U.S. patent application number 17/604331 was filed with the patent office on 2022-07-07 for electronic aerosol provision device.
The applicant listed for this patent is Nicoventures Trading Limited. Invention is credited to Rory FRASER, Hanting QIN, Oriol STROPHAIR.
Application Number | 20220211114 17/604331 |
Document ID | / |
Family ID | 1000006259948 |
Filed Date | 2022-07-07 |
United States Patent
Application |
20220211114 |
Kind Code |
A1 |
FRASER; Rory ; et
al. |
July 7, 2022 |
ELECTRONIC AEROSOL PROVISION DEVICE
Abstract
An electronic aerosol provision system, comprising an air
pathway between an air inlet and an air outlet; and a vaporiser for
generating vapour into the air pathway; wherein the air pathway
between the air inlet and the vaporiser is configured to support
laminar airflow.
Inventors: |
FRASER; Rory; (London,
GB) ; STROPHAIR; Oriol; (London, GB) ; QIN;
Hanting; (London, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Nicoventures Trading Limited |
London |
|
GB |
|
|
Family ID: |
1000006259948 |
Appl. No.: |
17/604331 |
Filed: |
April 14, 2020 |
PCT Filed: |
April 14, 2020 |
PCT NO: |
PCT/GB2020/050949 |
371 Date: |
October 15, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A24F 40/10 20200101;
A24F 40/53 20200101; A24F 40/40 20200101 |
International
Class: |
A24F 40/53 20060101
A24F040/53; A24F 40/40 20060101 A24F040/40; A24F 40/10 20060101
A24F040/10 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 17, 2019 |
GB |
1905425.3 |
Claims
1. An electronic aerosol provision system, comprising: an air
pathway between an air inlet and an air outlet; and a vaporizer for
generating vapor into the air pathway; wherein the air pathway
between the air inlet and the vaporizer is configured to support
laminar airflow.
2. The electronic aerosol provision system of claim 1, wherein the
air pathway comprises a linear channel between the air inlet and
the vaporizer.
3. The electronic aerosol provision system of claim 1, wherein the
air pathway between the air inlet and the vaporizer includes one or
more curved portions, wherein each of the one or more curved
portions has a radius of curvature greater than 5 mm and preferably
greater than 15 mm.
4. The electronic aerosol provision system of claim 1, wherein the
air pathway between the air inlet and the vaporizer is
substantially free of obstructions that would introduce turbulence
into airflow along the air pathway.
5. The electronic aerosol provision system of claim 1, wherein the
air pathway between the air inlet and the vaporizer is defined by
one or more walls that are substantially free of topology that
would introduce turbulence into airflow along the air pathway.
6. The electronic aerosol provision system of claim 1, wherein the
air pathway between the vaporizer and the air outlet is configured
to support laminar air flow.
7. The electronic aerosol provision system of claim 1, further
comprising a facility to control turbulence within the air
pathway.
8. The electrical aerosol provision system of claim 7, wherein said
facility has at least first and second settings, the first setting
providing a higher proportion of laminar flow relative to
turbulence than the second setting.
9. The electrical aerosol provision system of claim 8, wherein the
first setting produces an aerosol having a smaller particle size
than the second setting.
10. The electrical aerosol provision system of claim 9, wherein the
first setting produces an aerosol having a median particle size
that is at least 10%, preferably at least 20%, smaller than the
median particle size of an aerosol produced by the second
setting.
11. The electrical aerosol provision system of claim 9, wherein the
first setting produces an aerosol having a median particle size
less than 1 micron and the second setting produces an aerosol
having a median particle size greater than 1 micron.
12. The aerosol provision system of claim 8, wherein the first
setting reduces particle coagulation compared to the second
setting.
13. The aerosol provision system of claim 8, wherein the first
setting reduces vapor deposition onto particles compared to the
second setting.
14. The electronic aerosol provision system of claim 7, wherein the
facility supports movement of the airflow pathway.
15. The electronic aerosol provision system of claim 14, wherein
the movement of the airflow pathway is configured to introduce or
remove a linear channel between the air inlet and the
vaporizer.
16. The electronic aerosol provision system of claim 7, wherein the
facility comprises an airflow divider for dividing a portion of the
air pathway into two or more channels.
17. The electronic aerosol provision system of claim 7, wherein the
facility comprises an aperture having multiple shapes.
18. The electronic aerosol provision system of claim 7, wherein the
facility comprises one or more structures that are introduced into
or altered within the air pathway.
19. The electronic aerosol provision system of claim 7, wherein the
electronic aerosol provision system is configured to maintain a
substantially constant airflow through the air pathway as the
facility provides different levels of turbulence.
20. The electronic aerosol provision system of claim 7, wherein the
facility can be set by a user to control turbulence.
21. An electronic aerosol provision system, comprising: an air
pathway between an air inlet and an air outlet; a vaporizer for
generating vapor into the air pathway; and a facility for adjusting
the air pathway to control turbulence within the air pathway.
22. A method of operating an electronic aerosol provision system,
comprising: providing an air pathway between an air inlet and an
air outlet and a vaporizer for generating vapor into the air
pathway; and adjusting the air pathway to control turbulence within
the air pathway.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a National Phase entry of PCT
Application No. PCT/GB2020/050949, filed Apr. 14, 2020, which claim
priority to GB 1905425.3, filed Apr. 17, 2019, the entire
disclosures of which are incorporated herein by reference.
FIELD
[0002] The present disclosure relates to an electronic aerosol
provision device.
BACKGROUND
[0003] A typical electronic aerosol provision device includes an
internal air path which provides a channel between one or more
inlets and one or more outlets. A user of the electronic aerosol
provision device inhales on the air outlet(s) to create an airflow
through the device along the channel from the air inlet(s) to the
air outlet(s).
[0004] An electronic aerosol provision device generally also
includes a source (precursor) material which is used for forming a
vapor or aerosol. For example, some devices include a reservoir of
liquid and a heater which is used to vaporize liquid from the
reservoir. In other devices, a heater may be used to generate
volatiles from a solid material, and these in turn form a vapor or
liquid. In some cases, the liquid or solid material may be provided
in a replaceable cartridge. The vapor or aerosol is usually
generated in, or migrates into, the channel from the air inlet(s)
to the air outlet(s), and is conveyed by the airflow along the
channel and out through the air outlet(s) for inhalation by a
user.
[0005] The user experience of such an electronic aerosol provision
device is dependent upon the vapor or aerosol that exits the device
for inhalation.
SUMMARY
[0006] The disclosure is defined in the appended claims.
[0007] The approach described herein provides an electronic aerosol
provision system comprising an air pathway between an air inlet and
an air outlet and a vaporizer for generating vapor into the air
pathway. The air pathway between the air inlet and the vaporizer is
configured to support laminar air flow.
[0008] The approach described herein provides an electronic aerosol
provision system, comprising an air pathway between an air inlet
and an air outlet, a vaporizer for generating vapor into the air
pathway, and a facility for adjusting the air pathway to control
turbulence within the air pathway.
[0009] It will be appreciated that features and aspects of the
disclosure described above in relation to the first and other
aspects of the disclosure are equally applicable to, and may be
combined with, embodiments of the disclosure according to other
aspects of the disclosure as appropriate, and not just in the
specific combinations described above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Various embodiments of the disclosure will now be described,
by way of example only, with reference to the accompanying
drawings, in which:
[0011] FIG. 1 shows an example electronic aerosol provision
system.
[0012] FIG. 2 shows an electronic aerosol provision system having a
linear airflow channel configured to support laminar airflow
according to the approach described herein.
[0013] FIG. 3 shows distributions of aerosol particle sizes
generated by an electronic aerosol provision system such as shown
in FIG. 1.
[0014] FIG. 4 shows distributions of aerosol particle sizes
generated by an electronic aerosol provision system such as shown
in FIG. 2.
[0015] FIG. 5 shows an electronic aerosol provision system having a
smoothly curved airflow channel configured to support laminar
airflow according to the approach described herein.
[0016] FIG. 6 shows an electronic aerosol provision system having a
facility for adjusting the air pathway to control turbulence
according to the approach described herein.
[0017] FIG. 7 shows another electronic aerosol provision system
having a facility for adjusting the air pathway to control
turbulence according to the approach described herein.
DETAILED DESCRIPTION
[0018] Aspects and features of various examples are described
herein. Some of these aspects and features may be implemented
conventionally and these may not be described in detail in the
interests of brevity. It will be appreciated that such aspects and
features which are not described in detail may be implemented in
accordance with suitable conventional techniques.
[0019] The present disclosure relates to electronic aerosol
provision systems, which may also be referred to as electronic
vapor provision systems, e-cigarettes, and so on. In the following
description, the terms "e-cigarette", "electronic cigarette",
"electronic aerosol provision system" and "electronic vapor
provision system" may be used interchangeably unless the context
demands otherwise. Likewise the terms "device" and "system" may be
used interchangeably, for example, an "electronic aerosol provision
system" should be regarded as the same as an "electronic aerosol
provision device", unless the context demands otherwise.
Furthermore, as is common in this technical field, the terms
"vapor" and "aerosol", and related terms such as "vaporize",
"aerosolise", and "volatilize", may likewise be used
interchangeably unless the context demands otherwise.
[0020] Such electronic aerosol provision systems/devices are often
provided in modular form, for example, comprising a control unit
and a cartomizer (the latter being a combination of a cartridge and
a vaporizer). The term electronic aerosol provision system/device
is used herein to denote one or more modules (such as the control
unit) that act (comprise components) to generate an aerosol or
vapor. Such a system/device may be configured to receive one or
more additional modules, for example, a module (cartridge)
containing liquid or other precursor to be vaporized, or may be
provided in combination with one or more additional modules.
[0021] One common configuration for an electronic aerosol provision
system/device having a modular assembly is to comprise a reusable
part (the main control unit) and a replaceable (disposable)
cartridge part, also referred to as a consumable. The replaceable
cartridge part often contains the vapor (aerosol) precursor
material and may (in some implementations) also contain a vaporizer
(aerosolizer) to form a cartomizer. The reusable part often
contains a power supply, for example, a rechargeable battery, and
control circuitry for the device/system. These parts may contain
further components depending on functionality. For example, the
reusable part may contain a user interface for receiving user input
and displaying operating status characteristics, while the
replaceable cartridge part may contain a temperature sensor for
helping to control the temperature of the vaporizer.
[0022] A cartridge part is usually electrically and mechanically
coupled to a control unit for use. When the vapor precursor
material in a cartridge is exhausted (fully consumed), or the user
wishes to switch to a different cartridge having (for example) a
different vapor precursor material, the cartridge may be removed
from the control unit and a replacement cartridge provided in its
place. Devices conforming to this type of two-part modular
configuration are sometimes referred to as two-part devices.
[0023] Some of the example devices/systems described herein are
based on an elongated two-part device/system that utilises
disposable cartridges. However, it will be appreciated that the
approach described herein may also be adopted for different
configurations of an electronic aerosol provision system/device,
for example, single-part devices or modular devices comprising more
than two parts, refillable devices and single-use disposable
devices. In addition, the approach described herein may be applied
to devices/systems having other geometries (not necessarily
elongate), for example, based on so-called box-mod high performance
devices that typically have more of a box-like shape.
[0024] FIG. 1 is a schematic cross-sectional representation of a
first electronic aerosol provision device 20. The e-cigarette 20
comprises two main sections, namely a control section 22 and a
cartridge section 24. In some implementations, the cartridge
section and the control section are separate parts which can be
detached from one another. In normal use, the control part 22 and
the cartridge part 24 are releasably coupled together at an
interface 26. When the cartridge part 24 is exhausted (after
depletion of an aerosol precursor material therein), or the user
wishes to switch to a different cartridge, the cartridge 24 may be
detached from the control part 22. The detached cartridge may then
be disposed of (if fully depleted) and a replacement cartridge
coupled to the control part. Another possibility is that the same
cartridge part 24 may be refilled and re-attached to the control
part 22. In other implementations, the cartridge part 24 might be
refillable in situ, i.e. while still attached to the control part
22 (in which case the cartridge section 24 might potentially be
permanently attached to the control section 22).
[0025] The interface 26 generally provides a structural
(mechanical), electrical and airflow path connection between the
control section 22 and the cartridge section 24. For example, the
interface 26 may provide appropriately arranged electrical contacts
for establishing various electrical connections between the two
sections. Likewise, the interface may support (define) an airflow
channel (path) between the two sections as appropriate.
[0026] It will be appreciated that other implementations of the
electronic aerosol provision system 20 may have a different
configuration; moreover, different features from different
implementations as described herein may be mixed together as
appropriate. For example, in some implementations, the control
section 22 and the cartridge section 24 might be fixed together
(rather than being detachable); as noted above, this might be the
case when the cartridge section 24 is re-Tillable in situ. In some
implementations, a vaporizer may be provided in the control section
22 rather than in the cartridge section 24, in which case the
interface 26 might be configured to support the transfer of a vapor
precursor (such as a liquid) from the cartridge section 24 to the
control section 22--but without necessarily supporting the transfer
of electrical power from the control section 22 to the cartridge
section 24. In some implementations, the interface 26 may support a
wireless transfer of power from the control section to the
cartridge section, for example, based on electromagnetic induction.
In this case, a direct physical (electrical) connection between the
control section 22 and the cartridge section 24 may not be
provided. Furthermore, in some implementations, the airflow path
through the electronic aerosol provision device 20 might not go
through the control section 22, hence the interface 26 might not
include an airflow channel connection between the control section
22 and the cartridge section 24. The skilled person will be aware
of various other potential modifications.
[0027] In the example of FIG. 1, the cartridge section 24 comprises
a cartridge housing 62 which may be made of plastic or any other
suitable material. The cartridge housing 62 supports other
components of the cartridge section 24 and provides a mechanical
interface with the control section 22 as part of interface 26. The
cartridge section includes an airflow channel (or pathway) 72 and a
mouthpiece 70 which defines an air outlet 71 from the airflow
channel 72.
[0028] Within the cartridge housing 62 is a reservoir 64 that
contains a liquid to provide a vapor precursor material; this is
often referred to as an e-liquid. The liquid reservoir 64 in the
device of FIG. 1 has an annular shape about (around) the airflow
channel 72. The shape of the reservoir 64 is defined by an outer
wall, provided by the cartridge housing 62, and an inner wall that
forms the outside or boundary of the airflow channel 72 through the
cartridge section 24. The reservoir 64 is closed at each end to
retain the e-liquid, by mouthpiece 70 at the downstream end of the
cartridge section 24 and by the housing 62 forming interface 26 at
the upstream end.
[0029] The cartridge section 24 further comprises a wick (liquid
transport element) 66 and a heater (vaporizer) 68. In the device
shown in FIG. 1, the wick 66 extends transversely across the
cartridge airflow channel 72, i.e. perpendicular to the airflow
direction along channel 72. Each end of the wick is configured to
draw liquid from the reservoir 64 through one or more openings in
the inner wall of the liquid reservoir 64. The e-liquid infiltrates
the wick 66 and is drawn along the wick 66 by capillary action
(i.e. wicking). The heater 68 may comprise an electrically
resistive wire coiled around the wick 66, for example a nickel
chrome alloy (Cr20Ni80) wire, and the wick 66 may comprise a glass
fibre bundle or a cotton fibre bundle. Many other options will be
apparent to the skilled person; for example, the wick might be made
of ceramic, the wick and heater coil might be arranged
longitudinally rather than transversely, there might be multiple
heater coils 68, there might be multiple wicks 66, the heater 68
may have a planar configuration, and so on.
[0030] During use, electrical power may be supplied to the heater
68 to vaporize an amount of e-liquid (vapor precursor material)
drawn to the vicinity of the heater 68 by the wick 66. The
vaporized e-liquid then becomes entrained in air drawn along the
cartridge airflow channel 72 towards the mouthpiece outlet 70 for
user inhalation. The rate at which e-liquid is vaporized by the
vaporizer (heater) 68 generally depends on the amount of power
supplied to the heater 68, as well as the wicking or liquid
transport capacity of wick 66. In some devices, the rate of vapor
generation (the vaporisation rate) can be adjusted by changing the
amount of power supplied to the heater 68, for example through the
use of pulse width or frequency modulation techniques. In general,
the e-liquid vapor formed by the heater 68 cools in the airflow
channel 72 and at least partially condenses into particles (small
droplets of liquid), thereby forming an aerosol. It is this aerosol
that is then inhaled by a user through mouthpiece outlets 71.
[0031] The control section 22 shown in FIG. 1 comprises an outer
housing 32 with an opening that defines an air inlet 48 for the
e-cigarette 20, a battery 46 for providing electrical power to
operate the e-cigarette 20, control circuitry 38 for controlling
and monitoring the operation of the e-cigarette 20, a user input
button 34 and a visual display indicator 44. The outer housing 32
is configured to receive the cartridge section 24, thereby
providing a smooth integration (union) of the two sections or parts
at the interface 26. For example, the outer housing 32 may include
clips or slots or any other suitable engagement features for
receiving corresponding features of the cartridge section 24.
[0032] The battery 46 is generally rechargeable such as through a
charging connector in the control section housing 32, e.g. a USB
connector (not shown in FIG. 1). The user input button 34 may be
used to perform various control functions. The display 44 may (for
example) comprise one or more LEDs for displaying information about
the charge status of the battery 46 or any other suitable
information or indication. In some implementations, the user input
button 34 and the display 44 may be integrated as a single
component. The control circuitry 38 is suitably configured
(programmed) to control the operation of the electronic cigarette,
for example to regulate the supply of power from the battery 46 to
the heater 68 for generating vapor.
[0033] The air inlet 48 connects to an airflow path 50 through the
control section 22. The control part section path 50 in turn
connects to the cartridge airflow channel 72 via the interface 26
when the control part 22 and cartridge part 24 are connected
together. Thus, when a user inhales on the mouthpiece 70, air is
drawn in through the air inlet 48, along the control section air
path 50, through the interface 26, along the cartridge airflow
channel 72, and out through the opening of the mouthpiece 70 for
user inhalation. In the example of FIG. 1, the airflow path 50 is
configured so that the airflow through air inlet 48 is
perpendicular to the airflow through the air outlet 71 during a
user inhalation. In particular, the air inlet 48 is arranged on a
side of the outer housing 32 (rather than the base). Such an air
inlet may be termed a side hole. The airflow path 50 incorporates a
corner or angle whereby the airflow during an inhalation
transitions sharply from a first direction of airflow from the air
inlet 48 to the corner to a second direction of airflow from the
corner to the interface 26. As can be seen in FIG. 1, the second
direction of travel is perpendicular to the first direction of
travel.
[0034] FIG. 2 is a schematic cross-sectional representation of a
second electronic aerosol provision device 200. The components of
the e-cigarette 200 of FIG. 2 are generally the same as or similar
to those described in relation to FIG. 1 (and labelled with like
reference numbers), and so these components will not be discussed
again. However, in contrast to the first e-cigarette 20 of FIG. 1,
which comprises a side hole air inlet 48, the second e-cigarette
200 of FIG. 2 comprises an air inlet 248 in the base (or bottom) of
the e-cigarette (where the orientation of an e-cigarette is defined
in the conventional manner such that the mouthpiece 71 is at the
top). With this location for the air inlet 248, the control section
airflow pathway 250 and the cartridge section airflow pathway 72
are coaxially aligned such that there is a straight air path along
the length of the airflow channel. Thus as shown in FIG. 2, the
airflow channels 250, 72 of electronic vapor provision device 200
are aligned such that airflow through the device from the air inlet
248 to the vaporizer 68 and then out through the mouthpiece 70
follows a substantially straight line (linear) pathway, i.e.
heading in substantially a single direction, without changing
direction, curving, bending, etc.
[0035] Although FIG. 2 shows one example in which the airflow
pathways in the control section 22 and in the cartridge section 24
have a coaxial (co-aligned) configuration, it will be appreciated
that such a configuration may be achieved differently in other
implementations. Furthermore, while e-cigarette 200 is shown as
having two modules (cartridge part 24 and control part 22), other
implementations with a coaxial configuration for airflow pathways
52 and 72 may be implemented as a one-piece device, or else as a
system comprising more than two modules.
[0036] The straight (linear) configuration of the airflow channel
250 through the control section 22 in FIG. 2, compared with the
angled (cornered) configuration in the airflow channel 50 of
e-cigarette 20 in FIG. 1, helps to support a laminar airflow within
the channel 250. In a laminar airflow (also referred to herein as a
linear airflow), the air generally all flows in parallel in the
same direction. For example, for laminar airflow along a
cylindrical pipe, all the air flows in parallel in an axial
direction along the pipe. The airflow velocity along the pipe has a
radial profile according to distance from the centre of the pipe.
The air flowing along the central axis of the pipe flows most
quickly, while the airflow velocity then gradually drops with
radial distance away from the centre to a zero velocity adjacent
the edge or wall of the pipe in a region referred to as the
boundary layer.
[0037] In contrast to laminar flow, the presence of features such
as corners, bends, obstructions, etc. along an airflow path
generally introduces turbulence into the airflow. This turbulent
airflow (also referred to herein as non-linear airflow) is created
by, and reflects, localised variations in air pressure and other
instabilities. For example, air flowing around (but close to) an
obstruction may have a higher pressure than air flowing further
away from the obstruction; this may then be balanced by a region of
relatively low pressure immediately after the obstruction.
Localised movements of air in effect seek to rebalance the air
pressure variations, and thereby introduce turbulence into the
airflow.
[0038] Note that turbulence may also arise even in an axially
aligned channel shown in FIG. 2. For example, if the air is pushed
through a pipe too quickly (i.e. with too great a pressure
difference), the high level of radial shear resulting from
different axial velocities at different radial distances out from
the centre of the channel disrupts the airflow, leading to
instabilities and other forms of turbulence.
[0039] A dimensionless parameter known as the Reynolds number (R)
is often used to characterise the laminar and turbulent flow
regimes. The Reynolds number is defined as R=uL/v, where u is the
flow speed, v the viscosity, and L is a linear scale size of the
flow (this might be the diameter of a pipe, for example). A low
Reynolds number will generally produce laminar flow, while a high
Reynolds number will generally produce turbulent flow. The
transition between laminar flow and turbulent flow might typically
occur for R in the range 2000-3000 (although this transition point
is typically sensitive to various factors, and may lie outside the
above range in some circumstances). Note that increasing the flow
speed increases the Reynolds number, and hence may induce a
transition to turbulent flow, as noted above. In contrast,
increasing the viscosity will decrease the Reynolds number; this
can be regarded as a higher viscosity damping out turbulent
motion.
[0040] FIGS. 3 and 4 are graphs showing the frequency distributions
of particle sizes produced by the first and second example
e-cigarettes, namely the side-hole device 20 of FIG. 1 and the
linear flow device 200 of FIG. 2 respectively. The particle size
refers to the size of particles or droplets in the vapor or aerosol
exiting the device through air outlets 71. Each graph shows ten
repeated measurements of the particle size distribution.
Statistical summaries of the frequency distribution of the particle
sizes for each measurement are provided in Tables 1 and 2
below.
TABLE-US-00001 TABLE 1 "Side-hole" e-cigarette Date - Time File
Cv(%) Dx(10) Dx(50) Dx(80) [V] 4 Dec. 2017 - 16:15:03.0384 171204
Side Hole r1 1.1 1.0014 0.39 1.12 2.56 [V] 4 Dec. 2017 -
16:15:32.9526 171204 Side Hole r1 1.2 0.0016 0.47 1.28 2.69 [V] 4
Dec. 2017 - 16:16:02.9672 171204 Side Hole r1 1.3 0.0016 0.63 1.44
3.00 [V] 4 Dec. 2017 - 16:16:33.0216 171204 Side Hole r1 1.4 0.0020
0.32 1.68 3.33 [V] 4 Dec. 2017 - 16:17:03.0560 171204 Side Hole r1
1.5 0.0016 0.65 1.50 3.15 [V] 4 Dec. 2017 - 16:17:33.0904 171204
Side Hole r1 1.6 0.0021 0.92 1.77 3.33 [V] 4 Dec. 2017 -
16:18:03.1246 171204 Side Hole r1 1.7 0.0016 0.86 1.71 3.32 [V] 4
Dec. 2017 - 16:18:33.1584 171204 Side Hole r1 1.8 0.0017 0.87 1.70
3.23 [V] 4 Dec. 2017 - 16:19:03.1926 171204 Side Hole r1 1.9 0.0017
0.74 1.55 3.08 [V] 4 Dec. 2017 - 16:19:33.2272 171204 Side Hole r1
1.10 0.0017 0.96 1.81 3.37 [V] = Volume [N] = Number
TABLE-US-00002 TABLE 2 "Direct linear flow" e-cigarette Date - Time
File Cv(%) Dx(10) Dx(50) Dx(80) [V] 14 Dec. 2017 - 11:56:39.4 . . .
171214 al bh beta 58 r1 1.1 0.0014 0.20 0.53 1.36 [V] 14 Dec. 2017
- 11:57:09.3 . . . 171214 al bh beta 58 r1 1.2 0.0011 0.23 0.62
1.53 [V] 14 Dec. 2017 - 11:57:39.3 . . . 171214 al bh beta 58 r1
1.3 0.0013 0.22 0.68 1.93 [V] 14 Dec. 2017 - 11:58:09.4 . . .
171214 al bh beta 58 r1 1.4 0.0012 0.27 0.85 1.24 [V] 14 Dec. 2017
- 11:58:39.4 . . . 171214 al bh beta 58 r1 1.5 0.0012 0.25 0.76
1.99 [V] 14 Dec. 2017 - 11:59:09.4 . . . 171214 al bh beta 58 r1
1.6 0.0011 0.23 0.72 2.15 [V] 14 Dec. 2017 - 11:59:39.5 . . .
171214 al bh beta 58 r1 1.7 0.0015 0.20 0.55 1.56 [V] 14 Dec. 2017
- 12:00:09.5 . . . 171214 al bh beta 58 r1 1.8 0.0015 0.22 0.65
1.91 [V] 14 Dec. 2017 - 12:00:39.5 . . . 171214 al bh beta 58 r1
1.9 0.0015 0.54 1.25 2.41 [V] 14 Dec. 2017 - 12:01:09.6 . . .
171214 al bh beta 58 r1 1.10 0.0014 0.30 0.97 2.47 [V] = Volume [N]
= Number
[0041] The final three columns of each Table define parameters of
the particle size distribution for that measurement. Thus in the
first line of Table 1, Dx(10)=0.39 implies that 10% of the
particles have a size less than 0.39 microns (.mu.m), Dx(50)=1.12
implies that 50% of the particles have a size less than 1.12
microns (.mu.m) (i.e. this is the median size), and Dx(00)=2.56
implies that 90% of the particles have a size less than 2.56
microns (.mu.m). A comparison of FIGS. 3 and 4 (and the associated
tables) clearly shows that the particle sizes are generally smaller
for a direct linear flow e-cigarette (such as shown in FIG. 2) than
for a side-hole e-cigarette (such as shown in FIG. 1). It is also
suggested that the direct linear flow measurements of FIG. 4
produce a slightly tighter (more compact) distribution than the
side-hole measurements of FIG. 3.
[0042] Without being bound by theory, it is considered that the
laminar (non-turbulent) airflow may form an aerosol having a
smaller particle size than the non-laminar (turbulent) airflow
because the turbulence causes more collisions between aerosol
particles, and such collisions may lead to coagulation between
particles and hence a growth in particle size. In contrast, when
the airflow is laminar, coagulation among particles might be
reduced since the airflow is substantially all in parallel, aligned
with the axial direction. Consequently, there is less mixing in the
airflow, and hence less potential for coagulation. It is also
possible that turbulence brings more vapor into contact with
particles, and hence leads to a faster condensation of vapor onto
the particles (compared with laminar flow), thereby leading to a
larger particles. This faster condensation of vapor onto the
existing particles may occur in addition to, or in place of, the
faster coagulation of particles.
[0043] It has been found that an enhanced user experience can be
achieved by an electronic vapor provision system that generally
provides an aerosol having a smaller particle size for inhalation
by the user. Without being bound by theory, this user preference
for a smaller particle size may arise from one or more factors,
such as easier absorption of the particles by tissue, increased
lightness or diffusiveness of the particles, greater uniformity
(consistency) of the particles, increased travel distance of the
particles, etc.
[0044] In view of this user preference, the airflow configuration
of the e-cigarette 200 of FIG. 2 is advantageous with respect to
the airflow configuration of the e-cigarette 20 of FIG. 1, because
the straight airflow channel 250 of FIG. 2 helps to provide laminar
airflow, and hence a smaller particle size, compared with the
angled airflow channel 50 of FIG. 1. In practice, in many actual
devices, the airflow may have both laminar and turbulent
components. Increasing the proportion of laminar components at the
expense of the turbulent components should still help promote a
reduced particle size and hence an improved user experience.
Accordingly, the benefits of providing a laminar flow are not
binary (all or nothing), but rather can be realised by
incrementally increasing the proportion of laminar flow in a given
device.
[0045] FIG. 5 is a schematic cross-sectional representation of a
third electronic aerosol provision device 500. The components of
the e-cigarette 500 of FIG. 5 are generally the same as or similar
to those described in relation to FIG. 1 (and labelled with like
reference numbers), and so these components will not be discussed
again. In contrast to the example e-cigarette 20 of FIG. 1, which
comprises a side hole air inlet 48 with an angled airflow channel
50, and also in contrast to the example e-cigarette 200 of FIG. 2,
which comprises an air inlet 248 in the base (or bottom) of the
e-cigarette 200 to provide a straight line (linear) airflow channel
250, the e-cigarette 500 of FIG. 5 comprises an airflow pathway 550
in the control section 22 which is side-opening 548 (like the
e-cigarette 20 of FIG. 1), but having a smooth, continuous curve
for the airflow channel 550 between the air inlet 548 (side-hole)
and the interface 26.
[0046] Configuring the airflow pathway 550 to have such a
continuous curve, rather than a sharp corner or angle, helps to
support laminar air flow. Thus implementing an air pathway 550
which imparts a gradual change in direction of the airflow allows
the device to comprise a side-hole but with a lower level of
turbulence (if any), compared with the configuration of FIG. 1. An
example e-cigarette 500 may therefore have an airflow channel 550
with a radius of curvature greater than 5 mm, greater than 10 mm,
or preferably greater than 15 mm, to reduce (or eliminate)
turbulence (compared with the configuration of FIG. 1), and so help
to reduce particle size in the aerosol provided by the device.
[0047] In some implementations, the continuous curve of the airflow
channel 550 may only extend part-way between the air inlet 548 and
the interface 26. For example, the airflow channel 550 may have a
smoothly curved portion near air inlet 548, followed by a linear
portion near the interface 26 (or conversely, the airflow channel
550 may have a smoothly curved portion near the interface 26,
following on from a linear portion near the air inlet 548). More
generally, there may be more than one continuous curve or more than
one linear section in the airflow channel 550. A further
possibility is that a continuous curve (or multiple such curves)
might be approximated by a sequence of short linear sections,
whereby the change in orientation of between any two successive
linear sections is small, for example, in the range of 1-5 degrees,
so as to limit or avoid the introduction of turbulence.
[0048] FIG. 6 is a schematic cross-sectional representation of a
fourth electronic aerosol provision device 600. The components of
the e-cigarette 600 of FIG. 6 are generally the same as or similar
to those described in relation to FIG. 1 (and labelled with like
reference numbers), and so these components will not be discussed
again. In contrast to the e-cigarettes shown in FIGS. 1, 2 and 5,
which have fixed airflow channel configurations, the e-cigarette
600 of FIG. 6 has an airflow pathway 650 which may be modified to
change the level of turbulence in air inhaled through the device.
In other words, the e-cigarette 600 of FIG. 6 includes a facility
to adjust the air pathway to control the amount of turbulence
within the air pathway, and hence to change the particle size
distribution in the aerosol produced by the e-cigarette 600.
[0049] The airflow channel 650 of e-cigarette 600 comprises two
sections, a first movable channel section 610 and a second fixed
section 610. These two sections are joined by an appropriate
coupling or connector 615. The first movable airflow channel
section 610 therefore extends from the air inlet 648 to the
coupling 615, while the second airflow channel section 611 extends
from the coupling 615 to the interface 26. The movable airflow
channel section 610 in effect is able to rotate about the coupling
615 to reposition the air inlet 648. In particular, the position of
the air inlet 648 can be rotated as indicated by the arrows between
position A and position A'. In position A', the e-cigarette 600
approximates the side-hole configuration shown in FIG. 1, while in
position A the e-cigarette 600 approximates the direct linear flow
(bottom hole) configuration shown in FIG. 2.
[0050] The e-cigarette 600 includes a switch or button 625 for a
user to rotate the movable section 610 between positions A and A'.
This switch 625 may be provided with a suitable mechanical coupling
(not shown) to accomplish this rotation of the movable section 610.
Another possibility is that the rotation of section 610 is
performed using electrical power from battery 46 (again under the
control of switch or button 625). Other actuation mechanisms may be
implemented, including direct movement by a user of the movable
section 610, in which case button/switch 625 might be omitted.
[0051] Although the e-cigarette 600 has been described above as
having two operational positions for movable section 610
corresponding to A and A' (so that the position shown in FIG. 6 is
transitional between these two operational positions), other
implementations may have one or more additional operational
positions intermediate A and A'. Some implementations may allow a
continuous adjustment, i.e. the movable section 610 can be located
at any desired position intermediate A and A'. It will be
appreciated that the portion 621 of the control section housing 32
in which air inlet 648 is formed will be arranged to accommodate
the desired range of positions for the air inlet 648.
[0052] By moving the position of the air inlet 648 from position A
to position A' (through any supported intermediate positions) an
increasing level of turbulence can be imparted to the
airflow--which as described above, will generally result in an
aerosol having a larger particle size. This provides users with
control over a parameter (particle size) which has a direct
physical impact on their experience of using the e-cigarette 600.
In particular, different particle sizes (large or small) may be
preferred by different users, or for different cartridges,
different e-liquids, or just in different user circumstances. The
use of button 625 to control the position of air inlet 648 by
moving section 610 to adjust turbulence provides users with a
control over aerosol particle size according to their specific
preferences and circumstances.
[0053] For example, in a first orientation, as indicated by
position A, the movable channel section 610 is co-aligned with the
remainder of the airflow channel 650, in particular fixed section
611, and so turbulence is minimised. In a second orientation, as
indicated by position A', the movable channel section 610 is now
perpendicular to the remainder of the airflow channel 650 and so
turbulence is introduced (or increased). Note that this mechanism
allows the level of turbulence to be altered with little or no
change to the overall flow rate. In particular, the size of the air
inlet 648 and hence the amount of air inhaled during a puff is
substantially maintained regardless of the orientation of the
movable channel section 610, however, the particle size
distribution for the puff is dependent on (and controlled by) the
location setting of the movable channel section 610.
[0054] As described above, the orientation of the movable airflow
section 610 may be selected by a user interacting with the device
through a mechanical switch 625 or similar device such as a wheel
or lever to allow the user to tailor the particle size to his/her
particular preference. In some implementations, this adjustment of
the movable airflow section 610 may be performed using the user
input button 34 or the visual display indicator 44 (in place of, or
additionally to, using switch 625). The changes to the orientation
may be performed very quickly, for example during or between puffs
(activations of the heater 68), thereby allowing the user to
quickly adjust the particle size to a desired setting. A further
possibility is that in some circumstances at least, the orientation
of the movable channel section 610 may be automatically performed
by the control circuitry 38, for example, after recognising that a
particular cartridge 24 containing a particular e-liquid has been
attached to the control unit 22.
[0055] FIG. 7 is a schematic cross-sectional representation of a
fifth electronic aerosol provision device 700. The components of
the e-cigarette 700 of FIG. 7 are generally the same as or similar
to those described in relation to FIG. 1 (and labelled with like
reference numbers), and so these components will not be discussed
again. More particularly, the e-cigarette 700 of FIG. 7 has a
configuration which is very similar the e-cigarette 200 of FIG. 2,
but further includes, like the e-cigarette 600 of FIG. 6, a
facility to adjust the particle size distribution in the aerosol
produced by the e-cigarette 700.
[0056] Thus as shown in FIG. 7, e-cigarette 700 comprises a fixed
airflow pathway 750 extending to air inlet 748 using a direct
linear flow configuration, the same as for e-cigarette 200 as shown
in FIG. 2. However, the e-cigarette 700 further includes a
mechanism 715 (shown in schematic form in FIG. 7) to alter the
configuration of the air pathway 750 so as to modify the relative
proportion of laminar and turbulent airflow within the air pathway
750, thereby providing some control over the resulting particle
size distribution of the aerosol produced by the e-cigarette 700.
The mechanism 715 may be operated by a user via button or switch
725 in a similar manner to the use of button 625 in e-cigarette 600
to move the airflow channel section 610. Likewise, the operation of
mechanism 715 might be performed using the user input button 34 or
the visual display indicator 44 (in place of, or additionally to,
using switch 725) or at least partly automatically by the control
circuitry 38.
[0057] One implementation of mechanism 715 is a shaped diaphragm or
aperture which may be changed, for example, between a simple
circular shape for the opening to a star shape (or any other more
complex shape) for the opening. The circular shape introduces
relative little turbulence, and hence supports a higher proportion
of laminar flow, whereas the more complex (detailed) star-shaped
aperture tends to introduce more turbulence by creating more
localised variations in pressure, and so leads to a lower
proportion of laminar flow. The switching between the different
aperture shapes may be actuated, for example, using button or
switch 725.
[0058] In other implementations, a wall feature, such as a baffle,
fin or other obstruction (or multiple such items) may be moved into
or out of the airflow path 750. Inserting such a feature can again
lead to more localised pressure variations that promote the
formation of turbulence. Accordingly, the level of turbulence (and
hence the resulting particle size) may be controlled by adjusting
the extent of the insertion or extraction of such obstructions into
the airflow channel 750 (e.g. by using button or switch 725). A
similar effect could be achieved, for example, by forming or
flattening surface texture or other topology on the inside walls of
the airflow channel 750.
[0059] Another potential implementation of mechanism 715 comprises
a grill, grating or other similar structure, which may be moved
into the airflow path 750 to increase the turbulence of the
airflow. Typically the grating is formed of fine wire, or similar,
such that the grating acts to disrupt and impart turbulence to the
airflow, but does not inhibit the airflow rate. In some
implementations, the grill 715 may be permanently located in the
airflow path 750, however, the configuration or some other property
(or properties) of the grill might be varied, such as the size of
individual openings within the grill, to change the amount of
turbulence produced in the airflow. A further example of mechanism
715 is an airflow divider, which may be positioned in the airflow
path 750 to divide the airflow channel into two or more
subchannels. Both the separation of the airflow into the multiple
air channels, and then the subsequent recombination of the airflow
into a single channel, may lead to the formation of turbulence in
the airflow. By varying the proportion of air in each component,
the level of turbulence may be controlled.
[0060] In some implementations, the mechanism 715 may not only
impact the relative proportion of laminar to turbulent flow, but
also the rate of airflow through the e-cigarette for a given
pressure drop or strength of inhalation--in effect, increasing the
resistance to draw (RTD). For example, introducing fins or other
obstructions into the airflow will generally act as additional RTD
resistance to the airflow, in addition to increasing the amount of
turbulence. It may be desirable however to allow a user to control
the amount of turbulence (and hence particle size) while making
little or no change to the RTD (and hence to the overall flow
rate). One way of achieving this is for the e-cigarette to include
a restrictor somewhere along the overall airflow path which is the
primary restriction on the airflow through the e-cigarette. In such
a configuration, any changes in RTD caused by different settings of
the mechanism 715 will have a relatively low impact on the overall
RTD experienced by a user. Another approach is for the different
settings of the mechanism 715 to be designed to alter the amount of
turbulence, but not the overall airflow resistance. For example,
for the implementation discussed above using a circular aperture to
reduce turbulence and a star-shaped aperture to increase
turbulence, the sizes of the circular and star-shaped apertures may
be arranged so as to provide the same airflow resistance (RTD
contribution) for both apertures.
[0061] Although mechanism 715 is shown in FIG. 7 as implemented in
the middle of airflow channel 750, it may instead be implemented at
the air inlet 748 or the interface 26, or at any suitable location
between the air inlet 748 and the interface 26. In some
implementations, the mechanism 715 may comprise multiple components
at various locations along the air pathway 750. Alternatively, the
mechanism 715 may stretch along a substantial portion (e.g. most or
all) of the airflow channel 750 between the air inlet 748 and the
interface 26. Furthermore, while the air pathway 750 shown in FIG.
7 is substantially linear (a straight line), other implementations
may have a curved air pathway, for example, similar to the shape
shown in FIG. 5 for e-cigarette 500.
[0062] As described above, the present approach provides an
electronic aerosol provision system or device comprising: an air
pathway between an air inlet and an air outlet; and a vaporizer for
generating vapor into the air pathway. The air pathway between the
air inlet and the vaporizer is configured to support laminar
airflow.
[0063] It has been found that such a laminar airflow can lead to
smaller aerosol particles exiting the electronic aerosol provision
system, which in turn can lead to a more favourable user
experience. It is believed (without limitation) that a laminar
airflow may produce a smaller particle size by reducing particle
coagulation or by reducing vapor deposition onto particles.
Although these physical effects generally happen downstream of the
vaporizer, it is difficult to quiesce an airflow within the
electronic aerosol provision system which is already turbulent.
Accordingly the approach described herein seeks to prevent or
reduce the formation of turbulence upstream of the vaporizer, which
then helps to prevent or reduce turbulence at (and downstream of)
the vaporizer.
[0064] An ideal device might have laminar (non-turbulent) airflow
along the entire airflow pathway within the device, from air inlet
to air outlet. However, it may be difficult in practice to achieve
completely laminar airflow within the device, rather the air
pathway between the air inlet and the vaporizer may be configured
to support substantially (mostly) laminar airflow, for example,
having at least 60%, 75%, 85%, 90% or 95% of the airflow through
the electronic aerosol provision device being laminar.
[0065] There are various ways in which the air pathway, at least
between the air inlet and the vaporizer, may be configured to
support (mostly) laminar airflow. For example, the air pathway may
comprise a linear (straight line) channel between the air inlet and
the vaporizer; the absence of sharp bends or angles facilitates
laminar flow. In some cases the air pathway between the air inlet
and the vaporizer may include one or more curved portions; each of
the one or more curved portions may have a radius of curvature
greater than 5 mm and preferably greater than 15 mm. Again, the
provision of gentle curves rather than sharp bends or angles
facilitates laminar flow (and also gives more flexibility in the
overall geometry of the device compared with having a straight line
airflow). Laminar flow along the air pathway between the air inlet
and the vaporizer may be further facilitated by ensuring this
pathway is substantially free of (i) obstructions, for example,
protrusions, grills, narrow apertures, etc., or (ii) topology for
the walls of the air pathway, for example, surface texturing or
other features, that would introduce turbulence into airflow along
the air pathway. It will be appreciated that a similar approach may
be adopted for the portion of the air pathway downstream of the
vaporizer in order to reduce or prevent turbulence in this
downstream portion.
[0066] The present approach also provides an electronic aerosol
provision system (e.g. such as described above) which comprises a
facility to control turbulence within the air pathway. In some
implementations, the facility provides at least first and second
settings, the first setting providing an airflow with a higher
proportion of laminar flow relative to turbulence than the second
setting. As noted above, the first setting will generally therefore
produce an aerosol having a smaller particle size than the second
setting. For example, the first setting may produce an aerosol
having a median particle size (e.g. based on diameter) that is at
least 10%, preferably at least 20%, smaller than the median
particle size of an aerosol produced by the second setting, or the
first setting produces an aerosol having a median particle size
less than 1 micron and the second setting produces an aerosol
having a median particle size greater than 1 micron. (It will be
appreciated that these ratios/sizings are given by way of example
only, since they are influenced by additional factors, such as the
nature of the vaporizer).
[0067] It will be appreciated that while some devices may have just
two settings of the facility, other devices may have more settings;
furthermore some devices may support a continuous range of settings
between upper and lower limits. In general, the facility may be
operated by a user to control turbulence by selecting an
appropriate setting, such as by actuating a button or slider, or
touching a touch-sensitive input device. In this way, a user can
select a setting that provides them with the most satisfactory user
experience. In other cases, the facility might be alternatively (or
additionally) operated on an automatic basis. For example, the
device might detect that a particular cartridge or cartomizer has
been installed, and set the facility to provide the most
appropriate turbulence level for this cartridge.
[0068] There are various ways in which the facility may be
implemented. For example, in some cases the facility might support
movement of the airflow pathway such as to introduce or remove a
linear channel between the air inlet and the vaporizer. Other ways
of changing the turbulence level might be to use a (re)movable
airflow divider to divide a portion of the air pathway into two or
more channels; a variable aperture (or apertures) along the
pathway; or one or more structures that can be introduced into or
altered within the air pathway. Note that the facility might
utilise multiple different approaches for changing the level of
turbulence.
[0069] In some implementations, the facility is arranged to
maintain a substantially constant airflow through the air pathway
as the facility provides different levels of turbulence. For
example, the facility may use a smooth (circular) aperture to
reduce turbulence, or a more angled aperture, e.g. a star, to
increase turbulence. The overall size of each aperture may then be
configured such that the differently shaped apertures provide the
same resistance to draw (and hence overall airflow). In this way, a
user is able to adjust the particle size of the aerosol without
also changing other parameters of the device, such as resistance to
draw, which supports easier device management for a user.
[0070] In order to address various issues and advance the art, this
disclosure shows by way of illustration various embodiments in
which the claimed disclosure may be practiced. The advantages and
features of the disclosure are of a representative sample of
embodiments only, and are not exhaustive or exclusive. They are
presented only to assist in understanding and to teach the claimed
disclosure. It is to be understood that advantages, embodiments,
examples, functions, features, structures, 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 embodiments not presently claimed, but which may be claimed
in future.
* * * * *