An aerosol generating device and a method for operating an aerosol generating device

Abstract

An aerosol generating device (10) for generating an inhalable aerosol comprises: a casing (13) enclosing an aerosol generation unit (11); and a vibration generating unit (34) for generating a mechanical vibration (64) corresponding to a sound signal for audio output. The vibration generating unit (34) is configured to vibrate at least part of the casing (13) to amplify the mechanical vibration and thereby emit an audible sound (68) corresponding to the sound signal. A method for operating the aerosol generating device (10) to emit an audible sound (68) is also described.

Description

[0001] AN AEROSOL GENERATING DEVICE AND A METHOD FOR OPERATING AN AEROSOL GENERATING DEVICE

[0002] Technical Field

[0003] The present disclosure relates to an aerosol generating device, and in particular to an aerosol generating device that is configured to atomise or aerosolise an aerosol generating material to generate an aerosol for inhalation by a user. The present disclosure is particularly applicable to a portable (hand-held) aerosol generating device. The present disclosure also relates to a method for operating an aerosol generating device.

[0004] Technical Background

[0005] Devices which heat, rather than bum, an aerosol generating material to produce an aerosol for inhalation have become popular with consumers in recent years. A commonly available reduced-risk or modified-risk device is the heated material aerosol generating device, or so-called heat-not-bum device. Devices of this type generate an aerosol or vapour by heating an aerosol generating material, such as a non-liquid (e.g., solid) aerosol generating material, to a temperature typically in the range 150°C to 300°C. This temperature range is quite low compared to a conventional combustible cigarette. Heating the aerosol generating material to a temperature within this range, without burning or combusting the aerosol generating material, generates a vapour which typically cools and condenses to form an aerosol for inhalation by a user of the device. An aerosol may also be produced without heating (e.g., by using ultrasonic vibration or a chemical reaction), particularly if the device uses a liquid aerosol generating material.

[0006] An aerosol generating device is typically equipped with a user interface, which may be configured to provide information to a user, such as visual, auditory or haptic feedback. For example, an aerosol generating device may provide a notification or alert to a user by means of a light, a screen, a sound or a vibration. In the case of audible feedback, a speaker is typically located on the printed circuit board assembly (PCBA) or elsewhere in the aerosol generating device to generate the sound, but this approach can result in

[0007] P51788WO-6672 the generation of sounds which are subject to attenuation and / or distortion and can result in the occurrence of undesirable erratic sounds. There is, therefore, a need for an aerosol generating device which mitigates these drawbacks.

[0008] Summary of the Disclosure

[0009] According to a first aspect of the present disclosure, there is provided an aerosol generating device comprising: a casing enclosing an aerosol generation unit; and a vibration generating unit for generating a mechanical vibration corresponding to a sound signal for audio output; wherein the vibration generating unit is configured to vibrate at least part of the casing to amplify the mechanical vibration and thereby emit an audible sound corresponding to the sound signal.

[0010] According to a second aspect of the present disclosure, there is provided a method for operating an aerosol generating device to emit an audible sound, the aerosol generating device comprising: a casing enclosing an aerosol generation unit; and a vibration generating unit; wherein the method comprises: generating, by the vibration generating unit, a mechanical vibration corresponding to a sound signal for audio output; and vibrating, by the vibration generating unit, at least part of the casing to amplify the mechanical vibration and thereby emit an audible sound corresponding to the sound signal.

[0011] The aerosol generating device is configured to generate an inhalable aerosol, and in particular to atomise or aerosolise an aerosol generating material to generate an aerosol for inhalation by a user. The aerosol generating material may be provided as an aerosol generating article. In some examples, the aerosol generating device may be configured to heat an aerosol generating material without burning or combusting the aerosol generating material, to volatise at least one component of the aerosol generating

[0012] P51788WO-6672 material and thereby generate a heated vapour which may cool and condense to form an aerosol for inhalation by a user of the aerosol generating device. The aerosol generating device is typically a hand-held, portable, device which may be self- contained and low temperature.

[0013] In general terms, a vapour is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapour can be condensed to a liquid by increasing its pressure without reducing the temperature, whereas an aerosol is a suspension of fine solid particles or liquid droplets, in air or another gas. It should, however, be noted that the terms ‘aerosol’ and ‘vapour’ may be used interchangeably in this specification, particularly with regard to the form of the inhalable medium that is generated for inhalation by a user.

[0014] The at least part of the casing that is caused to vibrate by the vibration generating unit functions as a sound diaphragm which amplifies the mechanical vibration and emits the audible sound that corresponds to the sound signal. This solution allows the aerosol generating device to achieve clear and high-quality sound reproduction whilst mitigating sound attenuation, distortion and the occurrence of undesirable erratic sounds, without prejudicing a degree of freedom in designing the whole device.

[0015] Optional features will now be set out. These are applicable singly or in any combination with any aspect of the present disclosure.

[0016] The vibration generating unit may comprise a sound signal generator for generating an electric signal corresponding to the sound signal. The vibration generating unit may comprise an electroacoustic transducer for generating the mechanical vibration based on the electric signal generated by the sound signal generator. This arrangement allows for effective and convenient implementation of the vibration generating unit for converting the electric signal into the mechanical vibration.

[0017] The vibration generating unit may comprise an electric amplifier for amplifying the electric signal generated by the sound signal generator. The electroacoustic transducer

[0018] P51788WO-6672 may be arranged to convert the amplified electric signal into the mechanical vibration. This arrangement allows for amplification of the electric signal for the audio output, and thus suitable alignment of the electric signal with a power level required for the electroacoustic transducer.

[0019] The vibration generating unit may be configured to vibrate at least part of the casing to amplify the mechanical vibration and thereby emit an audible sound having a frequency from about 20 Hz to about 20 kHz in air. Thus, the sound diaphragm provided by the at least part of the casing is configured to emit an audible sound across the entire range of the audible spectrum. The sound diaphragm is, therefore, capable of generating a wide range of different audio outputs and / or auditory feedback. “Auditory feedback” as described herein means feedback provided in the form of a sound that is within the usual range of the audible spectrum as defined above.

[0020] The electroacoustic transducer may comprise a magnet affixed to the at least part of the casing. The electroacoustic transducer may comprise a coil for generating an electromagnetic field based on the generated electric signal to cause the magnet to vibrate. This arrangement provides an effective and convenient way of implementing the electroacoustic transducer causing the mechanical vibration.

[0021] The electroacoustic transducer may comprise a vibration motor. The electroacoustic transducer may comprise an Eccentric Rotating Mass (ERM) motor or a Linear Resonant Actuator (LRA) or a piezoelectric actuator. This arrangement provides another effective and convenient way of implementing the electroacoustic transducer causing the mechanical vibration.

[0022] The aerosol generating device may include a printed circuit board assembly (PCBA) onto which an electronic component (e.g., a coil) for controlling the electroacoustic transducer may be mounted. The electroacoustic transducer may be mechanically isolated from the printed circuit board assembly (PCBA) and more particularly from the electronic component, i.e., the electroacoustic transducer may not be mechanically coupled with the printed circuit board assembly (PCBA). This arrangement prevents

[0023] P51788WO-6672 the vibration caused by the electroacoustic transducer from having an adverse effect on other components of the aerosol generating device, especially on sensitive electronic components on the PCBA.

[0024] The at least part of the casing that may act as the sound diaphragm may form at least part of an external surface of the aerosol generating device. This arrangement prevents the audible sound emitted by the sound diaphragm from being attenuated by any other part of the device.

[0025] The at least part of the casing that may act as the sound diaphragm may form part of an internal surface of the aerosol generating device which is covered by an external surface of the aerosol generating device. This arrangement prevents the sound diaphragm from being inadvertently touched by a user, thus preventing the audible sound emitted by the sound diaphragm from being attenuated or distorted in any way.

[0026] The sound signal may be generated from a recording of a sound, which may, for example, be stored in a memory accessible to a controller of the aerosol generating device as a sound file, such as an MP3, AAC, WMA, or similar file. The sound may be a recording of a crackling sound, so as to be reminiscent of combustion of a conventional combustible cigarette. This may enhance the user experience because aerosol generating devices of the heat-not-bum variety, which heat, rather than bum, a non-liquid (e.g., solid) aerosol generating substrate, are typically substantially silent during operation.

[0027] The aerosol generating device may further comprise a puff detector for detecting inhalation by a user of aerosol generated by the aerosol generating unit. The term “puff detector” refers to a sensor, such as a pressure sensor or microphone, operable to detect the occurrence of a user inhalation. A puff detector may additionally be operable to detect parameters of the user inhalation, such as flow rate. The puff detector may be operable to detect a start of the user inhalation and an end of the user inhalation, the start and end together defining a puff duration. The controller may be operable to control the vibration generating unit to generate the audible sound for substantially the

[0028] P51788WO-6672 puff duration. The vibration generating unit may be arranged to generate the mechanical vibration corresponding to the sound signal, e.g., based on the recording of a crackling sound, when a user inhalation is detected by the puff detector. Accordingly, there is an improvement in the user experience, and, thus, an improvement in the level of user satisfaction, during user inhalation because the sound, e.g., crackling sound, emitted by the sound diaphragm (as formed by said at least part of the casing) is directly associated with, and perceived by the user to be caused by, the user inhalation. The provision of auditory feedback (i.e., an audible sound) in response to a user inhalation therefore has particular utility in aerosol generating devices of the heat-not-bum variety.

[0029] The vibration generating unit may be arranged to adjust a magnitude of the mechanical vibration based on an instantaneous flow rate of the user inhalation. This arrangement allows for dynamic alteration of the audible sound emitted by the at least part of the casing that may act as the sound diaphragm, according to the user’s inhalation volume, thus further enhancing the user experience. In this way, one or more characteristics (e.g., sound level) of the audible sound may be caused to vary as the depth of the user’s inhalation varies, which may further improve the user’s perception that the aerosol generating device is responsive to their inhalation. The vibration generating unit may be arranged to adjust a magnitude of the mechanical vibration so that the sound level may increase as the measured instantaneous flow rate increases, and may decrease as the measured instantaneous flow rate decreases. In this way the user may have the perception that the emitted audible sound is proportional to the intensity of their inhalation.

[0030] The aerosol generating device may comprise a heating chamber configured to receive a consumable comprising a non-liquid aerosol generating substrate, and a heating assembly configured to cause heating of the aerosol generating substrate during use. The heating chamber may be substantially cup shaped, and may have an open first end operable to receive a non-liquid (e.g., solid) consumable. For example, the heating chamber may comprise a substantially cylindrical side wall that is open at a first end, so defining the open first end, and closed at a second end, defining a base to the heating

[0031] P51788WO-6672 chamber. The heating arrangement may be external to the heating chamber, and may be wrapped around the heating chamber.

[0032] The non-liquid aerosol generating substrate may comprise any type of solid or semisolid material. Example types of aerosol generating solids include powder, granules, pellets, shreds, strands, particles, gel, strips, loose leaves, cut filler, porous material, foam material or sheets. The non-liquid aerosol generating substrate may comprise plant derived material and in particular, may comprise tobacco. It may advantageously comprise reconstituted tobacco, for example including tobacco and any one or more of cellulose fibres, tobacco stalk fibres and inorganic fillers such as CaCCh. The reconstituted tobacco may comprise tobacco sheets of any kind (paper-like sheets, cast tobacco sheets, corrugated sheets, etc.) in full sheets being crimped, folded and / or rolled or sheet fragments, and in an orientated gathered form (e.g., parallel arrangement or weaved pattern of substantially identical sheet fragments) or in randomly arranged form (e.g., sheet fragments of various sizes and shapes in bulk mixed form as tobacco cut filler).

[0033] Consequently, the aerosol generating device may be referred to as a “heated tobacco device”, a “heat-not-bum tobacco device”, a “device for vaporising tobacco products”, a “T-vapour” device and the like, with this being interpreted as a device suitable for achieving these effects. The features disclosed herein are equally applicable to devices which are designed to vaporise any aerosol generating material, including a liquid material or substrate.

[0034] The consumable may be formed substantially in the shape of a stick, and may broadly resemble a cigarette, having a tubular region with an aerosol generating material or substrate arranged in a suitable manner. The consumable may include a filter segment, for example comprising cellulose acetate fibres, at a proximal end of the aerosol generating article. The filter segment may constitute a mouthpiece filter and may be in coaxial alignment with the aerosol generating material. One or more vapour collection regions, cooling regions, and other structures may also be included in some designs. For example, the consumable may include at least one tubular segment upstream of the

[0035] P51788WO-6672 filter segment. The tubular segment may act as a vapour cooling region. The vapour cooling region may advantageously allow the heated vapour generated by heating the aerosol generating substrate to cool and condense to form an aerosol with suitable characteristics for inhalation by a user, for example through the filter segment.

[0036] The non-liquid aerosol generating substrate may comprise an aerosol-former. Examples of aerosol-formers include polyhydric alcohols and mixtures thereof such as glycerine or propylene glycol. In other possible examples, the aerosol-former may include other alcohols, such as ethanol, 1,3-propanediol, or may include water. Typically, the nonliquid aerosol generating substrate may comprise an aerosol-former content of between approximately 5% and approximately 50% on a dry weight basis of the non-liquid aerosol generating substrate. In some embodiments, the non-liquid aerosol generating substrate may comprise an aerosol-former content of between approximately 10% and approximately 20% on a dry weight basis of the non-liquid aerosol generating substrate, and possibly approximately 15% on a dry weight basis of the non-liquid aerosol generating substrate.

[0037] Upon being heated, the non-liquid aerosol generating substrate may release volatile compounds. The volatile compounds may include nicotine or flavour compounds such as tobacco flavouring.

[0038] Brief Description of the Drawings

[0039] Figure 1 is a diagrammatic cross-sectional view of an aerosol generating system comprising an aerosol generating device and a consumable positioned in a heating chamber of the aerosol generating device;

[0040] Figure 2 is a schematic illustration of a sound generating system including a vibration generating unit suitable for use in an aerosol generating device of the type shown in Figure 1;

[0041] Figure 3 illustrates a relationship between flow rate and time for a typical user inhalation;

[0042] Figure 4 illustrates a relationship between an audible sound and instantaneous flow rate during a user inhalation;

[0043] P51788WO-6672 Figure 5 is a diagrammatic illustration of an example of an electroacoustic transducer for use in the vibration generating unit of Figure 2; and

[0044] Figure 6 is a schematic illustration of a method for operating an aerosol generating device to emit an audible sound.

[0045] Detailed Description of Embodiments

[0046] Embodiments of the present disclosure will now be described by way of example only and with reference to the accompanying drawings.

[0047] Referring initially to Figure 1, there is shown diagrammatically an example of an aerosol generating system 1. The aerosol generating system 1 comprises an aerosol generating device 10 and a consumable 100, also referred to herein as an aerosol generating article, for use with the device 10. The aerosol generating device 10 comprises a main body 12 in the form of a casing 13 which encloses various components of the aerosol generating device 10 including an aerosol generating unit 11. The casing 13 has an outer surface 13a, which defines the external shape of the aerosol generating device 10. The casing 13 may have any shape that is sized to enclose the components described in the various examples set out herein, and to be comfortably held by a user unaided, in a single hand.

[0048] A first end 14 of the aerosol generating device 10, shown towards the bottom of Figure 1, is described for convenience as a distal, bottom, base or lower end of the aerosol generating device 10. A second end 16 of the aerosol generating device 10, shown towards the top of Figure 1, is described as a proximal, top or upper end of the aerosol generating device 10. During use, the user typically orients the aerosol generating device 10 with the first end 14 downwards and / or in a distal position with respect to the user’s mouth and the second end 16 upwards and / or in a proximal position with respect to the user’s mouth.

[0049] The aerosol generating device 10, and more particularly the aerosol generating unit 11, comprises a heating chamber 18 positioned in the main body 12. The heating chamber 18 defines an interior volume in the form of a cavity 20 having, in this example, a

[0050] P51788WO-6672 substantially cylindrical cross-section. The cavity 20 of the heating chamber 18 is open towards the second end 16 of the aerosol generating device 10. The heating chamber 18 has a longitudinal axis defining a longitudinal direction and is formed of any suitable heat-resistant material, such as a heat resistant plastics material, e.g. polyether ether ketone (PEEK), or a metal material, such as stainless steel.

[0051] A heating arrangement 22, which also forms part of the aerosol generating unit 11, is located in proximity to the heating chamber 18 and is operable to provide heat to the heating chamber 18. The aerosol generating device 10 further comprises apower source 26, for example one or more batteries which may be rechargeable, and a controller 24. The controller 24 may comprise one or more integrated circuits and other electrical components, such as a microcontroller unit (MCU) and / or microprocessor unit (MPU). The controller 24 may comprise a printed circuit board assembly (PCBA) 24a.

[0052] The controller 24 couples the power source 26 to the heating arrangement 22. The controller 24 may also be connected to a user interface 23 comprising inputs such as a power button for receiving commands from a user and / or outputs such as indicator lights or a display screen for providing information to the user. The controller 24 may also be connected to an antenna 25 for wireless communication with a remote device such as the user’s smartphone, which can be used for input and output, as well as for relaying data between the aerosol generating device 10 and external entities such as its manufacturer.

[0053] The heating chamber 18, and specifically the cavity 20, is arranged to receive a correspondingly shaped generally cylindrical or rod-shaped aerosol generating article 100, also termed herein a consumable. Typically, the aerosol generating article 100 comprises a pre-packaged solid (i.e., non-liquid) aerosol generating substrate 102. The aerosol generating article 100 is a disposable and replaceable article, which may, for example, contain tobacco as the solid aerosol generating substrate 102. The aerosol generating article 100 has a proximal end 104 (or mouth end) and a distal end 106. The distal end 106 is inserted into the heating chamber 18 of the aerosol generating device 10 so that at least the aerosol generating substrate 102 is contained

[0054] P51788WO-6672 within the heating chamber 18. The aerosol generating article 100 further comprises a mouthpiece segment 108 positioned downstream of the aerosol generating substrate 102. At least part of the mouthpiece segment 108 projects from the heating chamber 18 so that the proximal end 104 of the aerosol generating article 100 is accessible to be taken into the mouth of a user. When the aerosol generating device 10 applies heat to the aerosol generating article 100, heated vapour is emitted from the aerosol generating substrate 102. As inhalation by the user draws air towards the proximal end 104 of the aerosol generating article 100, the vapour cools and condenses as it passes through the mouthpiece segment 108 to form an aerosol with characteristics suitable for inhalation. The mouthpiece segment 108 may further comprise a filter (not shown) to remove particles or drops above a certain size from the airstream.

[0055] The aerosol generating substrate 102 and the mouthpiece segment 108 are arranged in coaxial alignment inside a wrapper 110 (e.g., a paper wrapper) to hold the components in position to form the rod-shaped aerosol generating article 100. The wrapper 110 typically does not cover the ends 104, 106 of the aerosol generating article 100 in order that air can flow through the aerosol generating article 100 from the distal end 106 to the proximal end 104.

[0056] In the illustrated embodiments, the heating chamber 18 comprises an open first end 28 and a closed base 30 at a second end. That is, the heating chamber 18 is cup shaped. This can ensure that air drawn from the open end 28 is guided around the consumable towards the base 30, at which point the air is drawn through the aerosol generating substrate 102.

[0057] The aerosol generating device 10 may optionally include a closure (not visible in Figure 1), such as a sliding cover, movable between a closed position in which it covers the open first end 28 of the heating chamber 18 and an open position in which it exposes the open first end 28 of the heating chamber 18 to provide access to the heating chamber 18. The closure may be biased towards the closed position if required.

[0058] P51788WO-6672 In accordance with the present disclosure, an aerosol generating device 10 further comprises a sound generating system 32 that is operable to emit an audible sound. The sound generating system 32 is operable to emit an audible sound within the usual range of human hearing (which is typically 20 Hz to 20 kHz in air). Since the audible sound is intended to be user-discernible, the sound generating system 32 may be considered part of the user interface 23 of the aerosol generating device 10.

[0059] The exemplary aerosol generating device 10 shown in Figure 1 additionally comprises a puff detector 36. The puff detector 36 is a sensor, such as a pressure sensor or microphone, that is operable to detect a user’s inhalation of aerosol generated by the aerosol generating device 10. In some embodiments, the controller 24 of the aerosol generating device 10 is operable to control the sound generating system 32 to generate the audible sound when a user inhalation is detected.

[0060] When consumed, a conventional combustible cigarette typically generates a number of outputs due to combustion, including heat, sound, light and inhalable vapour. Some of these combustion outputs may vary during a smoking session, and thus can be interpreted by a user smoking the cigarette as “feedback” on the progress of the smoking session. Reduced-risk aerosol generating devices typically also generate an inhalable vapour as an output of operation. However, other outputs resulting from the operation of such devices may vary from those produced by a combustible cigarette, and thus such devices may provide a different experience to a user as compared with the experience provided by a conventional combustible cigarette. This is particularly the case for heat-not-bum aerosol generating devices of the type shown in Figure 1, since such devices are often silent during operation. Providing auditory feedback in the form of an audible sound when a user inhalation is detected thus ensures that the outputs of the aerosol generating device change in a noticeable way when a user inhales. This increases the ability of the user to perceive the impact of their inhalation on the aerosol generating device, which can enhance the user experience and / or improve the user’s perception of having control over the heating experience.

[0061] P51788WO-6672 Figure 2 shows the exemplary sound generating system 32 of Figure 1 in more detail. In the particular example shown, the sound generating system 32 includes a vibration generating unit 34 for generating a mechanical vibration 64 corresponding to a sound signal for audio output. The vibration generating unit 34 is configured to vibrate at least part of the casing 13 to amplify the mechanical vibration 64 and thereby emit an audible sound 68 corresponding to the sound signal. The at least part of the casing 13 that is caused to vibrate by the vibration generating unit 34 thus functions as a sound diaphragm.

[0062] An MP3 module 52 (or other type of module / system operable to encode sound files) is provided in communication with both the controller 24 and the vibration generating unit 34. The audible sound 68 emitted by the sound generating system 32 is thus generated from an MP3 file encoded in a memory of the MP3 module 52. The file may be a recording of a sound that is reminiscent of crackling or burning. It will be understood that MP3 is only one of many options for encoding audio information, and that other file types than MP3 could be used if preferred. Similarly, it will be understood that other recorded or artificially generated sound files could be used if preferred, such as music.

[0063] In the exemplary device shown in Figures 1 and 2, the controller 24 is operable to control the sound generating system 32 to generate the audible sound 68 when a user inhalation is detected. The audible sound 68 is generated continuously throughout the course of the user inhalation, and ceases when it is detected by the puff detector 36 that the user inhalation has ended. The audible sound 68 is thus provided throughout the duration of the user inhalation (also termed herein “a puff’), and serves as a clear indication to the user that their inhalation is having an effect on the operation of the aerosol generating device 10. When a further user inhalation is detected, the controller 24 is again operable to control the sound generating system 32 to generate the audible sound 68. An audible sound 68 is thus provided whenever a user inhalation is detected (i.e., for each user inhalation that occurs during a smoking session). A user is thus provided with a clear indication that vapour production is occurring when they are inhaling, because auditory feedback (in the form of the audible sound 68) is provided

[0064] P51788WO-6672 which indicates that the aerosol generating device 10 is responsive to the user’s inhalations.

[0065] Figure 3 shows a schematic example of a typical puff, in which the flow rate 54 (in mL / s) through the aerosol generating device 10 varies over time (in seconds) between a start time ti and an end time t2. The start and end times together define a puff duration 56, during which the flow rate 54 typically rises from zero (or a negligible low threshold) at ti to a maximum Fmaxat an intermediate time before falling back to zero or negligible at t2. A typical puff duration 56 might be between 2-4 seconds, e.g. 3 or 3.5 seconds. At any arbitrary time txduring the puff duration 56, the puff detector 36 measures the instantaneous flow rate F(x), whilst a cumulative flow rate can be obtained by integrating the instantaneous flow rate signal, if required.

[0066] As illustrated schematically in Figure 4, the audible sound 68 that is provided by the aerosol generating device 10, and more specifically by the sound generating system 32, may vary throughout the puff duration 56. More specifically, the sound level (e.g., volume) of the audible sound 68 may be caused to vary during the puff duration 56 in response to the instantaneous flow rate F(x) as measured by the puff detector 36.

[0067] In the example shown in Figure 4, the controller 24 is operable to select a volume of the audible sound 68 in response to the measured instantaneous flow rate. The volume of the audible sound provided by the sound generating system 32 thus varies as a function of the measured instantaneous flow rate F(x). In the example shown in Figure 4, the volume of the audible sound 68 increases when the measured flow rate increases, decreases when the measured flow rate decreases, and is absent when there is no flow. In this way the user receives the impression that the aerosol generating device 10 is responding to the intensity of their inhalation.

[0068] The aerosol generating device 10 may alternatively, or additionally, respond to other control parameters than the instantaneous flow rate.

[0069] P51788WO-6672 Referring again to Figure 2 and also to Figure 6 which schematically illustrates a method for operating an aerosol generating device 10 to generate an audible sound 68, the vibration generating unit 34 includes a sound signal generator 38, an electric amplifier 40 and an electroacoustic transducer 42. The sound signal generator 38 is configured to generate an electric signal 60 corresponding to the sound signal. The sound signal may, for example, be generated from an MP3 file encoded in a memory of the MP3 module 52 as discussed above. The electric amplifier 40 is configured to amplify the electric signal 60 generated by the sound signal generator 38 to provide an amplified electric signal 62. The electroacoustic transducer 42 is configured to convert the amplified electric signal 62 into a mechanical vibration 64. As discussed above, the mechanical vibration 64 causes at least a part of the casing 13 of the aerosol generating device 10 to vibrate. Accordingly, the at least part of the casing 13 that is caused to vibrate acts as a sound diaphragm which amplifies the mechanical vibration (to generate an amplified mechanical vibration 66) and thereby emits an audible sound 68 corresponding to the sound signal. A clear and high-quality sound reproduction is thereby achieved whilst sound attenuation, distortion and the occurrence of undesirable erratic sounds are at least minimised, and possibly avoided.

[0070] Referring to Figure 5, in one example the electroacoustic transducer 42 includes a magnet 44 affixed to at least part of an inner surface of the casing 13 and a coil 46 mounted on the PCBA 24a. The coil 46 is configured to generate an electromagnetic field based on the generated sound signal, and more particularly based on the amplified electric signal 62, and the electromagnetic field is arranged to vibrate the magnet 44 as shown diagrammatically by the arrows in Figure 5, which in turn vibrates the at least part of the casing 13 to which the magnet 44 is affixed, to thereby amplify the mechanical vibration 64 and generate the audible sound 68.

[0071] In other examples, the electroacoustic transducer 42 may comprise an Eccentric Rotating Mass (ERM) motor, a Linear Resonant Actuator (LRA), a piezoelectric actuator, or similar. Such an arrangement allows for a low cost and simple construction of the aerosol generating device.

[0072] P51788WO-6672 In order to ensure that the mechanical vibration 64 generated by the electroacoustic transducer 42 does not have an adverse effect on other components of the aerosol generating device 10, and in particular sensitive electronic components that are typically mounted on the PCBA 24a, it may be desirable that the electroacoustic transducer 42 is mechanically isolated from (i.e., not mechanically coupled with) the PCBA 24a.

[0073] In some embodiments, the at least part of the casing 13 that is caused to vibrate by the electroacoustic transducer 42 to produce the audible sound 68 (i.e., the part of the casing 13 that acts as the sound diaphragm) can form part of an outer (or external) surface 13a of the aerosol generating device 10. In other embodiments, the at least part of the casing 13 that is caused to vibrate by the electroacoustic transducer 42 to produce the audible sound 68 (i.e., the part of the casing 13 that acts as the sound diaphragm) can form part of an internal surface of the aerosol generating device 10 that is covered by an outer (or external) surface 13a.

[0074] In some embodiments, the devices and methods described herein can combine a sensor (e.g., a puff detector 36) and an actuator (e.g., an electroacoustic transducer 42) to enhance the user experience of an aerosol generating device, such as a heat-not-bum (HnB) or heated tobacco system (HTS) device, by providing dynamic sound feedback tailored to the usage conditions. Unlike traditional HnB and HTS devices, which lack feedback during inhalation, this innovation aims to engage the user’s sense of sound, thereby enhancing the perception and user experience during each puff.

[0075] Although exemplary embodiments have been described in the preceding paragraphs, it should be understood that various modifications may be made to those embodiments without departing from the scope of the appended claims. Thus, the breadth and scope of the claims should not be limited to the above-described exemplary embodiments.

[0076] The heating arrangement 22 may comprise an electrical resistive heater or an induction heater. The induction heater may comprise an induction coil and a susceptor which may be part of the aerosol generating device 10 or the aerosol generating article 100. In other

[0077] P51788WO-6672 embodiments, the heating arrangement 22 may be replaced by an aerosol generation unit that generates an aerosol without heating (e.g., by using ultrasonic vibration or a chemical reaction). Any combination of the above-described features in all possible variations thereof is encompassed by the present disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

[0078] Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like, are to be construed in an inclusive as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.

[0079] P51788WO-6672

Claims

Claims1. An aerosol generating device (10) comprising: a casing (13) enclosing an aerosol generation unit (11); and a vibration generating unit (34) for generating a mechanical vibration (64) corresponding to a sound signal for audio output; wherein the vibration generating unit (34) is configured to vibrate at least part of the casing (13) to amplify the mechanical vibration and thereby emit an audible sound (68) corresponding to the sound signal.

2. An aerosol generating device according to claim 1, wherein the vibration generating unit (34) comprises: a sound signal generator (38) for generating an electric signal (60) corresponding to the sound signal; and an electroacoustic transducer (42) for generating the mechanical vibration (64) based on the electric signal (60) generated by the sound signal generator (38).

3. An aerosol generating device according to claim 2, wherein the vibration generating unit (34) further comprises an electric amplifier (40) for amplifying the electric signal (60) generated by the sound signal generator (38) and the electroacoustic transducer (42) is arranged to convert the amplified electric signal (62) into the mechanical vibration (64).

4. An aerosol generating device according to any preceding claim, wherein the vibration generating unit (34) is configured to vibrate at least part of the casing (13) to amplify the mechanical vibration (64) and thereby emit an audible sound (68) having a frequency from 20 Hz to 20 kHz.

5. An aerosol generating device according to any of claims 2 to 4, wherein the electroacoustic transducer (42) comprises: a magnet (44) affixed to said at least part of the casing (13); and a coil (46) for generating an electromagnetic field based on the generated electric signal (60) to cause the magnet (44) to vibrate.P51788WO-66726. An aerosol generating device according to any of claims 2 to 4, wherein the electroacoustic transducer (42) comprises a vibration motor.

7. An aerosol generating device according to claim 6, wherein the vibration motor comprises an Eccentric Rotating Mass (ERM) motor or a Linear Resonant Actuator (LRA) or a piezoelectric actuator.

8. An aerosol generating device according to any of claim 2 to 7, wherein the aerosol generating device (10) includes a printed circuit board assembly (PCBA) (24a) onto which an electronic component for controlling the electroacoustic transducer (42) is mounted and the electroacoustic transducer (42) is mechanically isolated from the printed circuit board assembly (PCBA) (24a).

9. An aerosol generating device according to any preceding claim, wherein said at least part of the casing (13) forms at least part of an external surface (13a) of the aerosol generating device (10).

10. An aerosol generating device according to any of claim 1 to 8, wherein said at least part of the casing (13) forms at least part of an internal surface of the aerosol generating device (10) which is covered by an external surface (13a) of the aerosol generating device (10).

11. An aerosol generating device according to any preceding claim, wherein the sound signal is generated from a recording of a sound, the sound preferably being a crackling sound.

12. An aerosol generating device according to any preceding claim, further comprising: a puff detector (36) for detecting inhalation by a user of aerosol generated by the aerosol generating unit (11);P51788WO-6672wherein the vibration generating unit (34) is arranged to generate the mechanical vibration (64) corresponding to the sound signal when a user inhalation is detected.

13. An aerosol generating device according to claim 12, wherein the vibration generating unit (34) is arranged to adjust a magnitude of the mechanical vibration (64) based on an instantaneous flow rate of the user inhalation.

14. A method for operating an aerosol generating device (10) to emit an audible sound (68), the aerosol generating device (10) comprising: a casing (13) enclosing an aerosol generation unit (11); and a vibration generating unit (34); wherein the method comprises: generating, by the vibration generating unit (34), a mechanical vibration (64) corresponding to a sound signal for audio output; and vibrating, by the vibration generating unit (34), at least part of the casing (13) to amplify the mechanical vibration and thereby emit an audible sound (68) corresponding to the sound signal.

15. A method according to claim 14, wherein the sound signal is generated from a recording of a sound, the sound preferably being a crackling sound.P51788WO-6672

Images