0009] Today, users often clean their devices themselves using specialized cleaning tools, such as brushes. Besides the potential unpleasant experience and burden on the user, this manual cleaning can have a negative impact on the sustainability of the device and the user experience. The heater can be damaged by too much or too little cleaning. Furthermore, insufficient cleaning can result in a reduced user experience during use and can create unpleasant odors.

[0010] Therefore, there is a need for improved management of residues within aerosol-generating devices to improve the user experience during inhalation and to more generally improve the sustainability of the devices. Summary of the invention

[0011] This is achieved by an aerosol generating device comprising:

[0012] - a heating cavity extending in a longitudinal direction along a longitudinal axis and delimited by lateral walls in a lateral direction orthogonal to said longitudinal direction, the heating cavity being provided with an opening at one upper end and being adapted to receive at least a portion of an aerosol-generating article inserted through said opening, and

[0013] - a heating system for heating the aerosol-generating article received in the heating chamber,

[0014] The aerosol generating device is characterized in that the aerosol generating device further includes an integrated cleaning tool, which is configured to move longitudinally in the heating cavity when the actuator is actuated, and the integrated cleaning tool includes at least one cleaning member, which is configured to flexibly wipe the lateral wall of the heating cavity when moving along the heating cavity.

[0015] According to the invention, the aerosol generating device is provided with a cleaning system comprising a dedicated cleaning tool and an actuator which actuates the cleaning tool when the cleaning process is triggered.

[0016] The cleaning tool can, for example, be automatically operated by a control unit integrated in the device, which is configured to control one or several parameters, such as the time period since the last cleaning process and / or the number of suction processes and / or the temperature of the heating system and / or the charge state of the battery and / or the resistance or impedance at the lateral walls of the cavity, and is configured to trigger the actuator based on the (one or several) parameters.

[0017] Additionally or alternatively, the cleaning tool may be operated based on an actuation command by a user, such as an actuation button on the device.

[0018] In particular, the actuator may be actuated according to the actual cleaning need, in particular according to one or several parameters representing the degree of contamination of the heating chamber, these parameters being typically measured by at least one sensor.

[0019] According to the invention, the cleaning tool comprises at least one cleaning member at its periphery, wherein the cleaning member is deformed to bear against the lateral walls of the heating chamber in order to wipe or brush said lateral walls.

[0020] At least one lateral dimension of the cleaning tool (in an unmounted state) may, for example, be larger than a lateral dimension of the cavity.

[0021] When the cleaning tool is moved in the longitudinal direction, the cleaning member(s) resiliently biased against the lateral wall removes the residue deposited on the lateral wall.After the residue is removed from the wall, it can be easily discharged by, for example, simply rotating the device.

[0022] The automatic cleaning provided by the cleaning tool improves the user experience by eliminating the burden of manual cleaning. This also ensures consistency in the cleaning operation: the heating chamber is always kept in good condition, thereby improving the user's experience during smoking and increasing the sustainability of the device.

[0023] In the following, a lateral direction is a direction orthogonal to the longitudinal axis of the heating chamber and intersecting said axis. In the absence of indications to the contrary, a transverse plane is a plane orthogonal to the longitudinal direction.

[0024] The cleaning tools may have a variety of shapes and arrangements, as will be described in more detail below.

[0025] The cleaning tool may include a single cleaning member or a plurality of cleaning members.

[0026] According to an embodiment, the length of each cleaning member measured in the lateral direction may be between 0.1 mm and 1 mm.

[0027] The thickness of each cleaning member measured in the longitudinal direction may preferably be between 0.01 mm and 0.5 mm, more preferably between 0.05 mm and 0.2 mm.

[0028] The cleaning tool may be movable along the cavity with only one degree of freedom (translation in the longitudinal direction without rotation), or may be movable with two degrees of freedom (ie, simultaneous translation in the longitudinal direction and rotation about the longitudinal axis of the cavity).

[0029] The arrangement of the cleaning element(s) can be chosen in particular depending on the thickness of each cleaning element, the presence or absence of a rotational movement of the tool, the translation speed and / or the rotation speed of the tool, with the aim of brushing the maximum area of ​​the lateral wall of the cavity at least once during one longitudinal movement of the tool.

[0030] Advantageously, the position of the cleaning member(s) may also be adapted to the shape of the heating chamber and / or the position of specific elements of the device, depending on the cleaning requirements of these parts or, conversely, on their fragility (some parts break easily and direct contact of these parts with cleaning tools should be avoided).

[0031] Advantageously, the integrated cleaning tool may include multiple cleaning members that are deformable independently of one another.

[0032] Each cleaning member is flexible and can match the internal shape of the heating cavity, which may or may not be circular. Providing several cleaning members that are deformable independently of each other and can bend accurately according to the portion of the heating cavity being wiped can better match the shape of the cavity, thereby achieving efficient cleaning.

[0033] A cleaning member is provided at the periphery of the cleaning tool so as to flexibly wipe the lateral walls of the heating cavity while moving along said heating cavity.

[0034] For example, an integrated cleaning tool may include a plurality of spaced-apart cleaning members.

[0035] The cleaning members may be distributed over the whole or part of the tool circumference, preferably in a regular arrangement, in particular in the form of a single cleaning layer, over the whole or part of the tool circumference.

[0036] According to an embodiment, each cleaning member may have an elongated shape along a lateral direction (hereinafter referred to as the main direction / axis of that particular cleaning member).

[0037] The cross-section of the cleaning member orthogonal to its main axis may be circular, rectangular or any other shape.

[0038] According to an embodiment, the maximum dimension of each cleaning member (measured in a plane orthogonal to the main axis of the cleaning member) may be between 0.01 mm and 0.5 mm, preferably between 0.05 mm and 0.2 mm.

[0039] According to an embodiment, each cleaning member may be inscribed in an angular sector around the longitudinal axis of less than 1°, or even less than 0.5°.

[0040] A plurality of cleaning members may be spaced larger. According to an example, only four elongated cleaning members may be arranged in a cross around the perimeter of the tool, wherein two adjacent cleaning members form an angle of 90°.

[0041] According to another preferred embodiment, the cleaning tool may comprise a plurality of juxtaposed cleaning members to form a cleaning comb. Each cleaning member then forms a tooth of the comb, wherein the plurality of cleaning members are arranged closely adjacent to each other.

[0042] Such a cleaning comb may extend along the entire periphery of the tool (ie, extend at 360° around the longitudinal axis). Alternatively, the cleaning comb may extend only over a portion or an angular portion at the periphery.

[0043] According to another embodiment, the at least one cleaning member may be a flexible scraper having a flat and wide blade shape.

[0044] Such a flexible scraper may extend continuously along the entire periphery of the tool (ie, extend 360° around the longitudinal axis). Alternatively, the cleaning comb may extend only over a portion or an angular portion at the periphery.

[0045] The or each cleaning member may be made from plastic, such as silicone or polyetheretherketone (PEEK), or metal, such as stainless steel, or any other suitable material.

[0046] The or each cleaning member may also be partially coated (particularly at its end) or fully coated to enhance the wiping action. The coating may comprise, for example, polytetrafluoroethylene (PTFE), silicon or any other suitable material. The coating may be applied, for example, by dipping, or dipping and centrifuging, or any other coating technique.

[0047] According to an embodiment, and in order to facilitate the release of debris brushed off by (one or more) cleaning members, the cleaning tool can include at least one cleaning zone having at least one cleaning member and at least one free zone at its periphery and in particular when viewed in lateral projection, wherein the or each free zone extends over an angular sector of at least 35° around the longitudinal axis, preferably over an angular sector of at least 70° around said longitudinal axis.

[0048] More specifically, the cleaning tool may include alternating cleaning zones and free zones at its periphery.

[0049] In the present application, a cleaning zone is understood to be formed by one cleaning member or by a plurality of closely juxtaposed cleaning members. In particular:

[0050] The cleaning zone may be formed by a single cleaning member which typically extends continuously over an angular section of at least 35°, preferably at least 70° around the longitudinal axis.

[0051] As an alternative, the cleaning zone may comprise a cleaning comb formed by a plurality of juxtaposed cleaning members extending laterally.

[0052] The cleaning member or members may be defined in a plane (typically a transverse plane or a plane inclined relative to the transverse plane) thereby forming a so-called cleaning layer.

[0053] According to a particular embodiment, the cleaning tool may comprise several cleaning layers stacked in the longitudinal direction, each layer typically comprising one or several cleaning members and / or zones.

[0054] According to an embodiment, the cleaning tool may comprise at least one air channel arranged on both its lateral side and its upper side.

[0055] Air channel is configured to allow air to flow from the lateral side of the cleaning tool to its upper side. Therefore, the cleaning tool allows air to flow to the end of the tobacco rod, which is necessary for improving the suction efficiency.

[0056] The cleaning tool typically comprises a central tool body, and each cleaning member is formed at a periphery of the tool body.

[0057] According to an embodiment, each cleaning member may be integrally formed with the body.

[0058] According to another embodiment, the cleaning tool may comprise a body, and at least one cleaning member may be detachably fixed to the body.The cleaning member(s) may be easily replaced if necessary (eg due to use).

[0059] In particular, the cleaning tool may comprise fixing means for fixing the cleaning member(s) to the tool body.

[0060] According to a particular embodiment, the body may comprise an upper body portion and a lower body portion acting as clamping jaws.The cleaning tool may also be provided with fixing means, typically threaded fixing means, for fixing the upper body portion and the lower body portion to each other.

[0061] According to an embodiment, each cleaning member may form part of a separate cleaning module which is independently detachable from the tool body.

[0062] As an advantageous alternative, in order to facilitate assembly and disassembly of several cleaning members to and from the tool body, the cleaning tool may comprise at least one one-piece cleaning module having several (preferably all) cleaning members and detachably secured to the tool body.

[0063] In particular, several cleaning members forming a cleaning zone may be connected together, typically at a central base, to form a cleaning module.

[0064] Furthermore, cleaning components of one cleaning zone may be connected to components of other cleaning zones to form a cleaning module.

[0065] In the above-mentioned comb-like configuration, the cleaning module may be formed by etching a metal sheet (eg, stainless steel or titanium) to form the cleaning members at its periphery.

[0066] According to an alternative embodiment, the cleaning module may be formed from a folded wire, wherein the folds of the wire form the cleaning members.

[0067] According to an embodiment, the cleaning tool may be provided with a collection cup located below the cleaning zone(s) to collect debris brushed off by the cleaning member(s) as the tool moves in the cavity. The cleaning member(s) and collection cup(s) may be integrally formed (molded or injection molded), or may be fastened and removed to each other and / or to the tool body, for example by press fit / screw / magnet engagement.

[0068] The heating cavity extends in a longitudinal direction along a longitudinal axis and is bounded by lateral walls in a lateral direction orthogonal to said axis. The cavity has a generally tubular shape. The cavity is fixed relative to the outer body of the device.

[0069] More generally, the device comprises an outer body in which the heating cavity, the heating system and the power supply are received and the heating cavity, the heating system and the power supply are all fixed relative to each other and to the outer body.

[0070] The heating cavity is provided with an insertion opening at its insertion end. The opening allows the aerosol-generating article to be introduced into the interior of the cavity.

[0071] In the present disclosure, and in the absence of specific indications to the contrary, the terms "top", "bottom", "upper part" and "lower part" are considered relative to the longitudinal axis of the heating cavity, with the top part and the upper part being oriented toward the insertion end of the cavity and the bottom part and the lower part being oriented toward the end opposite to the insertion end.

[0072] According to an embodiment, the cleaning tool may be configured to be stored in a retracted position at the bottom end of the heating cavity when the actuator is at rest. In the retracted position, the cleaning tool then forms the bottom portion of the heating cavity, thereby allowing the aerosol-generating article to be in the position required for normal inhalation use inside the cavity.

[0073] The heating system may include a heater surrounding the heating cavity and configured to heat the heating cavity.

[0074] The heater may typically comprise a heater body in the form of a longitudinal metallic sleeve and a heating element such as a thick film or thin film heater comprising layers of electrically insulating material and electrically conductive material located outside or inside the heater body.

[0075] The heater body can also be made of ceramic.

[0076] Alternatively, the heating system may comprise an induction coil typically surrounding the heating cavity and configured to heat by induction a ferromagnetic material forming part or all of the heating cavity or contained in the aerosol-generating article.

[0077] According to an embodiment, the heater body may have a cup shape. That is, the heater body may have a lateral tubular wall and a bottom wall.

[0078] According to an embodiment, the heater body may be integral with a holder, which is typically made of high temperature resistant plastic and is configured to hold the heater body at the lower end. The holder may have a base orthogonal to the longitudinal direction of the heating cavity and a holding device (such as a longitudinal tongue) protruding upward from the base, which is configured to hold the heater body, for example by clamping.

[0079] In particular, the holding means may be configured to hold the heater body at a distance from the base.

[0080] According to an embodiment, the actuator configured to actuate the cleaning tool to move longitudinally inside the heating chamber is a mechanical linear actuator, also known as a screw-nut type lead screw actuator, which includes a screw or shaft extending in the longitudinal direction and a nut threadedly engaged with the screw.

[0081] The actuator may further include a motor for driving the screw.

[0082] The rotary motor can have a direct drive or an indirect drive, and in the case of an indirect drive its axis is aligned with the screw axis or offset relative to the screw axis.

[0083] According to an advantageous embodiment, the actuator may include a reduction gear between the motor and the screw. Such a reduction gear may transmit the rotational movement of the motor shaft to the screw while reducing the speed and increasing the torque delivered to the screw. The reduction gear may, for example, include a first cogwheel integral with the motor shaft and a second cogwheel integral with the screw or engaged with the screw.

[0084] According to an embodiment, the nut is fixed in the longitudinal direction of the heating chamber, the screw can translate in the longitudinal direction when the nut rotates, and the cleaning tool is integral with the screw. In this type of actuator (also known as a through-shaft linear actuator), the cleaning tool rotates with the screw while moving along the heating chamber. In order to allow this movement, the cleaning tool typically has a circular cross-section that conforms to the circular cross-section of the heating chamber.

[0085] In an embodiment comprising a reduction gear as described above, the cogwheel of the reduction gear may be provided with a threaded hole for engagement with a screw rod, and a nut may thereby be formed.

[0086] According to another embodiment, the tool body can be supported at the end of the screw in a freely rotatable manner, for example by at least one ball bearing. According to one example, the hub of the ball bearing can be formed by a support element integral with the top end of the screw, and the shaft of the ball bearing can be integral with the tool body, or vice versa.

[0087] According to another embodiment, the screw is fixed in the longitudinal direction of the heating chamber, the nut can translate along the longitudinal direction when the screw rotates, and the nut is formed by or integrated with the cleaning tool. The advantage of this embodiment is that the space below the heating chamber will not become cluttered.

[0088] For cavities with non-circular cross-sections, the cleaning tool can be fixed with one degree of freedom so as to move in the longitudinal direction without rotation.

[0089] In embodiments comprising a reduction gear as described above, the cogwheel of the reduction gear may be fixedly attached to the screw.

[0090] According to an embodiment, the screw may be laterally offset relative to a central axis of the heating chamber.

[0091] In embodiments where the heater body is cup-shaped, the screw may pass through an opening formed in a bottom wall of the heater body.

[0092] Advantageously, the edge of the bottom wall around the screw opening can then be turned up to prevent dirt from falling into the device. An additional seal, such as a silicone seal, around the opening can also be arranged to prevent dirt from falling out.

[0093] According to an embodiment, the device may comprise a control unit for controlling one or several parameters, in particular for controlling one or several parameters representing the degree of contamination of the heating chamber, and for actuating the actuator based on said parameter(s).

[0094] In particular, the device may comprise at least one sensor configured to measure at least one parameter representative of a degree of contamination of the heating chamber and to send a corresponding signal to the control unit.

[0095] The invention also relates to a method for cleaning an aerosol generating device as defined above, the method comprising: actuating an actuator to achieve a longitudinal movement of the cleaning tool inside the heating chamber.

[0096] According to an embodiment, the cleaning method further comprises measuring at least one parameter representing a degree of contamination of the heating chamber in a closed-loop manner and actuating the actuator based on said parameter.

[0097] Any sensor configured to assess the degree of fouling in the cavity may be implemented in the method.The measured parameter may be directly related to the degree of fouling or may allow prediction of said degree of fouling.

[0098] In particular, at least one parameter may be the resistance or impedance at a lateral wall typically formed by the heater body and / or the time period since the last cleaning process and / or the number of purge processes since the last cleaning process and / or the temperature of the heating system and / or the charge state of the battery.

[0099] According to an advantageous embodiment, the measuring step may comprise measuring resistance or impedance.

[0100] According to an embodiment, the cleaning step may include moving the cleaning tool back and forth along the heating chamber several times at different speeds and / or at different temperatures.

[0101] It should be understood that the different embodiments mentioned above can be implemented individually or in any technically compatible combination. Specifically, without departing from the scope of the present invention, the technical features mentioned above and the technical features to be described below can be used not only in the combinations shown, but also in other combinations or alone. BRIEF DESCRIPTION OF THE DRAWINGS

[0102] Figure 1A is a schematic cross-sectional view of an aerosol generating device according to an embodiment of the present invention; wherein the cleaning tool is in its retracted position, in which the cleaning tool forms the bottom of the heating cavity;

[0103] Figure 1B yes Figure 1A A cross-sectional view of the aerosol generating device in , wherein the cleaning tool is in the most deployed position;

[0104] Figure 2 yes Figure 1B View of detail II in the;

[0105] Figure 3 yes Figure 1A , Figure 1B and Figure 2 A partial stereoscopic view of the actuator in FIG.

[0106] Figure 4 A single-axis actuator is shown, the motor of which is aligned with the screw;

[0107] Figure 5 A cleaning tool having a two-part tool body and a removable cleaning member is shown;

[0108] Figure 6 yes Figure 5 A three-dimensional view of the upper body portion of the cleaning tool;

[0109] Figure 7 is a perspective view of a cleaning tool including a cleaning comb formed of juxtaposed cleaning members;

[0110] Figure 8 is a partial perspective view of a cleaning tool having a coated cleaning member;

[0111] Fig. 9 is a perspective view of a cleaning tool including a cleaning module formed of folded wire;

[0112] Fig.10 is a perspective view of a cleaning tool including a scraper-shaped cleaning member;

[0113] Fig.11 is a perspective view of a cleaning tool having alternating cleaning and free areas along its periphery;

[0114] Fig.12 is a cross-sectional view of a cleaning tool having two superimposed cleaning layers;

[0115] Fig.13 is a cross-sectional view of a cleaning tool including a collection cup for collecting debris brushed off by a cleaning member;

[0116] Fig.14 is a cross-sectional view of a cleaning tool wherein the upper end of the screw is free to rotate.

[0117] Fig.15 is a diagram showing an implementation mode (including closed-loop control) of the cleaning method according to the present invention. DETAILED DESCRIPTION

[0118] The present invention will be described with respect to specific embodiments and with reference to the accompanying drawings, but the invention is not limited thereto. In the drawings, which are merely schematic, the dimensions of some elements may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and relative dimensions do not correspond to actual reductions in the practice of the present invention.

[0119] Figure 1A An aerosol generating device 100 according to an embodiment of the invention is shown.

[0120] The device 100 comprises an outer body 2 of any adapted shape housing a longitudinal heating cavity 10 (hereinafter also referred to as cavity) extending along a central axis or longitudinal axis Z1 defining a longitudinal direction Z.

[0121] The heating chamber 10 is delimited in a lateral direction Y orthogonal to the longitudinal direction Z by lateral walls 12 and has a tubular shape of constant (here circular) cross section (considered in a transverse plane XY orthogonal to the longitudinal direction Z).

[0122] The heating chamber 10 is provided with an opening 14 at one insertion or upper end 10 a and is adapted to receive at least a portion of an aerosol-generating article (not shown) inserted through the opening 14 .

[0123] The device 100 further comprises a heating system 20 powered by a power source 90 and configured to heat an aerosol-generating article received in the heating cavity 10 , the heating system 20 and the power source 90 being housed in the outer body 2 of the device 100 .

[0124] As shown, the heating system 20 can be an external heater comprising: a heater body 22 in the form of a longitudinal metal sleeve surrounding the heating cavity 10; and a heating element 28, such as a thick or thin film including a layer of electrically insulating material and a layer of electrically conductive material located outside or inside the heater body 22.

[0125] exist Figure 2 and Figure 3 In the particular example shown in FIG. 1 , the heater body 22 is in the shape of a cup with a lateral tubular wall 23 and a bottom wall 24 . A heating element 28 is arranged outside said heater body 22 , the lateral wall 23 here forming the lateral wall 12 of the heating chamber 10 .

[0126] like Figure 2 As shown in the figure, the heater body 22 is received in a retaining member 80, which is typically made of a high temperature resistant plastic (such as PEEK) and has a transverse base 81 orthogonal to the longitudinal direction Z of the heating chamber 10 and a retaining device 82 protruding upward from the base 81, such as a longitudinal tongue, which is configured to retain the heater body 22, for example by clamping.

[0127] Advantageously, the retaining means 82 is configured to retain the heater body 22 at a distance from the base 81 , leaving a gap between the heater body 22 and the base 81 , the function of which will be described below.

[0128] When an aerosol-generating article is inserted into the heating cavity 10 and the user actuates the device 100, the power supply 90 supplies current to the heating element 28. The heating element 28 is heated and the heat is transferred by thermal conduction to the heater body 22 and hence to the article surrounded by said heater body 22.

[0129] Upon heating, the aerosol-forming substances contained in the tobacco matrix of the article vaporize and produce a vapor which extracts nicotine and flavor components from the tobacco matrix.

[0130] Volatile compounds, aerosols, fragments of aerosol-generating articles or external dirt accumulate on the lateral walls 12 of the heating chamber 10 .

[0131] According to the invention, the aerosol-generating device 100 comprises an integrated cleaning tool 30 , which is movable in the longitudinal direction Z and is configured to wipe said contaminated material on the lateral wall 12 .

[0132] The cleaning tool 30 is provided with at least one cleaning member 40 extending laterally at the periphery of the tool 30 and configured to flexibly wipe the lateral wall 12 .

[0133] Several embodiments of the cleaning tool 30 will be described in more detail in the following description.

[0134] In the retracted position, the cleaning tool 30 forms the bottom surface of the heating chamber 10, such as Figure 1A As shown in .

[0135] The movement of the cleaning tool 30 inside the heating chamber 10 is actuated by means of an actuator 60 , for example a mechanical linear actuator of the screw-nut type.

[0136] The actuator 60 can be triggered based on a user command (for example, via a user button 92 provided on the device 100) and / or based on other parameters (for example, the time period since the last cleaning process and / or the number of suction processes and / or the degree of contamination inside the cavity and / or the temperature of the heating system and / or the charge state of the battery 90 and / or the resistance or impedance at the lateral walls of the heating cavity).

[0137] The device 100 advantageously comprises a control unit 94 , typically a microcontroller, configured to trigger the actuator 60 based on one or several parameters mentioned above.

[0138] The control unit 94 is connected to the user button 92 (if present) and the battery 90 , receives signals from the user button and the battery, and is configured to operate both the actuator 60 and the heating system 20 .

[0139] According to an advantageous arrangement, the device 100 may also be provided with at least one sensor 96 configured to measure at least one parameter representative of the degree of contamination of the heating chamber 10 and to send a corresponding signal to the control unit 94 .

[0140] At least one sensor 96 may for example be configured to measure resistance or impedance, in particular at the lateral wall 12. Fouling on the lateral wall 12 has a different resistance / impedance than the heater body 22, measuring this parameter allows estimating the degree of fouling on said lateral wall 12.

[0141] Therefore, the cleaning can be controlled in a closed loop manner according to actual needs, thereby preventing the heating chamber 10 from being cleaned too frequently or, conversely, not frequently enough.

[0142] Fig.15 A process flow chart is provided in and illustrates one possible implementation of the cleaning method according to the present invention, which operates in a closed loop:

[0143] In a first step S1 , the control unit 94 checks whether a condition for the cleaning process is satisfied, for example, whether the battery 90 is charged to at least 80% or is being charged.

[0144] In a third step S2 , a parameter representing the degree of fouling of the heating chamber 10 is measured.

[0145] In a fourth step S3 , the measurement signal is typically filtered, digitized and processed by firmware associated with the sensor 96 .

[0146] In a fifth step S4 , the degree of dirtiness estimated by the firmware is transmitted to the control unit 94 .

[0147] In a sixth step S5 , the control unit 94 activates a cleaning process based on the estimated degree of soiling.

[0148] In a seventh step S6, the user may be informed that the cleaning is complete.

[0149] As an alternative, the cleaning can also be controlled in an open loop, ie according to a calibrated procedure. In this case, the sensor 96 for evaluating the degree of contamination inside the chamber 10 can be omitted or used as a supplement.

[0150] The automatic cleaning control performed in a closed-loop or open-loop manner can also be supplemented by cleaning commands from the user.

[0151] It should be noted that the cleaning process itself can be adapted as desired: for example, the cleaning process may include moving the cleaning tool back and forth along the cavity several times, possibly at different speeds and / or at different temperatures in the heating cavity.

[0152] Figure 2 and Figure 3 , an actuator 60 according to a possible embodiment is shown. Here, the actuator 60 comprises a motor 62 and a screw 64, which can be translated along the longitudinal direction Z by actuation of the motor 62. In the example shown, the screw 64 extends along the longitudinal axis Z2, coaxial with the heating chamber 10, and the cleaning tool 30 is integral with the screw 62 (for example, fixed to the top end 64a ( Figure 1B )), which is achieved in particular by means of a threaded connection 39, which will be referred to hereinafter Figure 5 Describe in more detail.

[0153] Here, the screw 64 passes through the opening 25 formed in the bottom wall 24 of the heater body 22 and is long enough to allow the cleaning tool 30 to move up and down along the heating chamber 10. A gap 9 is required below the heating chamber 10 to receive the screw 64 in the retracted position.

[0154] Advantageously, the edge 26 of the bottom wall 24 of the heater body 22 around the screw opening 25 can be turned up to prevent dirt from falling into the inaccessible part of the device 100. An additional silicone seal 27 around the opening 25 can also be arranged on the underside of the bottom wall 24 to prevent dirt from falling out.

[0155] In this first embodiment, the motor 62 is an indirect drive and eccentric type motor (axis Z3), and the actuator 60 comprises a reduction gear 70 between the motor 62 and the screw 64 for transmitting the rotational movement to the screw 64. The reduction gear 70 comprises meshing cogwheels, here two cogwheels 71, 72, which together have an overall transmission ratio less than 1, for reducing the rotational speed and increasing the torque transmitted to the screw 64.

[0156] In the embodiment shown, the motor 62 is attached to the holder 80, in particular to the bottom side of the base 81, and the shaft 63 passing through the base 81 is integral with the first cogwheel 71 of smaller diameter. The motor 62 is protected from possible overheating due to the clearance between the heater body 22 and the base 81. The motor 62 is connected to the control unit 94 and receives power from the battery 90.

[0157] The first cogwheel 71 is fixed to the top side of the base 81 by a split pin 73 to prevent loosening. The first cogwheel 71 meshes with a second cogwheel 72 having a larger diameter, thereby transmitting the rotational movement of the motor shaft 63 to the second cogwheel 72.

[0158] The second cogwheel 72 has a gear portion 74 located on the top side of the base 81 and meshing with the first cogwheel 71, and a central shaft 75 provided with a threaded hole 76 configured to receive the screw 64 in a threaded engagement. The second cogwheel 72 forms a so-called nut of the mechanical actuator 60.

[0159] With this arrangement, rotational movement of the second cogwheel 72 causes longitudinal movement of the screw 64 , and thus of the cleaning tool 30 that is integral with the screw 64 .

[0160] In the specifically illustrated example, the central shaft 75 of the second cogwheel 72 is mounted in a through hole 83 of the base 81 .

[0161] According to an embodiment not shown, a bearing may also be overmolded onto said through hole 83 of the holder 80 in order to reduce the friction between the shaft of the cogwheel 72 and the base 81 .

[0162] A small latch 77 may be further placed below the second cogwheel 72 and the retainer 80 to secure the cogwheel 72 in a longitudinal position, such as Figure 2 and Figure 3 as shown in .

[0163] According to an embodiment not shown, the rigidity of the screw rod 64 can be further enhanced by providing an additional retainer at the bottom of the screw rod 64 .

[0164] The reduction gears (such as the cogwheels 71 , 72 ) may be made of high temperature resistant plastic (such as polyetheretherketone (PEEK)) or metal. The screw 64 may be made of metal, preferably stainless steel.

[0165] After the user presses the actuation button 92, the motor 62 starts to move the screw 64 upward. As the screw 64 rotates and moves upward, the cleaning tool 30 is pushed upward. The screw 64 is advantageously provided with a hard stop 65 at its bottom end to prevent the screw from falling if the motor 62 is not stopped in time.

[0166] refer to Figure 2 and Figure 3 The described actuator 60 should not be considered limiting, and Figure 4An actuator 60 is shown comprising a motor 62, the axis Z3 of which is aligned with the screw axis Z2. With this arrangement, the motor 62 can be a direct drive motor 62, with the nut being integral to the direct drive motor. The actuator 60 with a direct drive motor is more compact and does not require mechanical transmission elements such as gears. According to another embodiment, the motor 62 can be of the indirect drive type.

[0167] Furthermore, although in the above-described embodiment, the cleaning tool 30 is rotatably mounted in the chamber 10, which is particularly suitable for a heating chamber 10 having a circular cross section, the cleaning tool 30 may also be fixed with one degree of freedom so as to move in the longitudinal direction without rotating, particularly for a chamber having a non-circular cross section. In this case, the screw 64 may be fixed in the longitudinal direction Z1, and the cleaning tool 30 may be configured to move along the screw when the screw 64 rotates. In particular, the screw may be offset relative to the longitudinal axis Z1 of the heating chamber 10. Alternatively, according to Fig.14 In another embodiment shown in , the tool 30 can be supported in a freely rotatable manner at the end of a longitudinally movable screw, for example by at least one ball bearing 54. In the example shown, the ball bearing 54 comprises a top support element 55 forming a hub 56 and integral with the top end 64a of the screw 64, and a shaft 57 integral with the tool body 31. The reverse arrangement is also possible.

[0168] Now refer to Figures 5 to 13 An example of the cleaning tool 30 and the cleaning member 40 thereof is described.

[0169] The cleaning tool 30 typically has a central cleaning body 31 and one or several cleaning members protruding from the periphery of the cleaning body 31 .

[0170] The tool body 31 has a body axis Z4 which, after assembly, is parallel to the longitudinal axis Z1 of the heating chamber 10 and is preferably aligned therewith.

[0171] like Figures 5 to 7 As mentioned above Fig.14 As shown separately in FIGS. 1 and 1 , the cleaning member 40 may be removably attached to the tool body 31 .

[0172] In these embodiments, cleaning member 40 may form a distal portion of a cleaning module 46 that is attached to body 31 at its proximal end.

[0173] For example, in Figure 5 In the embodiment of FIG. 3 , the body 31 comprises an upper body portion 32 and a lower body portion 34 aligned along said axis Z4.

[0174] The lower body portion 34 is securely attached to the top end 64a of the screw 64 by means of a threaded connection 39, the arrangement being particularly similar to that described above with reference to Figure 2 and Figure 3 Actuators of the type described are compatible. However, as mentioned above, this should not be seen as limiting.

[0175] In this example, the upper and lower body portions 32, 34 are configured to be threadably secured to one another.

[0176] The lower body portion 34 is provided, on an upper side opposite the threaded connection 39 , with a threaded hole 35 and a first contact surface 34 a which is substantially orthogonal to the body axis Z4 .

[0177] On the other hand, the upper body part 32 is provided at its lower side with a protruding threaded rod 33, which is configured to threadably cooperate with a corresponding hole 35 of the lower body part 34. The upper body part 32 is further provided with a second contact surface 32a surrounding the rod 33 and here substantially orthogonal to the body axis Z4.

[0178] When the two parts 32, 34 are firmly fixed to each other, the first and second contact surfaces 32a, 34a act as clamping claws for fixing the cleaning module(s) 46 therebetween. If necessary, the cleaning module(s) can be easily disassembled by disconnecting the upper and lower body parts 32, 34. As an alternative, any other means suitable for removably fixing the cleaning member to the cleaning body can be envisaged.

[0179] It has to be mentioned that the removable arrangement of the cleaning member 40 is also not restrictive, and the cleaning member 40 and the cleaning body 31 may be integrally formed (molded or injection molded), wherein the cleaning member 40 protrudes laterally from the central cleaning body 31. For example, Fig.13 A cleaning tool 30 is shown having a non-detachable cleaning member 40 .

[0180] like Figure 5 and Figure 6 As illustrated in FIG, the cleaning tool 30 advantageously comprises at least one air channel 38 arranged on both the lateral sides and the upper side thereof.

[0181] The air passages 38 are configured to allow air to flow from the lateral sides of the cleaning tool 30 to its upper side. Thus, the cleaning tool 30 allows air to flow to the end of the tobacco rod, which is necessary to improve the efficiency of smoking. The number or arrangement of the (one or more) air passages 38 on the upper side of the tool body 31 can be adjusted as needed. For example, Figure 4 In the embodiment, the body 31 is provided with four intersecting air passages 38 forming a cross. Figure 6In the embodiment, the body 31 is provided with eight intersecting air passages 38, wherein two adjacent passages form an angle of about 45°.

[0182] exist Figure 7 and Figure 8 In the embodiment shown in , the cleaning tool 30 includes several cleaning members 40 that are closely juxtaposed adjacent to each other around the entire perimeter of the cleaning tool.

[0183] The juxtaposed cleaning members 40 are narrow elongated beams forming the teeth of a cleaning comb 42, wherein each cleaning member 40 has a main axis Z5 extending in a lateral direction.

[0184] The length l of each cleaning member 40 protruding laterally from the cleaning body 31 (measured along its main axis Z5 ) is preferably between 0.1 mm and 1 mm.

[0185] The cross section of the cleaning member 40 orthogonal to its main axis Z5 may be circular, rectangular or any other shape suitable for ensuring flexibility taking into account the length l of said cleaning member.

[0186] The thickness h (measured in the longitudinal direction) of each cleaning member 40 may preferably be between 0.01 mm and 0.5 mm, preferably between 0.05 mm and 0.2 mm.

[0187] More specifically, the maximum dimension of the cleaning member 40 (measured on a plane orthogonal to its main axis Z5) may be between 0.01 mm and 0.5 mm, preferably between 0.05 mm and 0.2 mm.

[0188] As an example, each cleaning member may be inscribed in an angular sector having an angle θ1 around the longitudinal axis Z1 (body axis Z4 ) smaller than 1°, or even smaller than 0.5°.

[0189] exist Figure 5 In the removable arrangement shown in FIG. 4 , each cleaning member 40 may be part of a separate element or module 46 that is attached to the tool body 31 independently of the other elements or modules.

[0190] However, according to a preferred embodiment, a plurality of teeth 40 , in particular all teeth 40 , may be connected together to form a single-piece cleaning module 46 .

[0191] Such a cleaning module may, for example, be formed from a disc-shaped sheet of metal (eg stainless steel or titanium) perforated in the centre and etched at its periphery to form the teeth 40 .

[0192] like Figure 8As shown in , the cleaning member 40 can also be coated at least partially, particularly at its free end 40a, to enhance the wiping effect or otherwise improve the cleaning effect. The coating 44 can be based on or made of PTFE or silicon or any other suitable material. The coating can be applied, for example, by dipping, dipping and centrifuging, or other coating techniques.

[0193] Fig. 9 Another embodiment is shown, in which the cleaning module 46 is formed by a folded wire 44, in particular a folded metal wire, each outwardly directed bend of the wire forming a cleaning member 40 at the periphery of the cleaning tool 30. The cleaning members 40 thus formed are closely juxtaposed, forming a similar Figure 7 The cleaning comb 42 is configured to brush the lateral wall 12 of the heating chamber 10.

[0194] Fig.10 A cleaning tool 30 according to yet another embodiment is shown, wherein the cleaning member 40 is a flexible disc-shaped scraper having a central hole to allow the fixing rod 33 to pass therethrough.

[0195] Although the preceding figures illustrate a single cleaning layer L including one cleaning zone 50 extending around the entire cleaning tool 30, this should not be viewed as limiting.

[0196] Specifically, if Fig.11 As shown in , the cleaning tool 30 may also comprise at its periphery and when viewed in transverse projection at least one free zone 52 without cleaning members 40, the or each free zone 52 extending over an angular sector having an angle θ2 of at least 35°, preferably at least 70° around the longitudinal axis.

[0197] More specifically, the cleaning tool 30 may include alternating cleaning zones 50 and free zones 52 along its perimeter.

[0198] In this case, the entire lateral wall 12 can be lightly swept by the rotation of the cleaning tool 30. The thickness of the cleaning zone 50 in the longitudinal direction Z should be designed according to the pitch of the screw thread.

[0199] As illustrated, the cleaning member 40 or a plurality of juxtaposed cleaning members 40 are typically defined in a transverse plane or in a plane inclined relative to the transverse plane to form a so-called cleaning layer L. As shown in FIG.

[0200] Although the cleaning tool described above includes a single cleaning layer L, the cleaning tool 30 may also include several cleaning layers L1, L2 stacked in the longitudinal direction, each layer L1, L2 including one or several cleaning members 40 and / or zones 50, such as Fig.12 As shown in .

[0201] The superimposed cleaning layers L1, L2 may be stacked directly on top of each other to provide a thicker cleaning zone(s) 50, or as Fig.12 As shown in FIG. 4 , different cleaning layers may be separated by spacers 48 .

[0202] Fig.13 A cleaning tool 30 according to another embodiment is shown.

[0203] The tool 30 is here provided with a collection cup 37 located below the cleaning zone(s) 50 to collect debris brushed off by the cleaning member(s) 40 as the tool 30 moves in the chamber 10. The purpose is to avoid the accumulation of debris in the bottom of the heating chamber 10 over time and to facilitate its discharge by tilting the device 100 downwards, which is preferably done when the screw 64 is fully extended in the heating chamber 10 (i.e. the tool 30 is in its most extended position, as shown in FIG. Figure 1B The cleaning member 40 and the collection cup 37 may be integrally formed (molded or injection molded) with the tool body 31, as shown in the drawings. However, as an alternative, they may be removably attached together and / or fixed to the tool body 31 in any suitable manner (e.g., by press fit / screw / magnet engagement).

Claims

1. An aerosol generating device (100), comprising: - a heating chamber (10) extending in a longitudinal direction (Z) along a longitudinal axis (Z1) and delimited by lateral walls (12) in a lateral direction (X) orthogonal to said longitudinal direction (Z), said heating chamber (10) being provided with an opening (14) at one upper end (10a) and being suitable for receiving at least a portion of an aerosol-generating article inserted through said opening (14), and - a heating system (20) for heating the aerosol-generating article (1) received in the heating chamber (10), The aerosol generating device (100) is characterized in that the aerosol generating device further comprises an integrated cleaning tool (30), the integrated cleaning tool being configured to move longitudinally within the heating chamber (10) when the actuator (60) is actuated, and the integrated cleaning tool comprising at least one cleaning member (40), the at least one cleaning member being configured to flexibly wipe the lateral wall (12) of the heating chamber (10) when moving along the heating chamber (10).

2. The aerosol generating device (100) according to claim 1, wherein: The integrated cleaning tool (30) comprises a plurality of cleaning members (40) that are capable of deforming independently of one another.

3. The aerosol generating device (100) according to claim 1 or 2, wherein: The integrated cleaning tool (30) comprises a plurality of spaced-apart cleaning members (40).

4. The aerosol generating device (100) according to any one of claims 1 to 3, wherein: The cleaning tool (30) includes a plurality of juxtaposed cleaning members (40) to form a cleaning comb (42).

5. The aerosol generating device (100) according to any one of claims 1 to 4, wherein: The cleaning member (40) is at least partially coated, for example, with PTFE or silicon.

6. The aerosol generating device (100) according to any one of claims 1 to 5, wherein: At least one cleaning member (40) is a flexible scraper.

7. The aerosol generating device (100) according to any one of claims 1 to 6, wherein: The at least one cleaning member has a length measured in the lateral direction of between 0.1 mm and 1 mm.

8. The aerosol generating device (100) according to any one of claims 1 to 7, wherein: The thickness of the at least one cleaning member (40), measured along the longitudinal direction (Z), is between 0.01 mm and 0.5 mm, still more preferably between 0.05 mm and 0.2 mm.

9. The aerosol generating device (100) according to any one of claims 1 to 8, wherein: The cleaning tool (30) comprises at its periphery at least one cleaning zone (50) having at least one cleaning member (40) and at least one free zone (52), wherein the or each free zone (52) extends over an angular sector of at least 35°, preferably at least 70°, around the longitudinal axis (Z).

10. The aerosol generating device (100) according to any one of claims 1 to 9, wherein: The cleaning tool (30) comprises at least one air channel (38) arranged on both its lateral sides and its upper side.

11. An aerosol generating device (100) according to any one of claims 1 to 10, wherein: The cleaning tool (30) comprises a tool body (31, 32, 34), and the at least one cleaning member (40) is detachably fixed to the tool body (31, 32, 34).

12. The aerosol generating device (100) according to claim 11, wherein: The cleaning tool (30) comprises at least one one-piece cleaning module (46) comprising a plurality of cleaning components (40) and being detachably fixed to the tool body (31).

13. The aerosol generating device (100) according to claim 12, wherein: The cleaning module (46) is formed by a folded wire (44), the folds of the wire forming a cleaning member (40).

14. An aerosol generating device (100) according to any one of claims 1 to 13, wherein: The actuator (60) is a mechanical linear actuator comprising a screw (64) extending along the longitudinal direction (Z) and a nut (75) threadedly engaged with the screw (64).

15. The aerosol generating device (100) according to any one of claims 1 to 14, further comprising a control unit (94), which is used to control one or several parameters, in particular to control one or several parameters representing the degree of contamination of the heating chamber (10), and to actuate the actuator based on the (one or several) parameters.

16. An aerosol generating device (100) according to claim 15, further comprising at least one sensor (96), the at least one sensor being configured to measure at least one parameter representing a degree of contamination of the heating chamber (10) and to send a corresponding signal to the control unit (94).

17. An aerosol generating device (100) according to any one of claims 1 to 16, wherein: The cleaning tool (30) is configured to be stored in a retracted position at a bottom end (10b) of the heating chamber (10) when the actuator (60) is at rest.

18. A method for cleaning an aerosol generating device (100) according to any one of claims 1 to 17, comprising: The actuator (60) is actuated to achieve longitudinal movement of the cleaning tool (30) inside the heating chamber (10).

19. The cleaning method according to claim 18, comprising: At least one parameter indicative of the degree of contamination of the heating chamber (10) is measured in a closed-loop manner, and the actuator (60) is actuated based on the parameter.

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