WO2016079533A1

WO2016079533A1 - Apparatus and methods for monitoring aerosol delivery

Info

Publication number: WO2016079533A1
Application number: PCT/GB2015/053541
Authority: WO
Inventors: Nicholas OAKES; Sandra Jane SLAYFORD; Carl Alexander VAS; Jeremy LIPSCOMBE
Original assignee: Nicoventures Holdings Limited
Priority date: 2014-11-20
Filing date: 2015-11-20
Publication date: 2016-05-26
Also published as: EP3221668A1; GB201420649D0

Abstract

An apparatus for measuring the flow of aerosol from an aerosol delivery device, such as an e-cigarette. The apparatus comprises a main body defining a measurement chamber in a flow path extending from an aerosol-input end of the apparatus to a mouthpiece end of the apparatus. When in use, aerosol drawn into the aerosol-input end of the apparatus from an aerosol delivery device flows along the flow path and through the measurement chamber and out through the mouthpiece end of the apparatus. The apparatus further comprises a sensor for measuring a drop in pressure along a part of the flow path within the measurement chamber to allow characteristics of aerosol flow along the flow path to be measured, (e.g. flow rate, puff volumes, etc.). Thus, a user may use the aerosol delivery device (i.e. puff aerosol generated by the aerosol delivery device) via the monitoring apparatus to allow characteristics relating to the delivery of aerosol to be monitored during use (e.g. flow rate, puff volumes and timings, etc.). The apparatus further comprises a diffusion element arranged between the aerosol-input end of the apparatus and the measurement chamber to diffuse the flow of aerosol entering the flow path from an aerosol delivery device before it reaches the measurement chamber. The diffusion element may, for example, comprise an extension tube providing an extended section of flow path between the aerosol-input end of the apparatus and the measurement chamber.

Description

APPARATUS AND METHODS FOR MONITORING AEROSOL DELIVERY Field

The present disclosure relates to apparatus and methods for monitoring one or more characteristics of aerosol delivery from an aerosol delivery device such as a nicotine delivery system (e.g. an e-cigarette).

Background

Figure 1 schematically represents a known device (smoking behaviour analyser) 1 for monitoring characteristics associated with smoking a smoking article, such as a cigarette. The smoking behaviour analyser 1 of Figure 1 is described in WO 2004/047570 [1] and similar devices are described in WO 2002/098245 [2]. Smoking behaviour analysers of the kind described in these documents and represented in Figure 1 allow the topography of a user's smoking profile to be established by measuring characteristics of a user's puffs on a cigarette, such as flow rate, duration and mainstream smoke density.

The device 1 comprises a housing 4, at one end of which is secured a hollow sleeve 5 and at the opposite end of which is secured a mouthpiece holder 6. In normal use a cigarette 7 is mounted in the sleeve 5 and a disposable mouthpiece 8 is attached to the mouthpiece holder 6. Thus the mouthpiece 8 is in fluid-flow communication with the cigarette 7 via the hollow interior of the housing 4 and the cigarette may be smoked from the mouthpiece with the associated mainstream smoke passing through the hollow interior of the housing 4.

The device 1 includes a fluid-flow pressure drop detector comprising an orifice plate 9 in the flow path of air drawn through the device and two openings 10, 11 in the housing on either side of the orifice plate 9. The openings 10, 1 1 are in fluid communication with respective pressure transducers 17, 18 in a data acquisition unit and transmission 14 of a data processing and display assembly 2 via tubing 3. The pressure transducers 17, 18 connected to the respective openings 10, 1 1 thus allow for measurements of pressure on either side of the orifice 9. From these pressure measurements, and taking account of the size of the orifice, flow rate information can be derived for air drawn through the orifice as a user puffs on the cigarette 7. Further characteristics relating to the user's puffs that may be of interest in a given scenario can be established from the flow rate measurements. For example, the flow rate measurement can be used to determine characteristics such as the total volume of air drawn during a puff (by integrating the flow rate over a puff) and characteristics associated with timings for the puffs (e.g. puff duration, interval between puffs, total number of puffs), and so on.

Also mounted within the housing 4 is a smoke density detector comprising a light emitter 12, in this instance a light emitting diode and, facing the light transmitter 12, a light receiver 13, in this instance a photodiode. The light emitter 12 and the light receiver 13 are electrically coupled to the data acquisition and transmission unit 14 via wiring 3'. The light emitter 12 and associated light receiver 13 allow a measurement of the density of smoke (concentration of particulate phase components) in the housing 4 based on a measure of the amount of scattering occurring between the light emitter 12 and the light receiver 13 (i.e. the optical density of the smoke). Smoke concentration values from measurements of light extinction obtained using the light emitter 12 and the light receiver 13 may be determined using a calibration curve derived from light extinction data for reference cigarettes with known smoke yields at certain concentrations.

The data processing and display assembly 2 is operable to establish pressure measurements using the pressure transducers located within the data acquisition and transmission unit 14 and connected to the openings 10, 1 1 on either side of the orifice 9. The data acquisition and transmission unit 14 also drives the light transmitter 12 and receives signalling from the light receiver 13 to allow for light extinction measurements. The data acquisition and transmission unit 14 transmits data derived from the pressure measurements and light receiver signals to a data processor 15, for example a suitably-programmed general-purpose computer, for further processing. Results derived from processing the measurements associated with the pressure transducers 17, 18 and the light receiver 13 which represent various characteristics associated with the smoking of the cigarette may be displayed on a display 16 associated with the processor 15.

Thus the data acquisition and transmission unit 14 is operable to establish a series of pressure and smoke density measurements as a cigarette is smoked, for example at a sampling rate of 25 measurements per second. These measurements are communicated to the data processor 15. The data processor 15 uses the flow-rate measurements to establish estimates of smoking behaviour characteristics, such as puff volumes, puff shapes and puff durations and intervals. The data processor 15 may further use light extinction

measurements obtained using the light transmitter 12 and light receiver 13 to establish measurements of smoke concentration during the smoking of the cigarette. The data processor 15 may then combine the smoke flow rate and smoke concentration to calculate puff-by-puff deliveries of smoke for the cigarette, total delivery of smoke for the cigarette, and so on.

The device 1 represented in Figure 1 has been found to perform very well and to provide valuable results when analysing users' smoking behaviour ("puffing topography"). Determining users' smoking behaviour with such devices can be important in various scenarios, for example to identify differences in smoke delivery for a user who is actually smoking a cigarette as compared to a cigarette smoked on a smoking machine in accordance with standard methods (such as set out by ISO 3308.2000). This kind of information can be used, for example, to establish more appropriate testing regimes for cigarettes by configuring smoking machines to operate in a manner which better reflects user smoking behaviour.

The use of aerosol delivery devices, such as electronic-cigarettes (e-cigarettes), is becoming more prevalent and there is a corresponding desire to monitor the use of such aerosol delivery devices in a manner similar to how the use of conventional cigarettes is monitored using devices of the kind represented in Figure 1. However, the inventors have recognised that devices of the kind represented in Figure 1 that work well for analysing the use of conventional cigarettes can suffer some drawbacks when for analysing the use of aerosol delivery devices, such as e-cigarettes, because of differences between conventional cigarette smoke and the aerosols generated by aerosol delivery devices.

There is therefore a need for improved apparatus and methods for monitoring one or more characteristics of aerosol delivery from an aerosol delivery device, such as a nicotine delivery system (e.g. e-cigarettes).

Summary

According to an aspect of certain embodiments, there is provided an apparatus for measuring the flow of aerosol from an aerosol delivery device; the apparatus comprising; a main body defining a measurement chamber in a flow path extending from an aerosol-input end of the apparatus to a mouthpiece of the apparatus such that aerosol drawn into the aerosol-input end of the apparatus from an aerosol delivery device flows along the flow path and through the measurement chamber and out through the mouthpiece of the apparatus; a sensor arrangement for measuring a drop in pressure along a part of the flow path within the measurement chamber; and a diffusion element arranged between the aerosol-input end of the apparatus and the measurement chamber to diffuse the flow of aerosol entering the flow path from an aerosol delivery device before it reaches the measurement chamber.

According to another aspect of certain embodiments, there is provided an apparatus for measuring the flow of aerosol from an aerosol delivery device; the apparatus comprising: a main body defining a measurement chamber in a flow path extending from an aerosol- input end of the apparatus to a mouthpiece-end of the apparatus such that aerosol drawn into the aerosol-input end of the apparatus from an aerosol delivery device flows along the flow path and through the measurement chamber and out through the mouthpiece-end of the apparatus and a sensor arrangement for measuring a drop in pressure along a part of the flow path within the measurement chamber; wherein the sensor arrangement comprises a first pressure sensor connected to a first passageway extending through the main body of the apparatus to a first opening at a first location along the flow path in the measurement chamber and a second pressure sensor connected to a second passageway extending through the main body of the apparatus to a second opening at a second location along the flow path in the measurement chamber, thereby allowing measurements of pressure in the measurement chamber in the vicinity of the first and second locations, the apparatus further comprising a handle for a user to hold the apparatus, wherein the handle is arranged to support the main body of the apparatus in an orientation in which the first and second openings are in an upper portion of the measurement chamber (i.e. offset from the lowest point in the measurement chamber) when the apparatus is being held by a user in normal use.

According to another aspect of certain embodiments, there is provided an apparatus for measuring the flow of aerosol from an aerosol delivery device; the apparatus comprising: a main body defining a measurement chamber in a flow path extending from an aerosol- input end of the apparatus to a mouthpiece-end of the apparatus such that aerosol drawn into the aerosol-input end of the apparatus from an aerosol delivery device flows along the flow path and through the measurement chamber and out through the mouthpiece-end of the apparatus, and a sensor arrangement for measuring pressure on either side of a flow restrictor plate in the measurement chamber, wherein the flow restrictor plate is removable from the apparatus for cleaning.

Various other aspects and features of certain embodiment of the invention are defined in the appended claims. It will be appreciated that features and aspects described herein in relation to certain embodiments are equally applicable to, and may be combined with, features and aspects of other embodiments as appropriate, and not just in the specific combinations discussed herein.

Brief Description of the Drawings

Various embodiments will now be described in detail by way of example only with reference to the following drawings:

Figure 1 schematically represents a known device for monitoring characteristics associated with smoking a cigarette;

Figure 2 is a schematic diagram of a system for monitoring characteristics associated with the flow of aerosol from an aerosol delivery device in accordance with certain embodiments;

Figures 3 to 6 depict various parts of an apparatus for monitoring characteristics associated the flow of aerosol in accordance with certain embodiments based on the design represented in Figure 2.

Detailed Description

Aspects and features of certain examples and embodiments are discussed / described herein. Some aspects and features of certain examples and embodiments may be implemented conventionally and these are not discussed / described in detail in the interests of brevity. It will thus be appreciated that aspects and features of apparatus and methods discussed herein which are not described in detail may be implemented in accordance with any conventional techniques for implementing such aspects and features.

The present disclosure relates to methods and apparatus for monitoring the operation of aerosol (vapour) delivery / provision systems, such as an e-cigarette.

Throughout the following description the term "e-cigarette" may sometimes be used interchangeably with aerosol (vapour) delivery system / device / apparatus. However, it will be appreciated that embodiments of the invention may equally be applied to other forms of aerosol delivery device, for example, tobacco heated devices arranged to generate an aerosol from heating tobacco.

Figure 2 is a highly schematic diagram (not to scale and mostly, but not exclusively, representing elements in cross-section) of a system for monitoring characteristics associated the flow of aerosol from an aerosol delivery device in accordance with certain embodiments. Figures 3 to 6 depict various parts of an apparatus made according to the design of Figure 2 from various angles and in various states of disassembly. The apparatus is represented in Figure 2 in an orientation in which it is intended for normal use. For the purposes of describing various aspects of the apparatus, terms such as upper/top and lower/bottom will be used in respect of the orientation represented in Figure 2. Furthermore, the right-hand side of elements represented in the orientation of Figure 2 may sometimes be referred to as the upstream side and the left-hand side of elements represented in Figure 2 may sometimes be referred to as the downstream side, reflecting their arrangement with respect to the stream of aerosol flowing through the apparatus when in normal use.

The apparatus for monitoring aerosol delivery from an aerosol delivery device represented in Figure 2 comprises two main components, namely a holder component 20 and a data-processing component 21. Also schematically shown in Figure 2 is an aerosol delivery device 22, which in this example comprises an e-cigarette. The exact nature of the aerosol delivery device is not significant, and the apparatus may be used for monitoring aerosol delivery from different types and configuration of e-cigarette, and more generally from different types of aerosol delivery device, such as tobacco heated devices that generate an aerosol by heating tobacco. In this regard, certain embodiments may be primarily utilised for monitoring characteristics of aerosol delivery in the context of nicotine delivery systems.

Although the holder component 20 and the data-processing component 21 are schematically represented in Figure 2 as discrete elements of the system, it will be appreciated that different aspects of these components may be combined together or provided in separate units in accordance with different implementations. For example, in one implementation a single unit may provide the functionality of the holder component 20 and the data-processing component 21. For example, the data-processing component 21 may be contained within a handle of the holder component 20 (along with an appropriate power source) to provide a self-contained portable version of the apparatus. However, for the implementation represented in Figure 2 the data-processing component 21 is remote from the holder component 20 with appropriate connections therebetween.

The holder component 20 comprises a main body 24 (represented with zigzag hatching in Figure 2) which is generally tubular. The interior of the main body 24 defines a measurement chamber in a flow path extending from an aerosol-input end 23 on the upstream side of the holder component 20 to a mouthpiece 28 on the downstream side of the holder component 20. Aerosol drawn into the aerosol-input end of 23 of the holder component 20 from the aerosol delivery device 22 as a user puffs (inhales) on the mouthpiece 28 thus flows along the flow path, through the measurement chamber and out through the mouthpiece 28. The main body 24 in this example has a characteristic size of around 2 cm in length and 2 cm in diameter and is machined from Delrin (RTM). However, the main body 24 could equally be machined or moulded / cast from another material in accordance with conventional manufacturing techniques and may have different dimensions in different implementations.

The mouthpiece 28 (represented by diagonal hatching in Figure 2) is generally circularly symmetric and comprises a flange portion that abuts the downstream end of the main body 24 and is attached thereto by suitable fixings, such as bolts 27 running into appropriately tapped holes in the main body 24. On the upstream side of the flange portion of the mouthpiece 28 (i.e. to the right in Figure 2) is a first tubular portion of the mouthpiece 28 which extends into the bore of the main body 24. On the downstream side of the flange portion of the mouthpiece 28 (i.e. to the left in Figure 2) is a second tubular portion of the mouthpiece 28 which extends away from the main body 24. In principle a user may insert the second tubular portion of the mouthpiece 28 into their mouth in order to puff aerosol from the aerosol delivery device 22 via the airflow path running through the holder component 20. However, in practice, for hygiene reasons, the mouthpiece 28 in this example is provided with a disposable extension tube 31 which may be placed over the second tubular portion of the mouthpiece 28. After use the disposable extension tube 31 may thus be removed and a new replacement extension tube 31 connected to the mouthpiece. In this example the second tubular portion of the mouthpiece 28 is provided with an O-ring seal 29 to help provide an airtight coupling between the disposable extension tube 31 and the other part of the mouthpiece 28. The mouthpiece 28 (excluding the disposable extension tube 31) in this example has a characteristic size of around 3 cm in length and 2 cm in diameter (at its flange) and is again machined from Delrin (RTM). However, and as for the main body 24, the mouthpiece 28 could equally be machined or moulded / cast from another material in accordance with conventional manufacturing techniques and may have different dimensions in different implementations.

Upstream of the main body 24 is a diffusion element 30 (represented by dotted hatching in Figure 2). The diffusion element 30 is arranged between the aerosol-input end 23 of the holder component 20 and the measurement chamber within the main body 24 in order to help diffuse (disperse / mix) the flow of aerosol entering the flow path from the aerosol delivery device before it reaches the measurement chamber. In this example the diffusion element 30 is in the form of an extension tube that provides an extension to the flow path between the aerosol-input end 23 of the holder component and the measurement chamber within the main body 24 in which aerosol from the aerosol delivery device 22 can defuse as it travels along the flow path. The inventors have recognised the nature of aerosol delivery devices is such that the flow of aerosol at the output of the delivery system is sometimes in the form of a relatively narrow jet, whereas improved measurement results can be obtained if this jet is diffused / dispersed into a more uniform flow of aerosol along the flow path before reaching the measurement chamber. The length of the extension tube corresponding to the diffusion element 30 may be chosen according to the amount of diffusion / dispersion desired. Typically a longer extension tube will provide a greater degree of diffusion. Thus, the dispersion element may comprise an extension tube with a length selected from the group comprising: at least 1 cm; at least 2 cm; at least 3 cm; at least 4 cm; and at least 5cm. In some examples the diffusion element may instead of comprising an extension tube, or in addition to comprising an extension tube, comprise one or more baffles arranged in the flow path between the aerosol delivery device and the measurement chamber to help disrupt the jet of aerosol received from the aerosol delivery device and create a more uniform flow of aerosol in the flow path.

The diffusion element 30 is generally circularly symmetric and comprises a flange portion that abuts the upstream end of the main body 24. On the upstream side of the flange portion is a first tubular portion of the diffusion element which extends away from the main body 24. On the downstream side of the flange portion of the diffusion element 30 is a second tubular portion which extends into the bore of the main body 24. A resilient seal, in this case provided by two O-rings 32, is arranged between the second tubular portion and the bore of the main body to help achieve an airtight seal and to help hold the diffusion element 30 in place. That is to say, in this example the diffusion element 30 is simply pushed in to the central bore of the main body 24 and held in place by friction. However, it will be appreciated that additional fixing means may be provided in other implementations, for example a bolt arrangement corresponding to that used for the mouthpiece 28 or another suitable clamping mechanism could be used. An aerosol output end 22A of the aerosol delivery device 22 is coupled to the upstream end of the diffusion element 30 (corresponding to the aerosol-input end 23 of the holder component 20) using a flexible tube connector 34, for example a short length of silicone tubing. The diffusion element 30 in this example has a characteristic size of around 2.5 cm in length, of which around 1.5 cm comprises an extension to the flow path outside the main body. The diffusion element 30 in this particular example is around 2 cm in diameter (at its flange). As with the main body 24 and mouthpiece 28, the diffusion element 30 in this example is again machined from Delrin (RTM) but could equally be machined or moulded / cast from another material in accordance with

conventional manufacturing techniques and could again have different dimensions in different implementations.

The combination of the mouthpiece 28, main body 24 and diffusion element 30 (and the associated elements within these components) may in some respects be referred to as a head part of the holder component 20. The holder component 20 further comprises a handle 25, 26 for supporting the head part. The handle comprises a handle shaft 25 and a mounting bracket 26 for attaching the head part to the handle shaft.

The handle shaft 25 is the part of the holder component 20 which is gripped by a user when holding the device in normal use and is sized and shaped accordingly. Thus, the main shaft 25 may have generally a cylindrical shape with a diameter of around 2 cm and a length of around 10 cm and be made from any suitable material, such as plastic or metal. In this example the handle shaft 25 is hollow so that tubing and electrical connections to the head part can be routed through the handle shaft (as schematically shown in Figure 2 for the pressure tubes identified by reference numerals 44 and 46 and which are discussed further below).

The mounting bracket 26 in this example is in the form of an L-shape member formed from metal with a width of around 2.5 cm. A horizontal arm of the mounting bracket (for the orientation represented in Figure 2) has a length of around 2.5 cm and is fixed to the top of the handle shaft 25 and includes an opening so that any tubing / electrical connections running through the handle shaft 25 can pass through the mounting bracket 26. The mounting bracket 26 can be attached to the handle shaft 25 in any suitable way, for example the handle shaft may include an upwardly-extending threaded portion which passes through the opening in the horizontal arm of the mounting bracket 26 and a bolt threaded onto the upwardly-extending threaded portion may be used to clamp the mounting bracket 26 to the handle shaft 25. A vertical arm of the mounting bracket (for the orientation represented in Figure 2) has a length of around 3 cm and includes an opening into which a reduced diameter portion of the downstream end of the main housing 24 is received (e.g., as seen in Figure 5). Accordingly, when the mouthpiece 28 is fixed to the main housing 24, the vertical arm of the mounting bracket is in effect sandwiched/clamped between them, thereby mounting the head part to the mounting bracket 26. It will be appreciated the orientation of the handle relative to the head part can be adjusted by rotating the handle around the main body before being clamped in position by attaching the mouthpiece 28. There are many other ways in which the head part of the holder component 20 could be mounted to its handle. For example, a similar configuration to that represented in Figure 2 could be adopted with a mounting bracket being clamped between the main body 24 and the diffusion element 30 instead of between the main body 24 and the mouthpiece 28. More generally, any form of suitable clamping arrangement can be adopted for holding the head part to the handle.

Mounted to the handle shaft 25 of the handle is a support arm 52 extending away from the handle shaft 25 in the upstream direction. In this example the support arm 52 comprises a metal rod, for example with a diameter of around 5 mm. The support arm 52 is adjustably mounted to the handle with an appropriate clamping mechanism. In this example the clamping mechanism comprises a pair of semi-circular elements which can be fixed together around the handle at a desired position. The support arm 52 has a threaded portion screwed into a correspondingly threaded hole in one of the semi-circular elements of the clamping mechanism and a lock nut may be applied to help keep these elements together (e.g. as seen Figures 3 and 4). Mounted to the support arm 52 is a support cradle 54 extending upwardly (for the orientation represented in Figure 2). The aerosol delivery device 22 coupled to the aerosol-input end 23 of the holder component 20 during use may thus be supported relative to the handle 25, 26 via the support arm 52 and support cradle 54. The position of the support cradle 54 may be adjusted to accommodate different sizes of aerosol delivery device that may be used in conjunction with the apparatus described herein.

Accordingly, the cradle support 54 may be clamped to the support arm 52 at different positions along the length of the support arm 52. Furthermore, the support arm 52 may be positioned at a desired height relative to the handle shaft 25 before being clamped thereto. In this example the cradle support 54 includes a generally U-shaped opening for receiving the aerosol delivery device 22, and further includes bolts extending inwards through the sides of the U-shape to help clamp the aerosol delivery device 22 in position (e.g. as seen in Figure 6).

Thus the handle 25, 26 and the associated support 52, 54 for the aerosol delivery device 22 provides a mechanism by which a user can comfortably hold the holder component and aerosol delivery device 22 as a combined unit.

The apparatus for monitoring aerosol delivery in accordance with embodiments of the invention such as represented in Figure 2 includes a sensor arrangement for measuring a drop in pressure along a part of the flow path within the measurement chamber. In accordance with certain embodiments the sensor arrangement comprises a first pressure sensor / transducer 48 and a second pressure sensor / transducer 50 which are arranged to measure pressure at two locations in the flow path in the measurement chamber. The first and second pressure sensors 48, 50 may be based on any conventional pressure sensing technology, and in this example are mounted remotely from the holder component 20 as elements of the data-processing component 21. However, the pressure sensors 48, 50 could equally be integral with the holder component, for example they could be mounted within the handle shaft 25.

The first pressure sensor 48 is connected by first flexible plastic tube 44 to a first passageway 40 extending through the main body 24 and opening into the measurement chamber in the vicinity of a first location along the flow path. This first location may be referred to as an upstream pressure measurement location and is schematically indicated by the label "A" in Figure 2. The second pressure sensor 50 is connected by second flexible plastic tube 46 to a second passageway 42 extending through the main body 24 and opening into the measurement chamber in the vicinity of a second location along the flow path. This second location may be referred to as a downstream pressure measurement location and is schematically indicated by the label "B" in Figure 2. For the specific configuration represented in Figure 2, the first tubular portion of the mouthpiece 28 extends into the bore of the main body 24 beyond the opening of the passageway 40 into the measurement chamber. Accordingly, the first tubular portion of the mouthpiece 28 is also provided with a passageway in the vicinity of the second location B.

The first tube 44 and second tube 46 may be connected to their respective passageways 42 and 44 in any conventional manner. In this particular example the first and second passageways 40, 42 are associated with first and second connection nozzles 44A, 44B mounted to the housing 24 and onto which the relevant tube can be pushed. The first and second connection nozzles 44A, 44B can be seen, for example, in Figure 6 with the tubes removed. The first and second tubes are routed through the handle of the holder component as schematically represented in Figure 2, before exiting from the bottom of the handle and connecting to the pressure sensors in the remote data-processing component 21. The first and second tubes in this example have an outer diameter of around 5 mm and an inner diameter of around 3 mm, and a length of around 50 cm. However, it will of course be appreciated the length of the tubing will be chosen according to the desired location of the data-processing unit 21 relative to the holder component 20 when the apparatus is in normal use.

Accordingly, the first pressure sensor 48 is in fluid communication with the upstream pressure measurement location A via the first tube 44 and the first passageway 40 and the second pressure sensor 50 is in fluid communication with the downstream pressure measurement location B via the second tube 46 and the second passageway 42 in the main body 24 (and the additional passageway in the mouthpiece that is aligned with the second passageway in the main body 24). Between the upstream pressure measurement location A and the downstream pressure measurement location B within the measurement chamber is a flow-restrictor plate (orifice plate) 36. This comprises a metal disc with a diameter matching the inner bore of the main body 24 between the upstream and downstream pressure measurement locations A, B. The metal disc has a thickness of around 2 mm and is provided with a central hole 38 passing through the disc with a diameter of around 2 mm. The inner diameter of the bore through the main body 24 includes a shoulder against which the upstream side flow- restrictor plate abuts to define its position between the upstream and downstream pressure measurement locations A, B. The tubular portion of the mouthpiece 28 extending into the bore of the main body 24 is dimensioned so as to abut the downstream side of the flow- restrictor plate 36 when the mouthpiece is attached to the main body 24, thereby holding the restrictor plate in its position. However, it will be appreciated the restrictor plate could be held in position in various other ways, for example the shoulder of the inner wall of the main body against which the restrictor plate abuts may be provided on the downstream side while a portion of the diffusion element 30 extending into the bore of the main body 24 abuts the upstream side of the restrictor plate 36.

Thus, the first pressure sensor 48 is arranged to measure pressure at the upstream pressure measurement location A on the upstream side of the flow-restrictor plate 36 and the second pressure sensor 50 is arranged to measure pressure at the downstream pressure measurement location B on the downstream side of the flow-restrictor plate 36. From these measurements of pressure, and taking account of the size of the hole 38 in the flow restrictor plate 36, an estimate of flow rate can be determined in accordance with conventional techniques. Similarly, other characteristics relating to the flow of aerosol during use can be derived, for example the flow rate can be integrated to provide measurements of volumes of aerosol puffed by a user, for example on a per-puff basis or a per-session basis. Overall, the types of information that may be derived from the pressure measurements may correspond with the types of information conventionally derived from pressure

measurements in such devices used for analysing smoking behaviour and may be derived in the usual way. Thus, signalling representing pressure measurements from the pressure sensors 48, 50 are received by a processor 51 in the data-processing unit 21 for analysis and further processing. In general, and as noted above, the data from these pressure sensors may be processed in accordance with conventional techniques, for example as applied for a conventional smoking behaviour analyser of the kind represented in Figure 1 and described in WO 2004/047570 [1] and WO 2002/098245 [2]. That is to say, what is significant about certain embodiments is not the manner in which the pressure measurement data are processed, since this may be conventional, but the manner in which the apparatus is configured to improve on the accuracy of the measurements having regard to the nature of aerosol delivery devices as compared to conventional cigarettes. In this regard the data- processing unit 21 may be the same as used for conventional smoking behaviour analysis, for example, as envisaged in the document "A Device to Measure a Smoker's Puffing Topography and Real-Time Puff-by-Puff "Tar" Delivery", Beitrage zur Tabakforschung International Vol 26 No.2 July 2014 [3]. In this regard there are several aspects of arrangements such as those discussed herein which the inventors have found to provide improved performance for apparatus for monitoring aerosol delivery from aerosol delivery devices as compared to using designs conventionally used for monitoring smoking behaviour.

Although the examples described above have focused on approaches based on determining a difference in pressure along the flow path from separate pressure sensors / transducers coupled to the relevant locations along the flow path, it will be appreciated this could also be achieved using a single differential pressure sensor with its respective inputs coupled to the relevant locations. For example, a HCLA 12X5 E U differential pressure sensor from Sensortechnics could be used, although the specific hardware used to measure the difference in pressure along the flow path is not significant. In addition to measuring a pressure difference along the flow path, it can also be useful in some circumstances to measure a difference in pressure relative to the surrounding atmosphere. Accordingly, in one implementation a first differential pressure sensor may be coupled to the two locations along the flow path on either side of the orifice plate, whilst a second differential pressure sensor may be coupled to one side of the orifice plate, for example the upstream side, and to the surrounding atmosphere.

Thus the pressure sensor(s) may be considered to comprise a pressure sensor arrangement which in some examples may comprise a first pressure sensor coupled to the first location and a second pressure sensor coupled to the second location and in some other examples may comprise a differential pressure sensor with its inputs connected to the first and second locations.

One significant aspect of arrangements in accordance with some implementations of embodiments of the present disclosure is that the openings of the passageways 40, 42 into the measurement chamber (i.e. the pressure sensing ports) are arranged in an upper portion of the measurement chamber (i.e. offset from the lowest point in the measurement chamber), for example in an upper half of the measurement chamber when the device is oriented for normal use. In the particular example represented in Figure 2, the openings of the passageways 40, 42 into the measurement chamber are at the top of the measurement chamber. Thus, the respective first and second tubes 44, 46 are routed around the outside of the main body 24 from where they emerge from the top of the handle shaft 25 to connect to the respective passageways 40, 42 in the upper half of the main body 24. Accordingly, the orientation of the handle 25, 26 is selected to support the main body of the apparatus in an orientation in which the first and second openings (sensing ports) are in an upper portion of the measurement chamber when the apparatus is being held by a user in normal use. In the example represented in Figure 2, the handle 25, 26 is shown extending directly downwards. Thus, a user would hold the handle in the vertical direction when using the apparatus in this configuration. However, some users may find it more comfortable to hold the handle at a different angle, for example an inclined angle according to what they consider to be a more relaxed pose, furthermore different users may prefer the handle to be angled to different sides of the vertical, for example according to whether the user is left or right handed. In this regard, the mounting arrangement described above means the handle 25, 26 is moveable relative to the main body 24 so the handle can be moved to support the main body with the first and second openings in an upper portion of the measurement chamber for different ways of holding the apparatus in normal use. This can be achieved by simply rotating the handle to a desired orientation relative to the main body before the main body 24 is clamped to the mounting bracket 26 by attaching the mouthpiece 28.

This approach of providing the pressure sensing ports in an upper portion of the measurement chamber is different from known approaches in which the pressure sensing ports are arranged at the bottom of the measurement chamber. The inventors have recognised an advantage of this approach when using these kinds of devices for monitoring aerosol delivery, as opposed to smoke delivery, is a reduced likelihood of clogging of the openings / sensor ports which can be detrimental to the accuracy of the pressure

measurements. This issue arises because aerosols are more likely to form condensates inside the measurement chamber during use, and these condensates will typically flow towards the bottom of the measurement chamber under gravity. By providing the sensor ports in an upper portion of the measurement chamber the condensation of aerosol inside the measurement chamber is less likely to interfere with the pressure measurements, thereby providing more reliable results.

Another significant aspect of arrangements in accordance with some

implementations of embodiments of the present disclosure is the addition of the diffusion element 30. As already mentioned above, the inventors have recognised aerosol delivery devices tend to provide a jet-like output of aerosol, as opposed to the more uniform / diffuse output to be seen from conventional cigarettes. The inventors have recognised that directing the jet of aerosol from the aerosol delivery device directly into the measurement chamber without an intervening diffusion element can in some circumstances lead to unreliable pressure measurement results. This can happen, for example, when a non-diffused jet of aerosol from the aerosol delivery device passes directly through the orifice in a flow restrictor plate. Another significant aspect of arrangements in accordance with some

implementations of embodiments of the present disclosure is that the mouthpiece 28 and/or diffusion element 30 are removably mounted to the main body. This allows for the

components of the head part of the holder component 20 to be readily disassembled for cleaning. This can be important for devices for monitoring aerosol delivery, as opposed to smoke delivery, because of the increased tendency for aerosols to condense within the measurement chamber.

Yet another significant aspect of arrangements in accordance with some

implementations of embodiments of the present disclosure is the provision of a mechanism for supporting an attached aerosol delivery device 22 relative to the holder component 20 using the support of 52 and support cradle 54. The addition of such a support when compared to existing apparatus for analysing smoking behaviour can be useful in certain situations because an aerosol delivery device can oftentimes be significantly larger and weightier than conventional cigarettes.

Thus, it will be appreciated there are various aspects of the embodiments described herein which can help provide improved apparatus and methods for monitoring one or more characteristics of aerosol delivery from an aerosol delivery device, such as a nicotine delivery device (e.g. an e-cigarette). It will further be appreciated that whilst an embodiment including various features in combination has primarily been described, the various different features are independently beneficial and different example embodiments may include some but not all of the different features discussed above. For example, some implementations may include a diffusion element, but may not have the sensor ports in a upper portion of the measurement chamber, for example because the nature of the aerosol delivery device to be used is such that condensation within the measuring chamber is not expected to be problematic.

More generally, some implementations may comprise a support of the kind described above with or without any of the features relating to the orientation of the sensor ports, the diffusion element, or the removable elements to aid cleaning. Some other implementations may include removable elements to aid cleaning as discussed above, regardless of whether or not they also include features relating to the orientation of the sensor ports, the diffusion element or the support. Some other implementations may include a diffusion element, and may or may not include features relating to the orientation of the sensor ports, the support or the removable elements to aid cleaning. Still other implementations may include the feature of the sensor port openings being provided in an upper portion of the measurement chamber when in normal use, and may or may not include features relating to the diffusion element the support or the removable elements to aid cleaning. It will further be appreciated that certain implementations may include additional features. For example, in addition to the arrangement for sensing pressure in the

measurement chamber as discussed above, in some implementations the apparatus may also be provided with an optical sensor for measuring the density of aerosol in the measurement chamber. Such a sensor may be based on conventional techniques, for example using a light emitter, such as an LED, facing a light receiver, such as a photodiode, such that light from the LED is received by the photodiode after passing through aerosol in the flow path. In general, such a light-extinction sensor can be provided in accordance with conventional techniques. Wiring associated with the light-extinction sensor can, as with the tubing 44, 46, be routed through the handle of the holder component 22 to the data processing component 21 so that associated measurement signals can be processed by the processor 51 in accordance with conventional techniques. In such a case there may be wiring around the outside of the main body 24 associated with the LED / photodiode and to protect this wiring from damage an outer cover, e.g. a plastic cover, may be provided around the main body. An example of such a plastic cover is apparent in the embodiment represented Figures 3 to 6 as a black ring around part of the main body 24.

It will further be appreciated that while various elements of the apparatus described above are provided as separate elements, in other implementations the various elements of the apparatus may be provided as a single unit. For example, the diffusion element 30 and the main body 24 may, in some cases, be formed of a single machined / moulded unit (e.g. the diffusion element 30 may not comprise a separately removable part of the apparatus).

The inventors have analysed the performance of an apparatus for monitoring characteristics of aerosol delivery from an aerosol delivery device of the kind shown in Figures 2 to 6 by making measurements with a calibrated source of aerosol. This was done by drawing a range of different known volumes of aerosol from e-cigarettes through the apparatus to represent different sizes of user puffs with various durations. The apparatus was used to estimate the volume of each puff and was found in each case to estimate a volume that corresponded well with the known calibration volume.

Thus there has been described an apparatus for measuring the flow of aerosol from an aerosol delivery device, such as an e-cigarette. The apparatus comprises a main body defining a measurement chamber in a flow path extending from an aerosol-input end of the apparatus to a mouthpiece end of the apparatus. When in use, aerosol drawn into the aerosol-input end of the apparatus from an aerosol delivery device flows along the flow path and through the measurement chamber and out through the mouthpiece end of the apparatus. The apparatus further comprises a sensor for measuring a drop in pressure along a part of the flow path within the measurement chamber to allow characteristics of aerosol flow along the flow path to be measured, (e.g. flow rate, puff volumes, etc.). Thus, a user may use the aerosol delivery device (i.e. puff (inhale) aerosol generated by the aerosol delivery device) via the monitoring apparatus to allow characteristics relating to the delivery of aerosol to be monitored during use (e.g. flow rate, puff volumes and timings, etc.). The apparatus further comprises a diffusion element arranged between the aerosol-input end of the apparatus and the measurement chamber to diffuse / disperse the flow of aerosol from an attached aerosol delivery device within the flow path before it reaches the measurement chamber. The diffusion element (dispersion element) may, for example, comprise an extension tube providing an extended section of flow path between the aerosol-input end of the apparatus and the measurement chamber.

In order to address various issues and advance the art, this disclosure shows by way of illustration various embodiments in which the claimed invention(s) may be practiced. The advantages and features of the disclosure are of a representative sample of embodiments only, and are not exhaustive and/or exclusive. They are presented only to assist in understanding and to teach the claimed invention(s). It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects of the disclosure are not to be considered limitations on the disclosure as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and modifications may be made without departing from the scope of the claims. Various embodiments may suitably comprise, consist of, or consist essentially of, various

combinations of the disclosed elements, components, features, parts, steps, means, etc. other than those specifically described herein, and it will thus be appreciated that features of the dependent claims may be combined with features of the independent claims in combinations other than those explicitly set out in the claims. The disclosure may include other inventions not presently claimed, but which may be claimed in future.

REFERENCES

WO 2004/047570

WO 2002/098245

A Device to Measure a Smoker's Puffing Topography and Real-Time Puff-by- Puff "Tar" Delivery, Beitrage zur Tabakforschung International Vol 26 No.2 July 2014

Claims

1. An apparatus for measuring the flow of aerosol from an aerosol delivery device; the apparatus comprising:

a main body defining a measurement chamber in a flow path extending from an aerosol-input end of the apparatus to a mouthpiece of the apparatus such that aerosol drawn into the aerosol-input end of the apparatus from an aerosol delivery device flows along the flow path and through the measurement chamber and out through the mouthpiece of the apparatus;

a sensor arrangement for measuring a drop in pressure along a part of the flow path within the measurement chamber; and

a diffusion element arranged between the aerosol-input end of the apparatus and the measurement chamber to diffuse the flow of aerosol entering the flow path from an aerosol delivery device before it reaches the measurement chamber.

2. The apparatus of claim 1 , wherein the diffusion element comprises an extension tube providing an extension to the flow path between the aerosol-input end of the apparatus and the measurement chamber.

3. The apparatus of claim 2, wherein the extension tube comprises a downstream tube portion mounted in a bore of the main body and an upstream tube portion extending away from the main body to the aerosol-input end of the apparatus.

4. The apparatus of claim 3, further comprising an O-ring seal between the downstream tube portion and the bore of the main body into which the downstream tube portion is mounted.

5. The apparatus of any of claims 2 to 4, wherein the extension tube comprises a flange portion abutting the main body of the apparatus.

6. The apparatus of any of claims 2 to 5, wherein the extension tube is arranged so the length of the flow path between the aerosol-input end of the apparatus and the part of the flow path along which the drop in pressure is measured within the measurement chamber is selected from the group comprising: at least 1 cm; at least 2 cm; at least 3 cm; at least 4 cm; and at least 5cm.

7. The apparatus of any preceding claim, wherein the diffusion element comprises one or more baffles arranged in the flow path between the aerosol-input end of the apparatus and the measurement chamber.

8. The apparatus of any preceding claim, further comprising a resilient tube for coupling the airflow path to an output of an aerosol delivery device.

9. The apparatus of any preceding claim, wherein at least a portion of the diffusion element and / or at least a portion of the mouthpiece is removeably mounted to the main body of the apparatus.

10. The apparatus of any preceding claim, wherein the sensor arrangement comprises a pressure sensor arrangement connected to a first passageway extending through the main body of the apparatus to a first opening at a first location along the flow path in the measurement chamber and connected to a second passageway extending through the main body of the apparatus to a second opening at a second location along the flow path in the measurement chamber, thereby allowing measurements of a difference in pressure in the measurement chamber between the vicinity of the first and second locations.

1 1. The apparatus of claim 10, wherein the first opening is connected to the pressure sensor arrangement via a first tube and the second opening is connected to the pressure sensor arrangement via a second tube.

12. The apparatus of claim 10 or 1 1 , further comprising a handle for a user to hold the apparatus, wherein the handle is arranged to support the main body of the apparatus in an orientation in which the first and second openings are in an upper portion of the

measurement chamber when the apparatus is being held by a user in normal use.

13. The apparatus of claim 12, wherein the upper portion of the measurement chamber is an upper half of the measurement chamber.

14. The apparatus of claim 12 or 13, wherein the handle is moveable relative to the main body so the handle can be moved to support the main body so the first and second openings are in an upper portion of the measurement chamber for different ways of holding the apparatus in normal use.

15. The apparatus of any of claims 12 to 14, wherein the handle comprises a bracket with a portion that is clamped between the main body and the mouthpiece or between the main body and the diffusion element to hold the main body to the handle.

16. The apparatus of claim 10 to 15, further comprising a flow-restrictor arranged in the flow path between the first and second locations.

17. The apparatus of claim 16, wherein the flow-restrictor comprises a through-hole in a flow-restrictor plate mounted in the measurement chamber.

18. The apparatus of claim 17, wherein the flow-restrictor plate abuts a shoulder provided on an inner wall of the main body so as to locate the flow-restrictor plate in the measurement chamber.

19. The apparatus of claim 18, wherein the shoulder is on the same side of the flow- restrictor plate as the aerosol-input end of the apparatus and the flow-restrictor plate is held against the shoulder by a part of the mouthpiece which extends into the main body of the apparatus or wherein the shoulder is on the same side of the flow-restrictor plate as the mouthpiece and the flow-restrictor plate is held against the shoulder by a part of diffusion element which extends into the main body of the apparatus.

20. The apparatus of any preceding claim, further comprising a support for holding an aerosol delivery device coupled to the aerosol-input end of the apparatus in place relative to the apparatus.

21. The apparatus of claim 20, wherein the apparatus comprises a handle for a user to hold the apparatus and the support for holding an aerosol delivery device coupled to the aerosol-input end of the apparatus is attached to this handle.

22. The apparatus of claim 20 or 21 , wherein the support comprises a support arm carrying a cradle for receiving an aerosol delivery device.

23. The apparatus of any of claims 20 to 22, wherein the support is adjustable to allow aerosol delivery devices of different sizes to be supported.

24. The apparatus of any preceding claim, further comprising an optical extinction sensor for measuring optical extinction in the measurement chamber.

25. The apparatus of any preceding claim, further comprising a processing unit for receiving signals from the sensor arrangement for measuring a drop in pressure along a part of the flow path within the measurement chamber and determining characteristics of the delivery of aerosol therefrom.

26. A method for measuring the flow of aerosol from an aerosol delivery device using an apparatus comprising: a main body defining a measurement chamber in a flow path extending from an aerosol-input end of the apparatus to a mouthpiece of the apparatus such that aerosol drawn into the aerosol-input end of the apparatus from the aerosol delivery device flows along the flow path and through the measurement chamber and out through the mouthpiece of the apparatus; a sensor arrangement for measuring a drop in pressure along a part of the flow path within the measurement chamber; and a diffusion element arranged between the aerosol-input end of the apparatus and the measurement chamber to diffuse the flow of aerosol entering the flow path from an aerosol delivery device before it reaches the measurement chamber, wherein the method comprises using the sensor arrangement to measure the drop in pressure along a part of the flow path within the measurement chamber, and determining one or more characteristics of the flow of aerosol from the aerosol delivery device therefrom.

27. An apparatus substantially as described hereinbefore described with reference to Figures 2 to 6 of the accompanying drawings.

28. A method substantially as described hereinbefore described with reference to Figures 2 to 6 of the accompanying drawings.