U.S. patent application number 12/525515 was filed with the patent office on 2010-10-28 for smoking article with closed end and methods and apparatus for manufacture thereof.
Invention is credited to Andrew Jonathan Bray, Karl Kaljura.
Application Number | 20100269839 12/525515 |
Document ID | / |
Family ID | 38925637 |
Filed Date | 2010-10-28 |
United States Patent
Application |
20100269839 |
Kind Code |
A1 |
Kaljura; Karl ; et
al. |
October 28, 2010 |
Smoking article with closed end and methods and apparatus for
manufacture thereof
Abstract
A method of making a smoking article comprises providing a folly
or partially fabricated smoking article comprising at least a
tobacco rod of tobacco wrapped in cigarette paper; adhering a
foldable paper to the cigarette paper such that the foldable paper
encircles the tobacco rod and overhangs the cigarette paper at an
end of the tobacco rod that is intended to be lit; and folding the
overhanging foldable paper to substantially cover the tobacco at
the end of the tobacco rod. Various techniques can be employed to
apply different lengths of foldable paper to the tobacco rod and to
achieve different folding patterns. The folded paper may be
inverted by pressing inwardly with a pin or rod after folding to
produce a more permanent fold.
Inventors: |
Kaljura; Karl; (Southampton,
GB) ; Bray; Andrew Jonathan; (Southampton,
GB) |
Correspondence
Address: |
CHADBOURNE & PARKE LLP
30 ROCKEFELLER PLAZA
NEW YORK
NY
10112
US
|
Family ID: |
38925637 |
Appl. No.: |
12/525515 |
Filed: |
November 1, 2007 |
PCT Filed: |
November 1, 2007 |
PCT NO: |
PCT/GB07/04175 |
371 Date: |
June 21, 2010 |
Current U.S.
Class: |
131/58 ;
131/365 |
Current CPC
Class: |
A24D 1/006 20130101;
A24C 5/60 20130101 |
Class at
Publication: |
131/58 ;
131/365 |
International
Class: |
A24C 1/26 20060101
A24C001/26; A24D 1/02 20060101 A24D001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 14, 2006 |
GB |
0622687.2 |
Feb 27, 2007 |
GB |
0703785.6 |
Claims
1. A method of making a smoking article, comprising: providing a
fully or partially fabricated smoking article comprising at least a
tobacco rod of tobacco wrapped in cigarette paper; adhering a
foldable paper to the cigarette paper such that the foldable paper
encircles the tobacco rod and overhangs the cigarette paper at an
end of the tobacco rod that is intended to be lit; and folding the
overhanging foldable paper to substantially cover the tobacco at
the end of the tobacco rod.
2. The method according to claim 1, wherein the foldable paper is
adhered to the outside of the cigarette paper.
3. The method according to claim 1, wherein the foldable paper is a
porous paper.
4. The method according to claim 3, wherein the foldable paper has
a porosity greater than 3,000 CU.
5. The method according to claim 3, wherein the foldable paper is
porous plug wrap paper.
6. The method according to claim 1, wherein the foldable paper is
embossed with one or more crease lines along which the overhanging
foldable paper is folded.
7. The method according to claim 1, further comprising, before
adhering the foldable paper to the cigarette paper, embossing the
foldable paper with one or more crease lines along which the
overhanging foldable paper is to be folded.
8. The method according to claim 1, wherein the foldable paper
encircling the tobacco rod extends over only part of the length of
the tobacco rod.
9. The method according to claim 1, wherein the foldable paper
encircling the tobacco rod extends over substantially the whole
length of the tobacco rod.
10. The method according to claim 1, wherein adhering the foldable
paper to the cigarette paper comprises: applying adhesive to the
foldable paper, bringing the smoking article into contact with the
foldable paper such that an edge of the foldable paper adheres to
the cigarette paper; and carrying the smoking article in a vacuum
flute on the outer surface of a rotating drum, the smoking article
arranged with its longitudinal axis parallel to the rotation axis
of the drum, so as to bring the smoking article into contact with a
curved static plate spaced apart from the drum by a distance less
than the diameter of the smoking article, contact with the plate
causing the smoking article to rotate about its own longitudinal
axis so that it rolls over the plate as the drum rotates, the
rolling causing the foldable paper to wrap around the smoking
article.
11. The method according to claim 10, wherein the foldable paper is
shaped along an edge such that the overhanging foldable paper has
an edge profile that gives a reduced amount of overlapped paper
after folding compared to a straight edge.
12. The method according to claim 9, wherein adhering the foldable
paper to the cigarette paper comprises: arranging the smoking
article in a sequence of smoking articles arranged end to end but
spaced apart by a distance equal to the desired length of the
overhanging foldable paper; feeding the sequence of smoking
articles onto a continuous length of foldable paper, the foldable
paper having a width at least equal to the circumference of the
smoking articles; wrapping the foldable paper around the smoking
articles to encircle the tobacco rods, and adhering it in place;
and cutting through the foldable paper flush to an end of each
smoking article, to separate the tobacco rods and form the
overhanging foldable paper.
13. The method according to claim 9, wherein adhering the foldable
paper to the cigarette paper comprises: arranging the smoking
article in a sequence of smoking articles arranged end to end in
pairs where the articles in each pair abut at their adjacent ends
and the pairs are spaced apart by a distance equal to twice the
desired length of the overhanging foldable paper; feeding the
sequence of smoking articles onto a continuous length of foldable
paper, the foldable paper having a width at least equal to the
circumference of the smoking articles; wrapping the foldable paper
around the smoking articles to encircle the tobacco rods, and
adhering it in place; and cutting through the foldable paper where
the smoking articles in each pair abut and also at the midpoint of
the spaces between the pairs, to separate the smoking articles and
form the overhanging foldable paper.
14. The method according to claim 1, wherein folding the
overhanging foldable paper comprises: carrying the smoking article
in a vacuum flute on the outer surface of one or more rotating
drums so as to bring the overhanging foldable paper into contact
with one or more folding devices that bend the overhanging foldable
paper inwards over the tobacco at the end of the tobacco rod.
15. The method according to claim 14, wherein the one or more
folding devices comprise a reciprocating tucker with a width less
than the diameter of the smoking article that extends partially
over the end of the tobacco rod flush with the tobacco therein to
create a first fold and then retracts, a fixed tucker with a width
less than the diameter of the tobacco rod and a surface that is
flush with the tobacco against which the end of the tobacco rod
passes to create a second fold opposite the first fold, and a pair
of static plough folders providing surfaces flush with the tobacco
and having oppositely disposed converging edges, against which the
end of tobacco rod passes to form third and fourth folds opposite
one another and orthogonal to the first and second folds.
16. The method according to claim 14, wherein the one or more
folding devices comprise a curved static plate spaced apart from
the rotating drum by a distance less than the diameter of the
smoking article, contact with the plate causing the smoking article
to rotate about its own longitudinal axis so that it rolls over the
plate as the drum rotates, and a plough folder fixed to the plate
and comprising a surface flush with the end of the tobacco rod that
has an edge that converges towards the drum in the direction of
rotation of the drum such that as the smoking article rolls over
the plate the end of the tobacco rod passes against the surface and
the overhanging foldable paper is engaged by the converging edge
and is gradually folded inwards over the tobacco in a continuous
fold.
17. The method according to claim 14, wherein the one or more
folding devices comprise a curved static plate spaced apart from
the rotating drum by a distance less than the diameter of the
smoking article, contact with the plate causing the smoking article
to rotate about its own longitudinal axis so that it rolls over the
plate as the drum rotates, and a sequence of teeth extending from
the plate towards the drum and having surfaces flush with the end
of the tobacco rod, each tooth engaging a part of the overhanging
foldable paper and creating a fold as the smoking article rolls
over the plate, each fold overlapping the previous fold.
18. The method according to claim 14, wherein the one or more
folding devices comprise a curved static plate spaced apart from
the rotating drum by a distance less than the diameter of the
smoking article, contact with the plate causing the smoking article
to rotate about its own longitudinal axis so that it rolls over the
plate as the drum rotates, and a rotatable cam associated with each
vacuum flute on the rotating drum, each cam having a surface flush
with the end of the tobacco rod and configured to sweep across the
end of the tobacco rod as the smoking article rolls over the plate,
the edge of the cam pushing against the overhanging foldable paper
to fold it inwards over the tobacco.
19. The method according to claim 18, wherein the cam has a smooth
edge that creates a continuous fold.
20. The method according to claim 18, wherein the cam has a toothed
edge that creates a series of overlapping folds.
21. The method according to claim 14, wherein the one or more
folding devices comprises a pair of adjacent rotatable surfaces
flush with the end of the tobacco rod that sweep outwardly over the
end of the tobacco rod from the rear of the smoking article as it
is carried by the rotating-drum to create first and second adjacent
folds, and a static tucker having a surface flush with the end of
the tobacco rod against which the end of the tobacco rod passes to
create a third fold.
22. The method according to claim 14, wherein the one or more
folding devices comprise a curved static plate spaced apart from
the rotating drum by a distance less than the diameter of the
smoking article, contact with the plate causing the smoking article
to rotate about its own longitudinal axis so that it rolls over the
plate as the drum rotates, and a rotating threaded screw positioned
with its axis of rotation orthogonal to the axis of rotation of the
rotating drum and substantially tangential to the perimeter of the
drum, and the threaded surface flush with the end of the tobacco
rod such that the screw thread engages with the overhanging
foldable paper as the smoking article rolls across the plate and
the rotation of the screw folds the paper inwards over the
tobacco.
23. The method according to claim 14, wherein the one or more
folding devices comprise a protrusion in a vacuum flute of a first
rotating drum that pushes part of the overhanging foldable paper
inwards over the tobacco when the smoking article enters the vacuum
flute to create a first fold, a further protrusion in a vacuum
flute of a second, adjacent, rotating drum to which the smoking
article is transferred from the first drum, the further protrusion
pushing part of the overhanging foldable paper inwards over the
tobacco when the smoking article enters the flute to create a
second fold opposite the first fold, and a pair of static plough
folders providing oppositely disposed surfaces flush with the end
of the tobacco rod and having converging edges, against which the
end of tobacco rod passes to create third and fourth folds opposite
one another and orthogonal to the first and second folds.
24. The method according to claim 14, wherein the one or more
folding devices comprise a protrusion in a vacuum flute of a first
rotating drum that pushes part of the overhanging foldable paper
inwards over the tobacco when the smoking article enters the vacuum
flute to create a first fold, a further protrusion in a vacuum
flute of a second, adjacent, rotating drum to which the smoking
article is transferred from the first drum, the further protrusion
pushing part of the overhanging foldable paper inwards over the
tobacco when the smoking article enters the flute to create a
second fold opposite the first fold, and a pair of reciprocating
folders that sweep inwardly over the end of the tobacco rod and
then retract to create third and fourth folds opposite one another
and orthogonal to the first and second folds.
25. The method according to claim 14, wherein the one or more
folding devices comprise a protrusion in a vacuum flute of a first
rotating drum that pushes part of the overhanging foldable paper
inwards over the tobacco when the smoking article enters the vacuum
flute to create a first fold, a further protrusion in a vacuum
flute of a second, adjacent, rotating drum to which the smoking
article is transferred from the first drum, the further protrusion
pushing part of the overhanging foldable paper inwards over the
tobacco when the smoking article enters the flute to create a
second fold opposite the first fold, a fixed folder disposed at the
side of a vacuum flute of a third, adjacent, rotating drum to which
the smoking article is transferred from the second drum which
engages with the overhanging foldable paper as the smoking article
enters the vacuum flute and pushes the paper inwards over the
tobacco to create a third fold orthogonal to the first and second
folds, and a further fixed folder disposed at the side of a vacuum
flute of a fourth, adjacent, rotating drum to which the smoking
article is transferred from the third drum which engages with the
overhanging foldable paper as the smoking article enters the vacuum
flute and pushes the paper inwards over the tobacco to create a
fourth fold opposite to the third fold.
26. The method according to claim 23, wherein in which one or both
of the said protrusion and the further protrusion are configured to
move between an extended position for effecting the first or second
fold as the smoking article enters the vacuum flute, and a
retracted position after the fold is effected in which the
protrusion does not protrude into the flute.
27. The method according to claim 14, wherein the one or more
folding devices comprises a first pair of pincers longitudinally
aligned with a vacuum flute of a first rotating drum, and biased in
an open position to receive the overhanging foldable paper of a
smoking article in the vacuum flute, the pincers operable to close
on the received overhanging foldable paper and push opposite parts
of the paper inwards over the tobacco to create opposite first and
second folds, and a second pair of pincers longitudinally aligned
with a vacuum flute of a second rotating drum, and biased in a open
position to receive the overhanging foldable paper of the smoking
article when transferred to the vacuum flute after folding in the
vacuum flute of the first rotating drum, the pincers operable to
close on the remaining overhanging foldable paper and push the
opposite parts of the paper inwards over the tobacco to create
opposite third and fourth folds orthogonal to the first and second
folds.
28. The method according to claim 14, wherein the one or more
folding devices comprises a first pair of pincers longitudinally
aligned with a vacuum flute of a first rotating drum, and biased in
an open position to receive the overhanging foldable paper of a
smoking article in the vacuum flute, the pincers operable to close
on the received overhanging foldable paper and push opposite parts
of the paper inwards over the tobacco to create opposite first and
second folds, and one or more supplementary folding devices
associated with a second rotating drum arranged to receive the
smoking article after folding with the first drum, and operable to
fold the remaining opposite parts of the paper inwards over the
tobacco to create opposite third and fourth folds orthogonal to the
first and second folds.
29. The method according to claim 1, wherein adhering the foldable
paper to the cigarette paper comprises: applying adhesive to the
foldable paper; bringing the smoking article into contact with the
foldable paper such that an edge of the foldable paper adheres to
the cigarette paper; and introducing the smoking article onto a
lower surface that is spaced apart from an upper surface by a
distance less than the diameter of the smoking article, the upper
surface moving relative to the lower surface along a direction
parallel to the surfaces and orthogonal to the longitudinal axis of
the smoking articles such that contact with the surfaces causes the
smoking article to rotate about its longitudinal axis so that it
rolls over the lower surface as the upper surface moves, the
rolling causing the foldable paper to wrap around the smoking
article.
30. The method according to claim 29, wherein the upper surface
comprises an endless belt rotating around a pair of rollers.
31. The method according to claim 29, wherein folding the
overhanging paper comprises using the rolling of the smoking
article over the lower surface to bring the overhanging foldable
paper into contact with one or more folding devices that bend the
overhanging foldable paper inwards over the tobacco at the end of
the tobacco rod.
32. The method according to claim 31, wherein the one or more
folding devices comprise a series of teeth extending from the lower
surface towards the upper surface and having surfaces flush with
the end of the tobacco rod, each tooth engaging a part of the
overhanging foldable paper and creating a fold as the smoking
article rolls over the lower surface, each fold overlapping the
previous fold.
33. The method according to claim 1, wherein folding the
overhanging foldable paper comprises pushing part of the paper
inwards to create a first fold, pushing a further part of the paper
inwards to create a second fold opposite the first fold, and
trimming off some or all of the remaining, unfolded paper.
34. The method according to claim 1, further comprising, after
folding the overhanging foldable paper, pushing against the end of
the tobacco rod with a pin having a width less than the diameter of
the smoking article to depress the folded paper and cause it to
better maintain its folded position.
35. The method according to claim 1, wherein the foldable paper is
provided with adhesive on all or part of the inner surface of the
overhanging portion, and the method further comprises, after
folding the overhanging paper, pressing against the end of the
tobacco rod to cause the folded paper to become adhered in its
folded position.
36. The method according to claim 35, wherein the adhesive is
heat-activated, and pressing against the end of the tobacco rod
includes applying heat to the end of the tobacco rod.
37. The method according to claim 1, further comprising, if the
smoking article is a partially fabricated smoking article,
attaching a filter unit to the end of the tobacco rod opposite to
the end intended to be lit.
38. The method according to claim 37, wherein the filter unit is
attached to the end of the tobacco rod simultaneously with the
adhering and/or folding of the foldable paper.
39. The method according to claim 1, further comprising, after
folding the overhanging paper: inspecting the folded overhanging
paper for defects; and rejecting a smoking article found to have a
defective folded overhanging paper.
40. The method according to claim 39, wherein the inspecting
comprises: capturing one or more images of the folded overhanging
paper; and comparing the one or more captured images with one or
more stored images of non-defective folded overhanging paper.
41. The method according to claim 40, wherein the one or more
captured images comprise at least one of an end view of the folded
overhanging paper and a side view of the folded overhanging
paper.
42. (canceled)
43. A smoking article comprising: a tobacco rod of tobacco wrapped
in cigarette paper; and a foldable paper adhered to the cigarette
paper such that the foldable paper encircles the tobacco rod and
overhangs the cigarette paper at an end of the tobacco rod that is
intended to be lit, the overhanging foldable paper folded to
substantially cover the tobacco at the end of the tobacco rod.
44. The smoking article according to claim 43, wherein the foldable
paper is adhered to the outside of the cigarette paper.
45. The smoking article according to claim 43, wherein the foldable
paper is a porous paper.
46. The smoking article according to claim 45, wherein the foldable
paper has a porosity of greater than 3,000 CU.
47. The smoking article according to claim 45, wherein the foldable
paper is porous plug wrap paper.
48. The smoking article according to claim 43, wherein the foldable
paper is embossed with one or more crease lines along which the
overhanging foldable paper is folded.
49. The smoking article according to claim 43, wherein the foldable
paper encircling the tobacco rod extends over only part of the
length of the tobacco rod.
50. The smoking article according to claim 43, wherein the foldable
paper encircling the tobacco rod extends over substantially the
whole length of the tobacco rod.
51. The smoking article according to claim 43, wherein the foldable
paper is shaped along an edge such that the overhanging foldable
paper has an edge profile that gives a reduced amount of overlapped
paper after folding compared to a straight edge.
52. The smoking article according to claim 43, wherein the
overhanging foldable paper is folded with a first fold, a second
fold opposite the first fold, a third fold orthogonal to the first
and second folds, and a fourth fold opposite the third fold.
53. The smoking article according to claim 43, wherein the
overhanging foldable paper is folded with a plurality of folds,
each fold overlapping the adjacent fold.
54. The smoking article according to claim 43, further comprising a
filter unit attached to the end of the tobacco rod opposite to the
end intended to be lit.
55. An apparatus for making a smoking article comprising: a first
sub-apparatus operable to receive a fully or partially fabricated
smoking article comprising at least a rod of tobacco wrapped in
cigarette paper and to adhere a foldable paper to the cigarette
paper such that the foldable paper encircles the tobacco rod and
overhangs the cigarette paper at an end of the tobacco rod that is
intended to be lit; and a second sub-apparatus operable to receive
a smoking article with an overhanging foldable paper produced by
the first sub-apparatus and to fold the overhanging foldable paper
to substantially cover the tobacco at the end of the tobacco
rod.
56. The apparatus according to claim 55, wherein the first
sub-apparatus is operable to adhere the foldable paper to the
outside of the cigarette paper.
57. The apparatus according to claim 55, further comprising one or
more embossing devices through which the foldable paper is passed
before being supplied to the first sub-apparatus, the one or more
embossing devices operable to emboss the foldable paper with one or
more crease lines along which the overhanging foldable paper is to
be folded by the second sub-apparatus.
58. The apparatus according to claim 55, wherein the first
sub-apparatus is configured to adhere the foldable paper to the
cigarette paper such that the foldable paper encircling the tobacco
rod extends over only part of the length of the tobacco rod.
59. The apparatus according to claim 55, wherein the first
sub-apparatus is configured to adhere the foldable paper to the
cigarette paper such that the foldable paper encircling the tobacco
rod extends over substantially the whole length of the tobacco
rod.
60. The apparatus according to claim 55, wherein the first
sub-apparatus comprises: a dispenser for dispensing foldable paper
from a continuous roll; an adhesive applicator for applying
adhesive to foldable paper dispensed from the roll, the adhesive
distributed appropriately for securing the foldable paper to a
cigarette paper such that it encircles a tobacco rod; a vacuum
cutting drum rotatable about a first axis of rotation and having a
plurality of blades extending radially from its circumference,
rotation of the vacuum cutting drum engaging the blades in turn
with the dispensed foldable paper to which adhesive has been
applied to cut the dispensed foldable paper into individual
foldable papers, the vacuum cutting drum further having suction
holes through which a vacuum is applied to hold the individual
foldable papers on the surface of the vacuum cutting drum with the
adhesive facing outwards; a first rotatable drum rotatable about a
second axis of rotation parallel to the first axis of rotation and
having around its circumference a plurality of vacuum flutes for
receiving smoking articles with their longitudinal axes parallel to
the second axis of rotation, the first rotatable drum positioned
with respect to the vacuum cutting drum such that a smoking article
carried in a flute of the first rotatable drum contacts an
individual foldable paper on the vacuum cutting drum such that an
edge of the foldable paper adheres to the smoking article; a second
rotatable drum rotatable about a third axis of rotation parallel to
the first axis of rotation and having around its circumference a
plurality of vacuum flutes for receiving smoking articles with
their longitudinal axes parallel to the third axis of rotation, the
second rotatable drum positioned with respect to the first
rotatable drum such that a smoking article with an adhered foldable
paper carried in a flute of the first rotatable drum can be passed
to a flute on the second rotatable drum; and a curved static plate
spaced apart from the second rotatable drum by a distance less than
the diameter of the smoking article, such that rotation of the
second rotatable drum brings a smoking article with an adhered
foldable paper carried in a flute of the second rotatable drum into
contact with the curved static plate, contact with the plate
causing the smoking article to rotate about its own longitudinal
axis so that it rolls over the plate as the drum rotates, the
rolling causing the foldable paper to wrap around the smoking
article.
61. The apparatus according to claim 59, wherein the first
sub-apparatus comprises: a dispenser for dispensing foldable paper
from a continuous roll, the foldable paper having a width at least
equal to the circumference of a smoking article; an adhesive
applicator for applying adhesive to foldable paper dispensed from
the roll, the adhesive distributed appropriately for securing the
foldable paper to a cigarette paper such that it encircles a
tobacco rod; a smoking article feeder operable to feed onto a
continuous length of foldable paper dispensed from the roll a
sequence of smoking articles arranged end to end but spaced apart
by a distance equal to the desired length of the overhanging
foldable paper; a tube into which the dispensed foldable paper with
applied adhesive and the sequence of smoking articles thereon may
be fed, the tube causing the foldable paper to wrap around the
smoking articles to encircle the tobacco rods and adhere in place;
and a cutter arranged after the tube and operable to cut through
the foldable paper as it emerges from the tube at positions flush
to an end of each smoking article, to separate the smoking articles
and form the overhanging foldable paper.
62. The apparatus according to claim 59, wherein the first
sub-apparatus comprises: a dispenser for dispensing foldable paper
from a continuous roll, the foldable paper having a width at least
equal to the circumference of a smoking article; an adhesive
applicator for applying adhesive to foldable paper dispensed from
the roll, the adhesive distributed appropriately for securing the
foldable paper to a cigarette paper such that it encircles a
tobacco rod; a smoking article feeder operable to feed onto a
continuous length of foldable paper dispensed from the roll a
sequence of smoking articles arranged end to end in pairs such that
the articles in each pair abut at their adjacent ends and the pairs
are spaced apart by a distance equal to twice the desired length of
the overhanging foldable paper; a tube into which the dispensed
foldable paper with applied adhesive and the sequence of
smoking-articles thereon may be fed, the tube causing the foldable
paper to wrap around the smoking articles to encircle the tobacco
rods and adhere in place; and a cutter arranged after the tube and
operable to cut through the foldable paper as it emerges from the
tube at positions where the smoking articles in each pair abut and
also at the midpoint of the spaces between the pairs, to separate
the smoking articles and form the overhanging foldable paper.
63. The apparatus according to claim 55, wherein the second
sub-apparatus comprises: one or more adjacent rotatable drums
rotatable about parallel axes of rotation, each drum having around
its circumference a plurality of vacuum flutes for receiving
smoking articles with their longitudinal axes parallel to the axis
of rotation of the drum; and one or more folding devices for
folding the overhanging foldable paper, and positioned such that
the overhanging foldable paper of a smoking article carried in a
vacuum flute of the one or more drums can be brought into contact
with the one or more folding devices to bend the overhanging
foldable paper inwards over the tobacco at the end of the tobacco
rod.
64. The apparatus according to claim 63, wherein the one or more
folding devices comprise a reciprocating tucker with a width less
than the diameter of the smoking article that extends partially
over the end of the tobacco rod flush with the tobacco therein to
create a first fold and then retracts, a fixed tucker with a width
less than the diameter of the tobacco rod and a surface that is
flush with the tobacco against which the end of the tobacco rod
passes to create a second fold opposite the first fold, and a pair
of static plough folders providing surfaces flush with the tobacco
and having oppositely disposed converging edges, against which the
end of tobacco rod passes to form third and fourth folds opposite
one another and orthogonal to the first and second folds.
65. The apparatus according to claim 63, wherein the one or more
folding devices comprise a curved static plate, spaced apart from
one of the one or more rotatable drums by a distance less than the
diameter of the smoking article, contact with the plate causing the
smoking article to rotate about its own longitudinal axis so that
it rolls over the plate as the drum rotates, and a plough folder
fixed to the plate and comprising a surface flush with the end of
the tobacco rod that has an edge that converges towards the drum in
the direction of rotation of the drum such that as the smoking
article rolls over the plate the end of the tobacco rod passes
against the surface and the overhanging foldable paper is engaged
by the converging edge and is gradually folded inwards over the
tobacco in a continuous fold.
66. The apparatus according to claim 63, wherein the one or more
folding devices comprise a curved static plate spaced apart from
one of the one or more rotatable drums by a distance less than the
diameter of the smoking article, contact with the plate causing the
smoking article to rotate about its own longitudinal axis so that
it rolls over the plate as the drum rotates, and a sequence of
teeth extending from the plate towards the drum and having surfaces
flush with the end of the tobacco rod, each tooth engaging a part
of the overhanging foldable paper and creating a fold as the
smoking article rolls over the plate, each fold overlapping the
previous fold.
67. The apparatus according to claim 63, wherein the one or more
folding devices comprise a curved static plate spaced apart from
one of the one or more rotatable drums by a distance less than the
diameter of the smoking article, contact with the plate causing the
smoking article to rotate about its own longitudinal axis so that
it rolls over the plate as the drum rotates, and a rotatable cam
associated with each vacuum flute on the rotatable drum, each cam
having a surface flush with the end of the tobacco rod and
configured to sweep across the end of the tobacco rod as the
smoking article rolls over the plate, the edge of the cam pushing
against the overhanging foldable paper to fold it inwards over the
tobacco.
68. The apparatus according to claim 67, wherein the cam has a
smooth edge that creates a continuous fold.
69. The apparatus according to claim 67, wherein the cam has a
toothed edge that creates a series of overlapping folds.
70. The apparatus according to claim 63, wherein the one or more
folding devices comprise a pair of adjacent rotatable surfaces
flush with the end of the tobacco rod that sweep outwardly over the
end of the tobacco rod from the rear of the smoking article as it
is carried by the rotatable drum to create first and second
adjacent folds, and a static tucker having a surface flush with the
end of the tobacco rod against which the end of the tobacco rod
passes to create a third fold.
71. The apparatus according to claim 63, wherein the one or more
folding devices comprise a curved static plate spaced apart from
one of the one or more rotatable drums by a distance less than the
diameter of the smoking article, contact with the plate causing the
smoking article to rotate about its own longitudinal axis so that
it rolls over the plate as the drum rotates, and a rotatable
threaded screw positioned with its axis of rotation orthogonal to
the axis of rotation of the rotatable drum and substantially
tangential to the perimeter of the drum, and the threaded surface
flush with the end of the tobacco rod such that the screw thread
engages with the overhanging foldable paper as the smoking article
rolls across the plate and the rotation of the screw folds the
paper inwards over the tobacco.
72. The apparatus according to claim 63, wherein the one or more
folding devices comprise protrusions in the vacuum flutes of a
first rotatable drum that push part of the overhanging foldable
paper inwards over the tobacco when a smoking article enters the
vacuum flute to create a first fold, further protrusions in the
vacuum flutes of a second, adjacent, rotatable drum to which a
smoking article may be transferred from the first drum, the further
protrusions pushing part of the overhanging foldable paper inwards
over the tobacco when a smoking article enters the flute to create
a second fold opposite the first fold, and a pair of static plough
folders associated with a third, adjacent, rotatable drum to which
a smoking article may be transferred from the second drum, the
plough folders providing oppositely disposed surfaces flush with
the end of the tobacco rod and having converging edges, against
which the end of a tobacco rod of a smoking article carried by the
third drum passes to create third and fourth folds opposite one
another and orthogonal to the first and second folds.
73. The apparatus according to claim 63, wherein the one or more
folding devices comprise protrusions in a vacuum flutes of a first
rotatable drum that pushes part of the overhanging foldable paper
inwards over the tobacco when the smoking article enters the vacuum
flute to create a first fold, further protrusions in the vacuum
flutes of a second, adjacent, rotatable drum to which a smoking
article may be transferred from the first drum, the further
protrusions pushing part of the overhanging foldable paper inwards
over the tobacco when a smoking article enters the flute to create
a second fold opposite the first fold, and a pair of reciprocating
folders associated with a third, adjacent, rotatable drum to which
a smoking article may be transferred from the second drum, the
folders operable to sweep inwardly over the end of a tobacco rod of
a smoking article carried by the third drum and then retract to
create third and fourth folds opposite one another and orthogonal
to the first and second folds.
74. The apparatus according to claim 72, further comprising a
curved static plate spaced apart from the second rotatable drum by
a distance less than the diameter of a smoking article, contact
with the plate causing a smoking article carried by the second drum
to rotate about its own longitudinal axis by substantially ninety
degrees before being transferred to the third rotatable drum.
75. The apparatus according to claim 63, wherein the one or more
folding devices comprise protrusions in the vacuum flutes of a
first rotatable drum that push part of the overhanging foldable
paper inwards over the tobacco when a smoking article enters the
vacuum flute to create a first fold, further protrusions in the
vacuum flutes of a second, adjacent, rotatable drum to which a
smoking article may be transferred from the first drum, the further
protrusions pushing part of the overhanging foldable paper inwards
over the tobacco when a smoking article enters the flute to create
a second fold opposite the first fold, fixed folders disposed at
the side of each vacuum flute of a third, adjacent, rotatable drum
to which the smoking article is transferred from the second drum
which engages with the overhanging foldable paper as a smoking
article enters the vacuum flute and pushes the paper inwards over
the tobacco to create a third fold orthogonal to the first and
second folds, and further fixed folders disposed at the side of
each vacuum flute of a fourth, adjacent, rotatable drum to which a
smoking article may be transferred from the third drum which
engages with the overhanging foldable paper as the smoking article
enters the vacuum flute and pushes the paper inwards over the
tobacco to create a fourth fold opposite to the third fold.
76. The apparatus according to claim 72, wherein the said
protrusions and/or the further protrusions are configured to move
between an extended position for effecting the first or second fold
as a smoking article enters the vacuum flute, and a retracted
position after the fold is effected in which the protrusion does
not protrude into the flute.
77. The apparatus according to claim 63, wherein the one or more
folding devices comprise first pairs of pincers longitudinally
aligned with each vacuum flute of a first rotatable drum, each
first pair of pincers biased in an open position to receive the
overhanging foldable paper of a smoking article in its associated
vacuum flute, the pincers operable to close on the received
overhanging foldable paper and push opposite parts of the paper
inwards over the tobacco to create opposite first and second folds,
and second pairs of pincers longitudinally aligned with each vacuum
flute of a second rotatable drum, each second pair of pincers
biased in an open position to receive the overhanging foldable
paper of a smoking article when transferred to its associated
vacuum flute after folding in a vacuum flute of the first rotatable
drum, the pincers operable to close on the remaining overhanging
foldable paper and push the opposite parts of the paper inwards
over the tobacco to create opposite third and fourth folds
orthogonal to the first and second folds.
78. The apparatus according to claim 63, wherein the one or more
folding devices comprise first pairs of pincers longitudinally
aligned with each vacuum flute of a first rotatable drum, each
first pair of pincers biased in an open position to receive the
overhanging foldable paper of a smoking article in its associated
vacuum flute, the pincers operable to close on the received
overhanging foldable paper and push opposite parts of the paper
inwards over the tobacco to create opposite first and second folds,
and one or more supplementary folding devices associated with a
second rotatable drum arranged to receive smoking article after
folding with the first rotatable drum, and operable to fold the
remaining opposite parts of the overhanging foldable paper inwards
over the tobacco to create opposite third and fourth folds
orthogonal to the first and second folds.
79. The apparatus according to claim 55, wherein the first
sub-apparatus comprises: a dispenser for dispensing foldable paper;
an adhesive applicator for applying adhesive to the dispensed
foldable paper, the adhesive distributed appropriately for securing
the foldable paper to a cigarette paper such that it encircles a
tobacco rod; a smoking article carrier for bringing a smoking
article in contact with the foldable paper such that an edge of the
foldable paper adheres to the cigarette paper; a lower surface; and
an upper surface spaced apart from the lower surface by a distance
less than the diameter of a smoking article, the upper surface
movable relative to the lower surface along a direction parallel to
the surfaces; wherein a smoking article with an adhered foldable
paper can be introduced onto the lower surface with its
longitudinal axis orthogonal to the direction along which the upper
surface moves, such that contact with the surfaces causes the
smoking article to rotate about its longitudinal axis so that it
rolls over the lower surface as the upper surface moves, the
rolling causing the foldable paper to wrap around the smoking
article.
80. The apparatus according to claim 79, wherein the upper surface
comprises an endless belt rotatable around a pair of rollers.
81. The apparatus according to claim 55, wherein the second
sub-apparatus comprises: a lower surface; an upper surface spaced
apart from the lower surface by a distance less than the diameter
of a smoking article, the upper surface movable relative to the
lower surface along a direction parallel to the surfaces, wherein a
smoking article with an overhanging foldable paper can be
introduced onto the lower surface with its longitudinal axis
orthogonal to the direction along which the upper surface moves,
such that contact with the surfaces causes the smoking article to
rotate about its longitudinal axis so that it rolls over the lower
surface as the upper surface moves; and one or more folding devices
that bend the overhanging foldable paper inwards over the tobacco
at the end of the tobacco rod of a smoking article, the folding
devices positioned such that the rolling of a smoking article over
the lower surface brings the overhanging foldable paper into
contact with the one or more folding devices.
82. The apparatus according to claim 81, wherein the one or more
folding devices comprise a series of teeth extending from the lower
surface towards the upper surface and having surfaces flush with
the end of the tobacco rod, each tooth engaging a part of the
overhanging foldable paper and creating a fold as a smoking article
rolls over the lower surface, each fold overlapping the previous
fold.
83. The apparatus according to claim 55, further comprising a third
sub-apparatus operable to receive a smoking article with a folded
overhanging foldable paper from the second sub-apparatus and to
push a pin having a width less than the diameter of the smoking
article against the folded overhanging foldable paper to depress
the folded paper and cause it to better maintain its folded
position.
84. The apparatus according to claim 83, wherein the third
sub-apparatus comprises: a rotatable drum rotatable about an axis
of rotation and having around its circumference a plurality of
vacuum flutes for receiving smoking articles with their
longitudinal axes parallel to the axis of rotation; a rotatable
plate adjacent to the drum and rotatable about the said axis of
rotation, and having on its surface a plurality of pins equal to
the number of vacuum flutes, the pins extending towards to the
rotatable drum and having a spatial distribution matching that of
the vacuum flutes, the drum and the plate rotatable in the same
direction at the same speed; and a bearing operable to move the
plate towards the drum when both are rotating by a distance that
cause the pins to press into the folded paper at the ends of
smoking articles carried in the vacuum flutes, and to then retract
the plate from the drum.
85. The apparatus according to claim 84, wherein the rotatable
plate comprises a swash plate.
86. The apparatus according to claim 83, wherein the or each pin is
heated so as to activate a heat-activated adhesive on the
overhanging foldable paper when the folded overhanging foldable
paper is depressed.
87. The apparatus according to claim 55, further comprising a third
sub-apparatus operable to receive a smoking article with a folded
overhanging foldable paper from the second sub-apparatus, and to
apply pressure and/or heat to the folded overhanging foldable paper
to activate adhesive on the overhanging foldable paper and cause it
to become adhered in its folded position.
88. The apparatus according to claim 83, wherein the third
sub-apparatus comprises: a rotatable drum rotatable about a first
axis of rotation and having around its circumference a plurality of
vacuum flutes for receiving smoking articles with their
longitudinal axes parallel to the axis of rotation; and a rotatable
disc adjacent to the drum and rotatable about an axis of rotation
orthogonal to the first axis of rotation, and having around its
edge a plurality of spaced apart pins extending radially outwards
by a distance such that a pin directed towards the drum may press
into the folded paper of a smoking article carried in a vacuum
flute, the spacing of the pins and the speed of rotation of the
drum and disc being such as to bring consecutive pins into pressing
contact with consecutive smoking articles carried in the vacuum
flutes.
89. The apparatus according to claim 55, further comprising a
fourth sub-apparatus operable to attach a filter unit to the end of
a tobacco rod of a partially fabricated smoking article, opposite
to the end intended to be lit.
90. The apparatus according to claim 89, wherein the fourth
sub-apparatus is operable to attach the filter unit to the smoking
article simultaneously with the first sub-apparatus adhering a
foldable paper to the smoking article and/or with the
second-sub-apparatus folding the overhanging foldable paper of the
smoking article.
91. The apparatus according to claim 55, further comprising an
inspection system operable to inspect the folded overhanging paper
for defects and reject a smoking article found to have a defective
folded overhanging paper.
92. The apparatus according to claim 91, wherein the inspection
system comprises: one or more cameras operable to capture one or
more images of the folded overhanging paper; a control system
operable to compare the one or more captured images with one or
more stored images of non-defective folded overhanging paper and to
generate a rejection signal if a defective folded overhanging paper
is found; and a rejection mechanism operable to receive the signal
from the control system and remove the smoking article having the
defective folded overhanging paper from the apparatus.
93. The apparatus according to claim 92, wherein the one or more
cameras comprise at least one of a first camera arranged to capture
an end view of the folded overhanging paper and a second camera
arranged to capture a side view of the folded overhanging
paper.
94-96. (canceled)
97. The method according to claim 3, wherein the foldable paper has
a porosity greater than 6,000 CU.
98. The method according to claim 3, wherein the foldable paper has
a porosity greater than 12,000 CU.
99. The method according to claim 3, wherein the foldable paper has
a porosity greater than 24,000 CU.
100. The smoking article of claim 45, wherein the foldable paper
has a porosity greater than 6,000 CU.
101. The smoking article of claim 45, wherein the foldable paper
has a porosity greater than 12,000 CU.
102. The smoking article of claim 45, wherein the foldable paper
has a porosity greater than 24,000 CU.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to smoking articles having
closed ends, and methods and apparatus for making smoking article
having closed ends.
[0002] Manufactured smoking articles such as cigarettes
conventionally comprise a tobacco rod having a wrapping of
cigarette paper, and a filter attached to the tobacco rod by a
tipping paper, although plain cigarettes, lacking a filter, are
also available. In either case, the end of the cigarette which is
intended to be lit is often open, so that the tobacco inside the
cigarette paper is exposed. This allows leakage or spillage of
tobacco from the cigarette, and also allows contaminants and
foreign bodies to enter the tobacco.
[0003] It has been previously proposed to close one or both ends of
a cigarette by folding or otherwise manipulating a portion of the
cigarette paper that extends beyond the tobacco rod. For example,
U.S. Pat. No. 1,164,118 describes a cigarette-making machine that
forms a tube of cigarette paper, closes one end of the tube, fills
the tube with tobacco, and then closes the other end. Both closures
are achieved by components that grip the tube ends and rotate to
twist the paper while the tube is held stationary. U.S. Pat. No.
501,498 describes a machine that wraps cigarette paper around
tobacco, compresses the tobacco from both ends to make paper
overhangs for folding, and then closes each end of the paper using
two tuckers that push the paper over and a conical head that is
inserted into the end of the closed cigarette and rotated to force
the paper inwards and smooth it. The cigarette is held still while
the closure components move. U.S. Pat. No. 903,101 describes a
machine that forms a tube of cigarette paper and closes one end
before filling the tube with tobacco. The closure is effected by a
notched plate that slides over the end of the tube and back again,
while both tube and plate are moving along the longitudinal
direction of the tube. U.S. Pat. No. 3,208,458 describes a machine
that wraps cigarette papers around tobacco, the papers having
scalloped edges. The cigarette is then held still while a series of
three blades spaced 120.degree. apart move in and out against the
ends of the cigarette to fold over the separate flaps of the
scalloped edges of the paper. GB 278,534 describes a cigarette with
the cigarette paper turned inwardly over the end of the wrapped
tobacco to form a tubular extension into the tobacco that partially
covers the tobacco.
[0004] However, these various approaches to closing the end of a
cigarette are not at all recent, and are hence not well-suited to
modern cigarette manufacturing techniques. The present invention
aims to provide closed end cigarettes using methods and apparatus
that are more compatible with current cigarette manufacturing
machinery.
SUMMARY OF THE INVENTION
[0005] Accordingly, a first aspect of the present invention is
directed to a method of making a smoking article, comprising:
providing a fully or partially fabricated smoking article
comprising at least a tobacco rod of tobacco wrapped in cigarette
paper; adhering a foldable paper to the cigarette paper such that
the foldable paper encircles the tobacco rod and overhangs the
cigarette paper at an end of the tobacco rod that is intended to be
lit; and folding the overhanging foldable paper to substantially
cover the tobacco at the end of the tobacco rod. The foldable paper
may be adhered to the outside of the cigarette paper.
[0006] It has been found that closing the end of a smoking article
by folding over a separately applied outer layer of paper has
advantages over methods that rely on folding over an extension of
the cigarette paper itself. It is possible, for example, to obtain
an extending portion of the cigarette paper by tapping the smoking
article or standing it on its filter end on a vibrating table to
cause the tobacco to settle further down inside the cigarette
paper. However, the tobacco (smoking material) is of a non-uniform
nature and hence different components will settle to different
levels, and give an inconsistency to the smoking quality.
Alternatively, the tobacco can be pressed down inside the cigarette
paper, but this gives a non-uniform density that again results in
an inconsistent smoking quality. Wrapping a separate foldable paper
around the cigarette paper removes any need to redistribute or
otherwise manipulate the tobacco once the smoking article has been
assembled, so that quality can be maintained. Also, keeping the
tobacco rod in the structure in which it is initially fabricated
maintains the clean flat cut end of the tobacco, which offers a
much better surface against which the fold the foldable paper than
can be obtained through tapping, vibrating or compressing, which
tend to modify the tobacco surface and make it less flat and
robust. Hence the folding can be more easily and efficiently
performed, and the resulting folded end can have a neater
appearance.
[0007] Any paper that can be folded over to close the end of the
tobacco rod can be used, for example, standard cigarette paper as
used to wrap the tobacco and form the tobacco rod. However, a
porous paper is beneficial, as it makes it easier for the smoker to
draw on the cigarette when lighting it, since more air can flow
through the paper. Also, porous paper is typically thinner and
lighter than standard cigarette paper, so that it can be folded
more easily and neatly, giving a more compact folded end.
Therefore, in some embodiments, the foldable paper is a lighter
weight paper than the cigarette paper. For example, the foldable
paper may have a porosity greater than 3,000 CU, or greater than
6,000 CU, or greater than 12,000 CU, or greater than 24,000 CU. In
some embodiments, the foldable paper may be porous plug wrap paper.
This is particularly thin and light with ample porosity so as not
to impede drawing, and is further already readily available in the
tobacco industry.
[0008] The foldable paper may be embossed with one or more crease
lines along which the overhanging foldable paper is folded.
Providing such crease lines facilitates the paper folding, in that
folding becomes easier as less force is needed to bend the paper,
and the folds more readily form in the intended positions. This
gives a more consistent appearance to the folded end. The foldable
paper may be provided pre-embossed. Alternatively, the method may
further comprise, before adhering the foldable paper to the
cigarette paper, embossing the foldable paper with one or more
crease lines along which the overhanging foldable paper is to be
folded.
[0009] The foldable paper encircling the tobacco rod may extend
over only part of the length of the tobacco rod, or alternatively
the foldable paper encircling the tobacco rod may extend over
substantially the whole length of the tobacco rod. The former
arrangement allows a minimum amount of paper to be used, thus
saving materials and reducing costs. The latter arrangement, if
applied to a partially completed smoking article lacking a filter,
allows the edge of the foldable paper remote from the overhanging
part to be covered with tipping paper when the filter is attached
to the tobacco rod. This gives a neat appearance to the smoking
article and also removes an exposed edge that could otherwise
become caught or torn during later handling of the smoking
article.
[0010] In some embodiments, adhering the foldable paper to the
cigarette paper comprises: applying adhesive to the foldable paper;
bringing the smoking article into contact with the foldable paper
such that an edge of the foldable paper adheres to the cigarette
paper; and carrying the smoking article in a vacuum flute on the
outer surface of a rotating drum, the smoking article arranged with
its longitudinal axis parallel to the rotation axis of the drum, so
as to bring the smoking article into contact with a curved static
plate spaced apart from the drum by a distance less than the
diameter of the smoking article, contact with the plate causing the
smoking article to rotate about its own longitudinal axis so that
it rolls over the plate as the drum rotates, the rolling causing
the foldable paper to wrap around the smoking article. Since this
technique relies on individual pieces of foldable paper applied to
individual smoking articles, it is suitable for a foldable paper
that extends over any length of the tobacco rod. It is merely
necessary to use an appropriately sized foldable paper at the start
of the process. Rotating drums with vacuum flutes are widely used
in smoking article manufacture, so an existing production line may
be readily adapted to include apparatus for performing this method
of applying the foldable paper.
[0011] Further, for embodiments in which the foldable paper is
applied as a individual piece, the foldable paper may be shaped
along an edge such that the overhanging foldable paper has an edge
profile that gives a reduced amount of overlapped paper after
folding compared to a straight edge. This can be used to give a
neater appearance to the folded end, and may also give a fold
arrangement that maintains its folded position better with less
tendency for the folds to spring apart after folding.
[0012] In other embodiments, adhering the foldable paper to the
cigarette paper comprises: arranging the smoking article in a
sequence of smoking articles arranged end to end but spaced apart
by a distance equal to the desired length of the overhanging
foldable paper; feeding the sequence of smoking articles onto a
continuous length of foldable paper, the foldable paper having a
width at least equal to the circumference of the tobacco rods;
wrapping the foldable paper around the smoking articles to encircle
the tobacco rods, and adhering it in place; and cutting through the
foldable paper flush to an end of each smoking article, to separate
the smoking articles and form the overhanging foldable paper.
Alternatively, adhering the foldable paper to the cigarette paper
may comprise: arranging the smoking article in a sequence of
smoking articles arranged end to end in pairs where the articles in
each pair abut at their adjacent ends and the pairs are spaced
apart by a distance equal to twice the desired length of the
overhanging foldable paper; feeding the sequence of smoking
articles onto a continuous length of foldable paper, the foldable
paper having a width at least equal to the circumference of the
smoking articles; wrapping the foldable paper around the smoking
articles to encircle the tobacco rods, and adhering it in place,
and cutting through the foldable paper where the smoking articles
in each pair abut and also at the midpoint of the spaces between
the pairs, to separate the smoking articles and form the
overhanging foldable paper. These techniques give a foldable paper
that extends over the full length of the tobacco rod. The
techniques can be implemented by adapting apparatus currently used
for applying a second paper layer to double-wrapped tobacco
rods.
[0013] In various embodiments, folding the overhanging foldable
paper may comprise carrying the smoking article in a vacuum flute
on the outer surface of one or more rotating drums so as to bring
the overhanging foldable paper into contact with one or more
folding devices that bend the overhanging foldable paper inwards
over the tobacco at the end of the tobacco rod. As mentioned above,
rotating drums with vacuum flutes are already commonly used in
smoking article production, so their application to the methods of
the present invention allows the invention to be conveniently
implemented without extensive investment in new and complex
apparatus.
[0014] A variety of folding devices may be employed to achieve
different folding effects and number of folds. For example, the one
or more folding devices may comprise a reciprocating tucker with a
width less than the diameter of the smoking article that extends
partially over the end of the tobacco rod flush with the tobacco
therein to create a first fold and then retracts, a fixed tucker
with a width less than the diameter of the tobacco rod and a
surface that is flush with the tobacco against which the end of the
tobacco rod passes to create a second fold opposite the first fold,
and a pair of static plough folders providing surfaces flush with
the tobacco and having oppositely disposed converging edges,
against which the end of tobacco rod passes to form third and
fourth folds opposite one another and orthogonal to the first and
second folds. This gives a four-way envelope-style fold.
[0015] Alternatively, the one or more folding devices may comprise
a curved static plate spaced apart from the rotating drum by a
distance less than the diameter of the smoking article, contact
with the plate causing the smoking article to rotate about its own
longitudinal axis so that it rolls over the plate as the drum
rotates, and a plough folder fixed to the plate and comprising a
surface flush with the end of the tobacco rod that has an edge that
converges towards the drum in the direction of rotation of the drum
such that as the smoking article rolls over the plate the end of
the tobacco rod passes against the surface and the overhanging
foldable paper is engaged by the converging edge and is gradually
folded inwards over the tobacco in a continuous fold.
[0016] In a further alternative, the one or more folding devices
may comprise a curved static plate spaced apart from the rotating
drum by a distance less than the diameter of the smoking article,
contact with the plate causing the smoking article to rotate about
its own longitudinal axis so that it rolls over the plate as the
drum rotates, and a sequence of teeth extending from the plate
towards the drum and having surfaces flush with the end of the
tobacco rod, each tooth engaging a part of the overhanging foldable
paper and creating a fold as the smoking article rolls over the
plate, each fold overlapping the previous fold. This produces an
iris-style fold, where the number of individual overlapping folds
is determined by the number of teeth. Hence, the number of teeth
can be selected to achieve a particular appearance of the iris
fold.
[0017] In another alternative, the one or more folding devices may
comprise a curved static plate spaced apart from the rotating drum
by a distance less than the diameter of the smoking article,
contact with the plate causing the smoking article to rotate about
its own longitudinal axis so that it rolls over the plate as the
drum rotates, and a rotatable cam associated with each vacuum flute
on the rotating drum, each cam having a surface flush with the end
of the tobacco rod and configured to sweep across the end of the
tobacco rod as the smoking article rolls over the plate, the edge
of the cam pushing against the overhanging foldable paper to fold
it inwards over the tobacco. In this context, the cam may have a
smooth edge that creates a continuous fold, or alternatively the
cam may have a toothed edge that creates a series of overlapping
folds. This latter option gives an iris fold in which the number of
folds corresponds to the number of teeth.
[0018] In a yet further alternative, the one or more folding
devices may comprise a pair of adjacent rotatable surfaces flush
with the end of the tobacco rod that sweep outwardly over the end
of the tobacco rod from the rear of the smoking article as it is
carried by the rotating drum to create first and second adjacent
folds, and a static tucker having a surface flush with the end of
the tobacco rod against which the end of the tobacco rod passes to
create a third fold. This gives a three-way fold.
[0019] In another embodiment, the one or more folding devices may
comprise a curved static plate spaced apart from the rotating drum
by a distance less than the diameter of the smoking article,
contact with the plate causing the smoking article to rotate about
its own longitudinal axis so that it rolls over the plate as the
drum rotates, and a rotating threaded screw positioned with its
axis of rotation orthogonal to the axis of rotation of the rotating
drum and substantially tangential to the perimeter of the drum, and
the threaded surface flush with the end of the tobacco rod such
that the screw thread engages with the overhanging foldable paper
as the smoking article rolls across the plate and the rotation of
the screw folds the paper inwards over the tobacco. A number of
individual overlapping folds are produced, giving an iris-style
fold. The pitch of the screw thread determines the number of
folds.
[0020] In a further embodiment, the one or more folding devices may
comprise a protrusion in a vacuum flute of a first rotating drum
that pushes part of the overhanging foldable paper inwards over the
tobacco when the smoking article enters the vacuum flute to create
a first fold, a further protrusion in a vacuum flute of a second,
adjacent, rotating drum to which the smoking article is transferred
from the first drum, the further protrusion pushing part of the
overhanging foldable paper inwards over the tobacco when the
smoking article enters the flute to create a second fold opposite
the first fold, and a pair of static, plough folders providing
oppositely disposed surfaces flush with the end of the tobacco rod
and having converging edges, against which the end of tobacco rod
passes to create third and fourth folds opposite one another and
orthogonal to the first and second folds. This produces a four-way
envelope fold.
[0021] In an alternative embodiment, the one or more folding
devices may comprise a protrusion in a vacuum flute of a first
rotating drum that pushes part of the overhanging foldable paper
inwards over the tobacco when the smoking article enters the vacuum
flute to create a first fold, a further protrusion in a vacuum
flute of a second, adjacent, rotating drum to which the smoking
article is transferred from the first drum, the further protrusion
pushing part of the overhanging foldable paper inwards over the
tobacco when the smoking article enters the flute to create a
second fold opposite the first fold, and a pair of reciprocating
folders that sweep inwardly over the end of the tobacco rod and
then retract to create third and fourth folds opposite one another
and orthogonal to the first and second folds. Again, a four-way
envelope fold is produced.
[0022] Alternatively, the one or more folding devices may comprise
a protrusion in a vacuum flute of a first rotating drum that pushes
part of the overhanging foldable paper inwards over the tobacco
when the smoking article enters the vacuum flute to create a first
fold, a further protrusion in a vacuum flute of a second, adjacent,
rotating drum to which the smoking article is transferred from the
first drum, the further protrusion pushing part of the overhanging
foldable paper inwards over the tobacco when the smoking article
enters the flute to create a second fold opposite the first fold, a
fixed folder disposed at the side of a vacuum flute of a third,
adjacent, rotating drum to which the smoking article is transferred
from the second drum which engages with the overhanging foldable
paper as the smoking article enters the vacuum flute and pushes the
paper inwards over the tobacco to create a third fold orthogonal to
the first and second folds, and a further fixed folder disposed at
the side of a vacuum flute of a fourth, adjacent, rotating drum to
which the smoking article is transferred from the third drum which
engages with the overhanging foldable paper as the smoking article
enters the vacuum flute and pushes the paper inwards over the
tobacco to create a fourth fold opposite to the third fold. This is
further alternative way to produce a four-way envelope fold.
[0023] In any of the above methods including protrusions in vacuum
flutes, one or both of the said protrusion and the further
protrusion may be configured to move between an extended position
for effecting the first or second fold as the smoking article
enters the vacuum flute, and a retracted position after the fold is
effected in which the protrusion does not protrude into the flute.
Retracting the protrusion after folding allows further motion of
the smoking article to proceed with less impediment, giving a
smoother production process. Also, the gradual folding motion of a
moving protrusion can produce a better quality fold than the more
abrupt impact between a smoking article and a fixed protrusion.
[0024] In another embodiment, the one or more folding devices may
comprise a first pair of pincers longitudinally aligned with a
vacuum flute of a first rotating drum, and biased in an open
position to receive the overhanging foldable paper of a smoking
article in the vacuum flute, the pincers operable to close on the
received overhanging foldable paper and push opposite parts of the
paper inwards over the tobacco to create opposite first and second
folds, and a second pair of pincers longitudinally aligned with a
vacuum flute of a second rotating drum, and biased in a open
position to receive the overhanging foldable paper of the smoking
article when transferred to the vacuum flute after folding in the
vacuum flute of the first rotating drum, the pincers operable to
close on the remaining overhanging foldable paper and push the
opposite parts of the paper inwards over the tobacco to create
opposite third and fourth folds orthogonal to the first and second
folds.
[0025] Alternatively, the one or more folding devices may comprise
a first pair of pincers longitudinally aligned with a vacuum flute
of a first rotating drum, and biased in an open position to receive
the overhanging foldable paper of a smoking article in the vacuum
flute, the pincers operable to close on the received overhanging
foldable paper and push opposite parts of the paper inwards over
the tobacco to create opposite first and second folds, and one or
more supplementary folding devices associated with a second
rotating drum arranged to receive the smoking article after folding
with the first drum, and operable to fold the remaining opposite
parts of the paper inwards over the tobacco to create opposite
third and fourth folds orthogonal to the first and second
folds.
[0026] According to further embodiments, adhering the foldable
paper to the cigarette paper may comprise: applying adhesive to the
foldable paper; bringing the smoking article into contact with the
foldable paper such that an edge of the foldable paper adheres to
the cigarette paper; and introducing the smoking article onto a
lower surface that is spaced apart from an upper surface by a
distance less than the diameter of the smoking article, the upper
surface moving relative to the lower surface along a direction
parallel to the surfaces and orthogonal to the longitudinal axis of
the smoking articles such that contact with the surfaces causes the
smoking article to rotate about its longitudinal axis so that it
rolls over the lower surface as the upper surface moves, the
rolling causing the foldable paper to wrap around the smoking
article. The upper surface may comprise an endless belt rotating
around a pair of rollers.
[0027] Further, folding the overhanging paper may then comprise
using the rolling of the smoking article over the lower surface to
bring the overhanging foldable paper into contact with one or more
folding devices that bend the overhanging foldable paper inwards
over the tobacco at the end of the tobacco rod. The one or more
folding devices may comprise a series of teeth extending from the
lower surface towards the upper surface and having surfaces flush
with the end of the tobacco rod, each tooth engaging a part of the
overhanging foldable paper and creating a fold as the smoking
article rolls over the lower surface, each fold overlapping the
previous fold. Other folding devices may alternatively be used,
however.
[0028] Folding the overhanging foldable paper may comprise pushing
part of the paper inwards to create a first fold, pushing a further
part of the paper inwards to create a second fold opposite the
first fold, and trimming off some or all of the remaining, unfolded
paper. This reduces the amount of overlapping paper in the folded
end, making the smoking article easier to light.
[0029] The method may further comprise, after folding the
overhanging foldable paper, pushing against the end of the tobacco
rod with a pin having a width less than the diameter of the smoking
article to depress the folded paper and cause it to better maintain
its folded position. This is a simple way to overcome any tendency
of the folded paper to spring outwards slightly from its folded
position, and is preferable to the use of adhesive to hold the
folded end in place.
[0030] In some embodiments, the foldable paper is provided with
adhesive on all or part of the inner surface of the overhanging
portion, and the method further comprises, after folding the
overhanging paper, pressing against the end of the tobacco rod to
cause the folded paper to become adhered in its folded position.
The adhesive may be heat-activated, and pressing against the end of
the tobacco rod may include applying heat to the end of the tobacco
rod.
[0031] Also, the method may further comprise, in the event that the
smoking article is a partially fabricated smoking article,
attaching a filter unit to the end of the tobacco rod opposite to
the end intended to be lit. To speed production, the filter unit
may be attached to the end of the tobacco rod simultaneously with
the adhering and/or folding of the foldable paper.
[0032] In a further embodiment, the method may further comprise,
after folding the overhanging paper, inspecting the folded
overhanging paper for defects, and rejecting a smoking article
found to have a defective folded overhanging paper. The inspecting
may comprise capturing one or more images of the folded overhanging
paper and comparing the one or more images with one or more stored
images of non-defective folded overhanging paper. The captured
images comprise, for example, an end view of the folded overhanging
paper and/or a side view of the folded overhanging paper.
[0033] A second aspect of the present invention is directed to
apparatus configured to perform a method of making a smoking
article according to any embodiment of the first aspect.
[0034] A third aspect of the present invention is directed to a
smoking article comprising: a tobacco rod of tobacco wrapped in
cigarette paper; and a foldable paper adhered to the cigarette
paper such that the foldable paper encircles the tobacco rod and
overhangs the cigarette paper at an end of the tobacco rod that is
intended to be lit, the overhanging foldable paper folded to
substantially cover the tobacco at the end of the tobacco rod. The
foldable paper may be adhered to the outside of the cigarette
paper.
[0035] The foldable paper may be a porous paper, such as porous
plug wrap paper. The foldable paper may have a porosity greater
than 3,000 CU, or greater than 6,000 CU, or greater than 12,000 CU,
or greater than 24,000 CU. Further, the foldable paper may be
embossed with one or more crease lines along which the overhanging
foldable paper is folded. The foldable paper encircling the tobacco
rod may extend over only part of the length of the tobacco rod, or
over substantially the whole length of the tobacco rod.
[0036] The foldable paper may be shaped along an edge such that the
overhanging foldable paper has an edge profile that gives a reduced
amount of overlapped paper after folding compared to a straight
edge.
[0037] The overhanging foldable paper may be folded with a first
fold, a second fold opposite the first fold, a third fold
orthogonal to the first and second folds, and a fourth fold
opposite the third fold. In an alternative, the overhanging
foldable paper may be folded with a plurality of folds, each fold
overlapping the adjacent fold.
[0038] The smoking article may further comprise a filter unit
attached to the end of the tobacco rod opposite to the end intended
to be lit.
[0039] A fourth aspect of the present invention is directed to
apparatus for making a smoking article comprising: a first
sub-apparatus operable to receive a fully or partially fabricated
smoking article comprising at least a rod of tobacco wrapped in
cigarette paper and to adhere a foldable paper to the cigarette
paper such that the foldable paper encircles the tobacco rod and
overhangs the cigarette paper at an end of the tobacco rod that is
intended to be lit; and a second sub-apparatus operable to receive
a smoking article with an overhanging foldable paper produced by
the first sub-apparatus and to fold the overhanging foldable paper
to substantially cover the tobacco at the end of the tobacco
rod.
[0040] The first sub-apparatus and the second sub-apparatus may be
configured according to a range of different embodiments.
Additionally, the apparatus may further comprise a third
sub-apparatus operable to receive a smoking article with a folded
overhanging foldable paper from the second sub-apparatus and to
push a pin having a width less than the diameter of the smoking
article against the folded overhanging foldable paper to depress
the folded paper and cause it to better maintain its folded
position, and/or to apply pressure and/or heat to the folded
overhanging foldable paper to active adhesive on the overhanging
foldable paper and cause it to become adhered in its folded
position. Further, the apparatus may also comprise a fourth
sub-apparatus operable to attach a filter unit to the end of a
tobacco rod of a partially fabricated smoking article, opposite to
the end intended to be lit. Also, an inspection system may be
included, operable to inspect the folded overhanging paper for
defects and reject a smoking article found to have a defective
folded overhanging paper.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] For a better understanding of the invention and to show how
the same may be carried into effect reference is now made by way of
example to the accompanying drawings in which:
[0042] FIGS. 1A and 1B show cross-sectional side views of the end
of a smoking article provided with a foldable paper for closing the
lighting end of the smoking article, with the foldable paper
respectively in unfolded and folded positions, in accordance with
an embodiment of the invention;
[0043] FIG. 2 shows a schematic representation of a first
embodiment of a process for applying a foldable paper to a smoking
article;
[0044] FIGS. 3A and 3B show schematic, representations of examples
of a second embodiment of a process for applying a foldable paper
to a smoking article;
[0045] FIG. 4 shows a schematic representation of a first
embodiment of apparatus for folding overhanging foldable paper
applied to a smoking article;
[0046] FIGS. 5A-5D show a sequence of end views of a smoking
article having an applied overhanging foldable paper which is
successively folded using four folds;
[0047] FIG. 6 shows a schematic side representation of a second
embodiment of apparatus for folding overhanging foldable paper
applied to a smoking article;
[0048] FIG. 7 shows a schematic side representation of a third
embodiment of apparatus for folding overhanging foldable paper
applied to a smoking article;
[0049] FIG. 8 shows an end view of a smoking article having an
applied foldable paper folded into an iris-style fold such as by
the apparatus of FIG. 7;
[0050] FIG. 9 shows a schematic side representation of a fourth
embodiment of apparatus for folding overhanging foldable paper
applied to a smoking article;
[0051] FIG. 10 shows a schematic side representation of a fifth
embodiment of apparatus for folding overhanging foldable paper
applied to a smoking article;
[0052] FIG. 11 shows a schematic side representation of a sixth
embodiment of apparatus for folding overhanging foldable paper
applied to a smoking article;
[0053] FIG. 11A shows an end view of a smoking article having an
applied foldable paper folded into a three-way fold, such as by use
of the apparatus of FIG. 11;
[0054] FIG. 12 shows a perspective schematic representation of a
first embodiment of apparatus for applying a foldable paper to a
smoking article and folding the paper;
[0055] FIGS. 13A and 13B shows cross-sectional side views of a
smoking article having first and second folds made to its
overhanging foldable paper using the apparatus of FIG. 12;
[0056] FIG. 14 shows a perspective schematic representation of a
second embodiment of apparatus for applying a foldable paper to a
smoking article and folding the paper;
[0057] FIG. 15 shows a perspective schematic representation of a
third embodiment of apparatus for applying a foldable paper to a
smoking article and folding the paper;
[0058] FIGS. 16A, 16B, 16C and 16D show assorted side and
perspective views of a further embodiment of apparatus for folding
overhanging foldable paper applied to a smoking article;
[0059] FIG. 17 shows a schematic side representation of an
alternative embodiment of apparatus for applying a foldable paper
to a smoking article and folding the paper;
[0060] FIGS. 18A, 18B and 18C show end views of smoking articles
having applied foldable papers folded according to three further
embodiments;
[0061] FIGS. 19A and 19B show schematic side representations of two
embodiments of apparatus for pressing a pin into previously folded
paper of a smoking article to improve the closure;
[0062] FIG. 20 shows a schematic side representation of a smoking
article having a pressing pin applied to its folded paper, such as
with the apparatus of FIG. 19A or 19B;
[0063] FIG. 21 shows three examples of shaped-edge foldable paper
that may be utilised in embodiments of the present invention;
[0064] FIG. 22 shows a plan view of a foldable paper with adhesive
applied according to an embodiment of the invention; and
[0065] FIG. 23 shows a view from above of an example inspection
system for detecting smoking articles with defective folded ends,
according to another embodiment.
DETAILED DESCRIPTION
[0066] The present invention proposes closing the end of a smoking
article by providing an extra portion of paper at the end of the
tobacco rod of the smoking article that is intended to be lit, so
that the paper overhangs the end of the rod, and then folding the
overhanging paper inwards to cover over the exposed tobacco. A
tobacco rod comprises a cylinder of tobacco wrapped in cigarette
paper, with the end of the tobacco substantially flush with the end
of the paper. According to the invention, an additional piece of
foldable paper is stuck with adhesive around the outside of the
cigarette paper after the tobacco rod is formed, so that the
foldable paper encircles the tobacco rod, and extends beyond the
end of the tobacco rod by an amount that is sufficient to
substantially enclose the tobacco when the overhanging paper is
folded inwards.
[0067] FIG. 1A shows a longitudinal cross-sectional view through
the end of a tobacco rod having an overhang of foldable paper
according to an embodiment of the invention. The tobacco rod 10
comprises tobacco 12 wrapped in a cigarette paper 14 in the
conventional manner, with the addition of a portion of foldable
paper 16 that is adhered around the circumference of the end
portion of the cigarette paper 14. A length 18 of the foldable
paper 16 extends beyond the end of the tobacco 12 and the cigarette
paper 14 to form an overhang.
[0068] FIG. 1B shows the same view of the tobacco rod 10 after
folding of the foldable paper 14. The overhanging part 18 of the
foldable paper 14 is folded inwards against the end surface of the
tobacco 12 so as to close the end of the tobacco rod and cover the
tobacco that would otherwise be exposed at the end of the tobacco
rod that is intended to be lit.
[0069] The term "tobacco" as used herein is intended to be
understood as including tobacco material (such as stem, lamina,
tobacco dust, cut tobacco and expanded tobacco), reconstituted
tobacco and substitute tobacco materials.
[0070] The foldable paper may be any paper that can conveniently be
folded in the required manner. A piece of regular cigarette paper,
the same as the cigarette paper of the tobacco rod, may be used.
However, it has been found that a more satisfactory result can be
achieved if a paper of a lighter weight than cigarette paper is
used. A lighter paper is thinner and hence more easily folded.
Also, a lighter paper has greater porosity, which makes it easier
for the smoker to draw on the smoking article when lighting it, so
that ease of lighting is less impaired by the presence of the
folded paper. For example, porous plug wrap paper, of the type
generally used to wrap around the acetate tow core of a cigarette
filter unit, may be used. This is a thin paper with a high
porosity, and is also conveniently readily available in the
industry due it being already used in cigarette manufacture. More
generally, paper with a porosity greater than 3,000 CORESTA units
(CU), or greater than 6,000 CU, or greater than 12,000 CU, or
greater than 24,000 CU is recommended, although papers with other
porosity values are not excluded.
[0071] FIGS. 1A and 1B show an embodiment in which the foldable
paper is relatively short compared to the overall length of the
tobacco rod, so that the foldable paper extends only a short
distance along the length of the cigarette paper. For example, the
length of foldable paper that overlaps the cigarette paper may be
substantially equal to the length that overhangs the end of the
tobacco rod. The length may be selected according to how much paper
it is desired to use (a short length obviously using less paper and
hence being less costly), and how large an area of overlap is
needed to provide a secure adherence of the foldable paper to the
cigarette paper. While a short length is economic, long lengths may
be used instead, up to and including a length of foldable paper
that extends over substantially the entire length of the tobacco
rod. This latter example has the advantage that the end of the
foldable paper opposite to the folded end can be hidden under a
tipping paper used to join a filter unit to the tobacco rod, giving
a smooth outer surface to the tobacco rod of the completed smoking
article. This gives an improved aesthetic appearance to the smoking
article, and also protects the edge of the foldable paper and
prevents it becoming caught and possible torn during subsequent
processing and handling of the smoking article.
[0072] For foldable paper applied over the length of the tobacco
rod, it is convenient to apply the foldable paper to the tobacco
rod before the tobacco rod is assembled with a filter unit to form
a completed smoking article, so that the edge of the foldable paper
can be wrapped under the tipping paper as mentioned above. However,
for embodiments using a shorter length of foldable paper, the
foldable paper can be applied to the tobacco rod at any stage in
the fabrication of the smoking article, including before or after a
filter unit is joined to the tobacco rod. Hence, methods of the
invention are applicable to both fully and partially fabricated
smoking articles, where it is merely required that a tobacco rod be
provided for adherence of the foldable paper to the cigarette paper
thereof. If the smoking article is only partly fabricated, and
comprises a tobacco rod without a filter at the time of applying
the foldable paper, a filter unit can be added subsequently to form
a filter smoking article. Alternatively, the smoking article may be
intended as a plain cigarette, so that no filter is added to the
tobacco rod. Consequently, in the following description and
appended claims, the term "smoking article" is intended to cover
both substantially completed smoking articles, and partially
completed smoking articles (which may comprise a tobacco rod only).
Furthermore, if the smoking article is only partly fabricated, a
filter unit can be added simultaneously with the application and
folding of the foldable paper. This combines two handling stages
into one and hence reduces production time for the smoking
articles. Simultaneous processing in this way is facilitated by the
fact that the application and folding of the foldable paper can be
carried out using conventional smoking article manufacturing
apparatus such as is employed for filter attachment with only small
modifications, so that the additional processes can be readily
integrated into existing production lines.
[0073] According to one embodiment, it is proposed that the
foldable paper be supplied as individual glued pieces that are
applied to individual smoking articles, and then wrapped around the
tobacco rods so that the glue adheres to the cigarette paper and
holds the foldable paper in place.
[0074] A convenient way to handle the smoking articles during this
process is to carry them on the surface of one or more rotating
drums, as is commonly done in existing smoking article
manufacturing processes. A rotatable drum, mounted on a spindle and
driven by a motor at an appropriate speed of rotation to
synchronise with related machinery, has a plurality of longitudinal
grooves or flutes in its outer surface around its circumference,
each flute arranged parallel to the rotational axis of the drum and
dimensioned to accommodate a smoking article. Each flute has one or
more holes in its surface that are connected to a vacuum pump so
that a smoking article can be held in the flute by suction. The
smoking articles can thereby be received onto a drum or discharged
from a drum, including being passed from one drum to an adjacent
drum, by turning the vacuum on and off at the appropriate times.
One or more drums can be used to carry smoking articles past a
variety of processing devices that perform different manufacturing
steps on the smoking articles.
[0075] FIG. 2 shows a schematic representation of the use of
rotating drums for applying a foldable paper to a smoking article,
shown as a view along the axes of rotation of the drums. In this
example, the foldable paper is provided as a pre-wound roll 20 of
appropriate paper 22, such as porous plug wrap, the paper on the
roll 20 having a width that is the required length of the foldable
paper when it is wrapped around a tobacco rod (i.e. the length of
the overhang plus the length of the portion that extends over the
cigarette paper along all or part of the tobacco rod). The paper 22
is unwound from the roll 20 and passed through a pair of embossing
rollers 23, which emboss the paper with one or more crease lines
corresponding to the lines along which the paper is to be folded to
close the end of the smoking article. The crease lines facilitate
the later folding of the foldable paper, but need not be included,
so the embossing rollers 23 may be absent from the apparatus.
Alternatively, the foldable paper 22 may be provided pre-embossed
on the roll 20. The foldable paper then travels past a glue
applying device 26 which applies adhesive 24 to one side of the
paper 22. Any suitable glue applying device maybe used, such as a
roller system or a glue spray unit. After gluing, the paper 22 from
the roll 20 is then cut to the correct length using a cutting
device 28. The correct length is a length sufficient to completely
encircle the smoking article, with optionally an overlapping edge.
In this example, the cutting device 28 is a vacuum cutting drum 28.
This is a drum with a plurality of cutting blades 29 spaced around
its circumference. Rotation of the drum 28 brings the blades in
turn into contact with the paper 22, and each blade cuts off a
correct length 30 of the paper 22. The surface of the drum 28 is
also provided with suction holes through which a vacuum is applied
to hold the individual foldable papers 30 against the drum 28 as it
rotates.
[0076] The foldable paper 30, now glued and of the necessary size,
is carried by the rotation of the vacuum cutting drum 28 into a
position in which its leading edge extends into the path of a
smoking article 32 being carried on the surface of a first rotating
drum 34. The smoking article 32 is delivered to the drum 34 from a
hopper or an adjacent drum, and taken up by a flute on the surface
of the drum 34. As the drum 34 rotates, the smoking article 32
comes into contact with the leading edge of the foldable paper 30,
and the foldable paper 30 sticks to the cigarette paper of the
smoking article 32 because of the previously applied adhesive. This
sticking action pulls the foldable paper 30 off the vacuum cutting
drum 28, so that the foldable paper is now carried by the smoking
article 32. The vacuum cutting drum 28 and the rotating drum 34 are
positioned relative to one another along the longitudinal direction
of the smoking article 32 so as to give the required length of
overhang when the paper 30 is stuck to the smoking article 32.
[0077] The first rotating drum 34 rotates further, carrying the
smoking article 32 and attached foldable paper 30 with it. A second
rotating drum 36 is positioned adjacent to the first drum 34 and
rotating in an opposite direction about a parallel axis. The
rotation of the drums 34, 36 brings the smoking article 32 into a
flute on the second drum 36, and appropriate switching of the
vacuum-suction in the two flutes transfers to the smoking article
to the second drum 36.
[0078] A rolling plate 38 is positioned adjacent to the second drum
36. The rolling plate 38 is a static plate having a curved surface
40 with a profile that matches the outer circumference of the drum
36. The plate 38 is located such that the curved surface 40 is
spaced from the surface of the drum 36 by slightly less than the
amount by which the smoking article 32 protrudes from the surface
of the drum 36. As the drum 36 rotates it brings the smoking
article 32 into the space between the drum 36 and the surface 40 of
the rolling plate 38, but in an interference fit owing to the
spacing. This interference fit causes the smoking article 32 to
rotate about its own longitudinal axis within the flute (in an
opposite direction to that of the rotation of the drum) as the
smoking article is carried through the space by the drum 36, so
that the smoking article 32 in effect rolls over the curved surface
40 of the rolling plate 38. This rolling also causes the smoking
article 32 to roll over its attached foldable paper 30, so that the
foldable paper 30 adheres right around the circumference of the
tobacco rod and forms a tube that extends beyond the end of the
tobacco rod. When the smoking article 32 is carried past the
rolling plate 38, it is ready for folding of the overhanging
foldable paper.
[0079] Application of the foldable paper according to the
embodiment of FIG. 2 can be used for any length of foldable paper,
and for partially and fully assembled smoking articles.
[0080] A potential problem that may arise from use of a rolling
plate to apply the foldable paper is that of ends fall-out, in
which tobacco pieces at the open end of a tobacco rod can become
loosened and may subsequently be lost. In the present case, this
can be caused by the pressure exerted on the end of the smoking
article by the rolling plate. This can be addressed by appropriate
configuration of the rolling plate and rotating drum combination to
reduce the pressure applied to the smoking article, and/or to shift
the position(s) along the length of the smoking article at which
pressure is applied.
[0081] An alternative approach is pre-gluing of the cigarette paper
before fabrication of the smoking article. One or more lines or
dots of adhesive can be applied to the inside surface of the
cigarette paper before it is wrapped around the tobacco, the lines
or dots positioned to coincide with the end of each smoking
article. The end part of the tobacco is thereby secured within the
cigarette paper, and is less likely to be loosened during
application of the foldable paper.
[0082] FIG. 3A shows a schematic representation of a technique for
applying a foldable paper that extends over the full length of the
tobacco rod of the smoking article. In this case, a continuous
length of foldable paper 42 is fed from a roll (not shown), and
arranged in the horizontal direction. The paper has a width which
is at least the circumference of the smoking article so that it can
completely encircle the tobacco rod when wrapped around the smoking
article. Possibly the width of the foldable paper is greater than
the circumference of the smoking article, so that there is an
overlap when the foldable paper is wrapped around the tobacco rod,
which may assist with gluing, for example. Adhesive is applied to
the upper surface of the foldable paper, at least along one edge.
The amount and position of the adhesive can be selected as desired,
depending on how much of the surface of the foldable paper it is
desired to stick to the cigarette paper, and whether an overlap is
used.
[0083] A continuous stream of smoking articles 44 is delivered onto
the upper surface of the foldable paper 42, as indicated in section
A of the Figure. The smoking articles do not have filters, and may
comprise only a tobacco rod in the form of tobacco 46 wrapped in
cigarette paper 48. The smoking articles 44 are arranged end to end
in a line, and positioned along the length of the foldable paper
42. However, the smoking articles are spaced apart along the line
by a distance d that is equal to the desired length of the overhang
of the foldable paper.
[0084] The smoking articles 44 and the foldable paper 42 are moved
along together, as shown by the arrow in the Figure, and fed into a
tube (not shown) having an inner diameter substantially the same as
the diameter of the smoking articles 44. As shown in section B of
the Figure, the wall of the tube guides the foldable paper 42
around the smoking articles 44, and the adhesive causes the
foldable paper 42 to stick in place so as to encircle the cigarette
papers 48 of the smoking article 44. This results in a continuous
tube of foldable paper 42 with smoking articles 44 spaced apart in
a line inside the tube.
[0085] Finally, the continuous tube is cut into sections, as shown
in section C of the Figure. A cutting device 50, such as a blade,
is arranged to cut through the tube of foldable paper 42 at
intervals corresponding to the length of the smoking articles 44
plus the foldable paper overhang. The cuts are positioned to be
flush with one end of each tobacco rod. This divides the continuous
tube into individual smoking articles 44 each comprising a tobacco
rod with a foldable paper wrapped around it that extends over the
whole length of the tobacco rod and further extends beyond one end
of the tobacco rod to give the desired overhang 18 for folding.
[0086] Alternatively, the stream of smoking articles 44 may be
delivered onto the foldable paper 42 in pairs, with the two article
in each pair being substantially touching or abutting at their
adjacent ends, and the pairs being spaced apart by a distance 2d,
which is equal to twice the desired length of the overhang of
foldable paper. Once wrapped in the continuous tube of foldable
paper 42, the smoking articles 44 are then separated by the tube
being cut at the midpoint of each space between pairs of smoking
articles, and also at the point where the articles 44 in each pair
abut.
[0087] FIG. 3B shows a schematic representation of this
arrangement, using the same reference numerals as FIG. 3A. A second
cutting blade 50' is shown in phantom to indicate, in conjunction
with the first cutting blade 50, the two cutting points relative to
each pair of smoking articles 44. In reality, the cuts can all be
effected by a single cutting device if preferred.
[0088] An advantage of these methods of applying the foldable paper
to the smoking articles is that they can be readily adapted from
known apparatus for making cigarettes With a double-wrapped tobacco
rod. Such cigarettes have an outer layer of paper overlying the
cigarette paper, and the tobacco rods for these cigarettes can be
made by delivering a continuous stream of single-wrapped tobacco
rods, arranged end to end with no spaces, onto a glued length of
outer wrap which is then wrapped around, the tobacco rods. The
resulting continuous tube is then cut at each break between the
single-wrapped rods. By adjusting the supply of tobacco rods so as
to give the necessary spacing between the rods, and using a cutting
device that can cut through the foldable paper tube without
crushing or deforming the overhang, the embodiments of the present
invention as shown in FIGS. 3A and 3B may be implemented.
[0089] The present invention further proposes a number of
techniques for folding the overhanging foldable paper so as to
cover the exposed end of the tobacco rod. It is proposed that these
techniques be implemented by carrying the smoking articles, already
provided with overhangs of foldable paper, on one or more rotating
drums like those described above with regard to FIG. 2 that bring
the foldable paper overhangs into contact with one or more folding
devices that engage the paper to push it inwards over the tobacco.
Different devices can be employed to achieve different folding
effects, with various numbers and arrangements of folds.
[0090] FIG. 4 shows a schematic view of a first example of a
folding arrangement, comprising four folding devices arranged next
to a rotating drum. The drum 52 carries smoking articles 54 in
vacuum flutes on its outer surface, as described before, the
smoking articles having been delivered thereto from a hopper or
another rotating drum. As the drum rotates, it carries the smoking
articles past the four folding devices in turn. Each folding device
comprises a substantially flat surface arranged orthogonal to the
axis of rotation of the drum 52 and hence also to the longitudinal
axes of the smoking articles 54. Further, the surfaces of the
folding devices are located in a plane that is substantially flush
with the end surfaces of the tobacco in the tobacco rods of the
smoking articles 54 as they are carried by the drum 52.
[0091] The first folding device 56 comprises a reciprocating tucker
in the form of surface having a width that is less than the
diameter of the smoking articles. It has a fixed location with
respect to the drum 52, but which can move back and forth along a
direction perpendicular to its width which is also substantially
parallel to a tangent of the drum 52, as shown by the arrow in the
Figure. In a starting position, the reciprocating tucker occupies a
position retracted from the drum which allows a smoking article to
pass by untouched. When a smoking article 54 reaches the position
54a, past the reciprocating tucker 56, the tucker moves forward so
that its surface slides partially over the end of the tobacco rod
on the trailing side, pushing part of the overhanging foldable
paper before it to that the paper is pushed inwards and over the
tobacco. The tucker 56 is then retracted before it reaches the
foldable paper overhanging the opposite side of the smoking article
54. A first fold is thereby formed.
[0092] The second folding device 58 comprises a static tucker,
again in the form of a surface having a width less than the
diameter of the smoking article. It occupies a fixed position with
respect to the drum 52, arranged with its width substantially
perpendicular to a further tangent of the drum 52. It is located
such that the smoking article, carried by the rotating drum and
already having a first fold, passes behind the tucker 58 (with
respect to the viewing direction of FIG. 4) with the surface of the
tobacco flush with the surface of the tucker 58. The front edge of
the tucker pushes against the overhanging foldable paper as the
smoking article moves into the tucker, and folds it over against
the tobacco, to create a second fold opposite the first fold. The
presence of the first fold on the trailing side of the smoking
article means that the smoking article is free to pass under the
static tucker once the leading side of the paper has been folded as
the second fold. The positions of the first folding device 56 and
the second folding device 58, and the movement of the first folding
device relative to the speed of the drum 52, are arranged so that
the first tucker 56 makes its fold just prior to the smoking
article starting to be folded by the second tucker 58. Upon
completion of the second fold, the first tucker 56 retracts to
allow the next smoking article to pass by prior to the first tucker
moving forward again to create a first fold on the trailing
side.
[0093] The third folding device 60 comprises a static plough
folder. This has a surface with a tapering profile, arranged to
offer an edge to the incoming leading side of the smoking article
that begins at one side of the smoking article end (with respect to
the direction of travel of the smoking article) and converges
towards the midline of the smoking article end as the travel path
of the smoking article proceeds. Thus, as the smoking article is
carried past the folder, the edge engages the overhanging paper at
the side of the smoking article, and gradually pushes it inwards
and over against the end of the tobacco rod as this end passes
against the surface of the folder. This creates a third fold that
is substantially at right angles to the first and second folds.
[0094] Finally, the fourth folding device 62 comprise a further
static plough folder. This has the same structure as but the
opposite configuration to the third folding device 60, so that the
converging edge is positioned on the other side of the smoking
article. Therefore, travel of the smoking article past this plough
folder engages the opposite overhanging paper, and folds it inwards
against the end of the tobacco rod to create a fourth fold opposite
to the third fold. For reasons of space, the fourth folding device
62 will probably need to be positioned downstream from the third
folding device 60, so that each of the surfaces can extend
sufficiently far across the end of the tobacco rod to completely
fold over the overhanging foldable paper.
[0095] The folding devices of FIG. 4 create an envelope fold
comprising two opposite folds overlaid by two further opposite
folds that are orthogonal to the first opposite folds.
[0096] FIGS. 5A-5D show schematic representations of the end view
of a smoking article being provided with an envelope fold, such as
by use of the apparatus of FIG. 4. A first fold 64 is followed by a
second fold 66 on the opposite side of the smoking article, a third
fold 68 at right angles to the first and second folds, and a fourth
fold 70 opposite to the third fold. The exposed tobacco 72 at the
end of the tobacco rod is gradually covered over.
[0097] FIG. 6 shows a schematic representation of a further example
of folding apparatus. A rotating drum 74 that carries smoking
articles 54 in vacuum flutes on its surface, as before, is used in
conjunction with a static rolling plate 76, like the rolling plate
38 described with reference to FIG. 2. As before, the interference
fit of the smoking article 54 between the surface of the rotating
drum 74 and the curved surface of the rolling plate 76 causes the
smoking article 54 to rotate about its own longitudinal axis so
that it rolls over the surface of the plate 76. In this example,
the rolling plate 76 is provided with a plough folder 78. The
plough folder 78 is fixed to the rolling plate 76 and comprises a
surface extending from the curved surface of the rolling plate 76
that is in the plane of the ends of the tobacco rods of the smoking
articles 54 so that the ends of the rods pass against the surface
as the smoking articles 54 roll over the rolling plate 76. The
surface of the plough folder 78 has an edge that begins at the
surface of the rolling plate, and converges towards the surface of
the drum, so that the far end of the plough folder extends at least
halfway across the space between the rolling plate 76 and the drum
74. When a smoking article is carried onto the rolling plate 76 by
rotation of the drum 74, the front end of the plough folder 78
engages with the overhanging foldable paper at the end of the
tobacco rod, and gradually pushes it over and inwards against the
end surface of the tobacco. As the smoking article 54 rolls over
the rolling plate 79, the edge of the plough folder 78 continually
engages with a new part of the overhanging foldable paper and folds
it over against the tobacco. As the smoking article 54 progresses
across the plough folder 78, the converging edge gradually extends
across more of the end of the smoking article 54, thus folding the
overhanging paper over along its whole length. In this manner, a
continuous fold is formed all around the circumference of the
tobacco rod and the overhanging paper is brought flat against the
end of the tobacco in the tobacco rod. When the smoking article 54
emerges from the end of the plough folder 78, its end is completely
covered by folded paper, provided that the original overhang was of
sufficient length.
[0098] FIG. 7 shows a schematic representation of a further example
of a folding apparatus. This is similar to that of FIG. 6, in that
it utilises a rotating drum 74 to roll smoking articles 54 over the
surface of a static rolling plate 76. In this example, however, the
plough folder is replaced with a series of teeth 80. Like the
plough folder, the teeth 80 extend inwardly from the surface of the
rolling plate 76 and have surfaces in a plane level with the end of
the tobacco in the tobacco rods of the smoking articles 54. Each
tooth 80 has an edge that begins on the surface of the rolling
plate 76 and converges towards the surface of the drum, so that the
far end of each tooth 80 extends at least half way across the space
between the rolling plate 76 and the drum 74. Thus, each tooth 80
may be thought of as an individual plough folder. However, the
length of each tooth in the direction of travel of the smoking
articles is less than the circumference of the smoking articles, so
each tooth 80 can only fold over a part of the overhanging foldable
paper. The next tooth 80 engages the overhang where the previous
tooth has stopped folding, and makes a new and separate fold that
overlaps the previous fold. Each tooth 80 makes a separate fold
which overlaps the preceding fold. Thus, there must be enough teeth
to fold over all of the overhanging paper, so the total length of
the teeth must be at least the circumference of the smoking article
54. This gives an iris-style fold, comprising the same number of
folds as there are teeth 80 on the rolling plate 76.
[0099] FIG. 8 shows a schematic end view of a smoking article
having its end closed with an iris fold. The five overlapping folds
have been formed in the order a to e, for example using the five
teeth 80 on the rolling plate 76 shown in FIG. 7.
[0100] FIG. 9 shows a schematic representation of a yet further
example of a folding apparatus that uses a rotating drum 74 and a
static rolling plate 76. In this example, each vacuum flute for
carrying a smoking article 54 has an associated cam folder 82. For
each flute, the cam folder 82 comprises a cam which is rotatably
mounted on the end face of the drum 74 in line with the flute such
that the cam provides a surface that extends beyond the edge of the
end face of the drum, over the smoking article 54 in the flute, the
surface being flush with the end of the tobacco rod of the smoking
article 54. The axis of rotation of the cam is parallel to that of
the drum 74, and, being a cam, the surface has an edge which is
eccentric with respect to the axis of rotation. Thus, as the cam
rotates, the edge of the surface gradually extends further and
further over the end of the tobacco rod. The maximum extent should
be at least half-way across the width of the smoking article.
[0101] When a smoking article 54 enters a flute on the drum 74, the
associated cam is in a position in which the cam surface does not
protrude beyond the edge of drum 74. When the smoking article
reaches the rolling plate 76, the cam folder is switched on, and
the cam surface begins to rotate. As the edge begins to protrude
past the edge of the drum 74, the edge engages with the overhanging
foldable paper and pushes it over against the end of the tobacco in
the tobacco rod. At the same time, the smoking article 54 is
rolling over the rolling plate 76, so that as the cam edge extends
further over the end of the tobacco rod, a new part of the overhang
is brought into engagement with the cam edge, to be pushed inwards
over the tobacco. The cam rotation is timed such that as the
smoking article 54 rotates once across the rolling plate 76, the
cam also rotates once so that the edge swings out over the end of
the tobacco rod, and then gradually recedes as the eccentricity of
the cam moves closer to the rotation axis again. These movements
combine to produce a continuous fold in the overhanging foldable
paper, all around the circumference of the smoking article. The
rotating cam works in a similar way to the smooth-edged plough
folder of FIG. 6, by providing a tapering edge that gradually
extends further and further across the end surface of the tobacco
rod as the smoking article rolls around, to produce a single
continuous fold.
[0102] The folding effect of the tooth-style folder of FIG. 7 may
also be replicated using cam folders. This can be achieved by
providing cams with stepped edges instead of the smooth profile
shown in FIG. 9. Each step in the edge produces a separate fold of
just part of the overhanging foldable paper, with successive folds
overlapping to produce a final iris fold.
[0103] FIG. 10 shows a schematic representation of a still further
folding apparatus that uses a rotating drum 74 in combination with
a rolling plate 76. In this example, the rolling plate 76 operates
in conjunction with a rotating threaded screw 84 to engage and fold
the overhanging paper. The threaded screw 84 is driven by motor 86
and arranged with its longitudinal axis, and hence also its axis of
rotation, substantially orthogonal to the axis of rotation of the
drum 74 and the longitudinal axes of the smoking articles 54
carried by the drum. The threaded screw 84 is further positioned so
that it extends largely along the extent of the rolling surface of
the rolling plate, and with the threaded surface in the same plane
as the ends of the tobacco rods of the carried smoking articles. In
this way, the threaded surface forms a surface flush with the ends
of the tobacco rods over which the tobacco surface can be moved to
fold over the overhanging paper, as with the flush surfaces in the
previous embodiments. To achieve folding, the threaded screw 84 is
rotated at the same time as the smoking article 54 rolls over the
surface of the rolling plate 76. The threads of the screw hence
come into contact with successive parts of the overhanging foldable
paper, engage therewith, and fold each part inwards against the end
of the tobacco rod. By matching the speed of rotation of the
threaded screw to the rolling speed of the smoking article, or
setting the speeds to be a ratio, the folds can be made neatly
adjacent and overlapping to form a tidy iris fold. The pitch of the
screw thread determines the number of folds.
[0104] FIG. 11 shows another example of a folding apparatus in
accordance with the invention that uses a rotating drum 74 to carry
smoking articles 54 past three folding devices to create three
folds. Two of the folding devices are a pair of rotating folders 88
which have a fixed location with respect to the drum 74, and are
arranged side by side substantially along a radius of the drum but
beyond the edge of the drum 74, to provide two surfaces flush with
the ends of the tobacco rods of the smoking articles 54. The
surfaces rotate about axes parallel to the rotation axis of the
drum, and have edges shaped such that the rotation brings the
surfaces into and out of the path of the smoking articles 54 as the
drum rotates. For example, the surfaces may be cams, so that the
eccentricity of the cam rotation gives a surface that in some
positions extends over part of the end of a smoking article, and in
some positions does not, because the edge is closer to the axis of
rotation of the cam. Alternatively, the surfaces may be centrally
mounted circular surfaces with a missing sector, such as a quarter,
as shown in the Figure. Thus, in some rotational positions, the
surface extends partially over the end of the tobacco rod, and in
other positions, the missing sector coincides with the tobacco rod
so that the surface does not extend over the end of the tobacco
rod. The two rotating surfaces of the rotating folders are arranged
to rotate in opposite directions, and in either of the above
examples of surface shape, the effect is to provide two surfaces
with leading edges that engage with adjacent parts of the
overhanging foldable paper as the surfaces rotate, further rotation
of the surfaces causing the surfaces to sweep over the end of the
tobacco rod and fold over the foldable paper to form first and
second folds. The folds are substantially along the two sides of
the smoking article with respect its direction of travel, but also
adjacent in a substantially V-shaped formation.
[0105] The rotational positions, directions of rotation and speeds
of rotation of the two rotating folders 88 are chosen such that a
smoking article can initially pass between them with no folding
(the surfaces are in positions in which they do not extend over the
ends of the tobacco rods). At a particular point, when the smoking
article 54 is in range of the folding surfaces when they are
rotated into position (approximately 54a in FIG. 11), the folders
88 rotate, the leading edges of the surfaces engage with the rear
of the overhanging foldable paper, and the surfaces sweep forwards
across the end of the tobacco rod to fold the two sides of the
overhanging paper flat against the tobacco. The surfaces need to be
rotating faster than the drum to achieve this so that the smoking
article 54 does not move out of range of the rotating folders 88
before folding is complete. Alternatively, the rotating drum 74 may
be halted while the rotating folders 88 rotate.
[0106] The two rotating folders 88 can be arranged as a pair, as in
FIG. 11, so that the first and second folds are formed
simultaneously. This is advantageous if the rotating drum is halted
for folding, as less time is needed to make these two folds.
However, the same folding effect can be achieved by positioning the
rotating folders 88 at different points around the drum 74.
[0107] The apparatus of FIG. 11 further comprises a third folder
90, which is a static tucker like the second folding device 58 in
FIG. 4. The third folder provides a surface fixed relative to the
drum, and as with previously described surfaces, arranged in the
same plane as the end of the tobacco in the tobacco rods. As the
smoking article having first and second folds approaches the third
folder 90, the edge of the surface engages the leading edge of the
overhanging foldable paper, and folds it flat against the tobacco
as the smoking article passes under the surface of the folder 90 to
create a third fold. Alternatively, a further rotating folder may
be used to make the third fold, having a surface with a suitably
shaped edge to sweep over the appropriate part of the overhanging
foldable paper as the smoking article is carried past.
[0108] FIG. 11A shows an end view of a smoking article with its end
closed with a three-way fold, such as may be formed with the
apparatus of FIG. 11, for example.
[0109] FIG. 12 shows a simplified schematic perspective view of
apparatus according to an embodiment of the invention that uses a
series of five rotating drums to apply a foldable paper to the end
of the smoking article, and then fold the overhanging foldable
paper over in a four-way envelope fold.
[0110] The rotating drums 100, 102, 104, 106, 108 are represented
with dotted lines only, for the sake of clarity. The drums are
arranged in sequence from right to left and positioned adjacent to
one another so that the smoking articles 54 carried thereon can be
transferred from a flute on one drum to a flute on the next drum by
appropriately timed switching of the vacuum suction. The first and
second drums 100 and 102 are used to apply a foldable paper 110 to
the end of each smoking article 54 in the same way as described
with reference to FIG. 2. The first drum 100 carries the smoking
articles 54 past a supply of glued foldable papers 110 so that each
smoking article 54 picks up a foldable paper 110. The second drum
102 carries the smoking articles 54 over a rolling plate (not
shown) so that the resulting rolling motion causes the foldable
paper 110 to be wrapped around the tobacco rod and stuck to the
cigarette paper (smoking article 54b).
[0111] After application of the foldable paper 110, the smoking
article is transferred from its flute on the second drum 102 to a
flute on the third drum 104 (smoking article 54c). Each flute on
the third drum is provided with a flute former, which is a
protrusion extending outwardly from the surface of the flute that
pushes against the overhanging foldable paper 110 as the smoking
article enters the flute, and hence folds the foldable paper 110
flush against the end of the tobacco rod as the smoking article
moves fully into its seat within the flute, if the smoking article
is appropriately positioned relative to the protrusion.
[0112] FIG. 13A illustrates a side view of the smoking article 54c
as it is beginning to enter a flute 112 on the third drum 104 (the
smoking article 54c moving into the flute 112 in the direction of
the arrow). The protrusion 114 pushes the overhanging foldable
paper 110 over into a folded position as the end of the tobacco rod
116 slides under the protrusion 114. This creates a first fold in
the foldable paper 110.
[0113] The smoking article 54 having a first fold in its foldable
paper 110 is then transferred to a flute in the fourth drum 106.
The flutes on the fourth drum 106 are provided with flute formers
or protrusions which act to create a second fold in the foldable
paper 110 as the smoking article 54d enters the flute, in the same
manner as for the third drum 104. Given that the first fold is made
at the side of the smoking article 54 closest to the centre of the
third drum 104 as the smoking article 54 enters the flute on the
third drum 104, the second fold is made opposite to the first fold
because the side of the smoking article 54 furthest from the centre
of the third drum 104 is the side of the smoking article 54 that
enters the flute on the fourth drum 106.
[0114] FIG. 13B shows a side view of the smoking article 54d as it
is beginning to enter a flute 112 on the fourth drum 106. The
protrusion 114 pushes the overhanging foldable paper 110 over into
a folded position as the end of the tobacco rod 116 slides under
the protrusion 114, to create a second fold opposite the first
fold.
[0115] The fourth drum 106 is also provided with a static rolling
plate (not shown) that operates to rotate the smoking articles by
approximately 90.degree. within the flutes (smoking article 54e).
This action brings the smoking articles in a position in which the
as yet unfolded parts of the overhanging foldable paper 110 are
arranged along the radius of the fourth drum 106. To facilitate the
rotation with the rolling plate, it may be necessary to arrange the
protrusions 114 on the fourth drum 106 to be retractable into a
position where they do not extend into the flutes and hence do not
become caught on the unfolded foldable paper as the smoking
articles 54 turn within the flutes.
[0116] More generally, the protrusions on both the third drum and
the fourth drum may be movable between an extended position in
which they act to fold the overlapping paper as the smoking article
enters the flute, and a retracted position in which they do not
protrude into the flute and hence do not impede future motion of
the smoking article, including rotation within the flute and
transfer from the flute. Movement between the two positions may be
timed to synchronise with the rotation of the various drums, to
achieve a smooth and continuous passage of the smoking articles
through the drum sequence. Alternatively, the protrusions on one or
both of the third and fourth drums may be static.
[0117] Finally, the smoking articles 54 are transferred to a fifth
drum 108, which carries the smoking articles 54f past a pair of
plough folders 118 which operate as the plough folders described
with regard to FIG. 4 to fold over the two remaining overhanging
parts of the foldable paper 110 to create third and fourth folds
opposite one another and orthogonal to the first and second
folds.
[0118] FIG. 14 shows a simplified schematic perspective view of
apparatus according to a further embodiment of the invention that
also uses a series of five rotating drums to apply a foldable paper
to the end of the smoking article, and then fold the overhanging
foldable paper over in a four-way envelope fold. In this example,
the first, second, third and fourth drums 100, 102, 104, 106
operate in the same way as for the embodiment of FIG. 12 to apply a
foldable paper 110 to each smoking article 54 and to create first
and second folds in the overhanging foldable paper 110 using
protrusions in the flutes of the third and fourth drums 104, 106.
Again, the fourth drum 106 has a fixed rolling plate that rotates
the smoking articles by 90.degree. before they are transferred to
the fifth drum 108.
[0119] The embodiment of FIG. 14 differs from that of FIG. 12 in
that the plough folders 118 of FIG. 12 are replaced by a pair of
reciprocating folders 120. These folders are two folding surfaces
in the plane of the end of the tobacco rods carried by the smoking
article 54 on the fifth drum 108 that can pivot between a first
position where they are both out of the path of the smoking
articles 54 so that a smoking article can pass between them with no
contact to the overhanging foldable paper, and a second position in
which they lie in the path of the smoking articles 54 so that the
ends of the tobacco rods pass flush with the folding surfaces. As
the folders 120 move from the first position to the second
position, the edges of the folding surfaces sweep across the end of
the tobacco rod, pushing the two remaining parts of the overhanging
foldable paper inwards to create the third and fourth folds.
[0120] FIG. 15 shows a simplified schematic perspective view of
apparatus according to a yet further embodiment of the invention
that uses a series of six rotating drums to apply a foldable paper
to the end of the smoking article and then fold the overhanging
foldable paper over into a four-way envelope fold. Once again, the
first, second, third and fourth drums 100, 102, 104, 106 operate in
the same way as for the embodiment of FIG. 12 to apply a foldable
paper 110 to each smoking article 54 and to create first and second
folds in the overhanging foldable paper 100 using protrusions in
the flutes of the third and fourth drums 104, 106. However, in this
example, there is no rolling plate associated with the fourth drum
106, so the smoking articles are not rotated in their flutes before
entering the flutes of the fifth drum 122.
[0121] Each flute of the fifth drum 122 is provided with a shaped
static folder 126 that is attached to the end surface of the drum
122 (only one shown). As with previously described folders, each
static folder offers a surface in the plane of the end of the
tobacco rods of the smoking articles held on the associated drum
against which the end of the tobacco rod slides with the result
that part of the overhanging foldable paper is pushed over and
folded flat against the end of the tobacco rod. In the present
example, after the first and second folds are formed, the two
remaining overhanging parts of the foldable paper 110 are located
at the side of the smoking articles with respect to the direction
in which the smoking articles enter the flutes of the fifth drum
122 (because of the lack of a rolling plate to turn smoking
articles on the fourth drum 106). Hence, the static folders 126 are
located to overhang a side of each flute, to fold in the
corresponding side of the overhanging foldable paper 110. The
static folders 126 are shaped so that they present an edge to the
incoming smoking articles that begins towards the outside of the
smoking article and converges towards the centre of the end of the
smoking article as the smoking article enters the flute. Hence the
static folders operate in a similar manner to plough folders, and
fold in a part of the overhanging foldable paper 110 that is at the
edge of the smoking article with respect to the forward direction
of movement of the smoking article as the smoking article enters
and moves into the flute. A third fold is thereby created that is
orthogonal to the first and second folds.
[0122] Similarly, the sixth drum 124 also has static folders 128
associated with each flute. The static folders 128 are located with
respect to the flutes so as to fold over the remaining part of the
overhanging foldable paper, thus creating a fourth fold opposite
the third fold.
[0123] In the embodiments of FIGS. 14 and 15, the protrusions on
the third and fourth drums may be static or movable, as described
with reference to FIG. 13.
[0124] FIG. 16A shows a cross-sectional side view of a further
embodiment of apparatus for folding the foldable paper, using
pincers. The apparatus 150 comprises a shaft 152 by which the
apparatus can be mounted on a rotatable drum, and a pincer
mechanism 154 mounted on one end of the shaft 150. The pincer
mechanism 154 is mounted so that it can move along the direction
defined by the length of the shaft 150. The pincer mechanism 154
comprises a cylindrical housing 156 sized to receive the end of a
smoking article, and a pair of pincers 158 mounted on opposite
sides of the housing 156. Each pincer 158 is formed from an
L-shaped member that is pivotably mounted on the housing 156 at the
angle between the two arms of the L-shaped member. Each pincer 158
is mounted such that one arm 160 of the L-shaped member forms a
pincer arm that extends generally longitudinally and terminates in
an inwardly facing jaw 162. The other arm 164 of the L-shaped
member forms a connecting arm that extends generally outwardly and
terminates in a connection point 166 by which the arm 164 is
connected to one end of a spring 168 which extends longitudinally.
The other end of the spring 168 is connected to a slidable collar
170 that encircles the housing 156 and can slide longitudinally
over part of the housing 156. The slidable collar 170 generally
occupies a retracted position (as shown in FIG. 16A) in which it is
drawn back away from the pincer jaws 162. In this position, the
tension of the springs 168 pulls on the connecting arms 164 of the
pincers 158, turning the pincers about the pivotal mounting so that
the jaws 162 are open.
[0125] FIG. 16B shows a plurality of pincer apparatus 150 mounted
on a rotatable drum 172. Each apparatus 150 is longitudinally
aligned with a vacuum flute 174 in the drum 172 and positioned at
the end of the vacuum flute 174 so that the apparatus 150 can
operate on a smoking article held in the vacuum flute 174. In use,
therefore, multiple smoking articles are transferred to the vacuum
flutes 174 of the drum 172 so that folding of the foldable paper
can be carried out on all the smoking articles together.
[0126] FIG. 16C shows a side view of the apparatus 150 in use in a
first step of folding. After a smoking article 54 is transferred to
a vacuum flute on the rotating drum, the pincer mechanism 154 moves
forward towards the smoking article 54, as shown by the arrow,
until the overhanging foldable paper 110 is received within the
jaws 162 of the pincers 158. The edge of the jaws 162 is aligned
with the end of the tobacco in the smoking article 54.
[0127] FIG. 16D shows a side view of the apparatus 150 in use in a
second step of folding. After alignment of the smoking article 54
and the pincers 158 as shown in FIG. 16C, the slidable collar 170
moves forward over the outside of the housing 156, towards the
pincers 158. This releases the tension in the springs 168 so that
the pincers 158 are free to pivot about the pivotal mountings. At
the same time, the edge of the slidable collar 170 comes into
contact with the connecting arms 164 of the pincers 158, and pushes
against them, which has the effect of pivoting the pincers 158 so
that the jaws 162 close towards each other, as indicated in FIG.
16D. The jaws 162 push opposite sides of the overhanging foldable
paper 110 inwards over the tobacco in the smoking article 54,
thereby creating opposite first and second folds of an envelope
fold. After folding, the slidable collar 170 retracts, allowing the
springs 168 to pull the jaws 158 open. Then the pincer mechanism
154 also retracts away from the smoking article to release it for
further processing.
[0128] After this folding stage, the smoking articles can be
transferred from the rotatable drum to apparatus for forming the
third and fourth folds. For example, a second rotating drum having
further pincer apparatus 150 can be provided, with an intermediate
stage, such as a rolling plate, for rotating the smoking articles
so that they are transferred onto the second drum with the
overhanging foldable paper in the correct orientation for folding
with the pincer apparatus. Alternatively, the further pincer
apparatus could be mounted with the pincers in an orthogonal
position to those of the first rotatable drum, so that there is no
need to rotate the smoking articles. Otherwise, any other folding
apparatus can be used to create opposite third and fourth folds
orthogonal to the first and second folds, to give an envelope
fold.
[0129] FIG. 17 shows a schematic side representation of a further
embodiment of apparatus for applying the foldable paper to the
smoking article, and also for folding the overhanging foldable
paper. The apparatus does not include any of the rotating drums
described thus far. Instead, the apparatus comprises a lower
horizontal surface 140 and an upper horizontal surface 143 spaced
above the lower surface 140 by an amount slightly less than the
width of a smoking article 54, so that a smoking article 54
introduced into the space experiences an interference fit. The
upper surface comprises an endless belt 143 rotating about two
horizontally arranged rollers 144. A smoking article 54 carrying a
glued foldable paper 110 adhered at its leading edge only to the
cigarette paper of the smoking article 54, is introduced into the
space between the upper surface 142 and the lower surface 143. The
foldable paper 110 may have been prepared and applied to the
smoking article 54 by any convenient method, including the vacuum
cutting drum and associated equipment described with respect to
FIG. 2. When the smoking article 54 enters the space between the
upper surface 142 and the lower surface 140, the motion of the belt
143 forming the upper surface 142 in conjunction with the
interference fit causes the smoking article 54 to be rolled over
the lower surface 140. This rolling motion in turn causes the
smoking article 54 to roll over the foldable paper 110 that it is
carrying, which is hence wrapped around the outside of the smoking
article 54 and adheres to the cigarette paper because of the glue
applied to it. In this way, the smoking article is provided with
its overhanging foldable paper.
[0130] The lower surface 140, at a point downstream from where the
smoking article 54 enters the space between the surfaces 140, 142
sufficient to allow the foldable paper 110 to be wrapped around the
smoking article 54, is provided with a series of upstanding teeth
146. Each tooth 146 provides a surface that flush with the end of
the tobacco rod of the smoking article 54. As the smoking article
54 continues to roll over the lower surface 140, the teeth 146 in
turn engage a part of the overhanging foldable paper and push it
over against the end of the tobacco rod to create a fold, in a
similar manner to the folding teeth described with respect to FIG.
7. Each tooth creates one fold, to give a overlapping iris-style
fold.
[0131] The teeth 146 may be omitted from the apparatus so that it
just provides the function of wrapping the glued foldable paper 110
around the smoking article 54. Also, the lower surface 140 may be a
fixed surface, or it may comprise a rotating endless belt 143
similar to that of the upper surface 142 that rotates at a
different speed or direction to the upper surface belt 143 so as to
provide the required rolling of the smoking article 54. Further,
the moving upper surface may be provided by components alternative
to an endless belt rotating on rollers. Any combination of suitable
spaced upper and lower surfaces that produce the required relative
motion to roll the smoking article can be employed. Additionally,
the rolling can be used to carry the smoking article past folding
devices other than the teeth 146 can be used, for example a plough
folder similar to that in FIG. 6.
[0132] Further configurations of fold can be employed by adapting
any of the above-described apparatus (or using entirely different
apparatus) to fold the foldable paper other than into an envelope
fold, an iris fold or a three-way fold.
[0133] FIG. 18A shows an end view of a smoking article having
foldable paper that has been closed over the tobacco by the simple
technique of crushing the foldable paper inwards without making
distinct individual folds. A suitably configured apparatus may
crush the paper such that an embossed pattern or design is applied
to the paper end.
[0134] FIG. 18B shows an end view of a smoking article in which the
foldable paper has been folded using a pinch and twist fold, in
this case with three folds. The overhanging foldable paper is
pinched into a point with a plurality of folds, three in this
example. The folds are then twisted round to lay flat against the
end surface of the smoking article.
[0135] FIG. 18C shows an end view of a smoking article with a
foldable paper that has been folded using a two-way fold with
subsequent trimming of the overhanging wings. Two opposite sides of
the foldable paper are folded inwards, as for the two initial folds
of an envelope fold. The two remaining parts of the paper are then
folded outwards into the position shown by the dotted lines
(instead of inwards as for an envelope fold), before being trimmed
off. This gives a clean one-line appearance to the end of the
smoking article.
[0136] If desired, a further processing step can be added to any
technique used to fold over the overhanging foldable paper,
including all the above techniques. It may be found that after
folding, the foldable paper springs slightly open and away from the
flush folded position in which the folds lie flat against the end
of the tobacco rod. This can be addressed by pressing slightly into
the folded end with a pin or rod that has a diameter less than that
of the smoking article. The pin is moved in towards the end of the
smoking article along the direction of the longitudinal axis of the
smoking article, and by pressing inwards, the folded paper is
depressed beyond the flush folded position (since the underlying
tobacco will yield slightly under the applied pressure of the pin)
and inverted or crushed to a small amount. This inversion has been
found to be sufficient to hold the various folds in place better
than folding that is not followed by pressing with a pin. This is
preferable to holding the folds in place with adhesive, since it is
desirable to minimise the amount of adhesive used in a smoking
article. Also, pressing the end of the smoking article with a pin
is likely to be a simpler process than applying adhesive to the
various folds or parts of the overhanging paper at the relevant
times, and also does not require any on-going supply of
materials.
[0137] Any practical method and apparatus may be employed to
achieve the pressing. For example, a simple reciprocating pin
mounted on a mechanism that can move it into the pressing position
and out again could be used, with each smoking article held
stationary while the pin moves. However, this will be a relatively
slow step in a process which can otherwise be implemented with
continuous motion of the smoking articles (such as with the
apparatus of FIG. 12, for example). This therefore proposed that
the pressing pin be movable along the travel path of the smoking
articles so the pressing can be performed without halting the
smoking articles.
[0138] One way of achieving this it to utilise a swash plate, which
is a known apparatus for use with rotating drums for carrying
smoking articles: The swash plate comprises a disk in the form of a
circular rim portion having a flat face, the rim being connected to
a central hub by a plurality of springs arranged like the spokes of
a wheel. The swash plate is rotatably mounted with its axis of
rotation coincident with the axis of rotation of a rotating drum,
and its flat face substantially parallel with the end face of the
drum. In use, the swash plate is advanced towards the drum while
both rotate in the same direction, and the flat face pushes against
the ends of smoking articles carried by the drum to bring them all
into alignment in the longitudinal direction, so that the ends are
all positioned in a chosen plane. The spring-mounting of the rim
allows any initial unevenness in the alignment of the smoking
articles to be accommodated without any individual smoking article
receiving significantly more pressure than the others; this reduces
damage to the smoking articles. Further, the rotation of the swash
plate in time with that of the drum avoids sideways forces (drag)
on the smoking articles which would also cause damage.
[0139] To implement pressing into the end of folded paper with a
pin according to the present embodiment, it is proposed that a
swash plate be provided with a plurality of pins, one pin aligned
with each flute on the associated rotating drum in an appropriate
position to press into the centre of the end of the smoking article
held in the flute. The swash plate is moved in towards the rotating
drum by a sufficient distance to press the pins into the folded
paper by the required amount, and the rotation of the swash plate
and its spring-mounting allow the pins to be brought to bear on the
smoking articles without sideways drag or uneven pressure between
smoking articles.
[0140] FIG. 19A shows a schematic representation of a side view of
a rotating drum with an associated pin-bearing swash plate. The
drum 130 carries a plurality of smoking articles in the flutes
around its circumference, and the swash plate 132 is mounted to
rotate about the same axis as the drum, and at the same speed. A
plurality of pins 134, aligned with the flutes and the smoking
articles 54, are arranged on the flat face of the swash plate 132,
extending from the flat face towards the end surface of the drum
130. The drum 130 and the swash plate 134 rotate together, as
indicated by the curved arrows in FIG. 19A, and the swash plate 134
moves in towards the drum by action of a bearing 133 which moves
the plate 134 towards the drum 130, as indicated by the straight
arrow. The pins 134 press into the ends of the smoking articles 54,
and when they have protruded into the smoking articles 54 by a
sufficient distance to invert the folded paper by the require
amount to inhibit unfolding, the swash plate 132 is retracted away
from the drum 130.
[0141] FIG. 19B shows a schematic representation of an alternative
apparatus for pressing pins into the folded paper. The apparatus
comprises a rotating drum 130 carrying a plurality of smoking
articles 54 in flutes around its circumference, as in FIG. 19B. In
this example, however, the pins 134 extend radially outwards from
the surface of a second rotatable drum or disc 135 which is
arranged with its axis of rotation orthogonal to that of the
rotating drum 130 carrying the smoking articles 54. The pins 134
lie in a plane tangential to the rotating drum 130 so that the
rotation of the disc 135 together with the rotation of the drum 130
bring each pin 134 in turn into contact with the end of a smoking
article 54, the spacing of the pins 134 and the smoking article 54
and the speed of rotation of the drum 130 and the disc 135 being
selected accordingly. The disc 54 is spaced from the drum 130 by a
distance to allow each pin 134 to protrude slightly into the folded
paper to produce the required pressing effect, before being
withdrawn as the rotations move the pin and the smoking article
apart. The relative rotating motion of the drum 130 and the disc
135 bring the pins 134 to bear on the smoking articles 54 with
little or no sideways drag.
[0142] FIG. 20 shows a schematic cross-sectional view through the
end of a smoking article 54 with a pin 134 on a swash plate 132 or
disc/drum 135 bearing on the folded paper 110 that covers the end
of the tobacco in the smoking article 54, so as to slightly depress
and invert the folded paper 110.
[0143] In the event that it is acceptable to use adhesive to secure
the folds of the folded end in place, the foldable paper can have a
self-adhesive format. One or more areas of self-adhesive glue can
be provided on the overhanging part of the foldable paper
(preferably before it is applied to the smoking article). Depending
on the adhesive type, the act of folding may be sufficient to cause
the foldable paper to adhere to itself. Otherwise, an adhesive that
requires the application of heat and/or pressure can be used. After
folding, the folds can be pressed with pins using any of the pin
arrangements described above. The pins may be heated if the
adhesive is heat-activated, for example using electrical heating
elements within the pins. If it is not necessary that the folds be
pressed inwards by pins, the ends of the smoking articles may be
contacted with a heated flat plate or plates (such as a heated
swash plate) to set the adhesive.
[0144] The various folding techniques discussed above may be
implemented using an overhang of foldable paper that has a straight
edge, i.e. before folding the foldable paper extends beyond the end
of the tobacco rod by the same amount at all points around the
circumference of the smoking article. In many cases, this will give
an acceptable appearance to the finished folded end. Optionally,
however, the edge of the foldable paper may be shaped. This can be
used to reduce the amount of paper that has to be folded over the
end of the tobacco rod, by removing paper in those areas where two
or more layers of paper would otherwise overlap. The resulting
folded end may be easier to light, owing to the reduced amount of
paper covering the tobacco, and may have an improved appearance, or
a particular desired appearance.
[0145] A foldable paper with a shaped edge may be more easily
implemented with techniques that apply the foldable paper to the
smoking articles by wrapping individual pieces of foldable paper
around individual smoking articles, as in FIG. 2, for example. The
process of applying the foldable paper described with respect to
FIG. 3 may also be used to provide a shaped edge, but two cutting
stages will probably be required, one using a shaped blade to
provide the shaped edge to the overhanging foldable paper, and one
using a straight blade to provide a straight edge to the foldable
paper at the opposite end of the tobacco rod.
[0146] FIG. 21 shows some useful shapes for shaped edge foldable
papers: A: scalloped edge; B: castellated edge; C: edge with
extending segment shapes, curved to match the curvature of the end
of the smoking article. The number of scallops, segments, etc, will
depend on the number of folds to be used. Edges with other shapes
may be also be used.
[0147] FIG. 22 shows a plan view of an example of a foldable paper
110 to which adhesive has been applied, for example by the
apparatus of FIG. 2. The foldable paper 110 is sized to extend a
short distance along the length of a tobacco rod. Its shorter sides
are the dimension that extends along the tobacco rod and beyond its
end to form the overhang, and its longer sides are the dimension
that encircles the tobacco rod. The adhesive is applied in three
areas. Area A extends across the full width of the paper 110 in the
encircling direction, and about halfway up the length of the paper
110. This is the area that contacts the cigarette paper of the
tobacco rod, so the foldable paper will adhere to the cigarette
paper all around its circumference, with no adhesive from this area
being on the overhanging foldable paper. Area B is a narrow strip
of adhesive running along a length edge of the paper 110. This
corresponds to the area of overlap when the paper 110 is wrapped
around a tobacco rod, and sticks the overlapping edges of the paper
together to form a tube extending beyond the end of the tobacco
rod. Area C is a narrow strip of adhesive running across the width
of the paper close to the edge that will become the far end of the
overhang. This sticks the various folds in place as they are
created by the folding devices. The adhesive in area C can be
omitted if the folds stay sufficiently in place without it, or if
pressing in the folded paper, for example with a pin as in FIGS.
19A, 19B and 20 provides adequate holding. Similarly, the areas A
and B may have adhesive applied in other distributions, such as
spots or stripes rather than the continuous distribution of FIG.
22.
[0148] Alternatively, the folds may be secured in place using
adhesive that is applied during the folding process. For example,
for an envelope fold such as shown in FIG. 5D, the first two folds
may be made, following which adhesive is applied to the two
opposite remaining unfolded parts of the overhanging paper before
they are folded over. The adhesive then holds these two outside
folds in place, thereby securing the folded end as a whole.
However, for any fold arrangement, adhesive may be applied to any
or all of the unfolded flaps or portions before they are folded
over. To achieve this, a gluing unit may be positioned adjacent to
the apparatus carrying the smoking articles during the folding
process. For example, the gluing unit may include one or more glue
guns operable to apply a small amount of adhesive to each flap
before folding. Adhesive may be applied to two or more flaps or
portions simultaneously. In the above example of the envelope fold,
two glue guns may simultaneously apply glue to the two opposite
unfolded parts. As another example, the gluing unit may comprise a
gravure-style gummer timed to operate in synchronism with the
operation of the folding apparatus.
[0149] Once the folded end of the smoking article has been
completed (possibly including gluing and/or pressing the folds
inwards as described above), it may be desirable to check the
quality of the folded end, so that smoking articles with folds
which are below standard can be ejected from the production line.
Quality checking can be achieved by including an inspection system
at the end of folding apparatus; this may be, for example a
camera-based inspection system. One or more cameras can capture
images of each folded end, and provide a signal to the apparatus to
reject the smoking article if a defective fold is detected.
Detection may be, for example, by a pattern recognition or image
comparison technique, in which the captured images are compared
with stored images of non-defective folded ends. If there is an
insufficient match between the captured and stored images, a
rejection signal is generated and sent to the apparatus to reject
the relevant smoking article. Any rejection system can be used,
depending on the way in which the smoking articles are carried past
the inspection system. For example, if the smoking articles are
carried in the flutes of a rotating vacuum drum, the vacuum in a
flute carrying a defective smoking article can be switched off,
thereby allowing the smoking article to drop away from the
drum.
[0150] FIG. 23 shows a simplified schematic view of an inspection
system, seen from above. In this example, a rotating drum 200
carries a plurality of smoking articles 202 with folded ends past
an inspection system 203. The inspection system 203 comprises a
first camera 206 and a second camera 208 arranged next to the drum
200, and both connected to a control unit 210. The first camera 206
is positioned to record an end view of the folded end of each
smoking article 202, as the smoking articles 202 are carried past
the camera 206 by the rotation of the drum 200. The second camera
208 is positioned to record a side view of each folded end. In this
way, a large number of defects in the folded end can be picked up,
including defects in the attachment of the overhanging paper to the
smoking article. However, an inspection system may include just one
camera, arranged to capture an end view or a side view, or a view
intermediate between the side and the end.
[0151] The images from the first camera 206 and the second camera
208 are sent to the control unit 210 for processing, such as by
comparison with stored images of non-defective folded ends. In the
event that the processing detects a defect, the control unit 210
generates a reject signal, which is sent by a control line 212 to a
controller 204 of the rotating drum 200 to cause operation of a
rejection mechanism that rejects the defective smoking article. The
images should be captured in a timed manner with regard to the
rotation of the drum, so that the rejection mechanism operates on
the correct smoking article.
[0152] Any of the techniques described herein for providing a
smoking article with an overhanging foldable paper may be combined
with any of the techniques described herein for folding the
overhanging foldable paper. Moreover, any of the described
techniques may be combined with techniques similar to those
described to achieve the described end result of a smoking article
having an overhanging foldable paper that is folded over to cover
the tobacco. Further, techniques similar to those described may be
used to achieve the described end result. In addition, the
techniques described herein for folding the overhanging foldable
paper may alternatively be used to fold overhanging paper that is
not a separately applied foldable paper such as that described
herein, but is instead an extending portion of the cigarette paper
that wraps the tobacco of the tobacco rod.
[0153] When considering the various embodiments of apparatus
described herein, components for adhering the foldable paper to the
smoking articles may be thought of as a first sub-apparatus,
components for folding the overhanging foldable paper may be
thought of as a second sub-apparatus, components for pressing pins
into the folded paper to enhance the folding effect may be thought
of as a third sub-apparatus, and any further components employed to
attach filter units to any smoking articles that are only partially
complete when the foldable paper is adhered may be thought of as a
fourth sub-apparatus. To increase the speed of production, the
number of first and/or second sub-apparatuses in the apparatus as a
whole may be increased. For example, two folding apparatuses or two
apparatuses for adhering the foldable paper may be arranged in
parallel to supply twice the quantity of smoking articles to the
downstream parts of the apparatus.
References
[0154] 1. U.S. Pat. No. 1,164,118 [0155] 2. U.S. Pat. No. 501,498
[0156] 3. U.S. Pat. No. 903,101 [0157] 4. U.S. Pat. No. 3,208,458
[0158] 5. GB 278,534
* * * * *