U.S. patent application number 14/199365 was filed with the patent office on 2014-09-18 for electronic smoking article.
This patent application is currently assigned to Altria Client Services Inc.. The applicant listed for this patent is Altria Client Services Inc.. Invention is credited to Christopher S. Tucker.
Application Number | 20140261488 14/199365 |
Document ID | / |
Family ID | 50349991 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140261488 |
Kind Code |
A1 |
Tucker; Christopher S. |
September 18, 2014 |
ELECTRONIC SMOKING ARTICLE
Abstract
An electronic smoking article includes a first capillary aerosol
generator and a second capillary aerosol generator. The first
capillary aerosol generator produces an aerosol having a first
particle size distribution and the second capillary aerosol
generator produces an aerosol having a second particle size
distribution.
Inventors: |
Tucker; Christopher S.;
(Midlothian, VA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Altria Client Services Inc. |
Richmond |
VA |
US |
|
|
Assignee: |
Altria Client Services Inc.
Richmond
VA
|
Family ID: |
50349991 |
Appl. No.: |
14/199365 |
Filed: |
March 6, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61798010 |
Mar 15, 2013 |
|
|
|
Current U.S.
Class: |
131/328 ;
131/329 |
Current CPC
Class: |
A61M 15/0021 20140204;
A61M 11/042 20140204; A61M 15/0003 20140204; A24F 47/008 20130101;
A61M 11/001 20140204; A61M 2016/0018 20130101; A61M 2205/8206
20130101; A61M 2205/3368 20130101; A61M 15/06 20130101; A61M
2205/3653 20130101; A61M 2205/50 20130101 |
Class at
Publication: |
131/328 ;
131/329 |
International
Class: |
A24F 47/00 20060101
A24F047/00 |
Claims
1. An electronic smoking article comprising: a first capillary
aerosol generator which produces a first aerosol of a first liquid
material including flavor material; and a second capillary aerosol
generator which produces a second aerosol of a second liquid
material, the second liquid material including nicotine, wherein
the first aerosol has a first particle size distribution and the
second aerosol has a second particle size distribution.
2. The electronic smoking article of claim 1, wherein the first
capillary aerosol generator comprises: a first capillary tube
having a first capillary inlet and a first capillary outlet, the
first capillary inlet in communication with the first liquid
material; and a first heater operable to heat the first capillary
tube to a temperature sufficient to volatilize the first liquid
material contained within the first capillary tube.
3. The electronic smoking article of claim 2, wherein the second
capillary aerosol generator comprises: a second capillary tube
having a second capillary inlet and a second capillary outlet, the
second capillary inlet in communication with the second liquid
material; and a second heater operable to heat the second capillary
tube to a temperature sufficient to volatilize the second liquid
material contained within the second capillary tube.
4. The electronic smoking article of claim 3, wherein the first
liquid material and the second liquid material have different room
temperature viscosities.
5. The electronic smoking article of claim 3, wherein the first
liquid material comprises flavor material and the second liquid
material comprises nicotine.
6. The electronic smoking article of claim 3, wherein an internal
diameter of the first capillary tube is smaller than an internal
diameter of the second capillary tube.
7. The electronic smoking article of claim 3, further comprising: a
power supply operable to apply voltage across the first heater and
the second heater; a mixing chamber downstream of the first
capillary tube and the second capillary tube; and at least one air
inlet operable to deliver air into the mixing chamber during
drawing on the electronic smoking article.
8. The electronic smoking article of claim 6, wherein each of the
first capillary tube and the second capillary tube has an internal
diameter of about 0.05 to 0.4 mm and a length of about 5 mm to
about 72 mm or about 10 mm to 60 mm.
9. The electronic smoking article of claim 6, wherein each of the
first capillary tube and the second capillary tube comprise a
stainless steel tube or a non-metallic tube.
10. The electronic smoking article of claim 7, wherein the power
supply includes a battery.
11. The electronic smoking article of claim 10, wherein the first
heater is connected to the battery by two spaced apart electrical
leads and wherein the second heater is connected to the battery by
two spaced apart electrical leads.
12. The electronic smoking article of claim 10, wherein the first
heater and the second heater are connected in series.
13. The electronic smoking article of claim 7, further including
control circuitry operable to control supply of power from the
power supply to the first heater and the second heater.
14. The electronic smoking article of claim 13, wherein the control
circuitry further includes a heater activation light at an upstream
end of the electronic smoking article, the heater activation light
operable to light up when the first heater and the second heater
are activated.
15. The electronic smoking article of claim 3, further including a
first valve between a first pressurized liquid supply and the first
capillary inlet.
16. The electronic smoking article of claim 15, further including a
second valve between a second outlet of a second pressurized liquid
supply and the second capillary inlet.
17. The electronic smoking article of claim 16, wherein the first
valve and the second valve are electrically operated valves and the
electronic smoking article further includes a pressure switch, the
pressure switch operable to send a signal to open the first valve
and the second valve and to send a signal to the control circuitry
to supply power to the first heater and the second heater.
18. The electronic smoking article of claim 3, further including a
puff sensor operable to sense a draw on the electronic smoking
article.
19. The electronic smoking article of claim 7, wherein the
electronic smoking article includes a first section and a second
section and wherein the first section contains the first capillary
aerosol generator and the second capillary aerosol generator and
the second section contains the power supply and control circuitry
operable to control heating of the first and second heaters.
20. The electronic smoking article of claim 19, wherein the first
section is replaceable and the second section is reusable.
21. A method of forming an aerosol containing two particle size
distributions comprising: supplying a first liquid containing
flavor material to a first capillary tube; supplying a second
liquid containing nicotine to a second capillary tube;
simultaneously heating the first capillary tube and the second
capillary tube to a temperature sufficient to volatilize the first
liquid and the second liquid to form a first vapor and a second
vapor; mixing the first vapor with air to produce a first aerosol;
mixing the second vapor with air to produce a second aerosol; and
combining the first and second aerosols in a mixing chamber.
22. The method of claim 21, wherein the first aerosol comprises
particles ranging in size from about 0.4 micron to about 2
microns.
23. The method of claim 21, wherein the second aerosol comprises
particles ranging in size from about 0.5 micron to about 1
micron.
24. The method of claim 21, wherein the heating of the first
capillary tube and the heating of the second capillary tube occur
within a puff cycle at different times within the puff cycle.
25. The method of claim 21, wherein the heating of the first
capillary tube and the heating of the second capillary tube occur
within a puff cycle and achieve different temperatures within the
puff cycle.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority under 35 U.S.C.
.sctn.119(e) to U.S. provisional Application No. 61/798,010, filed
on Mar. 15, 2013, the entire content of which is incorporated
herein by reference thereto.
WORKING ENVIRONMENT
[0002] Many of the embodiments disclosed herein include electronic
smoking articles which include heated capillary aerosol generators.
The heated capillary volatilizes a liquid such as by way of the
teachings set forth in U.S. Pat. No. 5,743,251, which is
incorporated herein in its entirety by reference thereto.
SUMMARY OF SELECTED FEATURES
[0003] An electronic smoking article comprising a first capillary
aerosol generator which produces a first aerosol of a first liquid
material including flavor material and a second capillary aerosol
generator which produces a second aerosol of a second liquid
material, the second liquid material including nicotine. The first
aerosol has a first particle size distribution and the second
aerosol has a second particle size distribution.
[0004] A method of forming an aerosol containing two particle size
distributions comprises supplying a first liquid containing flavor
material to a first capillary tube, supplying a second liquid
containing nicotine to a second capillary tube, simultaneously
heating the first capillary tube and the second capillary tube to a
temperature sufficient to volatilize the first liquid and the
second liquid to form a first vapor and a second vapor, mixing the
first vapor with air to produce a first aerosol, mixing the second
vapor with air to produce a second aerosol, and combining the first
and second aerosols in a mixing chamber. The heating of the first
capillary tube and the heating of the second capillary tube can
occur within a puff cycle at different times within the puff cycle.
Moreover, the heating of the first capillary tube and the heating
of the second capillary tube occur within a puff cycle and achieve
different temperatures within the puff cycle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a side view of an electronic smoking article.
[0006] FIG. 2 is a cross-sectional view of the electronic smoking
article of FIG. 1.
[0007] FIG. 3 is an illustration of a capillary tube having a
constriction adjacent an outlet of the capillary tube.
[0008] FIG. 4 is a cross-sectional view of a second embodiment of
an electronic smoking article including two capillary aerosol
generators.
DETAILED DESCRIPTION
[0009] An electronic smoking article, such as an electronic
cigarette or an electronic cigar, is described herein which
produces an aerosol having two different particle size
distributions. A first particle size distribution is formed using a
first capillary aerosol generator having a first liquid supply
reservoir that contains liquid material. A second particle size
distribution is formed using a second capillary aerosol generator
having a second liquid supply reservoir that contains liquid
material. The first liquid material can include flavor material and
the second liquid material can include nicotine. The first liquid
supply reservoir and the second liquid supply reservoir can contain
liquids having different viscosities.
[0010] Advantageously, by providing an aerosol with two different
particle size distributions, the aerosol can be tailored to provide
desired flavor and/or therapeutic compositions. For example, the
flavor compounds can have a larger median particle size so as to be
deposited in the mouth and throat, while functional compounds, such
as nicotine or therapeutic compounds can be provided in smaller
particle sizes so as to deliver the particles deeper into the lower
respiratory tract.
[0011] As shown in FIG. 1, an electronic smoking article 60
comprises a replaceable cartridge (or first section) 70 and a
reusable fixture (or second section) 72, which are coupled together
at a threaded joint 74 or by other convenience such as a snug-fit,
snap-fit, detent, clamp and/or clasp.
[0012] The first section 70 can house a mouth-end insert 20, two
capillary tubes 18a, 18b, two heaters 19a, 19b to heat at least a
portion of each capillary tube 18a, 18b (which may comprise a
heatable portion 19a, 19b of the capillary tube 18a, 18b itself)
and two liquid supply reservoirs 14a, 14b. The second section 72
can house a power supply 12, control circuitry 11 and a puff sensor
16. A threaded portion of the section 72 can be connected to a
battery charger when not connected to the first section 70 for use
so as to charge the battery.
[0013] Preferably, the first section 70 and the second section 72
include an outer cylindrical housing 22 extending in a longitudinal
direction along the length of the electronic smoking article 60.
Preferably, the outer tube 6 is formed of a metal and is part of
the electrical circuit. In other embodiments, the outer tube 6 can
formed of any suitable material or combination of materials.
Examples of suitable materials include metals, alloys, plastics or
composite materials containing one or more of those materials, or
thermoplastics that are suitable for food or pharmaceutical
applications, for example polypropylene, polyetheretherketone
(PEEK), ceramic, and polyethylene. Preferably, the material is
light and non-brittle.
[0014] In one embodiment, the first section 70 is disposable and
the second section 72 is reusable. In another embodiment, both the
first section 70 and the second section 72 are disposable. The
sections 70, 72 can be attached by a threaded connection.
[0015] In the preferred embodiment, each liquid supply reservoir
14a, 14b is a tubular, elongate body that holds a predetermined
quantity of liquid material. Preferably, each liquid supply
reservoir 14a, 14b is pressurized such that the liquid material
therein is under constant pressure. As shown in FIG. 2, each liquid
supply reservoir 14a, 14b can include a pressurization arrangement
50a, 50b, such as an internal or external spring and plate
arrangement which constantly applies pressure to each liquid supply
reservoir 14a, 14b. For example, each liquid supply reservoir 14a,
14b can be compressible and positioned between two plates that are
connected by springs. Alternatively, each liquid supply reservoir
14a, 14b could be compressible and positioned between the outer
housing and a plate and the plate and outer housing could be
connected by a spring so that the plate applies pressure to each
liquid supply reservoir 14a, 14b.
[0016] Preferably, each liquid supply reservoir 14a, 14b has an
outlet 16a, 16b which is in fluid communication with a capillary
tube 18a, 18b. A valve 40a, 40b connects each outlet 16a, 16b to
the respective capillary tube 18a, 18b so as to prevent flow of
liquid material when the electronic smoking article 60 is not in
use. When each valve 40a, 40b is opened, each liquid supply
reservoir 14a, 14b can deliver a volume of liquid material to one
of the capillary tubes 18a, 18b. During delivery of liquid to the
capillary tubes 18a, 18b, the power supply 12 is activated and each
capillary tube 18a, 18b is heated to form a heated section wherein
the liquid material is volatilized. Upon discharge from the heated
capillary tubes 18a, 18b, two streams of volatilized material mix
with air that enters the electronic smoking article 60 via air
inlets 44, and form two aerosols which are combined in a mixing
chamber 46.
[0017] Preferably, each liquid supply reservoir 14a, 14b extends
longitudinally within the outer cylindrical housing 22 of the first
section 70. Moreover, each liquid supply reservoir 14a, 14b can
comprise a different liquid material which is volatilized when
heated and forms an aerosol. Each aerosol can have the same or
different particle size distributions. For example, the liquid
supply reservoir 14a can include flavor material, while the liquid
supply reservoir 14b can include a tobacco derived ingredient, such
as nicotine.
[0018] In the preferred embodiment, each capillary tube 18a, 18b
includes an inlet end 62a, 62b in fluid communication with the
outlet 16a, 16b of the liquid supply reservoir 14a, 14b, and an
outlet end 63a, 63b operable to expel volatilized liquid material
from each capillary tube 18a, 18b. In some embodiments, one or both
capillary tube 18a, 18b can include a constriction 101a (shown in
FIG. 3) at an outlet end 63a, 63b of the capillary tube 18a, 18b.
While not wishing to be bound by theory, it is believed that the
addition of a constriction at the outlet of the capillary tube,
which reduces the cross-sectional area of the outlet end, can
create sufficiently high shear forces to break up coarse droplets,
which can increase the conversion of the liquid material to small
particles.
[0019] Preferably, each capillary tube 18a, 18b has a different
internal diameter so as to aid in promoting formation of an aerosol
having a particular particle size distribution. For example, each
of the capillary tubes 18a, 18b can have an internal diameter of
0.01 to 10 mm, preferably 0.05 to 1 mm, and more preferably 0.05 to
0.4 mm. For example, the capillary tube 18a can have an internal
diameter of about 0.05 mm and the capillary tube 18b can have an
internal diameter of about 0.4 mm. Capillary tubes of smaller
diameter provide more efficient heat transfer to the fluid because,
with the shorter the distance to the center of the fluid, less
energy and time is required to vaporize the liquid.
[0020] Also preferably, each capillary tube 18a, 18b may have a
length of about 5 mm to about 72 mm, more preferably about 10 mm to
about 60 mm or about 20 mm to about 50 mm. For example, each
capillary tube 18a, 18b can be about 50 mm in length and arranged
such that a downstream, about 40 mm long portion of the capillary
tube 18a, 18b forms a coiled heated section and an upstream, about
10 mm long portion of the capillary tube 18a, 18b remains
relatively unheated when the heater 19a, 19b is activated.
[0021] In one embodiment, each capillary tube 18a, 18b is
substantially straight. In other embodiments, one or both capillary
tubes 18a, 18b are coiled and/or include one or more bends therein
to conserve space.
[0022] In the preferred embodiment, each capillary tube 18a, 18b is
formed of a conductive material, and thus acts as its own heater
19a, 19b by passing current through the tube. The capillary tubes
18a, 18b may be any electrically conductive material capable of
being resistively heated, while retaining the necessary structural
integrity at the operating temperatures experienced by the
capillary tubes 18a, 18b, and which is non-reactive with the liquid
material. Suitable materials for forming the capillary tubes 18a,
18b are selected from the group consisting of stainless steel,
copper, copper alloys, porous ceramic materials coated with film
resistive material, Inconel.RTM. available from Special Metals
Corporation, which is a nickel-chromium alloy, nichrome, which is
also a nickel-chromium alloy, and combinations thereof.
[0023] In one embodiment, each capillary tube 18a, 18b is a
stainless steel capillary tube 18a, 18b, a portion of which serves
as a heater 19a, 19b. The heater 19a, 19b is established between
electrical leads 26a, 26b and an electrical connection 110 adjacent
the outlet ends 63a, 63b of the capillary tubes 18a, 18b. Thus, a
direct or alternating current passes along a length of the
capillary tube 18a, 18b to form the heater 19a, 19b. The first and
second capillary tubes can be electrically connected in series such
that the first and second capillary tubes 18a, 18b are heated by
passing electrical current from the power source along the first
capillary tube, through the electrical connection interconnecting
the first and second capillary tubes, and alohg the second
capillary tube, such that the electrical current is effective to
heat the capillary tubes to a temperature sufficient to volatilize
liquid material contained therein as in U.S. Pat. No. 6,715,487
which is incorporated herein in its entirety by reference thereto.
In an alternative embodiment, the capillary tubes 18a, 18b can be
connected in parallel.
[0024] Thus, the stainless steel capillary tube 18a, 18b is heated
by resistance heating. The stainless steel capillary tube 18a, 18b
is preferably circular in cross section. The capillary tube 18a,
18b may be of tubing suitable for use as a hypodermic needle of
various gauges. For example, the capillary tube 18a, 18b may
comprise a 32 gauge needle has an internal diameter of 0.11 mm and
a 26 gauge needle has an internal diameter of 0.26 mm.
[0025] In another embodiment, the capillary tube 18a, 18b may be a
non-metallic tube such as, for example, a glass tube. In such an
embodiment, the heater 19a, 19b is formed of a conductive material
capable of being resistively heated, such as, for example,
stainless steel, nichrome or platinum wire, arranged along the
glass tube. When the heater arranged along the glass tube is
heated, liquid material in the capillary tube 18a, 18b is heated to
a temperature sufficient to at least partially volatilize liquid
material in the capillary tube 18a, 18b. In other embodiments, one
capillary tube 18a can be stainless steel and one capillary tube
18b can be a glass tube.
[0026] Preferably, as shown in FIG. 2, that electrical leads 26a,
26b and the electrical connection 110 are bonded to the metallic
capillary tubes 18a, 18b. In the preferred embodiment, the
electrical leads 26a, 26b are brazed to the capillary tubes 18a,
18b. Preferably, one electrical lead 26a is brazed to a first,
upstream portion of the first capillary tube 18a and a second
electrical lead 26b is brazed to an upstream portion of the second
capillary tube 18b as shown in FIG. 2.
[0027] In use, once each capillary tube 18a, 18b is heated, the
liquid material contained within a heated portion of each capillary
tube 18a, 18b is volatilized and ejected out of the outlet 63a, 63b
where it expands and mixes with air from one or more air inlets 44
and forms an aerosol in a mixing chamber 46.
[0028] Preferably, the electronic smoking article 60 includes at
least one air inlet 44 operable to deliver air to the mixing
chamber 46. Preferably, the air inlets 44 to the mixing chamber 46
are arranged downstream of the capillary tubes 18a, 18b so as to
minimize drawing air along the capillary tube and thereby avoid
cooling of the capillary tubes 18a, 18b during heating cycles. In
use, the volatilized material expands out of each capillary tubes
18a, 18b and into the mixing chamber 46 where it can mix with air
to form an aerosol which is then drawn through the mouth-end insert
20. In the preferred embodiment, the at least one air inlet 44
includes one or two air inlets. Alternatively, there may be three,
four, five or more air inlets 44. Altering the size and number of
air inlets 44 can also aid in establishing the resistance to draw
of the electronic smoking article 60.
[0029] In the preferred embodiment, each liquid supply reservoir
14a, 14b may include an electrically operated or a mechanically
operated valve 40a, 40b, shown in FIG. 2. Each valve 40a, 40b is
operable to maintain the liquid material within the liquid supply,
but opens when the electronic smoking article 60 is activated.
Preferably, the electronic smoking article is manually activated by
pressing a button (pressure switch) 100 (shown in FIG. 1), which
opens the valves 40a, 40b and simultaneously activates the heaters
19a, 19b. In other embodiments, the valves 40a, 40b and the heaters
19a, 19b can be puff activated, such that when a smoker draws upon
the electronic smoking article 60, the puff sensor 16 communicates
with the control circuitry 11 to activate the heaters 19a, 19b and
open the valves 40a, 40b.
[0030] Preferably, if the button 100 is used to manually activate
the electronic smoking article 60, the valve 40a, 40b opens when a
critical, minimum pressure is reached so as to avoid inadvertent
dispensing of liquid material from the liquid supply reservoirs
14a, 14b or activating the heaters 19a, 19b. Preferably, the
pressure required to press the button 100 is high enough such that
accidental heating is avoided. Such arrangement avoids activation
of the heaters 19a, 19b in the absence of liquid being pumped
through the capillary tube.
[0031] Advantageously, the use of valves 40a, 40b also aids in
limiting the amount of liquid that is drawn back from each
capillary tube upon release of pressure upon the liquid supply
reservoir 14 (and/or the switch 44). Withdrawal of liquid from the
capillary tube at conclusion of a puff (or activation) is desirous.
The presence of residual liquid in the capillary tube at the
initiation of a new puff cycle can lead to undesirable sputtering
of liquid from the heated capillary tube at the beginning of
activation. The valves 40a, 40b can be configured to allow a
desired, limited amount of drawback to occur, such that drawback of
liquid occurs without air being drawn into the liquid supply
reservoirs 14a, 14b.
[0032] Advantageously, each capillary tube 18a, 18b is purged once
a smoker has stopped drawing on the electronic smoking article 60
or has stopped pushing the button 100 because any liquid remaining
in the tube is expelled (volatilized) during heating.
[0033] In the preferred embodiment, the power supply 12 includes a
battery arranged in the electronic smoking article 60. The heaters
19a, 19b can be connected to the battery by the electrical leads
26a, 26b. The power supply 12 is operable to apply voltage across
the heaters 19a, 19b associated with the capillary tubes 18a, 18b
and volatilize liquid material contained therein according to a
power cycle of either a predetermined time period, such as a 2 to
10 second period, or for so long as pressure is applied to the
button (pressure switch) 100. The control circuitry 11 can be
programmable and can include a microprocessor programmed to carry
out functions such as heating the capillary tubes and/or operating
the valves. In other embodiments, the control circuitry 11 can
include an application specific integrated circuit (ASIC).
[0034] Preferably, the electrical contacts or connection between
the heaters 19a, 19b and the electrical leads 26a, 26b are highly
conductive and temperature resistant while the heatable portions
19a, 19b of the capillary tubes 18a, 18b are highly resistive so
that heat generation occurs primarily along the heaters 19a, 19b
and not at the contacts.
[0035] The battery can be a Lithium-ion battery or one of its
variants, for example a Lithium-ion polymer battery. Alternatively,
the battery may be a Nickel-metal hydride battery, a Nickel cadmium
battery, a Lithium-manganese battery, a Lithium-cobalt battery or a
fuel cell. In that case, preferably, the electronic smoking article
60 is usable by a smoker until the energy in the power supply is
depleted. Alternatively, the power supply 12 may be rechargeable
and include circuitry allowing the battery to be chargeable by an
external charging device. In that case, preferably the circuitry,
when charged, provides power for a pre-determined number of puffs,
after which the circuitry must be re-connected to an external
charging device.
[0036] Preferably, the electronic smoking article 60 also includes
control circuitry which can be on a printed circuit board 11. Once
the button 100 (pressure switch) is pressed, the power supply 12 is
activated and supplies power to the heaters 19a, 19b. The control
circuitry 11 can also include a heater activation light 27 operable
to glow when the heaters 19a, 19b are activated. Preferably, the
heater activation light 27 comprises at least one LED and is at an
upstream end 5 (shown in FIG. 1) of the electronic smoking article
60 so that the heater activation light 27 takes on the appearance
of a burning coal during a puff. Moreover, the heater activation
light 27 can be arranged to be visible to the smoker. In addition,
the heater activation light 27 can be utilized for smoking article
system diagnostics. The light 27 can also be configured such that
the smoker can activate and/or deactivate the light 27 when
desired, such that the light 27 would not activate during smoking
if desired.
[0037] Preferably, when activated, the heaters 19a, 19b heat a
portion of the capillary tubes 18a, 18b for less than about 10
seconds, more preferably less than about 7 seconds. Thus, the power
cycle (or maximum puff length) can range in period from about 2
seconds to about 10 seconds (e.g., about 3 seconds to about 9
seconds, about 4 seconds to about 8 seconds or about 5 seconds to
about 7 seconds).
[0038] In the preferred embodiment, the liquid supply reservoirs
14a, 14b each include a liquid material which has a boiling point
suitable for use in the electronic smoking article 60. If the
boiling point is too high, the heaters 19a, 19b will not be able to
vaporize liquid in the capillary tubes 18a, 18b. However, if the
boiling point is too low, the liquid may vaporize without the
heaters 19a, 19b being activated.
[0039] Preferably, the liquid supply reservoirs 14a, 14b each
contain a different liquid material having different viscosities.
The first liquid supply reservoir 14a can include at least one
flavor material. The second liquid supply reservoir 14b can include
at least one tobacco derived ingredient, such as nicotine.
Preferably, the liquid material in the second liquid supply
reservoir 14b is more viscous at room temperature than the liquid
material in the first liquid supply reservoir 14a. Moreover, the
capillary tube 18b, associated with the second liquid supply
reservoir 14b, preferably has a larger internal diameter than the
capillary tube 18a associated with the first liquid supply
reservoir 14a. Accordingly, the first capillary tube 18a produces
aerosol having particles ranging in size from about 0.4 micron to
about 2 microns depending on the flavor material included in the
liquid supply reservoir 14a and the viscosity thereof. The second
capillary tube 18b produces an aerosol having particles ranging in
size from about 0.5 micron to about 1 micron. Advantageously, the
electronic smoking article can be configured to form a first
aerosol having larger particles for delivery to the mouth and a
second aerosol having smaller particles for delivery to the lower
respiratory tract if desired.
[0040] The second liquid supply reservoir 14b can include nicotine.
The first liquid supply reservoir 14a can include flavor material,
a non-tobacco material and/or may be nicotine-free. For example,
the liquid material in the first liquid supply reservoir 14a may
include water, solvents, ethanol, plant extracts and natural or
artificial flavors. Preferably, the liquid in each of the first
liquid supply reservoir 14a and the second liquid supply reservoir
14b can include an aerosol former. Examples of suitable aerosol
formers are glycerine and propylene glycol.
[0041] As shown in FIG. 2 the electronic smoking article 60 further
includes a mouth-end insert 20 having at least two off-axis,
preferably diverging outlets 21. Preferably, the mouth-end insert
20 is in fluid communication with the mixing chamber 46 and
includes at least two diverging outlets 21. (e.g, 3, 4, 5, or
preferably 6 to 10 outlets or more). Preferably, the outlets 21 of
the mouth-end insert 20 are located at ends of off-axis passages 23
and are angled outwardly in relation to the longitudinal direction
of the electronic smoking article 60 (i.e., divergently). As used
herein, the term "off-axis" denotes at an angle to the longitudinal
direction of the electronic smoking article 60. Also preferably,
the mouth-end insert (or flow guide) 20 includes four outlets
uniformly distributed around the mouth-end insert 20 so as to
substantially uniformly distribute aerosol in a smoker's mouth
during use. Thus, as the aerosol passes into a smoker's mouth, the
aerosol enters the mouth and moves in different directions so as to
provide a full mouth feel as compared to electronic smoking
articles having an on-axis single orifice which directs the aerosol
to a single location in a smoker's mouth.
[0042] In addition, the outlets 21 and off-axis passages 23 are
arranged such that droplets of unaerosolized liquid material
carried in the aerosol impact interior surfaces 25 of the mouth-end
insert 20 and/or interior surfaces of the off-axis passages 23 such
that the droplets are removed or broken apart. In the preferred
embodiment, the outlets 21 of the mouth-end insert 20 are located
at the ends of the off-axis passages 23 and are angled at 5 to
60.degree. with respect to the central longitudinal axis of the
electronic smoking article 60 so as to more completely distribute
aerosol throughout a mouth of a smoker during use and to remove
droplets.
[0043] Preferably, each outlet 21 has a diameter of about 0.015
inch to about 0.090 inch (e.g., about 0.020 inch to about 0.040
inch or about 0.028 inch to about 0.038 inch). The size of the
outlets 21 and off-axis passages 23 along with the number of
outlets 21 can be selected to adjust the resistance to draw (RTD)
of the electronic smoking article 60, if desired.
[0044] Preferably, the mouth-end insert 20 is affixed within the
outer cylindrical housing 22 of the cartridge 70.
[0045] In a preferred embodiment, the electronic smoking article 60
is about the same size as a conventional cigarette. In some
embodiments, the electronic smoking article 60 can be about 80 mm
to about 110 mm long, preferably about 80 mm to about 100 mm long
and about 7 mm to about 8 mm in diameter. For example, in an
embodiment, the electronic smoking article is about 84 mm long and
has a diameter of about 7.8 mm.
[0046] The outer cylindrical housing 22 of the electronic smoking
article 60 may be formed of any suitable material or combination of
materials. Preferably, the outer cylindrical housing 22 is formed
of metal. Examples of suitable materials include metals, alloys,
plastics or composite materials containing one or more of those
materials, or thermoplastics that are suitable for food or
pharmaceutical applications, for example polypropylene,
polyetheretherketone (PEEK), ceramic, low density polyethylene
(LDPE) and high density polyethylene (HDPE). Preferably, the
material is light and non-brittle. The outer cylindrical housing 22
can be any suitable color and/or can include graphics or other
indicia printed thereon.
[0047] When the word "about" is used in this specification in
connection with a numerical value, it is intended that the
associated numerical value include a tolerance of .+-.10% around
the stated numerical value. Moreover, when reference is made to
percentages in this specification, it is intended that those
percentages are based on weight, i.e., weight percentages.
[0048] Moreover, when the words "generally" and "substantially" are
used in connection with geometric shapes, it is intended that
precision of the geometric shape is not required but that latitude
for the shape is within the scope of the disclosure. When used with
geometric terms, the words "generally" and "substantially" are
intended to encompass not only features which meet the strict
definitions but also features which fairly approximate the strict
definitions.
[0049] It will now be apparent that a new, improved, and nonobvious
electronic smoking article has been described in this specification
with sufficient particularity as to be understood by one of
ordinary skill in the art. Moreover, it will be apparent to those
skilled in the art that numerous modifications, variations,
substitutions, and equivalents exist for features of the electronic
smoking article which do not materially depart from the spirit and
scope of the invention. Accordingly, it is expressly intended that
all such modifications, variations, substitutions, and equivalents
which fall within the spirit and scope of the invention as defined
by the appended claims shall be embraced by the appended
claims.
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