U.S. patent application number 14/404178 was filed with the patent office on 2015-06-18 for filter for a smoking article.
The applicant listed for this patent is British American Tabacco (Investments) Limited. Invention is credited to Andrew Davis.
Application Number | 20150164133 14/404178 |
Document ID | / |
Family ID | 46546173 |
Filed Date | 2015-06-18 |
United States Patent
Application |
20150164133 |
Kind Code |
A1 |
Davis; Andrew |
June 18, 2015 |
Filter for a Smoking Article
Abstract
The invention relates to a filter (1) for a smoking article, a
method of production thereof, a smoking article and a device for
inserting a first fibrous filter material (3) into a second fibrous
filter material (4) to form a filter for a smoking article.
Particularly but not exclusively the invention relates to a smoking
article filter segment including a region of first fibrous filter
material (3) disposed within a region of second fibrous filter
material (4) and a method of production thereof. The first fibrous
filter material (3) in some embodiments comprises greater than 5%
by volume of the total filter segment volume and in some
embodiments the first fibrous material comprises PLA fibres and the
second fibrous filter material comprises CA fibres.
Inventors: |
Davis; Andrew; (London,
GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
British American Tabacco (Investments) Limited |
London, LO |
|
GB |
|
|
Family ID: |
46546173 |
Appl. No.: |
14/404178 |
Filed: |
May 24, 2013 |
PCT Filed: |
May 24, 2013 |
PCT NO: |
PCT/GB2013/051392 |
371 Date: |
January 22, 2015 |
Current U.S.
Class: |
131/332 ;
493/39 |
Current CPC
Class: |
A24D 3/025 20130101;
A24D 3/04 20130101; A24D 3/063 20130101; A24D 3/0229 20130101; A24D
3/0212 20130101 |
International
Class: |
A24D 3/06 20060101
A24D003/06; A24D 3/02 20060101 A24D003/02 |
Foreign Application Data
Date |
Code |
Application Number |
May 30, 2012 |
GB |
1209589.9 |
Claims
1. A filter segment for a smoking article, the filter segment
comprising a region of first fibrous filter material disposed at
least substantially within a region of second fibrous filter
material, wherein the first fibrous filter material comprises
greater than 5% by volume of the total filter segment volume, the
second fibrous filter material is a plasticised filter material and
the first fibrous filter material is a non-plasticised filter
material.
2. A filter segment according to claim 1, wherein the first fibrous
filter material is disposed in a plurality of regions of the filter
segment.
3. A filter segment according to claim 2, wherein the plurality of
regions can each comprise greater than 3% of the total filter
segment volume.
4. A filter segment according to claim 1, wherein the first and
second fibrous filter materials comprise crimped fibres.
5. A filter segment according to claim 1, wherein the first fibrous
filter material comprises polylactide (PLA) fibres and/or the
second fibrous filter material comprises cellulose acetate
fibres.
6. A filter segment according to claim 1, wherein the first fibrous
filter material comprises from 5 to 60% by volume of the total
filter segment volume.
7. A filter segment according to claim 1, wherein the first fibrous
filter material comprises from 10 to 60% by volume of the total
filter segment volume.
8. A filter segment according to claim 1, wherein the first fibrous
filter material comprises from 200 to 10,000 fibres having a denier
from 2 to 10 denier per filament.
9. A filter segment according to claim 1, wherein the region of
first fibrous filter material comprises a region extending
longitudinally through the region of second fibrous filter
material.
10. A filter segment for a smoking article, the filter segment
comprising a region of first fibrous material disposed at least
substantially within a region of second fibrous material, wherein
the first fibrous material comprises polylactide (PLA) fibres.
11. A filter segment according to claim 10, wherein the second
fibrous material comprises cellulose acetate (CA) fibres.
12. A smoking article comprising a filter segment according to
claim 1.
13. A method of producing a filter segment for a smoking article,
the method comprising: feeding a supply of a first fibrous filter
material into a second fibrous filter material to form a filter
segment, controlling the delivery speed of the first fibrous filter
material into the second fibrous filter material to meter the first
fibrous material into the second fibrous filter material; forming a
region of first fibrous filter material disposed substantially
within a region of second fibrous filter material, wherein the
first fibrous filter material comprises greater than 5% by volume
of the total filter segment volume, the second fibrous filter
material is a plasticized filter material and the first fibrous
filter material is a non-plasticized filter material.
23. The method of producing a filter segment for a smoking article
of claim 13 wherein the step of feeding a supply of a first fibrous
filter material into the second fibrous filter material includes
adjusting a terminating end of needle within a tongue into which
the second fibrous material flows.
14. A method according to claim 13, further comprising applying a
plasticiser to said second fibrous filter material prior to feeding
the supply of the first fibrous material into the second fibrous
filter material.
15. A method according to claim 13, further comprising crimping
said first and second fibrous filter materials prior to feeding the
supply of the first fibrous material into the second fibrous filter
material.
16. A method according to claim 13, further comprising compressing
said second fibrous filter material to form a filter rod and
feeding the supply of the first fibrous filter material into the
second fibrous filter material while compressing the second fibrous
filter material to form the filter rod.
17. A method according to claim 13, wherein the first fibrous
filter material is fed into the second fibrous filter material in a
tongue section of a filter making apparatus.
18. A method according to claim 13, wherein the first fibrous
filter material comprises a thread of first fibrous filter
material.
19. A method of producing a filter for a smoking article, the
method comprising: generating a fluid stream; and transferring a
first fibrous material along a transfer path through the fluid
stream, and then into a flow of a second fibrous filter
material.
20. A method according to claim 19, wherein said fluid stream is
generated using air pressure.
21. A method according to claim 19, wherein the first fibrous
filter material is transferred into the flow of the second fibrous
filter material in a tongue or stuffer jet section of a filter
making apparatus.
22. A device for inserting a first fibrous filter material into a
second fibrous filter material to form a filter for a smoking
article, the device comprising a pressure generator to generate a
fluid stream, wherein said first fibrous material is transferred
through said fluid stream generated by said pressure generator
along a transfer path and then into a flow of said second fibrous
filter material.
Description
TECHNICAL FIELD
[0001] The invention relates to a filter for a smoking article, a
method of production thereof, a smoking article and a device for
inserting a first fibrous filter material into a second fibrous
filter material to form a filter for a smoking article.
Particularly but not exclusively the invention relates to a filter
for a smoking article including a region of first fibrous filter
material disposed at least substantially within a region of second
fibrous filter material, a smoking article including such a filter
and a method and device for the production thereof.
BACKGROUND
[0002] It is known to use cellulose acetate fibres, plasticised
with an additive such as triacetin, in cigarette filters. It is
also known to use certain other fibrous materials, for instance
cotton or paper based materials, as an alternative to cellulose
acetate in cigarette filters.
SUMMARY
[0003] In accordance with embodiments of the invention, there is
provided a filter segment for a smoking article, the filter segment
comprising a region of first fibrous filter material disposed at
least substantially within a region of second fibrous filter
material, wherein the first fibrous filter material comprises
greater than 5% by volume of the total filter segment volume.
[0004] The first fibrous filter material can be disposed in a
plurality of regions of the filter segment. The plurality of
regions can each comprise greater than 3% of the total filter
segment volume.
[0005] The second fibrous filter material can be a plasticised
filter material and the first fibrous filter material can be a
non-plasticised filter material.
[0006] The first and second fibrous filter materials can comprise
crimped fibres.
[0007] The first fibrous filter material can comprise polylactide
(PLA) fibres and/or the second fibrous filter material can comprise
cellulose acetate fibres.
[0008] The first fibrous filter material can comprise from 5 to 60%
by volume of the total filter segment volume.
[0009] The first fibrous filter material can comprise from 10 to
20% by volume of the total filter segment volume.
[0010] The first fibrous filter material can comprise from 200 to
10,000 fibres having a denier from 2 to 10 denier per filament.
[0011] The region of first fibrous filter material can comprise a
region extending longitudinally through the region of second
fibrous filter material.
[0012] In accordance with embodiments of the invention, there is
also provided a filter segment for a smoking article, the filter
segment comprising a region of first fibrous material disposed at
least substantially within a region of second fibrous material,
wherein the first fibrous material comprises polylactide (PLA)
fibres.
[0013] The second fibrous material can comprise cellulose acetate
(CA) fibres.
[0014] In accordance with embodiments of the invention, there is
also provided a smoking article comprising a filter segment as set
out above.
[0015] In accordance with embodiments of the invention, there is
further provided a method of producing a filter segment for a
smoking article, the method comprising feeding a supply of a first
fibrous filter material into a second fibrous filter material to
form a filter segment as set out above.
[0016] The method can further comprise applying a plasticiser to
said second fibrous filter material prior to feeding the supply of
the first fibrous material into the second fibrous filter
material.
[0017] The method can further comprise crimping said first and
second fibrous filter materials prior to feeding the supply of the
first fibrous material into the second fibrous filter material.
[0018] The method can further comprise compressing said second
fibrous filter material to form a filter rod and feeding the supply
of the first fibrous filter material into the second fibrous filter
material while compressing the second fibrous filter material to
form the filter rod.
[0019] The first fibrous filter material can be fed into the second
filter material in a tongue section of a filter making apparatus.
The first fibrous filter material can comprise a thread of first
fibrous filter material.
[0020] In accordance with embodiments of the invention, there is
further provided a method of producing a filter for a smoking
article, the method comprising generating a fluid stream and
transferring a first fibrous material along a transfer path into a
flow of a second fibrous filter material using the fluid
stream.
[0021] The fluid stream can be generated using air pressure.
[0022] The first fibrous filter material can be transferred into
the flow of the second fibrous filter material in a tongue or
stuffer jet section of a filter making apparatus.
[0023] In accordance with embodiments of the invention, there is
further provided a device for inserting a first fibrous filter
material into a second fibrous filter material to form a filter for
a smoking article, the device comprising a pressure generator to
generate a fluid stream for carrying said first fibrous material
along a transfer path into a flow of said second fibrous filter
material.
[0024] In accordance with embodiments of the invention, there is
further provided a filter for a smoking article, as herein
described with reference to the accompanying drawings.
[0025] In accordance with embodiments of the invention, there is
further provided a smoking article as herein described with
reference to the accompanying drawings.
[0026] In accordance with embodiments of the invention, there is
further provided a fibrous material insertion device as herein
described with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Embodiments of the invention will now be described, by way
of example only, with reference to the accompanying drawings, in
which:
[0028] FIGS. 1(a) to 1(e) are schematic illustrations of smoking
articles including filter segments according to embodiments of the
invention;
[0029] FIG. 2 is a schematic illustration of a first device for
inserting a first fibrous filter material into a second fibrous
filter material to produce a filter segment such as those of the
smoking articles illustrated in FIGS. 1(a) to 1(d);
[0030] FIG. 3 is a schematic side view of a section of the device
of FIG. 2;
[0031] FIG. 4 is a schematic rear view of a section of the device
of FIG. 2;
[0032] FIG. 5 is a schematic illustration of a second device for
inserting a fibrous filter material into a second fibrous filter
material to produce a filter segment such as those of the smoking
articles illustrated in FIGS. 1(a) to 1(d);
[0033] FIG. 6 is a schematic side view of a section of the device
of FIG. 5;
[0034] FIG. 7 is a schematic rear view of a section of the device
of FIG. 5;
[0035] FIG. 8 is a schematic illustration of a third device
according to an embodiment of the invention for inserting a first
fibrous filter material into a second fibrous filter material to
produce a filter segment such as that of the smoking article
illustrated in FIG. 1(a);
[0036] FIG. 9 is a cross sectional schematic view of the device of
FIG. 8;
[0037] FIG. 10 is a cross sectional view of the venture device
shown in FIGS. 8 and 9;
[0038] FIG. 11 is a schematic illustration showing the operation of
the venturi device of FIGS. 8, 9 and 10;
[0039] FIG. 12 is a cross sectional schematic view of a fourth
device according to a further embodiment of the invention for
inserting a first fibrous filter material into a second fibrous
filter material to produce a filter segment such as that of the
smoking article illustrated in FIG. 1(a);
[0040] FIG. 13 is a schematic illustration of a fifth device
according to a further embodiment of the invention for inserting a
first fibrous filter material into a second fibrous filter material
to produce a filter segment such as those of the smoking articles
illustrated in FIGS. 1(a) to 1(d); and
[0041] FIG. 14 is a schematic illustration of a sixth device
according to a further embodiment of the invention for inserting a
first fibrous filter material into a second fibrous filter material
to produce a filter segment such as that illustrated in FIG.
1(e).
DETAILED DESCRIPTION
[0042] FIGS. 1(a) to 1(e) are schematic illustrations of smoking
articles including filter segments according to embodiments of the
invention.
[0043] As used herein, the term "smoking article" includes
smokeable products such as cigarettes, cigars and cigarillos
whether based on tobacco, tobacco derivatives, expanded tobacco,
reconstituted tobacco or tobacco substitutes and also heat-not-burn
products.
[0044] Referring to FIG. 1(a), a first smoking article 1 includes a
filter segment 2 having a region of first fibrous filter material 3
disposed substantially within a region of second fibrous filter
material 4. In the first smoking article 1, the filter segment 2
forms a mono filter having an overall cylindrical shape, with the
first fibrous filter material 3 disposed within a substantially
cylindrically shaped core region of the second fibrous filter
material 4, which forms an outer, hollow cylindrically shaped
region of the filter segment 2. The first fibrous filter material 3
accordingly extends axially through the length second fibrous
filter material 4, being in the present example exposed only at
each end of the mono filter.
[0045] The filter segment 2 of the first smoking article 1 is
wrapped in a plug wrap material 5 and connected to a tobacco rod 6
using a tipping material 7 to form the first smoking article 1, in
the present example a cigarette.
[0046] Referring to FIG. 1(b), a second smoking article 11 includes
a filter segment 12 having first and second regions of a first
fibrous filter material 13a, 13b disposed substantially within a
region of second fibrous filter material 14. In the second smoking
article 11, the filter segment 12 forms a mono filter having an
overall cylindrical shape, with the first fibrous filter material
13a, 13b disposed within first and second regions of the second
fibrous filter material 14. The first and second regions extend
longitudinally through the length of the second fibrous filter
material 14, being in the present example exposed from the second
fibrous filter material 14 only at each end of the mono filter. The
first and second regions of first fibrous filter material 13a, 13b
are substantially cylindrical in shape. In the present example, the
first and second regions of first fibrous filter material 13a, 13b
are diametrically spaced apart from each other and from the outer
longitudinal periphery of the second fibrous filter material
14.
[0047] The filter segment 12 of the second smoking article 11 is
wrapped in a plug wrap material 15 and connected to a tobacco rod
16 using a tipping material 17 to form the second smoking article
11, in the present example a cigarette.
[0048] Referring to FIG. 1(c), a third smoking article 21 includes
a filter segment 22 having a plurality of regions of first fibrous
filter material 23a-23d disposed substantially within a second
fibrous filter material 24. In the third smoking article 21, the
filter segment 22 forms a mono filter having an overall cylindrical
shape, with the first fibrous filter material 23a-23d disposed
within first to fourth regions. Each of the four regions of first
fibrous filter material 23a-23d extends longitudinally through the
length second fibrous filter material 24, being in the present
example exposed from the second fibrous filter material 24 only at
each end of the mono filter. The regions of first fibrous filter
material 23a-23d are substantially cylindrical in shape. In the
present example, the regions of first fibrous filter material
23a-23d are annularly disposed within the second filter material 24
and spaced at 90.degree. from each other and from the outer
longitudinal periphery of the second fibrous filter material
24.
[0049] The filter segment 22 of the third smoking article 21 is
wrapped in a plug wrap material 25 and connected to a tobacco rod
26 using a tipping material 27 to form the third smoking article
21, in the present case a cigarette.
[0050] Referring to FIG. 1(d), a fourth smoking article 31 includes
a filter segment 32 having a plurality of regions of first fibrous
filter material 33a-33e disposed substantially within a region of
second fibrous filter material 34. In the example of FIG. 1(d), the
filter segment 32 forms a mono filter having an overall cylindrical
shape, with the first 10o fibrous filter material 33a-23e disposed
within first to fifth regions. Each of the five regions of first
fibrous filter material 33a-33e extends longitudinally through the
length of the second fibrous filter material 34, being in the
present example exposed from the second fibrous filter material 34
only at each end of the mono filter. The regions of first fibrous
filter material 33a-33e are substantially cylindrical in shape. In
the present example, the first to fourth regions of first fibrous
filter material 33a-33d are annularly disposed within the second
filter material 34 and spaced at 90.degree. from each other and
from the outer longitudinal periphery of the second fibrous filter
material 34. The fifth region of first fibrous filter material 33e
is disposed within a substantially cylindrically shaped core of the
second fibrous filter material 34.
[0051] The filter segment 32 is wrapped in a plug wrap material 35
and connected to a tobacco rod 36 using a tipping material 37 to
form the third smoking article 31, in the present case a
cigarette.
[0052] Referring to FIG. 1(e), a fifth smoking article 161 includes
a filter segment 162 having a plurality of regions of first fibrous
filter material 16a-163b disposed substantially within a region of
second fibrous filter material 164. In the example of FIG. 1(e),
the filter segment 162 forms a mono filter having an overall
cylindrical shape, with the first fibrous filter material 163a-163b
disposed within first and second regions. Each of the first and
second regions of first fibrous filter material 163a-163b forms an
elongate sector of the cylindrical filter, and extends
longitudinally through the length of the second fibrous filter
material 164, being in the present example exposed from the second
fibrous filter material 164 at each end of the mono filter and
along the length of first and second outer portions 165a, 165b of
the longitudinal surface of the cylindrical filter segment 162.
[0053] The regions of first fibrous filter material 163a-163b have
the substantial shape of elongate sectors in the present example.
Also, the first and second regions of first fibrous filter material
163a-163b are disposed within the second filter material 164 spaced
at 180.degree. from each other. However, alternatively only one
region of first fibrous filter material 163 can be used, or three
or more regions of first fibrous filter material 163 can be used,
spaced evenly or unevenly around the filter segment 162. Also, the
shape of the regions of first fibrous filter material, whether one,
two, three or more regions, is not limited to an elongate sector,
and could be shaped substantially to have the form of an elongate
quadrilateral, such as a rectangle and/or oblong.
[0054] The filter segment 162 is wrapped in a plug wrap material
166 and connected to a tobacco rod 167 using a tipping material 168
to form the fifth smoking article 161, in the present case a
cigarette.
[0055] In the first to fifth smoking articles 1, 11, 21, 31, 161,
the first fibrous filter material 3, 13, 23, 33, 163 comprises a
non-plasticised filter material, in the present case polylactide
(also referred to as poly(lactic acid) or PLA) fibres. Such fibres
are commercially available, for instance from companies such as
Natureworks LLC in the US or Mitsui Chemical in Japan. Suitable
fibres can be formed in processes such as electrospinning, as would
be known to those skilled in the art. The second fibrous filter
material 4, 14, 24, 34, 164 comprises a plasticised filter
material, in the present case cellulose acetate (hereinafter `CA`)
fibres plasticised using triacetin (also referred to as glycerin
triacetate).
[0056] Use of both the first and the second fibrous filter
materials in a single filter segment can enable the smoking article
filter to benefit from properties of both materials. For instance,
the first and second filter materials may each have greater
selectivity in the filtration of certain smoke constituents than
the other material. One or other of the first and second filter
materials may be cheaper to produce or comprise a more sustainable
base material than the other filter material. For example, PLA is
generally considered to be a more sustainable filter material than
CA, although plasticised CA can have a greater filtration
selectivity to certain smoke constituents than PLA, for instance
phenols.
[0057] A limitation of PLA fibres and other non-cellulose acetate
based fibre materials can be that the fibres are relatively soft
and that certain CA filter plasticisers such as triacetin,
polyethylene glycol (PEG) and triethyl citrate (TEC), usually used
to increase the firmness of CA filters, are not sufficiently
effective at increasing the firmness of the non-cellulose acetate
material or mixtures of the non-cellulose acetate material with CA.
Accordingly, such filters may not be provided with an appropriate
rigidity and/or hardness for use in/as smoking article filters. The
filter segment structures provided in the first to fourth smoking
articles 1, 11, 21, 31, 161 of FIGS. 1(a) to 1(e) and other
embodiments of the invention can overcome such limitations by
enabling a first filter material such as PLA fibres to be held
substantially within the structure of a second filter material such
as CA fibres. The second filter material such as CA fibres can, for
instance, be plasticised to provide an appropriate rigidity and/or
hardness to the overall filter segment 2, 12, 22, 32, 162.
[0058] Other suitable materials for the first fibrous filter
material include paper or paper-based materials, polyvinyl alcohol
(PVOH) or PVOH based materials, starch-based materials,
reconstituted tobacco materials, extruded materials or other
fibrous filter materials, for instance those which cannot be
readily plasticised by a cellulose acetate plasticiser (although
the invention is not limited to the use of such materials).
[0059] Other suitable materials for the second fibrous filter
material include paper or paper-based materials, polyvinyl alcohol
(PVOH) or PVOH based materials, starch-based materials,
reconstituted tobacco materials, extruded materials or other
fibrous filter materials.
[0060] The first and/or second fibrous filter material can be
coloured and/or include an additive such as a flavourant, for
instance menthol or coffee (where local regulations permit the use
of such flavourants) or an adsorbent such as activated carbon
granules or an ion exchange resin, giving the filter segment unique
flavouring or filtration properties, and/or a unique end
appearance.
[0061] Including the first fibrous filter material in one or more
regions substantially within the second fibrous filter material can
enable the second fibrous filter material to be plasticised, or
cured, with the first fibrous filter material inserted into the one
or more regions during the manufacturing process, for instance
after a plasticiser has been applied to the second filter material.
This can help to locate the first filter material into a desired
position within the second filter material, which can have the
associated advantage of improving the end appearance of the
filter.
[0062] In each of the first to fifth smoking articles 1, 11, 21,
31, 161 illustrated in FIGS. 1(a) to 1(e), the first fibrous filter
material 3, 13, 23, 33, 163 can, for instance, comprise from 5% to
70% of the total filter segment volume. The fibres of the first
filter material, in the present examples PLA fibres, can, for
instance, have a filament denier of from 2 to 10, more particularly
from 2 to 7, and can be formed using, for instance, between 200 and
10,000 fibres per region in which they are located. The fibres of
the second filter segment, in the present examples CA fibres, can
have a filament denier of from 2 to 10, more particularly from 2 to
7, and between 5,000 and 20,000 fibres can, for instance, be used
to form the filter. Appropriate fibre deniers and numbers of
filaments for each of the first and second filter materials can be
selected according to various factors, such as the crimp applied to
either or each of these materials, the desired ratio of the volumes
of these materials, the desired total denier for the filter, the
desired pressure drop and or hardness for the filter, apparatus
capabilities and desired apparatus operating speeds. The second
fibrous filter material can be plasticised with triacetin, or
another plasticiser, used in an amount from, for instance, 5% to
12% by weight of the plasticised fibres.
[0063] The filter segment 2 of FIG. 1(a) includes 10% by volume of
the first fibrous filter material 3, in that example PLA, and 90%
by volume of plasticised CA, in which triacetin accounts for 8% by
weight of the CA.
[0064] The filter segment 12 of the second smoking article 11
illustrated in FIG. 1(b) includes 12% by volume of the first
fibrous filter material 13, in that example PLA, and 88% by volume
of the second fibrous filter material 14, in that case plasticised
CA, in which triacetin accounts for 8% by weight of the CA. Each
region of the first fibrous filter material 13 comprises 6% of the
total filter segment volume.
[0065] The filter segment 22 of the third smoking article 21
illustrated in FIG. 1(c) includes 16% by volume of the first
fibrous filter material 23, in that example PLA, and 84% by volume
of the second fibrous filter material 24, in that case plasticised
CA, in which triacetin accounts for 8% by weight of the CA. Each of
the four regions of the first fibrous filter material comprises 4%
of the total filter segment volume.
[0066] The filter segment 32 of the fourth smoking article 31
illustrated in FIG. 1(d) includes 20% by volume of the first
fibrous filter material 33, in that example PLA, and 80% by volume
of the second fibrous filter material 34, in that case plasticised
CA, in which triacetin accounts for 8% by weight of the CA. Each of
the five regions of the first fibrous filter material 33 comprises
4% of the total filter segment volume.
[0067] The filter segment 162 of the fifth smoking article 161
illustrated in FIG. 1(e) includes 40% by volume of the first
fibrous filter material 163, in that example PLA, and 60% by volume
of the second fibrous filter material 164, in that case plasticised
CA, in which triacetin accounts for 8% by weight of the CA. Each of
the first and second regions 163a, 163b of the first fibrous filter
material 163 comprises 20% of the total filter segment volume.
[0068] Alternative relative volumes of the first and second fibrous
filter materials can be used, and these will depend on the chosen
materials, the fibre denier of the materials, the number of
filaments used, and the level of crimp which is applied to each
material. The volume of the first fibrous material can, for
instance, comprise up to 20, 25, 30, 35, 40, 45, 50, 55, 60, 65 or
70% of the total filter segment volume. The first fibrous material
can also be used in lower volumes, for instance down to 15, 14, 13,
12, 11, 10, 9, 8, 7, 6, 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5 or 1% of the
total filter segment volume. The volume of the first fibrous
material can, accordingly, fall within a range comprising from one
of 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4.5, 4, 3.5, 3, 2.5, 2,
1.5 or 1% of the total filter segment volume up to one of 20, 25,
30, 35, 40, 45, 50, 55, 60, 65 or 70% of the total filter segment
volume, in particular from 10% to 70% of the total filter segment
volume.
[0069] Each of the regions of first fibrous filter material can
comprise greater than 2%, greater than 2.5%, greater than 3%,
greater than 3.5%, greater than 4% or greater than 5% of the total
filter segment volume, for instance from 2%, 3%, 4% or 5% to 20%,
25% or 30% of the total filter segment volume.
[0070] The first fibrous filter material 3, 13, 23, 33 in the first
to fourth smoking articles is disposed in one or more regions
spaced from the outer longitudinal periphery of the second fibrous
filter material 4, 14, 24, 34, such that the first fibrous filter
material 3, 13, 23, 33 is present at the outer surface of the
cylinder (or other shape) formed by the first and second filter
materials only at each end of the filter segment. However,
alternatively, the first fibrous filter material 3, 13, 23, 33 in
the first to fourth smoking articles can be disposed in a region
part of the boundary of which is coexistent with the outer
periphery of the filter segment formed by the first and second
filter materials such that the first fibrous filter material is
present at the outer surface of the filter segment at each end of
the filter segment and/or at one or more parts of the outer
longitudinal periphery of the filter segment (such latter surfaces
being in contact with a plug wrap in the present examples).
[0071] The first fibrous filter material 3, 13, 23, 33, 163 in the
first to fifth smoking articles is disposed such that it is at the
outer boundary of the respective filter segments 2, 12, 22, 32, 162
at each end of the filter segments. However, alternatively, the
first fibrous filter material 3, 13, 23, 33, 163 can be disposed in
at least one region which is not at the outer boundary of the
second fibrous filter material 4, 14, 24, 34, 164 at either end of
the respective filter segment or which is at the outer boundary of
the filter segment at one but not both ends of the filter
segment.
[0072] The first fibrous filter material 3, 13, 23, 33, 163 in the
first to fifth smoking articles is disposed in up to five separate
regions. However, the first fibrous filter material 3, 13, 23, 33,
163 can be disposed in greater than five regions, such as 6, 7, 8,
9, 10, 11 or 12 regions, so as to provide a desired volume or
weight of the first fibrous filter material 3, 13, 23, 33, 163
within the filter segment 2, 12, 22, 32, 162.
[0073] As used herein, the term filter segment refers to a single
discrete filter component which can be individually attached to a
smoking article. The filter segments 2, 12, 22, 32, 162 used in the
first to fifth smoking articles 1, 11, 21, 31, 161 are mono filter
segments, comprising the entire filter for such smoking articles 1,
11, 21, 31, 161. However, the filter segments 2, 12, 22, 32, 162
can alternatively be used in other filter configurations, such as
the mouth end, tobacco end or both segments of a dual, dual
dalmatian or cavity filters, or one or more of the mouth end,
intermediate and tobacco end segments of a triple or quad filter.
One or more of the segments of the filter may comprise non-wrapped
acetate (NWA) segments.
[0074] The first and/or second fibrous filter materials 3, 4, 13,
14, 23, 24, 33, 34, 163, 164 can comprise mixtures of different
materials, for instance mixtures of fibres of a plurality of
materials or the fibres themselves being formed from blends or
composites of a plurality of materials.
[0075] FIGS. 2 to 4 are schematic illustrations of a first device
40 for inserting a first fibrous filter material into a second
fibrous filter material to produce a filter segment such as those
of the smoking articles illustrated in FIGS. 1(a) to 1(d). Such a
device is described in more detail in International patent
publication WO2010/108739, the contents of which are expressly
incorporated herein by reference, and can be adapted for use in
producing filter segments according to the present invention in the
manner set out below.
[0076] The first device 40, in use, is connected to a filter making
apparatus such as the KDF 2 apparatus produced by Hauni
Maschinenbau AG in Germany and is capable of producing a filter rod
with up to five separate regions of a first fibrous filter material
extending through the cross-section of the filter formed from a
second fibrous filter material. The first device 40 comprises a
tongue 41 having a wide entrance opening 41b and a narrow exit
opening 41a, a funnel 42 and a stuffer jet 43. The filter making
apparatus includes a garniture, filter wrapping paper and wrapping
paper-spool as well as other sections, not illustrated here. The
first device 40 also includes a multi-region material positioning
unit, generally indicated as 44. The multi-region material
positioning unit 44 comprises a support block 45 which is attached
to a support fin 41c which extends vertically upwards from the
tongue 41. The support block 45 is fixedly secured in place on the
fin 41c of the tongue 41 by known connectors such as bolts, welds,
etc.
[0077] The support block 45 includes five apertures 46a-46e
extending therethough. A first aperture 46a extends from the centre
of the top of the support block 45 downwards to the tongue 41, and
second and third apertures 46b, 46c extend from either side of the
first aperture 46a on the top of the support block 45 downwards to
the tongue 41. Furthermore, fourth and fifth apertures 46d, 46e
extend from the left and right sides of the support block 45
respectively, laterally through the support block 45 to the tongue
41. Each aperture 46a-e is inclined at an angle so as not to be
perpendicular to the central axis of the tongue 41 and to point
slightly in the direction of the exit opening 41a, as shown in
FIGS. 2 and 3. The tongue 41 includes a plurality of apertures
47a-47e in its side wall extending through to the bore of the
tongue 41, wherein each of the apertures 47a-e is aligned with one
of the apertures 46a-e in the support block 45, so as to provide a
plurality of continuous passages though the support block 45 and
through the lateral wall of the tongue 41 to the central bore of
the tongue 41.
[0078] Five needles 48a-e are provided, one disposed in each of the
apertures 46a-e in the support block 45 which extend through the
respective aperture 47a-e in the tongue 41. Therefore, each needle
48a-e extends from outside the support block 45, though the support
block 45 and through the wall of the tongue 41 and terminates
within the bore of the tongue 41. The needles have internal passage
diameters appropriate for carrying fibres used to form the regions
of the first filter material used in the filter segments of the
present invention.
[0079] An outer portion of each of the apertures 46a-e in the
support block 45 is of a larger diameter than the inner portion
proximate the tongue 41, and is threaded to receive a
correspondingly threaded locking shaft 49a-e. The locking shafts
49a-e each include a hollow bore (not shown) through which, in use,
a respective needle 48a-e extends, and the locking shaft 49a-e
comprises a first continuous section at its lower end, and a
second, fingered section (not shown) at its upper end. The fingered
section is formed by a plurality of radial slots cut from the top
end of the locking shaft 49a-e downwards and extending all the way
through from the inner bore through to the outside of the locking
shaft 49a-e. The remaining threaded sections of the `fingers` are
thereby defined between the slots and are deflectable in a radial
direction of the locking shaft 49a-e.
[0080] Also shown in FIGS. 2 to 4 are locking nuts 50a-e which
include an internal thread corresponding to the external thread of
the locking shafts 49a-e, and which are shaped to taper inwardly
slightly so that as each locking nut 50a-e is threaded onto the
fingered section of each locking shaft 49a-e, the fingers are
caused to be deflected inwards into the inner bore of the locking
shafts 49a-e. The inner bore of the locking shaft is of the same
diameter as that of the inner portion of the apertures 46a-e which
extend through the support block 45 and of the apertures 47a-e
which are formed in the lateral wall of the tongue 41, so that
needles 48a-e fit snugly in the respective bores of the locking
shafts 49a-e. It will therefore be appreciated that as the locking
nuts 50a-e are threaded and tightened onto the respective locking
shafts 49a-e, they cause the fingers to be deflected inwards, and
so when a needle 48a-e is disposed in the inner bore of the locking
shaft 49a-e, tightening the locking nuts 50a-e causes the fingers
to be biased against the needle 48a-e, thereby fixing the needle
48a-e in the chosen position.
[0081] It will be appreciated that the same effect may be achieved
with a non-tapering locking nut having a constant thread diameter
if the upper part of the locking shaft comprising the fingers
slightly tapers outwards in a direction towards the tongue 41.
Thereby, as the locking nut is threaded further onto the locking
shaft, the fingers would be caused to deform inwards, thereby
binding against the needle 48a-e to fix it in place relative to the
locking shaft and thereby the tongue 41.
[0082] In use, a second fibrous filter material, for instance
continuous fibres of crimped CA filter tow material, is conveyed
through the bore of the tongue 41, and up to five individual
supplies of the first fibrous filter material, for instance
continuous crimped fibrous PLA or other material in thread or
strand form, are fed through the needles 48a-e and entrained in the
flow of the second fibrous filter material, being pulled through
the needles 48a-e as the second material passes through the tongue
41. The supply of the first fibrous filter material to the needles
48a-e can be achieved using a mechanical or electromechanical
delivery device such as feed rollers, a feed conveyor, fluted feed
drum or screw feeder (not shown) configured to feed the first
fibrous material from a continuous supply thereof. Such a
mechanical or electromechanical delivery device can have its speed
adjusted so as to meter the first fibrous material into the second
fibrous filter material at an appropriate rate, for instance
according to the speed of the second fibrous filter material
passing through the tongue 41. The emerging compressed filter rod
which exits from the narrow exit opening 41a in the tongue 41
accordingly has up to five separate continuous regions of the first
material therein extending in an axial direction thereof.
[0083] The exact position of the regions of first fibrous filter
material within the cross-section of the resulting filter rod can
be accurately determined and adjusted since the position of the
first fibre regions in the cross-section of the filter rod is
dictated by the point within the tongue 41 at which the ends of the
needles 48a-e terminate. This can be altered as described above,
with each needle 48a-e being independently adjustable to create a
wide variety of patterns within the resulting filter rod. The
device 40 can accordingly be used to produce filter rods containing
up to five regions of a first fibrous material along the length of
a second fibrous material. Filter rods having fewer than five
regions of the first fibrous material therethrough can be produced
by not feeding supplies of the first fibrous material through one
or more of the needles 48a-e.
[0084] FIGS. 5 to 7 are schematic illustrations of a second device
60 for inserting a first fibrous filter material into a second
fibrous filter material to produce a filter segment such as those
illustrated in FIGS. 1(a) to 1(d).
[0085] The second device 60 of FIGS. 5 to 7 is similar to the first
device 40 of FIGS. 2 to 4. The second device 60 in use, is
connected to a filter making apparatus such as the KDF 2 apparatus
produced by Hauni Maschinenbau AG in Germany and is capable of
producing a filter rod with up to five separate regions of a first
fibrous filter material extending through the cross-section of the
filter formed from a second fibrous filter material. The second
device 60 comprises a tongue 61 having a wide entrance opening 61b
and a narrow exit opening 61a, a funnel 62 and a stuffer jet 63.
The filter making apparatus in which the second device 60 is used
includes a garniture, filter wrapping paper and wrapping
paper-spool as well as other sections, not illustrated here. The
second device 60 also includes a multi-region material positioning
unit, generally indicated as 64. The multi-region material
positioning unit 64 comprises a support block 65 which is attached
to a support fin 61c which extends vertically upwards from the
tongue 61. The support block 65 is fixedly secured in place on the
fin 61c of the tongue 61 by known connectors such as bolts, welds,
etc.
[0086] The support block 65 includes five apertures 66a-66e
extending therethough, similar to the apertures 46a-e of the
support block 45 of the first device. The tongue 61 also includes a
plurality of apertures 67a-67e in its side wall extending through
to the bore of the tongue 61, wherein each of the apertures 67a-e
is aligned with one of the apertures 66a-e in the support block 65,
so as to provide a plurality of continuous passages though the
support block 65 and through the lateral wall of the tongue 61 to
the central bore of the tongue 61.
[0087] Five needles 68a-e are provided, one disposed in each of the
apertures 66a-e in the support block 65 which extend through the
respective aperture 67a-e in the tongue 61. Therefore, each needle
68a-e extends from outside the support block 65, though the support
block 65 and through the wall of the tongue 61 and terminates
within the bore of the tongue 61. Similarly to the first device 40,
the needles 68a-e have internal passage diameters appropriate for
carrying fibres used to form the regions of the first filter
material used in the filter segments of the present invention.
[0088] An outer portion of each of the apertures 66a-e in the
support block 65 is of a larger diameter than the inner portion
proximate the tongue 61, and is threaded to receive a
correspondingly threaded locking shaft 69a-e. The locking shafts
69a-e each include a hollow bore (not shown) through which, in use,
a respective needle 68a-e extends. The locking shafts 69a-e are
similar to those of the first device 40.
[0089] Also shown in FIGS. 5 to 7 are locking nuts 70a-e which are
similar to and operate in the same way as the locking nuts 50a-e of
the first device 40.
[0090] The second device 60 differs from the first device 40 by the
orientation of the first, second and third apertures 66a-c formed
in the support block 65, and thereby the orientation of the
plurality of continuous passages though the support block 65 and
through the lateral wall of the tongue 61 to the central bore of
the tongue 61. Accordingly, the needles 68a-c respectively disposed
in each of the first to third apertures 66a-c are correspondingly
differently orientated.
[0091] It can be seen from FIG. 7 that the first, second and third
needles 68a-c are arranged radially with respect to the central
axis of the tongue 61, as opposed to the first, second and third
needles 48a-c of the first device 40, which are all arranged with
their respective axes parallel to each other. This alternative
orientation of the first, second and third needles 68a-c provides a
different range of first fibrous material region positions to be
achieved within the filter rod and, in particular, allows closer
positioning of these three first fibrous material regions to each
other and to the two other first fibrous material regions from the
fourth and fifth needles 68d-e to be achieved. This is due to the
fact that the radial orientation of the first to third needles
68a-c means that when they are adjusted inwards, the ends of the
needles 68a-c converge towards the central axis of the bore of the
tongue 68, rather than remaining the same spacing from each other
with respect to a horizontal line across the cross-section of the
tongue 61.
[0092] In use, the second device 60 is operated in the same way as
the first device 40 described above. A second fibrous filter
material, for instance continuous fibres of crimped CA filter tow
material, is conveyed through the bore of the tongue 61, and up to
five individual supplies of the first fibrous filter material, for
instance continuous crimped fibrous PLA or other material in the
form of a thread or strands and fed through the needles 68a-e and
entrained in the flow of the second fibrous filter material, being
pulled through the needles 68a-e as the second material passes
through the tongue 61. The supply of the first fibrous filter
material to the needles 68a-e can be achieved using a mechanical or
electromechanical delivery device such as feed rollers, a feed
conveyor, fluted feed drum or screw feeder (not shown) configured
to feed the first fibrous material from a continuous supply
thereof. Such a mechanical or electromechanical delivery device can
have its speed adjusted so as to meter the first fibrous material
into the second fibrous filter material at an appropriate rate, for
instance according to the speed of the second fibrous filter
material passing through the tongue 61. The emerging compressed
filter rod which exits from the narrow exit opening 61a in the
tongue 61 accordingly has up to five separate continuous regions of
the first material therein extending in an axial direction
thereof.
[0093] FIGS. 8 and 9 are schematic illustrations of a third device
80 according to an embodiment of the invention for inserting a
first fibrous filter material into a second fibrous filter material
to produce a filter segment such as that illustrated in FIG.
1(a).
[0094] FIG. 8 shows part of the third device 80 comprising a fibre
insert section 81. During operation of the third device 80, a
second fibrous filter material 82, in the form of cellulose acetate
tow in the present example, is drawn through a set of conveying
rollers (not shown), and is compressed through a stuffer jet (not
shown) and through the tongue 83 of a garniture 84, where it is
paper wrapped with a plugwrap 85 and subsequently cut into segments
by a cutter (not shown) to form filter rods.
[0095] FIG. 9 shows a cross section of the third device 80. The
fibre insert section 81 comprises a fibre feed tube 86, a venturi
insert device 87 and an insert tube 88. The insert tube 88 forms a
fibre transfer path, in the present example from the venture insert
device 87 to the tongue 83, and may be bent so that it can be
aligned longitudinally with the direction in which the filter rod
material 82 is conveyed in the tongue 83. The position of the
insert tube 88 may be adjusted using the insert tube adjustment
wheel 88a shown in FIG. 8. This allows the stream of fibres to be
positioned along the longitudinal axis of the second filter
material 84 or alternatively off-centre but parallel to the
longitudinal axis. The fibre insert section 81 also comprises
first, second and third air jet inlets 89a-c.
[0096] The feed tube 86 is configured to accept fibres of a first
fibrous filter material for insertion into a second fibrous filter
material, the first fibrous material being supplied, for instance,
in the form of a thread or strands of the first fibrous material.
The supply of the first fibrous filter material to the feed tube 86
can be achieved using a mechanical or electromechanical delivery
device such as feed rollers, a feed conveyor, fluted feed drum or
screw feeder (not shown) configured to feed the first fibrous
material from a continuous supply thereof. Such a mechanical or
electromechanical delivery device can have its speed adjusted so as
to meter the first fibrous material into the second fibrous filter
material at an appropriate rate, for instance according to the
speed of the second fibrous filter material passing through the
tongue 83. The emerging compressed filter rod which exits from the
tongue 83 accordingly has a continuous region of the first material
therein extending in an axial direction thereof.
[0097] FIG. 10 is an enlarged cross sectional view of the venturi
device 87 shown in FIG. 8. The venturi device 87 comprises a
generally conical block 90 with an axial bore 91 having an inlet 92
that receives a supply of fibres 93 from the feed tube 86 and an
outlet 94 that supplies the fibres 93 into the insert tube 88.
[0098] The conical block 90 is received within a generally
cylindrical housing 95 with a conical end spaced from the block 90
to define a converging air passageway 96 which opens into the
insert tube 88 in the region of the outlet 94 of the bore 91.
[0099] The air supply passageway 96 is fed with compressed air from
the three air jet inlets 89a-c, the first of which 89a is shown in
FIG. 10. The air jet inlets 89a-c are coupled to a compressed air
or other gas source (not shown) and feed into respective
longitudinal bores 97a,b that connect into the converging air
supply passageway 96. Although the first, second and third jet
inlets 89a-c are fed with air, other fluids could be employed, for
example helium or nitrogen.
[0100] Fibres 93 are received from the feed tube 86 and are
directed into the axial bore 91. Compressed air from the first
inlet 89a is directed along the longitudinal bore 97 towards the
region 94 where the axial bore 91 and the longitudinal bore 97
converge. Compressed air from the second and third inlets 89b, 89c
is also directed along corresponding respective longitudinal bores
(not shown) for these inlets towards the region 94 where the axial
bore 91 and those longitudinal bores converge.
[0101] During operation of the venturi device 87 the Venturi effect
is exploited to propel the fibres 93 towards the filter rod
material 92 as it is formed into filter rods.
[0102] FIG. 11 schematically illustrates the air flow in the
venturi device 87 during operation of the fibre insert section 81.
As air is propelled from the first and second jet sources 89a, 89b
through the longitudinal bores 97a, 97b and into the insert tube
88, an area of low pressure is created in the region 94 and insert
tube 88. The fibres 93 initially occupy an area of high pressure
relative to this low pressure region 94. A pressure gradient force
is created that acts on the fibres 93 and propels them into the
insert tube 88 with a velocity greater than if they were to be
acted upon by the force due to gravity alone. This allows a high
density of fibres 93 to be inserted into the second fibrous filter
rod material. The insert tube 88 feeds into the tongue 83 of the
third device 80 to insert fibres directly into the second fibrous
filter material.
[0103] The position of the insert tube 88 may be adjusted relative
to the longitudinal axis of the filter rod under manufacture. In
FIG. 9 the insert tube 88 is bent however in other embodiments the
insert tube 88 may be straight. The fibres may be centred along the
longitudinal axis of the filter rod or substantially parallel to
but offset from the longitudinal axis using the insert tube
adjustment wheel 88a shown in FIG. 8.
[0104] FIG. 12 is a cross sectional schematic view of a fourth
device 100 in accordance with a further embodiment of the invention
for inserting a first fibrous filter material into a second fibrous
filter material to produce a filter segment such as that
illustrated in FIG. 1(a). The fourth device 100 shown in FIG. 12 is
similar to the third device 80 shown in FIG. 8. However, the fourth
device 100 shown in FIG. 12 comprises a high flow vacuum pump 101
instead of the venturi insert device 87 shown in FIG. 8. The fourth
device 100 also comprises a fibre feed tube 102 and an exit tube
103.
[0105] The high flow vacuum pump 101 may be of a type known in the
art for material transfer such as KVPDF High Flow Vacuum Pumps, or
vacuum pumps such as the DF Series pumps supplied by Vaccon
Company, Inc in the US. Compressed air enters the vacuum pump 101
through an air inlet 104 and flows cyclonically through a central
tube 105 of the pump 101. The cyclonic flow of compressed air
produces a vacuum which can draw fibres from the feed tube 102,
through the central tube 105 and into the exit tube 103 to converge
with the tongue 106 of the garniture (as shown in FIG. 8).
[0106] Compressed air can be supplied to the air inlet 104 at
between 10 and 60 Psi, for instance from 10 to 40 Psi, or
preferably at about 30 Psi.
[0107] The feed tube 102 is configured to accept fibres of a first
fibrous filter material for insertion into a second fibrous filter
material, the first fibrous material being supplied, for instance,
in the form of a thread or strands of the first fibrous material.
The supply of the first fibrous filter material to the feed tube
102 can be achieved using a mechanical or electromechanical
delivery device such as feed rollers, a feed conveyor, fluted feed
drum or screw feeder (not shown) configured to feed the first
fibrous material from a continuous supply thereof. Such a
mechanical or electromechanical delivery device can have its speed
adjusted so as to meter the first fibrous material into the second
fibrous filter material at an appropriate rate, for instance
according to the speed of the second fibrous filter material
passing through the tongue 106. The emerging compressed filter rod
which exits from the tongue 106 accordingly has a continuous region
of the first material therein extending in an axial direction
thereof.
[0108] FIG. 13 is a schematic illustration of a fifth device 110
according to a further embodiment of the invention for inserting a
first fibrous filter material into a second fibrous filter material
to produce a filter segment such as those of the smoking articles
illustrated in FIGS. 1(a) to 1(d).
[0109] The fifth device 110 of FIG. 13 includes components similar
to the second device 60 of FIGS. 5 to 7. The fifth device 110 in
use, is connected to a filter making apparatus such as the KDF 2
apparatus produced by Hauni Maschinenbau AG in Germany and is
capable of producing a filter rod with up to five separate regions
of a first fibrous filter material extending through the
cross-section of the filter formed from a second fibrous filter
material.
[0110] The fifth device 110 comprises a tongue 111 having a wide
entrance opening 111b and a narrow exit opening 111a, a funnel 112
and a stuffer jet 113. The filter making apparatus in which the
fifth device 110 is used includes a garniture, filter wrapping
paper and wrapping paper-spool as well as other sections, not
illustrated here. The fifth device 110 also includes a multi-region
material positioning unit, generally indicated as 114. The
multi-region material positioning unit 114 comprises a support
block 115 which is attached to a support fin 111c which extends
vertically upwards from the tongue 111. The support block 115 is
fixedly secured in place on the fin 111c of the tongue 111 by known
connectors such as bolts, welds, etc.
[0111] The support block 115 includes five apertures 116a-116e
extending therethough, similar to the apertures 66a-e of the
support block 65 of the second device. The tongue 111 also includes
a plurality of apertures (not shown) in its side wall extending
through to the bore of the tongue 111, wherein each of the
apertures is aligned with one of the apertures 116a-e in the
support block 115, so as to provide a plurality of continuous
passages though the support block 115 and through the lateral wall
of the tongue 111 to the central bore of the tongue 111.
[0112] Five needles 118a-e are provided, one disposed in each of
the apertures 116a-e in the support block 115 which extend through
the respective apertures in the tongue ill.
[0113] Therefore, each needle 118a-e extends from outside the
support block 115, though the support block 115 and through the
wall of the tongue 111 and terminates within the bore of the tongue
111. Similarly to the second device 60, the needles 118a-e have
internal passage diameters appropriate for carrying fibres used to
form the regions of the first filter material used in the filter
segments of the present invention.
[0114] The fifth device also includes locking shafts 119a-e and
locking nuts 120a-e which are similar to and operate in the same
way as those of the first and second devices 40, 60.
[0115] The fifth device 110 differs from the second device 60 in
that a fibre insert section is connected to each of the needles
118a-e (although only illustrated in respect of the fourth needle
118d in FIG. 13). The fibre insert sections correspond to the fibre
insert section 81 of FIGS. 8 and 9. The fibre insert section 130
connected to the fourth needle 118d comprises a fibre feed tube 131
and a venturi insert device 132. The venturi devices 132 each
comprise a generally conical block with an axial bore having an
inlet that receives a supply of fibres from the feed tube 131 and
an outlet that supplies the fibres into the needles 118. Air supply
passageways within the venture devices 132 are fed with compressed
air from the three air jet inlets 133a-c. The venturi insert device
132 has its fibre stream outlet connected to the fourth needle
118d. The fourth needle 118d forms a fibre transfer path, in the
present example from the venture insert device 132 to the tongue
111. The fibre insert sections (not shown) connected to the first,
second, third and fifth needles 118a,b,c,e comprise corresponding
features to those of the fibre insert section 130 connected to the
fourth needle 118d.
[0116] In use, the fibre insert sections operate in a corresponding
manner to the fibre insert section 81 of FIGS. 8 and 9, with the
venturi device in each section operating in the same manner as the
venturi device 87 described with reference to FIGS. 10 and 11.
Accordingly, during operation of the fifth device 110, a second
fibrous filter material, in the form of cellulose acetate tow in
the present example, is drawn through a set of conveying rollers
(not shown), and is compressed through the stuffer jet 113 and
through the tongue 111 of a garniture, where it is paper wrapped
with a plugwrap and subsequently cut into segments by a cutter (not
shown) to form filter rods. At the same time, the venturi devices
of each fibre insert section are operated by supplying compressed
air to the air inlets 133a-c at between 10 and 60 Psi, for instance
from 10 to 40 Psi, or preferably at about 30 Psi such that the
Venturi effect is exploited to propel fibres of a first filter
material into regions of the second filter material as it is formed
into filter rods.
[0117] FIG. 14 is a schematic illustration of a sixth device 140
according to a further embodiment of the invention for inserting a
first fibrous filter material into a second fibrous filter material
to produce a filter segment such as that illustrated in FIG.
1(e).
[0118] The sixth device 140 of FIG. 14 is, in use, is connected to
a filter making apparatus such as the KDF 2 apparatus produced by
Hauni Maschinenbau AG in Germany and is capable of producing a
filter rod with a region of a first fibrous filter material
extending through the cross-section of the filter formed from a
second fibrous filter material.
[0119] The sixth device 140 comprises a tongue 141, a funnel 142
and a stuffer jet 143. The filter making apparatus in which the
second device 140 is used includes a garniture, filter wrapping
paper and wrapping paper-spool as well as other sections, not
illustrated here.
[0120] The sixth device 140 also includes a fibre insert unit 144
used to supply a first fibrous filter material into the stuffer jet
143. Although only one fibre insert unit 144 is shown, two, three
or more fibre insert units 144 can be used simultaneously. The
fibre insert unit 144, in the present example, comprises a DF
Series vacuum pump as supplied by Vaccon Company, Inc in the US.
The fibre insert unit 144 includes a fibre insert tube 145 used to
feed a first filter material into a second fibrous filter material
flow 146 passing through the stuffer jet 143. The fibre insert unit
144 is mounted on an adjustable support member (not shown), which
enables the position of the outlet of the tube 145 in relation to
the stuffer jet 143 to be accurately set. The fibre insert unit 144
further comprises a fibre inlet 147 for receiving a supply of first
fibrous material and a compressed ait inlet 148 for receiving a
supply of compressed air, for instance at between 10 and 60 Psi,
for instance from 10 to 40 Psi, or about 30 Psi.
[0121] In use, the fibre insert unit 144 is supplied with
compressed air and creates an internal vacuum forcing a supply of a
first fibrous filter material as hereinbefore described into the
stuffer jet 143. Accordingly, during operation of the sixth device
140, a second fibrous filter material, in the form of cellulose
acetate tow in the present example, is drawn through a set of
conveying rollers (not shown), and is compressed through the
stuffer jet 143 and through the tongue 141 of a garniture, where it
is paper wrapped with a plugwrap and subsequently cut into segments
by a cutter (not shown) to form filter rods. At the same time, the
fibre insert unit 144 is operated such that fibres of a first
filter material are transported into a region of the second filter
material as it is formed into filter rods.
[0122] The sixth device 140 has the advantage that the first filter
material is inserted into the second filter material at a point
upstream of the tongue 141 where the second filter material is
relatively uncompressed. This can enable more diverse regions of
first filter material to be inserted into a second fibrous filter
material, forming shapes such as the elongate sections described
with reference to FIG. 1(e).
[0123] Although only one fibre insert unit 144 is used in the
example illustrated in FIG. 14, multiple fibre insert unit 144 can
be inserted into the stuffer jet, for instance 2, 3, 4, 5 or 6
separate tubes, each having corresponding adjustable support
members.
[0124] Although a venturi device 132 has been used in the fifth
device 110, of FIG. 13, alternatively a high flow vacuum pump such
as that described with reference to FIGS. 12 and 14 can be used in
place of one or more of the venturi devices 132 (i.e. each of the
first to fifth devices of the fifth device 110 of FIG. 13).
[0125] The embodiments of FIGS. 8 to 14, by using a fluid stream to
insert a first fibrous filter material into a second fibrous filter
material can insert the first fibrous filter material at a greater
rate than the flow rate of the second fibrous filter material. Such
feeding is referred to as over-feeding and can, for instance, be
used to insert the first fibrous filter material such that the
ratio of the second fibrous filter material rate:first fibrous
filter material rate is in the range 1:1.1 to 1:2, more preferably
in the range 1:1.1 to 1:1.5.
[0126] In order to address various issues and advance the art, the
entirety of this disclosure shows by way of illustration various
embodiments in which the claimed invention(s) may be practiced and
provide for superior filters, filter production methods, smoking
articles and filter production devices. 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 teach the claimed features. 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 and/or
spirit of the disclosure. Various embodiments may suitably
comprise, consist of, or consist essentially of, various
combinations of the disclosed elements, components, features,
parts, steps, means, etc. In addition, the disclosure includes
other inventions not presently claimed, but which may be claimed in
future.
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