EP4602938A1

EP4602938A1 - Aerosol generating apparatus

Info

Publication number: EP4602938A1
Application number: EP24157799.8A
Authority: EP
Inventors: designation of the inventor has not yet been filed The
Original assignee: Imperial Tobacco Ltd United Kingdom
Current assignee: Imperial Tobacco Ltd United Kingdom
Priority date: 2024-02-15
Filing date: 2024-02-15
Publication date: 2025-08-20

Abstract

An aerosol generating apparatus (1) is provided comprising : a cavity (101) arranged within the apparatus (1) for receiving a consumable (70) aligned along an axis of the cavity (101), an aerosol generating unit (4) within the cavity (101) configured to generate an aerosol from the consumable (70) when axially received in the cavity (101), and a rotatable closure member (105) arranged at a mouth of the cavity (101) to control access of the consumable (70) to the cavity (101). The closure member (105) has a bore (107) extending from an entry (108) at one side of the closure member (105) to an exit (109) at an opposite side of the closure member (105). The closure member (105) is also rotatable about a rotation axis (R) between a first position in which the bore (107) is aligned with the axis of the cavity (101) such that a consumable (70) inserted through the bore (107) is further insertable into the cavity (101) for axial reception therein, and a second position in which the bore (107) is misaligned with the axis of the cavity (101) such that the closure member (105) blocks the mouth of the cavity (101) and prevents reception of a consumable (70) therein.

Description

FIELD

The present disclosure relates to an aerosol generating apparatus.

BACKGROUND

A conventional aerosol generating apparatus may comprise a power supply, and a heating element that is driven by the power supply for heating consumable material of a consumable. By heating the consumable material, aerosol is generated which is intended to be inhaled by a user of the aerosol generating apparatus. In order to engage the consumable material with the heating element, the consumable is inserted into a consumable cavity containing the heating element. By inserting the consumable into the consumable cavity, the consumable material is brought into proximity with the heating element, so that heat generated by the heating element increases the temperature in the consumable material to generate the aerosol.
A drawback with known aerosol generating apparatuses is that access to the consumable cavity, e.g. via an opening, and thereby access to the heating element, is maintained even when no consumable is inserted. Therefore, it is possible for foreign objects which are not intended to be within the consumable cavity to accidentally enter the cavity. This may prevent or limit insertion of a consumable into the cavity, which can render the aerosol generating apparatus inoperable. Further, the presence of the foreign object in the cavity may damage parts of the aerosol generating apparatus, especially the heating element. Moreover, the foreign object could potentially, depending on its composition and structure, generate an aerosol component which is not suitable to be inhaled, and/or could react to the heat in an undesirable manner, such as by melting or ignition.
Alternative forms of aerosol generating apparatuses are also known which, rather than a heating element, have a different type of powered unit, such as an ultrasonic system, for generating the aerosol from the consumable. However, similar problems of undesirable foreign object incursion into the consumable cavity remain.
In spite of the effort already invested in the development of aerosol generating apparatuses further improvements are desirable.

SUMMARY

In general terms, the present disclosure provides an aerosol generating apparatus, comprising: a cavity arranged within the apparatus for receiving a consumable aligned along an axis of the cavity, an aerosol generating unit (such as a heating system) within the cavity configured to generate an aerosol from the consumable when axially received in the cavity, and a rotatable closure member arranged at a mouth of the cavity to control access of the consumable to the cavity. The closure member has a bore extending from an entry at one side of the closure member to an exit at an opposite side of the closure member. The closure member is rotatable about a rotation axis between a first position in which the bore is aligned with the axis of the cavity such that a consumable inserted through the bore is further insertable into the cavity for axial reception therein, and a second position in which the bore is misaligned with the axis of the cavity such that the closure member blocks the mouth of the cavity and prevents reception of a consumable therein.
Thus by rotating the rotatable element to the second position, access to the consumable cavity can be prevented when the aerosol generating apparatus is not in use. In this way, not just consumables, but foreign objects which are not intended to be within the cavity can be prevented from entering. Conveniently, the closure member can be rotated by a digit of a user directly interacting with a surface of the closure member to turn the member.
Examples of the aerosol generating apparatus described above in general terms may further comprise a housing, the cavity and the closure member being provided inside the housing and the mouth of the cavity being formed by a window in the housing. In these examples, in the first position, the entry to the bore may be located within the window and, in the second position, either or both of the entry to and the exit from the bore may be at least partially covered by the housing.
Additionally or alternatively, examples of the aerosol generating apparatus described above in general terms may further comprise a chassis that retains the closure member at a predetermined location in the apparatus such that the closure member is positioned at the mouth of the cavity with the closure member rotatable between the first position and the second position. The chassis may also define the cavity, e.g. by providing a surrounding wall of the cavity.

Innovation A

In a first aspect of the aerosol generating apparatus described earlier in general terms, the closure member is substantially axisymmetric about the rotation axis, a portion of the surface of the closure member extending as an annular belt circumferentially around the closure member, with to either side of the annular belt the closure member having side surfaces centred on and substantially perpendicular to the rotation axis, wherein the annular belt contains the entry to the bore, and the surface of the closure member in the annular belt curves convexly in both the circumferential and polar directions of the closure member.
Thus the annular belt provides a bi-curved surface which can be both aesthetically pleasing and an effective surface for manual operation of the closure member by a user. On the other hand, the side surfaces can provide convenient locations for mounting structures and for mechanisms controlling the rotational movement of the closure member, as discussed in more detail below.
The closure member may be substantially shaped as a flattened spheroid, the rotation axis extending along the minor axis of the spheroid and the bore extending along a major diameter of the spheroid such that the annular belt extends equatorially around the spheroid.
When the aerosol generating apparatus further comprises the housing, as the closure member is rotated between the first and second positions, progressively different parts of the annular belt are exposed externally through the window, while the side surfaces of the closure member may remain completely covered by the housing.
The perimeter of the entry to the bore can be chamfered or rounded to guide insertion of a consumable into the bore without snagging on the perimeter.

Innovation B

Optionally, the aerosol generating apparatus of the first aspect comprises a bistability mechanism which is configured to operate on the closure member such that at all rotational positions of the closure member from the first position to a position intermediate the first and second positions the closure member is biased towards the first position, and at all rotational positions of the closure member from the second position to the intermediate position the closure member is biased towards the second position; whereby, to rotate the closure member from a starting one of the first and second positions to a destination one of the other of the first and second positions, a torque is applied against the respective bias urging the closure member to the start position until the intermediate position is reached whereupon the opposite bias carries the closure member to the destination position. Indeed, more generally, in a second aspect of the aerosol generating apparatus described earlier in general terms, the apparatus comprises a bistability mechanism which is configured to operate on the closure member such that at all rotational positions of the closure member from the first position to a position intermediate the first and second positions the closure member is biased towards the first position, and at all rotational positions of the closure member from the second position to the intermediate position the closure member is biased towards the second position; whereby, to rotate the closure member from a starting one of the first and second positions to a destination one of the other of the first and second positions, a torque is applied against the respective bias urging the closure member to the start position until the intermediate position is reached whereupon the opposite bias carries the closure member to the destination position.
Thus advantageously, under the operation of the bistability mechanism, the closure member is bistable in that if torque is applied to move it to any position between the first and second positions, when that torque is released it will automatically move to the first position and then remain in that position if the release position is between the first position and the intermediate position, but will automatically move to the second position and then remain in that position if the release position is between the second position and the intermediate position.
Conveniently, the bistability mechanism may be a spring. This can provide a heat resistant, quiet and reliable action. However other bistability mechanisms are also possible, such as magnet-based mechanisms.
When the aerosol generating apparatus is the apparatus of the first aspect, the bistability mechanism may be mounted to one of the side surfaces. In this way, when the aerosol generating apparatus further comprises the housing, the bistability mechanism can conveniently be protected under the housing and hidden from external view.
The aerosol generating apparatus may further comprise a stop mechanism which limits rotational movement of the closure member to rotation between the first and second positions. When the aerosol generating apparatus is the apparatus of the first aspect, the stop mechanism may be mounted to one of the side surfaces, e.g. on the other side of the closure member to the bistability mechanism.

Innovation C

Optionally, in the aerosol generating apparatus of any of the previous aspects, the rotation axis extends perpendicularly to the axis of the cavity, and the closure member is configured to be rotated by a predetermined angle (which may be greater than 45° and/or may be up to 90°, typically being equal to 90°) about the rotation axis to rotate between the first position and the second position, and a top surface of the closure member is exposed externally of the apparatus at the mouth of the cavity; wherein the portion of the surface of the closure member forming the externally exposed top surface in the first position contains the entry to the bore, and the portion of the surface of the closure member forming the externally exposed top surface in the second position contains no part of the entry to the bore. Indeed, more generally, in a third aspect of the aerosol generating apparatus described earlier in general terms, the rotation axis extends perpendicularly to the axis of the cavity, and the closure member is configured to be rotated by a predetermined angle (which may be greater than 45° and/or may be up to 90°, typically being equal 90°) about the rotation axis to rotate between the first position and the second position, and a top surface of the closure member is exposed externally of the apparatus at the mouth of the cavity; wherein the portion of the surface of the closure member forming the externally exposed top surface in the first position contains the entry to the bore, and the portion of the surface of the closure member forming the externally exposed top surface in the second position contains no part of the entry to the bore.
In this way, a pair of portions of the surface of the closure member are externally exposed to the user of the apparatus, but these portions can be kept visually and functionally distinct, i.e. one containing the entry to the bore and one not.
The portion of the surface of the closure member forming the externally exposed top surface in the second position may be smoothly and continuously curved in all directions.
When the apparatus is an apparatus of the first aspect, the top surface may be contained within the annular belt.
A bottom surface of the closure member may be internally exposed to the cavity at the underside of the closure member; wherein the portion of the surface of the closure member forming the internally exposed bottom surface in the first position contains the exit from the bore, and the portion of the surface of the closure member forming the internally exposed bottom surface in the second position contains no part of the exit from the bore. In this way, another pair of portions of the surface of the closure member can be kept functionally distinct, i.e. one containing the exit from the bore and one not. Combined with the pair of portions externally exposed at the top surface, it is then possible to define four functionally distinct and contiguous sectors, or quadrants, of the surface of the closure member.
When the aerosol generating unit is a heating system, the portion of the surface of the closure member forming the internally exposed bottom surface in the second position may carry a heat shield (e.g. a reflective surface layer) to reduce transfer of heat from the heating system into the closure member. For example, the heat shield can be carried in a recess formed in the surface of the closure member. Indeed, more generally, the portion of the surface of the closure member forming the internally exposed bottom surface in the second position may have a recess formed in the surface of the closure member, i.e. even without a heat shield. The recess can distance the surface of the closure member from the heat of the heating system after an activation.
When the apparatus is an apparatus of the first aspect, the bottom surface may be contained within the annular belt.

Innovation D

Optionally, in examples of the aerosol generating apparatus of any of the previous aspects which further comprise the housing, the entry and the exit are both completely covered by the housing when the closure member is in the second position. Indeed, more generally, in a fourth aspect of the aerosol generating apparatus described earlier in general terms which further comprises the housing, the entry and the exit are both completely covered by the housing when the closure member is in the second position.
In this way a visually pleasing portion of the surface of the closure member can be externally exposed to a user of the apparatus in the second position. In addition, as the entry and the exit are both completely covered, foreign objects can be prevented from entering the bore.

Innovation E

Optionally, in the aerosol generating apparatus of any of the previous aspects, the aerosol generating unit is a heating system, and the closure member is formed of a material having a thermal conductivity of at least 100 Wm^-1K^-1 (and preferably at least 200 Wm^-1K^-1). Indeed, more generally, in a sixth aspect of the aerosol generating apparatus described earlier in general terms, the aerosol generating unit is a heating system, and the closure member is formed of a material having a thermal conductivity of at least 100 Wm^-1K^-1 (and preferably at least 200 Wm^-1K^-1). The thermal conductivity may be measured according to ISO 8302.
By forming the closure member of a material having a thermal conductivity of at least 100 Wm^-1K^-1, the closure member can act as an effective heat sink for waste heat produced by the heating system, generally reducing the temperature of the aerosol delivered to the user and helping to produce a consistent user experience over successive apparatus activations. Also, after an activation, the relatively high thermal conductivity rapidly reduces the surface temperature of the closure member, allowing the apparatus to be safely pocketed by the user.
For example, the closure member may be formed of aluminium alloy, such as Al 6063 which has a thermal conductivity of about 210 Wm^-1K^-1.
When the aerosol generating apparatus further comprises the chassis, the thermal conductivity of the material forming the closure member may be substantially higher than the thermal conductivity of the material forming the chassis, e.g. at least 100 or 1000 times higher. Typically, the chassis may be formed of a plastic material having e.g. a thermal conductivity in the range 0.1 to 0.5 Wm^-1K^-1. The chassis can thus function as an insulator, while the closure member can function as a heat sink.

Innovation F

Optionally, in examples of the aerosol generating apparatus of any of the previous aspects which further comprise the chassis, the closure member and the chassis are configured such that, to assemble the apparatus, the closure member is slid into the chassis to arrive at the predetermined location, the closure member and the chassis cooperating to produce a snap fit on arrival of the closure member that retains the closure member at the predetermined location. Indeed, more generally, in a fifth aspect of the aerosol generating apparatus described earlier in general terms which further comprises the chassis, the closure member and the chassis are configured such that, to assemble the apparatus, the closure member is slid into the chassis to arrive at the predetermined location, the closure member and the chassis cooperating to produce a snap fit on arrival of the closure member that retains the closure member at the predetermined location.
In this way, the closure member can be quickly and securely assembled into the apparatus.
The closure member may have a pair of axle projections on opposite sides of the closure member and centred on the rotation axis, the axle projections being received in respective holes provided by the chassis on opposite sides of the closure member to form a pair of journal bearings such that the closure member is rotatable between the first position and the second position. For example, the holes may be formed in respective walls of the chassis, the walls being resiliently flexible to provide the snap fit on arrival of the axle projections in the holes when the closure member is slid into the chassis on assembly. Conveniently, each wall may have an angled ramp surface at a leading edge of the wall which makes first contact with the respective axle projection as the closure member is slid into the chassis on assembly, wherein the axle projections press against the ramp surfaces as the closure member is further slid into the chassis to gradually flex the walls apart. When the apparatus is an apparatus of the first aspect, each axle projection may be provided by a respective one of the side surfaces of the closure member.
The preceding summary is provided for purposes of summarizing some examples to provide a basic understanding of aspects of the subject matter described herein. Accordingly, the above-described features should not be construed to narrow the scope or spirit of the subject matter described herein in any way. Moreover, the above and/or proceeding examples may be combined in any suitable combination to provide further examples, except where such a combination is clearly impermissible or expressly avoided. Other features, aspects, and advantages of the subject matter described herein will become apparent from the following text and the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES

Aspects, features and advantages of the present disclosure will become apparent from the following description of examples in reference to the appended drawings in which like numerals denote like elements.

Fig. 1 is a block system diagram showing an example aerosol generating apparatus.
Fig. 2 is a block system diagram showing an example implementation of the apparatus of Fig. 1, where the aerosol generating apparatus is configured to generate aerosol from a solid precursor.
Fig. 3 is a schematic diagram showing an example implementation of the apparatus of Fig. 2.
Fig. 4A shows a perspective view of a device body of an aerosol generating apparatus with a rotatable closure member of the body in a first position allowing a consumable to be inserted into the body.
Fig. 4B shows the perspective view of Fig. 4A but with the closure member in a second position preventing a consumable from being inserted into the body.
Fig. 5A shows a longitudinal cross-sectional view corresponding to the perspective view of Fig. 4A.
Fig. 5B shows a longitudinal cross-sectional view corresponding to the perspective view of Fig. 4B.
Fig. 6A shows a perspective view of a chassis of the device body with the closure member in the first position.
Fig. 6B shows the perspective view of Fig. 6B but with the closure member in the second position.
Fig. 7A shows a longitudinal cross-sectional view corresponding to the perspective view of Fig. 6A.
Fig. 7B shows a longitudinal cross-sectional view corresponding to the perspective view of Fig. 6B.
Fig. 8A shows a perspective view of a first side of the closure member.
Fig. 8B shows a different perspective view of the first side of the closure member.
Fig. 8C shows an end view of the closure member.
Fig. 8D shows a plan view of a second side of the closure member.
Fig. 8E shows a plan view of the first side of the closure member.
Fig. 8F shows a cross-sectional view of the closure member on plane A-A.
Fig. 8G shows a partial cross-sectional view of the closure member on plane B-B.
Fig. 9A shows a side view of the top of the device body with its housing removed and the closure member in the first position.
Fig. 9B shows a side view of the top of the device body with its housing removed and the closure member in the second position.
Fig. 10A shows a perspective view of a first side of the chassis.
Fig. 10B shows a longitudinal cross-section of the chassis on the perspective view of Fig. 10A, and reveals the chassis inner surface facing the second side of the closure member.
Fig. 10C shows a perspective view of a second side of the chassis.
Fig. 10D shows a longitudinal cross-section of the chassis on the perspective view of Fig. 10C, and reveals the chassis inner surface facing the first side of the closure member.
Fig. 11A shows the plan view of the closure member of Fig. 8D superimposed with dashed lines demarcating quadrants Q1 to Q4.
Fig. 11B shows the plan view of the closure member of Fig. 8E superimposed with dashed lines demarcating the quadrants Q1 to Q4.
Fig. 12A shows perspective views of the first side of the chassis and the first side of the closure member as the closure member is offered for assembly into the chassis.
Fig. 12B shows a longitudinal cross-section of the chassis and the closure member as the closure member is offered for assembly into the chassis.
Fig. 12C is a close up of the part of Fig. 12B enclosed by a dashed rectangle.
Fig. 12D shows the longitudinal cross-section of Fig. 12B after assembly of the chassis and the closure member.

DETAILED DESCRIPTION OF EMBODIMENTS

Before describing several examples implementing the present disclosure, it is to be understood that the present disclosure is not limited by specific construction details or process steps set forth in the following description and accompanying drawings. Rather, it will be apparent to those skilled in the art having the benefit of the present disclosure that the systems, apparatuses and/or methods described herein could be embodied differently and/or be practiced or carried out in various alternative ways.
Unless otherwise defined herein, scientific and technical terms used in connection with the presently disclosed inventive concept(s) shall have the meanings that are commonly understood by those of ordinary skill in the art, and known techniques and procedures may be performed according to conventional methods well known in the art and as described in various general and more specific references that may be cited and discussed in the present specification.
Any patents, published patent applications, and non-patent publications mentioned in the specification are hereby incorporated by reference in their entirety.
All examples implementing the present disclosure can be made and executed without undue experimentation in light of the present disclosure. While particular examples have been described, it will be apparent to those of skill in the art that variations may be applied to the systems, apparatus, and/or methods and in the steps or in the sequence of steps of the methods described herein without departing from the concept, spirit, and scope of the inventive concept(s). All such similar substitutions and modifications apparent to those skilled in the art are deemed to be within the spirit, scope, and concept of the inventive concept(s) as defined by the appended claims.
The use of the term "a" or "an" in the claims and/or the specification may mean "one," as well as "one or more," "at least one," and "one or more than one." As such, the terms "a," "an," and "the," as well as all singular terms, include plural referents unless the context clearly indicates otherwise. Likewise, plural terms shall include the singular unless otherwise required by context.
The use of the term "or" in the present disclosure (including the claims) is used to mean an inclusive "and/or" unless explicitly indicated to refer to alternatives only or unless the alternatives are mutually exclusive. For example, a condition "A or B" is satisfied by any of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).
As used in this specification and claim(s), the words "comprising, "having," "including," or "containing" (and any forms thereof, such as "comprise" and "comprises," "have" and "has," "includes" and "include," or "contains" and "contain," respectively) are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.
Unless otherwise explicitly stated as incompatible, or the physics or otherwise of the embodiments, examples, or claims prevent such a combination, the features of examples disclosed herein, and of the claims, may be integrated together in any suitable arrangement, especially ones where there is a beneficial effect in doing so. This is not limited to only any specified benefit, and instead may arise from an "ex post facto" benefit. This is to say that the combination of features is not limited by the described forms, particularly the form (e.g. numbering) of example(s), embodiment(s), or dependency of claim(s). Moreover, this also applies to the phrase "in one embodiment," "according to an embodiment," and the like, which are merely a stylistic form of wording and are not to be construed as limiting the following features to a separate embodiment to all other instances of the same or similar wording. This is to say, a reference to 'an,' 'one,' or 'some' embodiment(s) may be a reference to any one or more, and/or all embodiments, or combination(s) thereof, disclosed. Also, similarly, the reference to "the" embodiment may not be limited to the immediately preceding embodiment. Further, all references to one or more embodiments or examples are to be construed as non-limiting to the claims.
The present disclosure may be better understood in view of the following explanations, wherein the terms used that are separated by "or" may be used interchangeably:
As used herein, an "aerosol generating apparatus" (or "electronic(e)-cigarette") may be an apparatus configured to deliver an aerosol to a user for inhalation by the user. The apparatus may additionally/alternatively be referred to as a "smoking substitute apparatus", if it is intended to be used instead of a conventional combustible smoking article. As used herein a combustible "smoking article" may refer to a cigarette, cigar, pipe or other article, that produces smoke (an aerosol comprising solid particulates and gas) via heating above the thermal decomposition temperature (typically by combustion and/or pyrolysis). An aerosol generated by the apparatus may comprise an aerosol with particle sizes of 0.2 - 7 microns, or less than 10 microns, or less than 7 microns. This particle size may be achieved by control of one or more of: heater temperature; cooling rate as the vapour condenses to an aerosol; flow properties including turbulence and velocity. The generation of aerosol by the aerosol generating apparatus may be controlled by an input device. The input device may be configured to be user-activated, and may for example include or take the form of an actuator (e.g. actuation button) and/or an airflow sensor.
Each occurrence of the aerosol generating apparatus being caused to generate aerosol for a period of time (which may be variable) may be referred to as an "activation" of the aerosol generating apparatus. The aerosol generating apparatus may be arranged to allow an amount of aerosol delivered to a user to be varied per activation (as opposed to delivering a fixed dose of aerosol), e.g. by activating an aerosol generating unit of the apparatus for a variable amount of time, e.g. based on the strength/duration of a draw of a user through a flow path of the apparatus (to replicate an effect of smoking a conventional combustible smoking article).
The aerosol generating apparatus may be portable. As used herein, the term "portable" may refer to the apparatus being for use when held by a user.
As used herein, an "aerosol" may include a suspension of precursor, including as one or more of: solid particles; liquid droplets; gas. Said suspension may be in a gas including air. An aerosol herein may generally refer to/include a vapour. An aerosol may include one or more components of the precursor.
As used herein, a "precursor" may include one or more of a: liquid; solid; gel; loose leaf material; other substance. The precursor may be processed by an aerosol generating unit of an aerosol generating apparatus to generate an aerosol. The precursor may include one or more of: an active component; a carrier; a flavouring. The active component may include one or more of nicotine; caffeine; a cannabidiol oil; a non-pharmaceutical formulation, e.g. a formulation which is not for treatment of a disease or physiological malfunction of the human body. The active component may be carried by the carrier, which may be a liquid, including propylene glycol and/or glycerine. The term "flavouring" may refer to a component that provides a taste and/or a smell to the user. The flavouring may include one or more of: Ethylvanillin (vanilla); menthol, Isoamyl acetate (banana oil); or other. The precursor may include a substrate, e.g. reconstituted tobacco to carry one or more of the active component; a carrier; a flavouring.
As used herein, a "flow path" may refer to a path or enclosed passageway through an aerosol generating apparatus, e.g. for delivery of an aerosol to a user. The flow path may be arranged to receive aerosol from an aerosol generating unit. When referring to the flow path, upstream and downstream may be defined in respect of a direction of flow in the flow path, e.g. with an outlet being downstream of an inlet.
As used herein, a "delivery system" may be a system operative to deliver an aerosol to a user. The delivery system may include a mouthpiece and a flow path.
As used herein, a "flow" may refer to a flow in a flow path. A flow may include aerosol generated from the precursor. The flow may include air, which may be induced into the flow path via a puff by a user.
As used herein, a "puff" (or "inhale" or "draw") by a user may refer to expansion of lungs and/or oral cavity of a user to create a pressure reduction that induces flow through the flow path.
As used herein, an "aerosol generating unit" may refer to a device configured to generate an aerosol from a precursor. The aerosol generating unit may include a unit to generate a vapour directly from the precursor (e.g. a heating system or other system) or an aerosol directly from the precursor (e.g. an atomiser including an ultrasonic system, a flow expansion system operative to carry droplets of the precursor in the flow without using electrical energy or other system). A plurality of aerosol generating units to generate a plurality of aerosols (for example, from a plurality of different aerosol precursors) may be present in an aerosol generating apparatus.
As used herein, a "heating system" may refer to an arrangement of at least one heating element, which is operable to aerosolise a precursor once heated. The at least one heating element may be electrically resistive to produce heat from the flow of electrical current therethrough. The at least one heating element may be arranged as a susceptor to produce heat when penetrated by an alternating magnetic field. The heating system may be configured to heat a precursor to below 300 or 350 degrees C, including without combustion.
As used herein, a "consumable" may refer to a unit that includes a precursor. The consumable may include an aerosol generating unit, e.g. it may be arranged as a cartomizer. The consumable may include a mouthpiece. With solid material implementations of the precursor, e.g. tobacco or reconstituted tobacco formulation, the consumable may be referred to as a "stick" or "package" or "heat-not-burn consumable". In a heat-not-burn consumable, the mouthpiece may be implemented as a filter and the consumable may be arranged to carry the precursor. The consumable may be implemented as a dosage or pre-portioned amount of material, including a loose-leaf product.
As used herein "heat-not-burn" (or "HNB" or "heated precursor") may refer to the heating of a precursor, typically tobacco, without combustion, or without substantial combustion (i.e. localised combustion may be experienced of limited portions of the precursor, including of less than 5% of the total volume).
Referring to Fig. 1, an example aerosol generating apparatus 1 includes a power supply 2, for supply of electrical energy. The apparatus 1 includes an aerosol generating unit 4 that is driven by the power supply 2. The power supply 2 may include an electric power supply in the form of a battery and/or an electrical connection to an external power source. The apparatus 1 includes a precursor 6, which in use is aerosolised by the aerosol generating unit 4 to generate an aerosol. The apparatus 2 includes a delivery system 8 for delivery of the aerosol to a user.
Electrical circuitry (not shown in figure 1) may be implemented to control the interoperability of the power supply 4 and aerosol generating unit 6..
Fig. 2 shows an implementation of the apparatus 1 of Fig. 1, where the aerosol generating apparatus 1 is configured to generate aerosol by a-heat not-burn process.
In this example, the apparatus 1 includes a device body 50 and a consumable 70.
In this example, the body 50 includes the power supply 4 and a heating system 52. The heating system 54 includes at least one heating element 54. The body may additionally include any one or more of electrical circuitry 56, a memory 58, a wireless interface 60, one or more other components 62.
The electrical circuitry 56 may include a processing resource for controlling one or more operations of the body 50, e.g. based on instructions stored in the memory 58.
The wireless interface 60 may be configured to communicate wirelessly with an external (e.g. mobile) device, e.g. via Bluetooth.
The other component(s) 62 may include an actuator, one or more user interface devices configured to convey information to a user and/or a charging port, for example (see e.g. Fig. 3).
The body 50 is configured to engage with the consumable 70 such that the at least one heating element 54 of the heating system 52 penetrates into the solid precursor 6 of the consumable. In use, a user may activate the aerosol generating apparatus 1 to cause the heating system 52 of the body 50 to cause the at least one heating element 54 to heat the solid precursor 6 of the consumable (without combusting it) by conductive heat transfer, to generate an aerosol which is inhaled by the user.
Fig. 3 shows an example implementation of the aerosol generating apparatus 1 of Fig. 2.
As depicted in Fig. 3, the consumable 70 is implemented as a stick, which is engaged with the body 50 by inserting the stick into an aperture at a top end 53 of the body 50, which causes the at least one heating element 54 of the heating system 52 to penetrate into the solid precursor 6.
The consumable 70 includes the solid precursor 6 proximal to the body 50, and a filter distal to the body 50. The filter serves as the mouthpiece of the consumable 70 and thus the apparatus 1 as a whole. The solid precursor 6 may be a reconstituted tobacco formulation or a non-tobacco formulation.
In this example, the at least one heating element 54 is a rod-shaped element with a circular transverse profile. Other heating element shapes are possible, e.g. the at least one heating element may be blade-shaped (with a rectangular transverse profile) or tube-shaped (e.g. with a hollow transverse profile). In other examples, the heater may be provided to heat an outside surface of the consumable (for example a tubular heater that forms one or more walls of the cavity).
In this example, the body 50 includes a cap 51. In use the cap 51 is engaged at a top end 53 of the body 50. Although not apparent from Fig. 3, the cap 51 is moveable relative to the body 50. In particular, the cap 51 is slidable and can slide along a longitudinal axis of the body 50.
The body 50 also includes an actuator 55 on an outer surface of the body 50. In this example, the actuator 55 has the form of a button.
The body 50 also includes a user interface device configured to convey information to a user. Here, the user interface device is implemented as a plurality of lights 57, which may e.g. be configured to illuminate when the apparatus 1 is activated and/or to indicate a charging state of the power supply 4. Other user interface devices are possible, e.g. to convey information haptically or audibly to a user.
The body may also include an airflow sensor which detects airflow in the aerosol generating apparatus 1 (e.g. caused by a user inhaling through the consumable 70). This may be used to count puffs, for example.
In this example, the consumable 70 includes a flow path which transmits aerosol generated by the at least one heating element 54 to the mouthpiece of the consumable.
In this example, the aerosol generating unit 4 is provided by the above-described heating system 52 and the delivery system 8 is provided by the above-described flow path and mouthpiece of the consumable.
Figs. 4A and 4B show perspective views of a device body 50 of an aerosol generating apparatus, which may be implemented in any of the preceding examples, and Figs. 5A and 5B show longitudinal cross-sectional views through the body 50.
A housing 100 surrounds the device body 50, a cavity 101 being provided towards the top end 53 of the body 50 for receiving a stick consumable aligned along an axis of the cavity (which is also the long axis of the generally elongate body 50). A heating system 103 in the form of an electrical resistance heater pin extends upwards from the base of the cavity along the cavity axis. Electrical power for the heating element is provided by a battery 104 housed in a bottom section of the body 50.
Above the heating element 103, a closure member 105 is arranged at a mouth of the cavity 101, the mouth being formed by a window 106 in the housing 100. The closure member 105 is retained in the device body 50 by a chassis 110 contained in the housing. Fig. 6A shows a perspective view of the chassis with the closure member in the first position; Fig. 6B shows the perspective view of Fig. 6B but with the closure member in the second position; Fig. 7A shows a longitudinal cross-sectional view corresponding to the perspective view of Fig. 6A; and Fig. 7B shows a longitudinal cross-sectional view corresponding to the perspective view of Fig. 6B. A top part of the chassis 110 retains the closure member 105, while a bottom part of the chassis provides a surrounding wall 111 of the cavity 101.
A bore 107 extends through the closure member 105 from an entry 108 at one side of the member to an exit 109 at an opposite side. To control access of the consumable to the cavity, the closure member is rotatable about a rotation axis (perpendicular to the plane of the cross-section in Figs. 5A and 5B) between: a first position (shown in Figs. 4A and 5A) in which the bore is aligned with the axis of the cavity 101, the entry 108 to the bore being located within the window 106; and a second position (shown in Figs. 4B and 5B) in which the bore is misaligned by a predetermined angle (which is generally greater than 45°, being 90° in this example) with the axis of the cavity 101, the entry 108 to and the exit 109 from the bore being covered by the housing. Accordingly, in the first position, a consumable can be inserted through the bore 107, further inserted into the cavity 101 to be pierced by the heating element 103, and then heated to generate an aerosol. In the second position, the closure member 105 blocks the mouth 106 of the cavity and prevents the consumable being received therein when the apparatus is not in use. Moreover, foreign objects which are not intended to be within the cavity 101 can be prevented from entering. Conveniently, the closure member 105 can be rotated by a digit of a user pushing directly across the surface of the closure member accessible through the window 106 to apply a torque to the closure member.
Fig. 8A shows a perspective view of a first side of the closure member 105; Fig. 8B shows a different perspective view of the side of the closure member; Fig. 8C shows an end view of the closure member; Fig. 8D shows a plan view of a second side of the closure member; Fig. 8E shows a plan view of the first side of the closure member; Fig. 8F shows a cross-sectional view of the closure member on plane A-A; and Fig. 8G shows a partial cross-sectional view of the closure member on plane B-B.
Although a number of features, such as the entry 108 to and the exit 109 from the bore 107 prevent the closure member 105 from having perfect rotational symmetry, the member is substantially axisymmetric about the rotation axis R. In particular, a portion of the surface of the closure member 105 extends as an annular belt circumferentially around the closure member, this belt containing the entry 108 and typically also the exit 109. The surface of the closure member 105 in the belt curves convexly in both the circumferential and polar directions to provide a bi-curved surface. To either side of the annular belt the closure member has first and second side surfaces centred on and substantially perpendicular to the rotation axis R. Thus the closure member can be considered as a flattened spheroid, with the rotation axis R extending along the minor axis of the spheroid and the bore 107 extending along a major diameter of the spheroid such that the annular belt extends equatorially around the spheroid.
The bi-curved surface of the annular belt can be both aesthetically pleasing (both visually and tactilely) and an effective surface for manual operation of the closure member 105 by a user. As the closure member 105 is rotated between the first and second positions, progressively different parts of the annular belt are exposed externally through the window 106. On the other hand, the side surfaces, which remain completely covered by the housing 100, provide convenient locations for mounting structures and for mechanisms controlling the rotational movement of the closure member, as discussed in more detail below.
As a result of the bi-curved surface, the perimeter of the entry 108 to the bore 107 does not lie in a flat plane, but rather is curved, as seen best when viewed (Figs. 6D and 6E) along the direction of the rotation axis R. This curved profile can correspond substantially to the curvature of the pad of a human digit (e.g. thumb). As a user's thumb can thus conform comfortably to the shape of the curved profile, the profile provides a convenient feature by which a user can obtain purchase on the closure member 105 when rotating it from the first to the second position.
The perimeter of the entry 108 to the bore 107 can be chamfered or rounded to improve user interaction with the surface of the closure member 105, and also to guide insertion of a consumable into the bore without catching on the perimeter.
Fig. 9A shows a side view of the top of the device body with its housing removed and the closure member in the first position; and Fig. 9B shows a side view of the top of the device body with its housing removed and the closure member in the second position. Fig. 10A shows a perspective view of a first side of the chassis; Fig. 10B shows a longitudinal cross-section of the chassis on the perspective view of Fig. 10A, and reveals the chassis inner surface facing the second side of the closure member; Fig. 10C shows a perspective view of a second side of the chassis; and Fig. 10D shows a longitudinal cross-section of the chassis on the perspective view of Fig. 10C, and reveals the chassis inner surface facing the first side of the closure member.
To control rotational movement of the closure member 105 between the first and second positions, the device body 50 has a bistability mechanism in form of spring 112 which is configured to operate on the closure member.
The first and second positions of the rotatable closure member 105 are defined by hard stops limiting the rotation of the closure member to the predetermined angle, which in this example is 90°. More particularly, a first recess 113 (shown in Fig. 8E) occupies a sector of the first side of the closure member 105. As shown in Figs. 10C and 10D, an inward protrusion 119 from the chassis 110 projects into the recess. This protrusion sweeps through a 90° track in the first recess as the closure member is rotated. The rotation is stopped at one end of the track when the protrusion arrives at and buts against one of the radially extending walls of the first recess 113, and is stopped at the other end when the protrusion arrives at and buts against the other radially extending wall of the first recess.
The spring 112 is located in a second recess 114 (shown in Fig. 8D) formed in the second side of the closure member 105. One end of the spring is fixed to the closure member by a pin 115 inserted into a through hole 116 running between the first and second recess. The other end of the spring is secured to a boss 117 (shown in Figs. 9A, 9B and 10C) formed on the chassis 110.
The spring 112 is maintained under load at both the first and second positions, and as the closure member 105 rotates from the first to the second position (or vice versa) the two ends of the spring are urged closer together to increase the load on the spring, reaching their closest approach at a rotational position intermediate the first and second positions (and typically corresponding to half the full rotation). The spring is thus maximally loaded at the intermediate position. The result is that at all rotational positions from the first position to the intermediate position the closure member is biased towards the first position, and at all rotational positions of the closure member from the second position to the intermediate position the closure member is biased towards the second position.
Thus to rotate the closure member 105 from the first position to the second position, a torque is applied by the user against the bias urging the closure member to the first position until the intermediate position is reached whereupon the opposite bias carries the closure member to the second position. Similarly, to rotate the closure member 105 from the second position to the first position, a torque is applied by the user against the bias urging the closure member to the second position until the intermediate position is reached whereupon the opposite bias carries the closure member to the first position.
Accordingly, if torque is applied to move the closure member 105 to any position between the first and second positions, when that torque is released the closure member will automatically move to the first position and then remain in that position if the release position is between the first position and the intermediate position, but will automatically move to the second position and then remain in that position if the release position is between the second position and the intermediate position.
The spring 112 is permanently loaded to provide a bias at all rotational positions, and usefully this loading also helps to prevent rattling. Thus the spring provides a quiet, heat resistant,and reliable bistability mechanism.
The rotation axis R of the closure member 105 extends perpendicularly to the axis of the cavity 101. Thus, as the closure member is rotated about the rotation axis between the first position and the second position, a top surface of the closure member lying within its annular belt is exposed externally of the apparatus at the window 106 forming the mouth of the cavity. In this way, a portion of the surface of the closure member forming the externally exposed top surface in the first position contains the entry 108 to the bore 107. Indeed, as shown in Figs. 4A and 5A, the entry is preferably centred on the longitudinal axis of the device body 50. In contrast, as shown in Figs. 4B and 5B, the portion of the surface of the closure member forming the externally exposed top surface in the second position contains no part of the entry to the bore, but rather is smoothly and continuously curved in all directions. Thus the surfaces of the closure member externally exposed to the user of the apparatus in the first and second positions of the closure member are visually and functionally distinct.
In a similar fashion, a bottom surface of the closure member 105 is internally exposed to the cavity 101 at the underside of the closure member. Specifically, as shown in Figs. 5A and 7A, the portion of the surface of the closure member forming the internally exposed bottom surface in the first position contains the exit 109 from the bore 107, whereas, as shown in Figs. 5B and 7B, the portion of the surface of the closure member forming the internally exposed bottom surface in the second position contains no part of the exit. Instead, as shown for example in Figs. 7B and 8B, it can contain a heat shield which lines the surface of a conical depression 118 formed in the annular belt of the closure member. This heat shield, which may have a reflective surface, helps to reduce transfer of waste heat from the heating element 103 to the closure member after an activation of the apparatus. Thus movement between the first and second positions, exposes a pair of functionally distinct portions of the surface of the closure member to the cavity. Combined with the pair of portions externally exposed at the top surface, it is then possible to define four functionally distinct and contiguous sectors, or quadrants Q1-Q4, of the surface of the closure member, as shown in Figs. 11A and 11B which show respectively the plan views of the closure member Figs. 8D and 8E superimposed with dashed lines demarcating the following quadrants: Q1 = bore entry, Q2 = cover, Q3 = bore exit and Q4 = heat shield.
As previously discussed, the closure member 105 is rotatable back and forth by a predetermined angle of 90°, but it does not rotate beyond that. As a result, the two top quadrants are selectively exposed through the window 106 by rotating the closure member, but the two bottom quadrants remain concealed. Thus the heat shield formed at the conical depression 118 can be kept clean, and degradation of heat shield performance as a result of exposure/handling can be prevented.
As discussed above, the portion of the surface of the closure member 105 forming the externally exposed top surface in the second position is smoothly and continuously curved in all directions. It therefore contains no part of the entry 108 to the bore 107, but also it contains no part of the exit 109 from the bore 107. That is, the entry and the exit are both completely covered by the housing 100 when the closure member is in the second position. This is both visually and tactilely pleasing, and functions to prevent foreign objects from entering the bore.
Enough of the circumference of the closure member 105 is exposed through the window 106 in each of the first and second positions to allow a user to easily rotate the closure member from that position to at least the intermediate position, whereupon the bistability mechanism flips the closure member automatically to the other of the first and second positions.
The closure member 105 is formed of a material having a thermal conductivity of at least 100 Wm^-1K^-1, and preferably at least 200 Wm^-1K^-1. For example, the closure member may be formed of aluminium alloy, such as Al 6063 which has a thermal conductivity of about 210 Wm^-1K^-1. The thermal conductivity may be measured according to ISO 8302.
The closure member 105 is located above the cavity 101 and the heating element 103 at the mouth of the cavity. In this position it absorbs waste heat leaking from the cavity and not contributing to aerosol generation. Typically, the chassis 110 which defines the cavity 101 is largely or entirely metal-free and configured to provide heat insulation so that consumable heating is efficiently performed. Surprisingly, despite the relatively high thermal conductivity of the closure member 105 and its position above the cavity 101, it has been found not to reduce significantly the heating efficiency of the consumable. Moreover, and advantageously, the thermally conductive closure member 105 has been found to cool the generated aerosol and reduce temperature variation within it. Effectively, the thermal conductivity of the closure member 105, combined with its heat capacity, allows it to act as an effective heatsink "damper", producing a consistent user thermal experience over successive apparatus activations. Also, after an activation, the relatively high thermal conductivity rapidly reduces the surface temperature of the closure member, allowing the apparatus to be safely pocketed by the user.
As shown in Figs. 8A, 8B, 8C and 8D the closure member 105 has a pair of axle projections 120 on opposite sides of the closure member centred on the rotation axis R. These projections are received in respective holes 121 (see Figs. 10A to 10D) provided by walls 122 of the chassis 110, to provide a secure mounting structure in which the axle projections and holes form a pair of journal bearings allowing the closure member to rotate between the first and second positions.
The walls 122 are resiliently deformable, and each wall has a ramp surface 123 provided at its top edge. These properties allow the closure member 105 and the chassis 110 to be joined together via a quick and secure snap fit assembly operation. Fig. 12A shows perspective views of the first side of the chassis and the first side of the closure member as the closure member is offered for assembly into the chassis; Fig. 12B shows a longitudinal cross-section of the chassis and the closure member as the closure member is offered for assembly into the chassis; Fig. 12C is a close up of the part of Fig. 12B enclosed by a dashed rectangle; and Fig. 12D shows the longitudinal cross-section of Fig. 12B after assembly of the chassis and the closure member.
As shown in Figs. 12A and 12B, as the closure member 105 is lowered into the chassis 110, the axle projections 120 line up with the ramp surfaces 123 formed at the top (leading) edges of the walls 122. As best shown in Fig. 12C, the ramp surfaces are angled into the centre of the cavity so that, when the axle projections push down on them, they are forced apart, translating the downwards motion of the closure member into a flexing apart of the walls 122. Leaving the ramp surfaces behind them, the axle projections then continue downwards, sliding and pressing against the walls 122, until they arrive at the holes 121, whereupon the walls 122 snap back to their unflexed shape, with the axle projections 120 received in the holes (Figs. 6A and 12D). The closure member 105 is thus securely and rotatably retained in the chassis 110, with the walls 122 limiting any sideways translational motion of the closure member in the direction of the rotation axis R.

Claims

An aerosol generating apparatus, comprising:
a cavity (101) arranged within the apparatus for receiving a consumable aligned along an axis of the cavity,

an aerosol generating unit within the cavity configured to generate an aerosol from the consumable when axially received in the cavity, and

a rotatable closure member (105) arranged at a mouth (106) of the cavity to control access of the consumable to the cavity;

wherein the closure member:
has a bore (107) extending from an entry (108) at one side of the closure member to an exit (109) at an opposite side of the closure member, and

is rotatable about a rotation axis (R) between a first position in which the bore is aligned with the axis of the cavity such that a consumable inserted through the bore is further insertable into the cavity for axial reception therein, and a second position in which the bore is misaligned with the axis of the cavity such that the closure member blocks the mouth of the cavity and prevents reception of a consumable therein.
The aerosol generating apparatus according to claim 1, wherein the closure member (105) is substantially axisymmetric about the rotation axis (R), a portion of the surface of the closure member extending as an annular belt circumferentially around the closure member, with to either side of the annular belt the closure member having side surfaces centred on and substantially perpendicular to the rotation axis, wherein the annular belt contains the entry (108) to the bore (107), and the surface of the closure member in the annular belt curves convexly in both the circumferential and polar directions of the closure member.
The aerosol generating apparatus according to claim 2 further comprising a housing (100), the cavity (101) and the closure member (105) being provided inside the housing and the mouth of the cavity being formed by a window (106) in the housing, wherein:
in the first position, the entry (108) to the bore (107) is located within the window and, in the second position, either or both of the entry to and the exit (109) from the bore is/are at least partially covered by the housing, and

as the closure member is rotated between the first and second positions, progressively different parts of the annular belt are exposed externally through the window, while the side surfaces of the closure member remain completely covered by the housing.
The aerosol generating apparatus according to any one of the previous claims, wherein the perimeter of the entry (108) to the bore (107) is chamfered or rounded.
The aerosol generating apparatus according to any one of the previous claims further comprising a bistability mechanism which is configured to operate on the closure member (105) such that at all rotational positions of the closure member from the first position to a position intermediate the first and second positions the closure member is biased towards the first position, and at all rotational positions of the closure member from the second position to the intermediate position the closure member is biased towards the second position;
whereby, to rotate the closure member from a starting one of the first and second positions to a destination one of the other of the first and second positions, a torque is applied against the respective bias urging the closure member to the start position until the intermediate position is reached whereupon the opposite bias carries the closure member to the destination position.
The aerosol generating apparatus according to claim 5, wherein the bistability mechanism is a spring.
The aerosol generating apparatus according to claim 5 or 6, as dependent on claim 2, wherein the bistability mechanism is mounted to one of the side surfaces.
The aerosol generating apparatus according to any one of claims 5 to 7 further comprising a stop mechanism which limits rotational movement of the closure member to rotation between the first and second positions.
The aerosol generating apparatus according to any one of the previous claims, wherein:
the rotation axis (R) extends perpendicularly to the axis of the cavity (101), and the closure member (105) is configured to be rotated by a predetermined angle about the rotation axis to rotate between the first position and the second position, and

a top surface of the closure member is exposed externally of the apparatus at the mouth (106) of the cavity;

wherein the portion of the surface of the closure member forming the externally exposed top surface in the first position contains the entry (108) to the bore (107), and the portion of the surface of the closure member forming the externally exposed top surface in the second position contains no part of the entry to the bore.
The aerosol generating apparatus according to claim 9, wherein the predetermined angle is greater than 45° and/or up to 90°.
The aerosol generating apparatus according to claim 9 or 10, wherein the portion of the surface of the closure member forming the externally exposed top surface in the second position is smoothly and continuously curved in all directions.
The aerosol generating apparatus according to any one of claims 9 to 11, wherein a bottom surface of the closure member (105) is internally exposed to the cavity (101) at the underside of the closure member;
wherein the portion of the surface of the closure member forming the internally exposed bottom surface in the first position contains the exit (109) from the bore (107), and the portion of the surface of the closure member forming the internally exposed bottom surface in the second position contains no part of the exit from the bore.
The aerosol generating apparatus according to any one of the previous claims further comprising a housing (100), the cavity (101) and the closure member (105) being provided inside the housing and the mouth of the cavity being formed by a window (106) in the housing;
wherein the entry (108) and the exit (109) are both completely covered by the housing (100) when the closure member is in the second position.
The aerosol generating apparatus according to any one of the previous claims, wherein the aerosol generating unit is a heating system (103) and the closure member (105) is formed of a material having a thermal conductivity of at least 100 Wm^-1K^-1.
The aerosol generating apparatus according to claim 14, further comprising a chassis (110) that defines the cavity (101) and that retains the closure member (105) at a predetermined location in the apparatus such that the closure member is positioned at the mouth (106) of the cavity (101) with the closure member rotatable between the first position and the second position;
wherein the thermal conductivity of the material forming the closure member is at least 100 times higher than the thermal conductivity of the material forming the chassis.
The aerosol generating apparatus according to any one of the previous claims further comprising a chassis (110) that retains the closure member (105) at a predetermined location in the apparatus such that the closure member is positioned at the mouth (106) of the cavity with the closure member rotatable between the first position and the second position;
wherein the closure member and the chassis are configured such that, to assemble the apparatus, the closure member is slid into the chassis to arrive at the predetermined location, the closure member and the chassis cooperating to produce a snap fit on arrival of the closure member that retains the closure member at the predetermined location.
The aerosol generating apparatus according to claim 16, wherein the closure member (105) has a pair of axle projections (120) on opposite sides of the closure member and centred on the rotation axis (R), the axle projections being received in respective holes (121) provided by the chassis (110) on opposite sides of the closure member to form a pair of journal bearings such that the closure member is rotatable between the first position and the second position.
The aerosol generating apparatus according to claim 17, wherein the holes (121) are formed in respective walls (122) of the chassis (110), the walls being resiliently flexible to provide the snap fit on arrival of the axle projections in the holes when the closure member (105) is slid into the chassis (110) on assembly.
The aerosol generating apparatus according to claim 18, wherein each wall (122) has an angled ramp surface (123) at a leading edge of the wall which makes first contact with the respective axle projection (120) as the closure member (105) is slid into the chassis (110) on assembly, wherein the axle projections press against the ramp surfaces as the closure member is further slid into the chassis to gradually flex the walls apart.
The aerosol generating apparatus according to any one of claims 17 to 19 as dependent on claim 2, wherein each axle projection (120) is provided by a respective one of the side surfaces of the closure member (105).