U.S. patent application number 14/900931 was filed with the patent office on 2016-05-19 for method and an apparatus for manufacturing a filter for a smoking article.
The applicant listed for this patent is BRITISH AMERICAN TOBACCO (INVESTMENTS) LIMITED. Invention is credited to Gary FALLON.
Application Number | 20160135496 14/900931 |
Document ID | / |
Family ID | 48999053 |
Filed Date | 2016-05-19 |
United States Patent
Application |
20160135496 |
Kind Code |
A1 |
FALLON; Gary |
May 19, 2016 |
Method and an apparatus for manufacturing a filter for a smoking
article
Abstract
A method and an apparatus for manufacturing a filter for a
smoking article Embodiments of the invention relate to a method and
an apparatus for manufacturing a filter for a smoking article, and
a smoking article produced by the method. The method can include
forming a filter section having a surface relief pattern with a
filter forming device, transferring the filter section to a filter
wrapping device with a filter transfer device and wrapping a sheet
material around the filter section with the filter wrapping
device.
Inventors: |
FALLON; Gary; (London,
GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BRITISH AMERICAN TOBACCO (INVESTMENTS) LIMITED |
London |
|
GB |
|
|
Family ID: |
48999053 |
Appl. No.: |
14/900931 |
Filed: |
June 27, 2014 |
PCT Filed: |
June 27, 2014 |
PCT NO: |
PCT/GB2014/051970 |
371 Date: |
December 22, 2015 |
Current U.S.
Class: |
131/331 ;
493/46 |
Current CPC
Class: |
A24D 3/0258 20130101;
A24D 3/04 20130101; A24D 3/0229 20130101; A24D 3/0275 20130101;
A24D 3/0233 20130101 |
International
Class: |
A24D 3/02 20060101
A24D003/02; A24D 3/04 20060101 A24D003/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 27, 2013 |
GB |
1311450.9 |
Claims
1. A method of manufacturing a filter for a smoking article,
comprising: forming a filter section having a surface relief
pattern with a filter forming device; transferring the filter
section having the surface relief pattern to a filter wrapping
device, using a filter transfer device; and wrapping a sheet
material around the filter section having the surface relief
pattern with the filter wrapping device.
2. A method according to claim 1, wherein the filter section is
transferred automatically from the filter forming device to the
filter wrapping device by the filter transfer device, in a
continuous assembly process.
3. A method according to claim 1 or 2, wherein wrapping the sheet
material around the filter section having the surface relief
pattern takes place before the surface relief pattern is
substantially lost by elastic expansion of the filter section.
4. A method according to any preceding claim, wherein the time
between forming the filter section having a surface relief pattern
and wrapping the sheet material around the filter section is less
than 2 minutes, less than 1 minute, less than 30 seconds, less than
20 seconds, less than 10 seconds, less than 2 seconds or less than
1 second.
5. A method according to claim 1, wherein forming the filter
section comprises: forming a cylinder of filtration material; and
shaping the cylinder of filtration material to have the surface
relief pattern.
6. A method according to claim 5, wherein shaping the cylinder of
filtration material comprises passing the cylinder of filtration
material through at least one shaping device.
7. A method according to claim 5, wherein the cylinder of
filtration material is shaped by wrapping with a plug wrap having
one or more weakened sections.
8. A method according to any preceding claim, wherein the surface
relief pattern comprises a plurality of grooves extending in a
longitudinal direction along said filter section.
9. A method according to any preceding claim, wherein transferring
the filter section comprises translating linear movement of the
filter section into rotational movement.
10. An apparatus for manufacturing a filter for a smoking article,
comprising: a filter forming device for forming a filter section
having a surface relief pattern; a filter wrapping device for
wrapping a sheet material around the filter section having the
surface relief pattern; and a filter transfer device arranged to
transfer the filter section having the surface relief pattern from
the filter forming device to the filter wrapping device.
11. Apparatus according to claim 10, wherein the filter transfer
device is arranged to transfer the filter section automatically
from the filter forming device to the filter wrapping device in a
continuous assembly process.
12. Apparatus according to claim 10 or 11, wherein the apparatus is
configured to operate such that wrapping the sheet material around
the filter section having the surface relief pattern takes place
before the surface relief pattern is substantially lost by elastic
expansion of the filter section.
13. Apparatus according to claim 10, 11 or 12, wherein the
apparatus is configured to operate such that the time between
forming the filter section having a surface relief pattern and
wrapping the sheet material around the filter section is less than
2 minutes, less than 1 minute, less than 30 seconds, less than 20
seconds, less than 10 seconds, less than 2 seconds or less than 1
second.
14. Apparatus according to any one of claims 10 to 13, further
comprising a shaping device for shaping the cylinder of filtration
material to have the surface relief pattern.
15. Apparatus according to claim 14, wherein the filter forming
device comprises a garniture for forming a cylinder of the
filtration material and the garniture comprises a shaping garniture
configured to impress the surface relief pattern onto a cylinder of
filtration material passed through the garniture.
16. Apparatus according to any one of claims 10 to 13, wherein the
filter forming device is configured to wrap a plug wrap having one
or more weakened areas around the filter section.
17. Apparatus according to any one of claims 10 to 16, wherein the
surface relief pattern comprises a plurality of grooves extending
in a longitudinal direction along said filter section.
18. Apparatus according to any one of claims 10 to 17, wherein the
filter transfer device is arranged to translate linear movement of
the filter section into rotational movement.
19. A smoking article filter produced by the method of any one of
claims 1 to 9.
20. A smoking article including a smoking article filter according
to claim 19.
Description
TECHNICAL FIELD
[0001] Embodiments of the invention relate to a method and an
apparatus for manufacturing a filter for a smoking article, and a
smoking article produced by the method.
BACKGROUND
[0002] Filters for cigarettes can be compressed to give a shape to
the outer surface. A filter may be compressed to form grooves in
the outer surface thereof. In some examples, a grooved filter may
provide a flow of ventilated air. In other examples, a grooved
filter may provide an enhanced tactile experience.
SUMMARY
[0003] According to embodiments of the invention, there is
provided, in a first aspect, a method of manufacturing a filter for
a smoking article, comprising forming a filter section having a
surface relief pattern with a filter forming device, transferring
the filter section having the surface relief pattern to a filter
wrapping device, using a filter transfer device, and wrapping a
sheet material around the filter section having the surface relief
pattern with the filter wrapping device.
[0004] The filter section can be transferred automatically from the
filter forming device to the filter wrapping device by the filter
transfer device, in a continuous assembly process.
[0005] Wrapping the sheet material around the filter section having
the surface relief pattern can take place before the surface relief
pattern is substantially lost by elastic expansion of the filter
section. The time between forming the filter section having a
surface relief pattern and wrapping the sheet material around the
filter section can be less than 2 minutes, less than 1 minute, less
than 30 seconds, less than 20 seconds, less than 10 seconds, less
than 2 seconds or less than 1 second.
[0006] Forming the filter section can comprise forming a cylinder
of filtration material having the surface relief pattern and
dividing the cylinder of filtration material to form a plurality of
filter sections.
[0007] Forming the filter section can comprise forming a cylinder
of filtration material and shaping the cylinder of filtration
material to have the surface relief pattern.
[0008] Forming the cylinder of filtration material can comprise
passing filtration material through at least one tapering
guide.
[0009] Shaping the cylinder of filtration material can comprise
passing the cylinder of filtration material through at least one
shaping device.
[0010] The cylinder of filtration material can be shaped by
wrapping with a plug wrap having one or more weakened sections.
[0011] The surface relief pattern can comprises a plurality of
grooves extending in a longitudinal direction along said filter
section.
[0012] Wrapping a sheet material around the filter section can
comprise affixing a blank of sheet material to the filter section
and rolling the filter section such that the blank is wrapped
around the filter section.
[0013] The method can further comprise attaching the blank to a
plurality filter sections.
[0014] The method can further comprise attaching the blank to at
least one tobacco rod.
[0015] Transferring the filter section can comprise translating
linear movement of the filter section into rotational movement.
Transferring the filter section can comprise translating linear
movement of the filter section in the direction of a first axis
into rotational movement about a second axis parallel to the first
axis. The filter section can be held parallel to the first axis by
the filter transfer device.
[0016] According to embodiments of the invention, there is
provided, in a second aspect, an apparatus for manufacturing a
filter for a smoking article, comprising a filter forming device
for forming a filter section having a surface relief pattern, a
filter wrapping device for wrapping a sheet material around the
filter section having the surface relief pattern, and a filter
transfer device arranged to transfer the filter section having the
surface relief pattern from the filter forming device to the filter
wrapping device.
[0017] The filter transfer device can be arranged to transfer the
filter section automatically from the filter forming device to the
filter wrapping device in a continuous assembly process.
[0018] The apparatus can be configured to operate such that
wrapping the sheet material around the filter section having the
surface relief pattern takes place before the surface relief
pattern is substantially lost by elastic expansion of the filter
section.
[0019] The apparatus can be configured to operate such that the
time between forming the filter section having a surface relief
pattern and wrapping the sheet material around the filter section
is less than 2 minutes, less than 1 minute, less than 30 seconds,
less than 20 seconds, less than 10 seconds, less than 2 seconds or
less than 1 second.
[0020] The filter forming device can comprise a garniture for
forming a cylinder of the filtration material.
[0021] The apparatus can further comprise a shaping device for
shaping the cylinder of filtration material to have the surface
relief pattern.
[0022] The filter forming device can comprise a garniture for
forming a cylinder of the filtration material and the garniture can
comprise a shaping garniture configured to impress the surface
relief pattern onto a cylinder of filtration material passed
through the garniture.
[0023] The shaping device can comprise a shaping plate configured
to impress the surface relief pattern onto a cylinder of filtration
material rolled over the plate.
[0024] The filter forming device can be configured to wrap a plug
wrap having one or more weakened areas around the filter
section.
[0025] The surface relief pattern can comprise a plurality of
grooves extending in a longitudinal direction along said filter
section.
[0026] The filter wrapping device can comprise a wrapping drum
comprising at least one recess for holding the filter section, a
feeder drum arranged to affix a blank of sheet material to the
filter section, and a rolling element arranged to roll the filter
section such that the blank is wrapped around the filter
section.
[0027] The filter wrapping device can comprise a filter combining
machine, wherein the recess of the wrapping drum is arranged to
hold a plurality of filter sections, and the feeder drum is
arranged to affix the blank of sheet material to the plurality of
filter sections.
[0028] The filter wrapping device can comprise a cigarette making
machine wherein the recess of the wrapping drum is arranged to hold
one or more tobacco rods and the feeder drum is arranged to affix
the blank of sheet material to the one or more filter sections and
the one or more tobacco sections held by the recess.
[0029] The filter transfer device can be arranged to translate
linear movement of the filter section into rotational movement. For
instance, the filter transfer device can be arranged to translate
linear movement of the filter section in the direction of a first
axis into rotational movement about a second axis parallel to the
first axis.
[0030] The filter transfer device can comprise a plurality of
receptacles arranged to receive one or more filter sections,
wherein the receptacles hold the one or more filter sections
parallel to the first axis.
[0031] According to embodiments of the invention, there is
provided, in a third aspect, a smoking article filter produced by
the method set out above.
[0032] According to embodiments of the invention, there is
provided, in a fourth aspect, a smoking article including a smoking
article filter as set out above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Embodiments of the invention will now be described, by way
of example only, with reference to the accompanying drawings, in
which:
[0034] FIG. 1 is a perspective view of a smoking article having
filter with a surface relief pattern of grooves channelling a flow
of ventilating air;
[0035] FIG. 2 is a schematic illustration of an apparatus for
manufacturing a smoking article, the apparatus including a filter
forming device, a filter transfer device and a filter wrapping
device;
[0036] FIG. 3 is a schematic illustration of the filter forming
device of FIG. 2;
[0037] FIG. 4 is a perspective illustration of inner wrapping
material for use by the filter forming device of FIG. 3;
[0038] FIG. 5 is a perspective view of the filter transfer device
of FIG. 2;
[0039] FIG. 6 is flow diagram illustrating a method of
manufacturing a smoking article; and
[0040] FIG. 7 is a perspective illustration of a smoking article
having an indexing mechanism formed by ridges in a filter
section.
DETAILED DESCRIPTION
[0041] 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, also heat-not-burn
products and nicotine delivery devices such as electronic
cigarettes. The smoking article may be provided with a filter for
the gaseous flow drawn by the smoker.
[0042] A smoking article formed by the apparatus or method
described herein can comprise an elongate source of smokable
material. In particular, the smokable material can be tobacco
arranged in a cylindrical tobacco rod. One or more filters or
filter sections can be attached to the tobacco rod. The filter or
filter sections define a longitudinal axis, which is common to a
longitudinal axis of the tobacco rod.
[0043] FIG. 1 illustrates a first exemplary smoking article 10,
which may be manufactured using the apparatus or method described
herein. The smoking article has a filter with a surface relief
pattern of grooves channelling a flow of ventilating air. This
smoking article 10 is illustrated by example only, and the
apparatus and method may be used in the manufacture of different
types of smoking article.
[0044] The smoking article 10 comprises a first part comprising a
source of smokable material. In this example, the smokable material
is tobacco, in the form of a tobacco rod 20. The smoking article
further comprises a filter section 30 attached to the source of
smokable material. The tobacco rod 20 and filter section 30 may be
connected with a covering layer 40 to affix the filter section 30
to the tobacco rod 20, for example formed of a sheet material, e.g.
tipping paper.
[0045] The filter section 30 has a plurality of depressions 32
which form a surface relief pattern on an outer surface thereof. In
particular, the filter section 30 has an outer surface which is not
smooth, comprising a plurality of elongate grooves 32, separated by
ridges 33, which extend, in the present example, substantially
longitudinally along the length of the filter section 30. The
plurality of ridges 33 and grooves 32 may define a sinuous outer
surface, which smoothly oscillates in radius. The ridge 33 between
adjacent depressions 32 may have a curved profile with a
substantially uniform radius of curvature. Alternatively, the
grooves 32 may be formed as flutes, having a concave profile. The
ridge 33 between adjacent depressions 32 may have a pointed,
creased, or tapering profile, having a substantially sharp point of
maximum radius.
[0046] The filter section 30 may be made of filtration material(s)
34, including but not limited to cellulose acetate tow. The filter
section 30 further comprises one or more sheets of inner wrapping
material 35, for example paper, e.g. plugwrap, which is wrapped
around the filtration material 34. The paper 35 extends around the
curved sides of the filter section 30. The paper 35 forms, or
supports, a continuous outer surface defining the grooves 32 and
ridges 33 of the filter section 30. The paper 35 is deformed to
form the grooves 32 and ridges 33, as will be described in greater
detail below.
[0047] The filter section 30 is wrapped with a sheet of outer
wrapping material 40, e.g. tipping paper. The outer wrapping
material 40 may be affixed to the filter section 30 by an area of
adhesive on an inner surface thereof. The outer wrapping material
40 is wrapped around the circumference of the filter section 30 and
adhered at a region where parts of the material 40 overlap, forming
a cylinder of material 40 substantially covering the filter section
30.
[0048] The outer wrapping material 40 comprises one or more
ventilation areas 41, which may include ventilation apertures
and/or air permeable material. The grooves 32 of the filter section
30 form a plurality of ventilation pathways, which connect the
ventilation areas 41 to a mouth end of the smoking article 10.
Ventilating air can pass through the ventilating areas 41, into the
ventilation pathways formed by the grooves 32, and to the mouth end
of the smoking article 10.
[0049] An apparatus and a method in accordance with embodiments of
the invention for producing a filter having a relief pattern on an
outer surface thereof, will be described with reference to FIGS. 2
to 6.
[0050] Referring to FIG. 2, an apparatus for manufacturing a filter
for a smoking article includes a filter forming device 100 arranged
to form a filter section having a surface relief pattern, a filter
wrapping device 300 for wrapping a sheet material around the filter
section and a filter transfer device 200 arranged to transfer the
filter section from the filter forming device 100 to the filter
wrapping device 300.
[0051] A continuous filter assembly line is provided in the
illustrated example. Filter sections are accordingly transferred
mechanically from the filter forming device 100 to the filter
transfer device 200 and from the filter transfer device 200 to the
filter wrapping device 300. According to the illustrated example,
the continuous filter assembly line does not require a hopper to
hold a plurality of filter sections for collection by the filter
wrapping device 300. For instance, neither the filter forming
device 100, filter transfer device 200 nor the filter wrapping
device 300 requires a hopper.
[0052] Referring to FIG. 3, the filter forming device 100 comprises
a garniture 110 and a guide funnel 120, which can comprise a
stuffer jet. The garniture 110 is a passage in the form of a duct
of tube, having a wide entrance opening in and a narrow exit
opening 114. The garniture narrows in a first `tow guide` or
`garniture tongue` portion 112, extending from the wide entrance
opening 111. A second section 113 of the garniture, extending
between the tow guide portion 112 and the narrow exit opening 114,
is substantially constant in cross-section along its length.
Alternatively, the second section 113 may continue to taper but
more gently than the tow guide portion 112.
[0053] The garniture 110 is generally circular in cross-section. A
continuous garniture belt 130 extends through the garniture 110 and
over a plurality of guide rollers 131 and is driven to be conveyed
around the rollers 131 in the direction shown by the arrows A.
Loose filter tow material, such as loose cellulose acetate fibre,
is fed into the funnel 120 and is guided into the tow guide portion
112 of the garniture 110. The filter tow material is conveyed
through the tapering tow guide portion 112 on the plug wrap so that
the loose filter tow material is formed into a more compacted rod
as it emerges from the narrow end of the garniture 114.
[0054] The length of the garniture 110 defines a first longitudinal
axis of the filter forming device 100, along which the filter tow
material is conveyed by the garniture belt 130. The compacted
filter rod extends along the first longitudinal axis of the filter
forming device 100, and exits the filter forming device 100 moving
in a linear fashion along the first longitudinal axis.
[0055] In some embodiments, a plug wrap is fed from a spool 140
onto the upper surface of the garniture belt 130 and is conveyed
through the garniture 110 by the moving garniture belt 130. As the
plug wrap travels through the garniture 110 the shape of the
tapered tow guide 112 deforms the garniture belt 130 and plug wrap
thereon such that, in cross-section, the plug wrap goes from being
flat (as it is on the spool 140) when it enters the wide entrance
opening in of the garniture 110, to a closed circle as it leaves
the narrow exit opening 114 of the garniture 110, completely
surrounding the formed filter rod.
[0056] As the plug wrap is wrapped around the filtration material,
the edges meet to form a seam at an upper portion of the garniture
110. This seam may then be glued or, alternatively, the plug wrap
may be pre-glued where the seam is to be formed. A section of the
upper portion of the garniture 110 may comprise a heating bar to
heat and activate the glue at the seam of the plugwrap to adhere
the plugwrap in place around the filtration material.
Alternatively, hot melt glue is applied to the plug wrap and a
cooling bar may be present in place of a heating bar.
[0057] As the filter tow material travels through the garniture 110
and is compressed, the plug wrap is folded around the outside of
the compressed cylinder of filter tow material and glue is applied
to the over-lapping seam and heated to activate the glue, such that
when the filter tow material exits through the narrow exit opening
114 of the garniture 110, the filter tow material is formed into a
compressed cylindrical filter rod enveloped by an outer plug
wrap.
[0058] In an alternative embodiment, the filter rod may be formed
in the garniture 110 without a plug wrap, and the plug wrap may be
subsequently wrapped around the formed filter rod once it has
exited the garniture 110, or the filter rod may be provided as a
non-wrapped acetate (NWA) rod.
[0059] A shaping device (not shown) associated with the filter
forming device 100 is used to form a filter rod having a surface
relief pattern. In some embodiments, the shaping device is formed
as an integral part of the first garniture 110 or, alternatively,
may comprise a second shaping garniture in series with the first
garniture 110. The inner wall of the garniture may be provided with
a plurality of ribs projecting inwardly and extending
longitudinally towards the narrow exit opening of the garniture. As
the filter tow material travels through the garniture, the ribs on
the inner surface of the garniture wall, which may be heated,
impress a grooved pattern on the outer surface of the filter rod so
that when the filter rod exits through the narrow exit opening of
the garniture, it has a series of longitudinal grooves formed
around its outer surface. It will be appreciated that in this
embodiment, the garniture belt is sufficiently thin and flexible
that the grooved shape can be effectively imparted onto the filter
rod by the ribs through the thickness of the garniture belt.
[0060] In another example of the shaping device the garniture belt
may comprise one or more protrusions, for instance integrally
formed with the garniture belt or provided as a coating or
material, formed on one side which is set thereon with the desired
surface relief pattern. The protrusions are sufficiently flexible
to enable the garniture belt to deform into a rolled up state and
may have heat applied thereto to impress the surface relief pattern
on the filter rod. Alternatively, the garniture belt may comprise a
plurality of linked plates configured to deform from a flat state
to a rolled up state in which they are rolled up about their
longitudinal axis. As the garniture belt enters and is conveyed
through the tow guide portion, the garniture belt is deformed from
its flat state to its rolled up state. As the garniture belt
reaches the narrow end of the garniture, the garniture belt forms a
closed circle in cross-section and the loose filter tow material is
formed in a compact rod circumscribed by the garniture belt.
[0061] In some examples, the shaping device is arranged to receive
the compressed filter rod from the garniture 110. The shaping
device may comprise a plate provided with a plurality of
projections for forming the desired surface relief pattern. The
plate may comprise a plurality of longitudinally extending
projections for forming grooves on an outer surface of the filter
rod. The filter rod is rolled laterally across the plate such that
a grooved pattern is impressed on the outer surface by the
plurality of projections. The filter rod may be divided into a
plurality of filter sections which are rolled across the plate of
the shaping device. A second plate moves laterally across the
plate, in a direction perpendicular to the longitudinal axis of the
filter forming device 100. The filter sections are placed between
the plates and rolled laterally over the plurality of projections
to form the desired surface relief pattern. Reference is directed
to WO 2010/115675, the content of which is hereby expressly
incorporated by reference herein in its entirety, for further
details of a suitable shaping device.
[0062] As the filter tow material travels through the shaping
device, the desired surface relief pattern is impressed on the
outer surface of the filter rod so that when the filter rod exits
the shaping device, it has the desired surface relief pattern, e.g.
in the present examples a series of longitudinal grooves, formed
around the entire perimeter of its outer surface.
[0063] In some embodiments, the shaping device is a garniture no
which forms the desired surface relief pattern by wrapping the
compressed filtration material with a plug wrap. The surface relief
pattern is, for instance, formed by embossing, crimping or
otherwise weakening the plug wrap prior to wrapping around the
filter rod. Compression of the filtration material can lead to
recovery expansion upon exiting the garniture. The weakened areas
of the plug wrap allow for a faster rate of expansion, such that a
surface relief pattern is formed. FIG. 4 illustrates a spool 140
supplying an exemplary plug wrap 150 having a plurality of weakened
areas 151, formed in this examples as embossed sections. In some
embodiments, the plug wrap 150 may be embossed with a plurality of
parallel lines extending longitudinally. When wrapped around the
compressed filtration rod, the embossed lines allow a faster rate
of expansion and form a plurality of ridges on the outer surface of
the filter rod, similar to the ridges 33 illustrated in FIG. 1.
[0064] In order for the surface relief pattern to remain set in the
filter rod, a plasticiser can be mixed with the cellulose acetate
fibres to set the fibres in the shape formed by the shaping
device.
[0065] In some embodiments, as briefly described above, the shaping
device may include a heating means which accelerates the reaction
of the plasticiser. The heating means may, for instance, comprise
inlet ducts along the length of the garniture no through which
steam can be injected. In order that the heat of the steam can be
most efficiently applied to the cellulose acetate and plasticiser
mix, the garniture belt may be porous to allow steam therethrough.
Alternatively, the garniture may comprise one or more heating
elements along its length, such that the heat required to activate
and accelerate the reaction of the plasticiser and the cellulose
acetate of the filtration material is provided directly by
conduction from the heating element through the wall of the
garniture 110.
[0066] The filter forming device 100 further comprises a cutting
tool (not shown) which divides the continuous filter rod into a
plurality of filter sections. The cutting tool comprises one or
more blades located on the outer surface of a rotating cutting
drum. The cutting drum rotates such that the blade passes through
the continuous filter rod as it moves past the cutting drum, and
separates the filter rod into filter sections. Alternatively, the
blade is located on a cutting bar lying perpendicular to the
continuous filter rod, and is passed through the filter rod by
reciprocal linear motion of the cutting bar. In some embodiments,
the cutting tool may be positioned between the garniture 110 and
the shaping tool of the filter forming device 100.
[0067] The filter wrapping device 300, in the present example, is a
cigarette maker comprising a wrapping drum configured to wrap a
layer of sheet material, such as the outer wrapping material 40,
around the filter section. The outer wrapping material 40 is also
wrapped around a portion of a tobacco rod to connect the tobacco
rod to the filter section. The wrapping drum comprises a plurality
of recesses on an outer surface thereof each of which is arranged
to receive at least one filter section, in alignment with a tobacco
rod. A blank for forming the layer of tipping paper or other outer
wrapping material is affixed to the filter section and tobacco rod
whilst the one or more filter sections are held by the recesses of
the wrapping drum. The blank is affixed to the filter section and
tobacco rod at a first end of the blank such that the blank extends
away from the filter section and tobacco rod when attached only at
the first end of the blank.
[0068] A sheet material supply provides the outer wrapping material
for the blank in a continuous length of material to a feeder drum,
which holds the sheet material to an outer surface thereof by
suction means. The feeder drum is rotated in an opposite sense to a
sheet material cutter, comprising a plurality of blades spaced
circumferentially around a rotational axis. The outer wrapping
material is rotated such that it passes between the feeder drum and
the sheet material cutter. The blades of the cutter are positioned
to divide the outer wrapping material into a plurality of blanks
for wrapping around a filter section.
[0069] Adhesive is applied to the outward facing surface of the
blanks whilst they are held on the outer surface of the feeder
drum. Alternatively, adhesive is pre-applied to the continuous
supply of sheet material provided to the feeder drum. The feeder
drum presents the blanks with adhesive applied to the plurality of
filter sections at an interface between the feeder drum and the
wrapping drum. The first end of the blank is aligned with at least
one of the filter sections and pressure is applied between the
feeder drum and the wrapping drum to activate the adhesive on the
surface of the blank. The blank is affixed to at least one filter
section and the combined filter section and blank continues to
rotate on the outer surface of the wrapping drum.
[0070] The blank is wrapped around the section by rolling the
filter section around the outer surface of the wrapping drum. A
stationary rolling element is configured to cooperate with the
wrapping drum to apply pressure to the filter section, thereby
rolling the filter section between the wrapping drum and rolling
element. In some embodiments, the rolling element may comprise a
rolling drum rotating in an opposite sense to the wrapping drum.
The differential in linear speed at the interface between the
wrapping drum and the rolling drum causes rotation of the filter
section and wraps the tipping paper to form a cylinder around the
filter section.
[0071] The filter wrapping device may alternatively be a filter
combining machine configured to wrap a blank around a plurality of
filter sections. Two or more filter sections are held by each
recess of a wrapping drum and a blank is affixed to the plurality
of filter sections. Alternatively, the filter wrapping device may
be configured to wrap a blank around individual filter
sections.
[0072] The apparatus comprises a transfer device 200 which receives
the plurality of filter sections from the filter forming device 100
and provides the plurality of filter sections to the filter
wrapping device 300. The transfer device 200 translates linear
movement of the filter sections into a rotational movement. The
filter sections exit the filter forming device 100 in a direction
parallel to the first longitudinal axis of the filter forming
device 100, which defines the longitudinal axis along which the
compressed filter rod extends. In some embodiments, the transfer
device 200 translates linear movement of the filter sections along
the first longitudinal axis of the filter forming device 100, into
rotational movement around a second longitudinal axis substantially
parallel to the first longitudinal axis, for supply to the filter
wrapping device 300. The orientation of the filter sections is
substantially unchanged by the transfer device 200, such that the
longitudinal axis of each filter section remains substantially
parallel to the first and second axes.
[0073] The transfer device 200 is arranged to receive the plurality
of filter sections directly from the filter forming device 100.
Filter sections are in this way transferred automatically from the
filter forming device 100 to the transfer device 200. Similarly,
the filter wrapping device 300 200 is arranged to receive the
plurality of filter sections directly from the transfer device 200.
Filter sections are in this way transferred automatically from the
transfer device 200 to the filter wrapping device 300. As such, the
apparatus provides a continuous assembly line. Filter sections are
transferred automatically and, according to examples described
herein, mechanically, from the filter forming device 100 to the
filter wrapping device 300. The apparatus does not require a hopper
positioned between the filter forming device and the filter
wrapping device in order to accumulate a plurality of filter
sections for collection by the filter wrapping device.
[0074] Referring to FIG. 5, the transfer device 200 comprises a
plurality of receptacles 210 each configured to receive one or more
filter sections in a linear direction and to provide rotational
movement to the one or more filter sections. In some embodiments,
each receptacle 210 receives one filter section. Alternatively,
each receptacle 210 may receive two or more filter sections. The
receptacles 210 are formed on a plurality of carrier arms 220,
which are pivotably mounted on a rotating transfer support 230. The
transfer support 230 rotates about an axis which is substantially
perpendicular to the first longitudinal axis. The axis of rotation
of the transfer support 230 is inclined with respect to the
horizontal. Alternatively, the axis of rotation is substantially
horizontal and the transfer support 230 rotates in a vertical
plane.
[0075] The receptacle 210 holds the filter section by means of
suction, which can be turned off such that the filter section is
deposited. Alternatively, the filter section is held by means of a
releasable clamp, or a trough which is tilted or overturned to
deposit the filter section. The carrier arms 220 are pivotably
mounted such that the filter sections carried by the plurality of
receptacles 210 are held substantially parallel to the first
longitudinal axis throughout the transfer motion.
[0076] In an alternative embodiment, the plurality of receptacles,
rather than being formed on a plurality of carrier arms 220, are
formed on an outer surface of a rotating collection drum. The
collection drum rotates about a second axis parallel to the first
longitudinal axis of the filter forming device 200. The receptacles
are arranged to receive one or more filter sections moving
longitudinally from the filter forming device 200. The receptacles
are formed by a plurality of recesses on the outer surface of the
collection drum. The recesses forming the receptacles may have a
fluted profile, being wider at an end proximate to the filter
forming device 200.
[0077] The collection drum, or other filter transfer devices
described herein, may be formed as part of the filter forming
device 100 or as part of the filter wrapping device 300. In some
examples, the collection drum is arranged to receive the plurality
of filter sections moving longitudinally from the garniture of the
shaping device.
[0078] In some embodiments, the transfer device 200 further
comprises a transfer drum 240 which rotates about a third axis
parallel to the first longitudinal axis of the filter forming
device 200. The transfer drum 240 comprises a plurality of recesses
241 formed in an outer surface thereof. The plurality of
receptacles 210 deposit the filter sections into the recesses 241
of the transfer drum 240, wherein the filter sections are conveyed
by rotational movement around the third axis of the transfer drum
240. The filter sections are held in the recesses 241 of the
transfer drum 240 by suction means. Alternatively, the filter
sections are held on the outer surface of the transfer drum 240 by
an arrangement of pins.
[0079] The plurality of filter sections are passed from the
transfer drum 240 to the wrapping drum of the filter wrapping
device, wherein the plurality of tipping paper or other material
blanks are affixed and rolled around the filter sections. In some
embodiments, the blanks are affixed to the filter sections whilst
they are held in the recesses 241 of the transfer drum 240, and the
filter sections with blanks attached are passed to the wrapping
drum, wherein the blanks are rolled around the filter sections by
the rolling element. Alternatively, the blanks are affixed to the
filter sections whilst they are held in the recesses 241 of the
transfer drum 240, and the blanks are rolled around the filter
sections by exerting pressure between the transfer drum 240 and the
rolling element.
[0080] The transfer device 200 is configured to translate linear
movement to rotational movement, such that the plurality of filter
sections can be transferred directly from the filter forming device
100 to the filter wrapping device 300.
[0081] The outer wrapping material 40, e.g. tipping paper, wrapped
around the filter section is suitable for holding the filtration
material in a compressed form. The filtration material can, for
instance, recover from the compression applied by the filter
forming device to impress the surface relief pattern into the
filter section, after the filter section exits the filter forming
device 100. Heating means applied to the plasticiser and cellulose
acetate may be insufficient to cause the filtration material to
harden fast enough to stop recovery expansion of the filtration
material. The plug wrap, if present, may have insufficient tensile
strength to resist the recovery expansion of the filtration
material.
[0082] The compression applied by the garniture 110 can lead to
recovery expansion of the filtration material upon exiting the
filter forming device 100. In addition, the further compression
applied by shaping device can lead to recovery expansion of the
filtration material upon exiting the filter forming device 100. In
particular, the expansion of the filtration material may affect the
surface relief applied to the outer surface of the filter section.
The pattern, e.g. longitudinally extending grooves, applied to the
outer surface of the filter section may be reduced in depth or
removed completely by expansion of the filtration material.
[0083] The covering layer of sheet material applied to the
compressed filter section can at least partially alleviate the
problem recovery expansion of the filtration material, for instance
substantially maintaining the filter section in a compressed form.
By directly and automatically transferring the plurality of filter
sections from the filter forming device to the filter wrapping
device using the filter transfer device, the invention provides a
method in which the filter section can be wrapped before recovery
expansion of the filtration material can take place. For instance,
wrapping the sheet material around the filter section having the
surface relief pattern can take place before the surface relief
pattern is substantially lost by elastic expansion of the filter
section.
[0084] The compressed filter section has a first outer
circumference upon exiting the filter forming device 100, defined
by the largest features, e.g. the ridges, on the outer surface
thereof. The first outer circumference of the filter section is
equivalent to the circumference of the smallest circle which can be
drawn around the filter cross-section. The filter wrapping device
is configured to wrap the covering layer of tipping paper tightly
around the filter section, and forms a cylinder with a
circumference substantially the same as the first outer
circumference. The tensile strength of the tipping paper restricts
the filter section from expanding to have a circumference which is
larger than the first outer circumference.
[0085] The compressed filter section has a first cross sectional
area upon exiting the filter forming device 100. The tensile
strength of the tipping paper restricts the filter section from
expanding to have a cross sectional area which is larger or at
least substantially larger than the first cross sectional area.
[0086] The process of elastic recovery of the filtration material
is not instantaneous and happens gradually upon exit of the filter
section from the filter forming device 100. The invention provides
a method and apparatus for transferring the filter section from the
filter forming device 100 to the filter wrapping device 300, such
that the time for elastic recovery to occur is reduced and the
extent of expansion of the filtration material is reduced. The time
between forming a filter section having a surface relief pattern
with the filter forming device and wrapping a sheet material around
the filter section having the surface relief pattern with the
filter wrapping device can be substantially minimised by the
present invention. The time can, for instance, less than 2 minutes,
1 minute, 30 seconds, 20 seconds, 10 seconds, 2 seconds or 1
second.
[0087] The present invention therefore provides for an expedient
transfer between the filter forming device 100 and the filter
wrapping device 300 such that a covering layer of sheet material,
e.g. tipping paper, can be wrapped around the filter section before
elastic recovery of the filtration material takes place. An amount
of time between compression of the filter section by the filter
forming device and wrapping of the filter section with tipping
paper by the filter wrapping device can be reduced and/or
minimised. The invention therefore reduces and/or minimises the
extent of recovery expansion of the filtration material which can
occur in the plurality of filter sections.
[0088] FIG. 6 is a schematic flow diagram showing an exemplary
method of manufacture. At step S100 a filter section is formed with
a filter forming device. The filter section is formed with a
surface relief pattern on an outer surface. The filter section may
be formed by forming a cylinder of filtration material, which may
be shaped by a shaping device to have the surface relief pattern,
and dividing the cylinder of filtration material to form a
plurality of filter sections. Alternatively, the cylinder of
filtration material may be divided into a plurality of filter
sections, which are shaped by the shaping device.
[0089] The cylinder of filtration material is formed by passing
filtration material through at least one garniture. The shaping
device provides the surface relief pattern by passing the cylinder
of filtration material through at least one garniture.
Alternatively, the cylinder of filtration material may be wrapped
with a plug wrap having one or more weakened areas. The weakened
areas are formed by embossing, crimping or otherwise weakening the
plug wrap prior to wrapping around the filter rod. The weakened
areas of the plug wrap allow for a faster rate of expansion, such
that the surface relief pattern is formed.
[0090] The surface relief pattern may comprise a plurality of
longitudinally extending grooves.
[0091] At step S200 the filter section is transferred from the
filter forming device to a filter wrapping device. The filter
section is transferred using a filter transfer device. The filter
transfer device, in one example, receives the filter section moving
linearly along a longitudinal axis of the filter forming device.
Transferring the filter section to the filter wrapping device
comprises translating linear movement of the filter section into
rotational movement. The transfer device is arranged to translate
linear movement of the filter section along the longitudinal axis
of the filter forming device into rotational movement about a
second axis parallel to the longitudinal axis. The filter section
is provided to the filter wrapping device moving rotationally about
the second axis. The filter section is held parallel to the
longitudinal axis of the filter forming device by the filter
transfer device.
[0092] At step S300 the filter section is wrapped with a sheet
material. The sheet material is wrapped around the filter section
with the filter wrapping device. A blank of the sheet material is
affixed to the filter section by the filter wrapping device. The
blank may be attached to a plurality of filter sections. The blank
may also be attached to one or more tobacco rods. The blank is
wrapped around the filter section by rolling the filter section
with the blank of sheet material attached.
[0093] FIG. 7 shows a second exemplary smoking article 50, which
may be manufactured using the apparatus or method described herein.
The smoking article has an indexing mechanism formed by ridges in a
filter section 30. This smoking article 50 is illustrated by
example only, and the apparatus and method may be used in the
manufacture of different types of smoking article.
[0094] Features other than those described hereinbelow are the same
as those described with respect to FIG. 1 and like numerals refer
to like parts.
[0095] The smoking article 50 includes an outer wrapping material
40 at least a part of which is configured to be movable relative to
the filter section 30. The filter section 30 is located adjacent to
the tobacco rod 20, and the smoking article 50 also comprises a
mouth end filter section 51 affixed to the outer wrapping material
40 . In another embodiment, part of the outer wrapping material 40
affixed to the filter section 30 and a part movable relative to the
filter section 30 may be separably connected, e.g. by a perforated
region of the sheet material 40.
[0096] The relative rotation between the outer wrapping material 40
and the filter section 30 can control a property of the smoking
article 10, e.g. ventilation. The smoking article 50 comprises a
control mechanism in the form of an indexing mechanism 52,
configured to control rotation between the filter section 30 and
outer wrapping material 40. The indexing mechanism 52 comprises an
indexing feature 53 on the filter section which can be engaged by
an engaging feature 54 on the outer wrapping material 40. The outer
wrapping material 40 is rotatable relative to the filter section 30
into a plurality of pre-determined indexed rotational positions.
The indexed positions are narrowly spaced, providing for
incremental step-wise movement.
[0097] The indexing feature 53 is formed by the plurality of
depressions forming a surface relief pattern on the outer surface
of the filter section 30. In particular, the indexing feature 53
comprises a plurality of elongate grooves, separated by ridges,
which extend substantially longitudinally. The ridge between
adjacent depressions defines a point of maximum resistance to
movement of the engaging feature 54 between the adjacent
depressions. The ridge profile is configured to provide for a sound
when the filter section 30 and covering layer 40 are rotated
relative to each other, providing clear audible feedback.
[0098] The indexing grooves and ridges preferably extend around the
whole circumference of the filter section 30, or alternatively,
extend around only a part of the circumference of the filter
section 30. The indexing grooves and ridges may extend over the
whole length or only a part of the length of the filter section 30,
and in the present example are illustrated as only extending over
part of the length of the filter section 30.
[0099] The engaging feature 54 comprises one or more protrusions
extending radially inwardly 30 from the inner surface of the outer
wrapping material 40. The protrusion is configured to engage in the
grooves of the indexing feature 53 to control relative rotation of
the outer wrapping material 40 and filter section 30. The
protrusion is formed by a folded paper pawl affixed to the inner
surface of the outer wrapping material 40. Alternatively, the
protrusion may be formed by a dot of raised ink, dot of glue, by an
indent, by an embossing, or by any other suitable means to engage
with the indexing feature. The indexing feature 53 is resiliently
deformable to allow the protruding feature 54 to releasable engage
therewith. Application of a rotational force above a threshold
level causes resilient deformation of the indexing feature 53,
providing for rotation to the next indexed position where the
protruding feature 54 engages.
[0100] The continuous length of outer wrapping material provided by
the sheet material supply may have a plurality of paper pawls
affixed to an outward facing surface, which are arranged to form
the engaging feature of the indexing mechanism 52. Alternatively,
the outward facing surface of the outer wrapping material may
comprise one or more protrusions formed by a dot of raised ink, dot
of glue, by an indent, by an embossing, or by any other suitable
means to engage with the indexing feature. The continuous length of
outer wrapping material may further be provided with a pattern of
perforations, forming a plurality of separably connected areas of
outer wrapping material.
[0101] Rotation of the outer wrapping material 40 may be
accompanied with an audible sound, e.g. a click, at each
pre-determined position. The indexing mechanism 52 functions to
resist rotation between the filter section 30 and the outer
wrapping material 40, unless sufficient force is applied and the
parts rotate to the next indexed position. The indexing mechanism
52 provides feedback to a user that the parts have been rotated,
preferably in the form of touch in the indexing movement and/or
sound as each indexing position is engaged.
[0102] An exemplary smoking article which may be manufactured by
the method of the present invention can be found in WO 2012/123723
or WO 2013/024623, the contents of which are hereby expressly
incorporated by reference herein in their entirety.
[0103] Filter section 30 is provided with improved surface relief
on an outer surface thereof.
[0104] Any feature of any embodiment described herein can be used
in combination with any other feature of any other embodiment
described herein.
[0105] 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 a superior method and apparatus for manufacturing a
filter for a smoking article. 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.
* * * * *