TECHNICAL FIELD
[0001] The present invention relates to a packing method employing non-dry, re-stick glue.
BACKGROUND ART
[0002] Rigid, hinged-lid packets of cigarettes are currently the most widely marketed, by
being easy to produce and easy and practical to use, and by effectively protecting
the cigarettes inside.
[0003] In addition to the above rigid, hinged-lid packets of cigarettes, rigid slide-open
packets have been proposed comprising two partly separable containers, one inserted
inside the other. In other words, a rigid, slide-open packet of cigarettes comprises
an inner container, which houses a foil-wrapped group of cigarettes and is housed
inside an outer container to slide, with respect to the outer container, between a
closed configuration, in which the inner container is inserted inside the outer container,
and an open configuration, in which the inner container is expelled from the outer
container.
[0004] A rigid, hinged-lid, slide-open packet of cigarettes has also been proposed in which
the inner container (or outer container) has a hinged lid, which rotates between a
closed position and an open position closing and opening an open top end of the inner
container. The lid has a connecting tab connected at one end to the lid, and at the
other end to the outer container (or inner container), to 'automatically' rotate the
lid (i.e. without the user having to touch the lid) as the inner container slides
with respect to the outer container.
[0005] In currently used methods of producing hinged-lid, slide-open packets of cigarettes,
an outer blank for forming the outer container has the connecting tab, to which glue
is applied; and, when the inner container is fed onto the outer blank, a rear wall
of the inner container rests on the previously gummed connecting tab (i.e. to which
glue has been applied) to glue the connecting tab to the rear wall of the inner container.
To ensure the connecting tab is glued both firmly and quickly to the rear wall of
the inner container, the connecting tab is applied with both a weak, fast-setting
first permanent glue (typically fast-drying, hot-melt glue), and a stronger, slow-setting
second permanent glue (typically cold, vinyl-based glue that dries very slowly but,
when dry, provides for extremely firm grip). Because the fast-setting first permanent
glue dries so fast, however, it must be applied close to where the inner container
engages the outer blank (i.e. where the rear wall of the inner container rests on
the connecting tab on the outer blank). This poses serious packing machine design
problems, due to the difficulty of applying glue to the connecting tab close to where
the inner container engages the outer blank, on account of the connecting tab, in
the area referred to, being located inside a 'cradle' formed by various previously
folded panels on the outer blank (i.e. the connecting tab is covered by various previously
folded panels on the outer blank, and therefore difficult to reach).
DESCRIPTION OF THE INVENTION
[0006] It is an object of the present invention to provide a packing method designed to
eliminate the above drawbacks, and which, in particular, is cheap and easy to implement.
[0007] According to the present invention, there is provided a packing method as claimed
in the accompanying Claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] A number of non-limiting embodiments of the present invention will be described by
way of example with reference to the accompanying drawings, in which:
Figure 1 shows a front view in perspective of a rigid, hinged-lid, slide-open packet
of cigarettes in a closed configuration;
Figure 2 shows a front view in perspective of the Figure 1 packet of cigarettes in
an open configuration;
Figure 3 shows a top plan view of the Figure 1 packet of cigarettes in an open configuration;
Figure 4 shows a front view in perspective of an outer container of the Figure 1 packet
of cigarettes;
Figure 5 shows a front view in perspective of an inner container of the Figure 1 packet
of cigarettes without the group of cigarettes and with a connecting tab;
Figure 6 shows a plan view of an inner blank from which to form an inner container
of the Figure 1 packet of cigarettes;
Figure 7 shows a plan view of an outer blank from which to form an outer container
of the Figure 1 packet of cigarettes;
Figure 8 shows a schematic in perspective of a packing machine, in accordance with
the present invention, for producing the Figure 1 packet of cigarettes;
Figure 9 shows a schematic in perspective of a packing wheel of a second packing unit
of the Figure 8 packing machine;
Figure 10 shows a plan view of the Figure 7 outer blank partly folded and glued just
prior to being fed to the Figure 9 packing wheel.
PREFERRED EMBODIMENTS OF THE INVENTION
[0009] Number 1 in Figures 1 and 2 indicates as a whole a rigid, slide-open packet of cigarettes,
which opens in a translatory (linear) movement.
[0010] The Figure 1 packet 1 of cigarettes comprises a wrapped, i.e. foil-wrapped group
2 of cigarettes (shown in Figure 2). Packet 1 of cigarettes also comprises a rigid
inner container 3 actually containing the wrapped group 2 of cigarettes; and a rigid
outer container 4, which houses inner container 3 to allow inner container 3 to slide
in a translatory movement, with respect to outer container 4, between a closed configuration
(Figure 1), in which inner container 3 is inserted fully inside outer container 4,
and an open configuration (Figure 2), in which inner container 3 is expelled from
outer container 4 to allow access to wrapped group 2 of cigarettes.
[0011] As shown in Figure 5, inner container 3 is parallelepiped-shaped, and comprises a
bottom wall 5; an open top end 6 opposite bottom wall 5; a front wall 7 and rear wall
8 opposite and parallel to each other; and two parallel lateral walls 9 interposed
between walls 7 and 8.
[0012] As shown in Figure 4, outer container 4 has an open top end 10; and a lid 11 hinged
to outer container 4 along a hinge 12 to rotate, with respect to outer container 4,
between an open position (Figures 2, 3 and 4) and a closed position (Figure 1) respectively
opening and closing open top end 10 of outer container 4 and, at the same time, also
open top end 6 of inner container 3. Outer container 4 is parallelepiped-shaped, and
comprises a bottom wall 13 opposite open top end 10; a front wall 14 and rear wall
15 opposite and parallel to each other; and two parallel lateral walls 16 interposed
between walls 14 and 15.
[0013] Lid 11 comprises a top wall 17 which closes open top end 10 of outer container 4
(and, at the same time, open top end 6 of inner container 3) when the lid is closed.
Top wall 17 of lid 11 is 'flat' (i.e. is formed from one cardboard panel or a number
of compacted cardboard panels, and is therefore solid). When lid 11 is closed, top
wall 17 of lid 11 is flush with the top edges of walls 14, 15 and 16 of outer container
4.
[0014] In a preferred embodiment, rear wall 8 of inner container 3 is connected to top wall
17 of lid 11 by a connecting tab 20 to rotate lid 11 'automatically' (i.e. without
the user having to touch lid 11) as inner container 3 slides with respect to outer
container 4. In other words, by means of connecting tab 20 connecting top wall 17
of lid 11 mechanically to rear wall 8 of inner container 3, inner container 3, as
it slides with respect to outer container 4 from the closed to the open configuration,
pushes lid 11 from the closed to the open position 'automatically' (i.e. without the
user having to touch lid 11); and similarly, as inner container 3 slides with respect
to outer container 4 from the open to the closed configuration, lid 11 is drawn by
inner container 3 from the open to the closed position 'automatically' (i.e. without
the user having to touch lid 11). The user therefore need simply exert sufficient
thrust to slide inner container 3 with respect to outer container 4, without having
to touch lid 11, which is rotated 'automatically'. Preferably, connecting tab 20 is
connected seamlessly to lid 11, and is glued to rear wall 8 of inner container 3.
[0015] As shown in Figures 1, 2 and 4, lateral wall 16 of outer container 4 has a through
window 21 allowing access to underlying lateral wall 9 of inner container 3 facing
lateral wall 16 of outer container 4, to exert thrust on inner container 3 to move
it between the closed and open configurations. In other words, to use packet 1 of
cigarettes, the user holds outer container 4 with one hand and, with the thumb of
the same hand, pushes on lateral wall 9 of inner container 3 through window 21 in
lateral wall 16 of outer container 4, to exert thrust on inner container 3 and slide
it with respect to outer container 4.
[0016] Containers 3 and 4 of the Figure 1-5 packet 1 of cigarettes are formed from corresponding
blanks 22 and 23 as shown in Figures 6 and 7. Among other things, each blank 22, 23
comprises a number of parts, which are indicated, where possible, using the same reference
numbers, with superscripts, as for the corresponding walls of respective container
3, 4.
[0017] With reference to Figure 6, inner blank 22 has two longitudinal fold lines 24, and
a number of transverse fold lines 25 which define, between the two longitudinal fold
lines 24, a panel 7' forming front wall 7 of inner container 3; a panel 5' forming
bottom wall 5 of inner container 3; and a panel 8' forming rear wall 8 of inner container
3. Panel 8' is connected along a transverse fold line 25 to a reinforcing panel 8",
in turn connected along a transverse fold line 25 to a further reinforcing panel 8"'.
Reinforcing panels 8" and 8"' are folded 180° about respective transverse fold lines
25 and glued onto an inner surface of panel 8' to thicken (reinforce) rear wall 8.
A different embodiment, not shown, has no reinforcing panels 8" and 8"'.
[0018] Panel 7' has two lateral wings 9', which form respective outer portions of lateral
walls 9, are located on opposite sides of panel 7', and are separated from panel 7'
by longitudinal fold lines 24. Panel 8' has two lateral wings 9", which are glued
to corresponding wings 9', form respective inner portions of lateral walls 9, are
located on opposite sides of panel 8', and are separated from panel 8' by longitudinal
fold lines 24. Each lateral wing 9" of panel 8' has a tab 26 separated from respective
lateral wing 9" by a transverse fold line 25.
[0019] With reference to Figure 7, outer blank 23 has two longitudinal fold lines 27, and
a number of transverse fold lines 28 which define, between the two longitudinal fold
lines 27, a panel 17' forming top wall 17 of lid 11; a panel 15' forming rear wall
15 of outer container 4; a panel 13' forming bottom wall 13 of outer container 4;
and a panel 14' forming front wall 14 of outer container 4.
[0020] Panel 17' is connected along a transverse fold line 28 to connecting tab 20, which
comprises three panels 20', 20", 20"' separated by respective transverse fold lines
28. Panel 20' of connecting tab 20 is glued to an inner surface of top wall 17 of
lid 11 (i.e. to an inner surface of panel 17'), and panel 20"' of connecting tab 20
is glued to an outer surface of rear wall 8 of inner container 3 (i.e. to an outer
surface of panel 8').
[0021] Panel 14' has two lateral wings 16', which form respective outer portions of lateral
walls 16, are located on opposite sides of panel 14', and are separated from panel
14' by longitudinal fold lines 27. Panel 15' has two lateral wings 16", which are
glued to corresponding wings 16', form respective inner portions of lateral walls
16, are located on opposite sides of panel 15', and are separated from panel 15' by
longitudinal fold lines 27. Each lateral wing 16" of panel 15' has a tab 29 separated
from respective lateral wing 16" by a transverse fold line 28.
[0022] Figure 8 shows a schematic of a cigarette packing machine 30 for producing packets
1 of cigarettes. Packing machine 30 comprises, in succession, a packing unit 31 for
forming wrapped groups 2 of cigarettes; a packing unit 32 for forming inner containers
3 by folding inner blanks 22 about corresponding wrapped groups 2 of cigarettes; a
packing unit 33 for forming outer containers 4 (and so completing packets 1 of cigarettes)
by folding outer blanks 23 about corresponding inner containers 3; and, finally, a
processing unit 34, which receives packets 1 of cigarettes from packing unit 33 and
opens (i.e. slides inner container 3 for the first time with respect to outer container
4, to partly expel inner container 3 and so rotate lid 11 into the open position)
and closes each packet 1 of cigarettes.
[0023] As shown in Figure 9, packing unit 33 comprises a packing conveyor 69 with a number
of packing pockets 70, each for housing an outer blank 23 and corresponding inner
container 3, and for feeding outer blank 23 and inner container 3 along a packing
path P4 extending between an input station S8 and an output station S10.
[0024] Packing unit 33 preferably comprises a packing conveyor (not shown) for partly prefolding
outer blanks 23 and feeding the pre-folded outer blanks 23 to packing conveyor 69.
A prefolded outer blank 23 (i.e. as it is fed to packing conveyor 69) is shown in
Figure 10, in which tab 20 is folded 180° (about corresponding transverse fold line
28 connecting tab 20 to panel 17'), panels 20' and 20" are superimposed on the inner
surface of panel 17', and panel 20"' contacts the inner surface of panel 15'. As stated,
only panel 20' is glued to panel 17'.
[0025] At input station S8, a partly prefolded outer blank 23 is fed into a packing pocket
70 so as to further fold outer blank 23. At a feed station S9 between input station
S8 and output station S10, an inner container 3 is fed into a packing pocket 70 and
onto the previously inserted outer blank 23. More specifically, rear wall 8 of inner
container 3 is positioned resting on panel 15' of outer blank 23. At output station
S10, outer container 4 (formed by folding outer blank 23 about inner container 3)
is expelled from packing pocket 70 and fed to processing unit 34.
[0026] At input station S8, a folding device 71 folds tabs 29 of outer blank 23 ninety degrees
(about corresponding transverse fold lines 28) with respect to wings 16", and then,
by inserting outer blank 23 inside packing pocket 70, folds panel 13' ninety degrees
(about corresponding transverse fold line 28), and folds the two wings 16" ninety
degrees (about corresponding longitudinal fold lines 27, while panel 17' of outer
blank 23 remains coplanar with panel 15'). In other words, after tabs 29 are folded
90°, insertion of outer blank 23 inside packing pocket 70 folds panel 13' and the
two wings 16" ninety degrees (while panel 17' of outer blank 23 remains coplanar with
panel 15'). Between feed station S9 and output station S10, a folding device 72 folds
panel 17' of outer blank 23 (i.e. lid 11) 90° (about corresponding transverse fold
line 28) with respect to panel 15', and at the same time slides inner container 3
axially with respect to outer blank 23 (as explained more clearly below). Directly
downstream from folding device 72, a folding device 73 folds panel 14' ninety degrees
(about corresponding transverse fold line 28). Folding outer blank 23 is completed
at output station S10 as outer container 4 is expelled from packing pocket 70: as
outer container 4 is expelled, a folding device 74 folds wings 16' ninety degrees
(about corresponding longitudinal fold lines 27) onto wings 16" to form lateral walls
16 of outer container 4. A gumming device (not shown) is preferably provided directly
upstream from folding device 74 to deposit glue between wings 16' and 16" just before
wings 16' are folded.
[0027] In a preferred embodiment shown in Figures 8 and 9, packing conveyor 69 is defined
by a wheel which rotates in steps about a central horizontal axis of rotation 75,
so packing path P4 is circular and extends from input station S8 to output station
S10.
[0028] Upstream from input station S8 of packing conveyor 69, a gumming device 77 deposits
glue between tabs 29 and panel 13' of outer blank 23. Gumming device 77 also deposits
glue 78 and glue 79 (Figure 10) onto panel 20"' of connecting tab 20 previously folded
onto panel 15' when partly prefolding outer blank 23. Glue 78 and glue 79 glue rear
wall 8 of inner container 3 to connecting tab 20 (i.e. to panel 20"' of connecting
tab 20) as inner container 3 is fed onto panel 15' of outer blank 23 at feed station
S9 of packing conveyor 69.
[0029] As stated, gumming device 77 deposits glue 78 and glue 79 simultaneously onto panel
20"' of connecting tab 20 previously folded onto panel 15'. Glue 78 and glue 79 glue
rear wall 8 of inner container 3 to connecting tab 20 (i.e. to panel 20"' of connecting
tab 20) as inner container 3 is fed onto panel 15' of outer blank 23 at feed station
S9 of packing conveyor 69. Glue 78 is permanent, drying glue, i.e. a certain length
of time after it is deposited, the volatile components of glue 78 evaporate to form
a permanent connection that can only be separated by irreparably tearing the connection
apart; whereas glue 79 is non-dry, re-stick glue, i.e. even a long time after it is
deposited, the characteristics of glue 79 remain unchanged, allowing the glued parts
to be separated and stuck back together repeatedly. Preferably, permanent, drying
glue 78 is a cold, vinyl-based glue.
[0030] In a preferred embodiment, non-dry, re-stick glue 79 is deposited far from a hinge
12' of connecting tab 20 (hinge 12' of connecting tab 20 is defined by the transverse
fold line 28 separating panels 20" and 20"'), whereas permanent, drying glue 78 is
deposited close to hinge 12' of connecting tab 20, so that, as folding device 72 folds
lid 11, non-dry, re-stick glue 79 is subjected to shear (i.e. greater) stress, while
permanent, drying glue 78 is subjected to tensile (i.e. less) stress. Because non-dry,
re-stick glue 79 is capable of achieving maximum grip much faster (practically instantaneously),
it is important that it be subjected to the greater stress; and, similarly, it is
important that permanent, drying glue 78 be subjected to less stress, by taking a
relatively long time to achieve adequate grip.
[0031] In a preferred embodiment, the above combination of permanent, drying glue 78 and
non-dry, re-stick glue 79 is not limited to the particular case described, but may
be used to advantage in any application involving gluing together two separate parts
to form a package by folding a blank (i.e. a sheet of packing material) about a group
of articles. By way of example, each of the glues deposited on blanks 22 and 23 may
comprise a portion of permanent, fast-dry (i.e. hot-melt) glue, and a portion of permanent,
slow-dry (i.e. cold) glue. Alternatively, in each of the glues deposited on blanks
22 and 23, a portion of non-dry, re-stick glue, analogous to non-dry, re-stick glue
79 described, may be substituted for the portion of permanent, fast-dry (i.e. hot-melt)
glue.
[0032] In the packing method described, both glues 78 and 79 are applied using gumming device
77 located upstream from packing conveyor 69, i.e. in an area in which outer blank
23 is still substantially flat, and connecting tab 20 (i.e. panel 20"' of connecting
tab 20) can be reached and gummed easily. Both glues 78 and 79 can therefore be deposited
easily and effectively on connecting tab 20 (i.e. on panel 20"' of connecting tab
20), and using a gumming device 77 that is easy to produce and assemble on packing
machine 30. This is made possible by the 'fast-setting' glue 79 being non-dry, re-stick
glue, as opposed to conventional permanent, fast-dry, hot-melt glue (which must therefore
be deposited just prior to use). Non-dry, re-stick glue 79 also provides for immediate
grip, and can be applied anywhere and at any time. In fact, being non-dry, it could,
theoretically, be deposited on outer blank 23 even days before outer blank 23 is folded.
1. A packing method for producing a package (1) by folding at least one blank (23) around
a group (2) of articles; the packing method comprising the steps of:
applying, between two parts (20"', 8) to be joined of the package (1), both a first
glue (79), and a permanent drying second glue (78) different from the first glue (79);
and
bringing the two parts (20"', 8) into contact, to glue the two parts (20"', 8) together
by means of the first glue (79) and the second glue (78);
the packing method being characterized in that the first glue (79) is non-dry, re-stick glue.
2. A packing method according to Claim 1, wherein the permanent drying second glue (78)
is a cold, preferably vinyl-based glue.
3. A packing method according to Claim 1 or 2, and comprising the further step of applying
the first and second glue (79, 78) simultaneously.
4. A packing method according to Claim 1, 2 or 3, wherein:
the package (1) is a slide-open package (1) of smoking articles, with a hinged lid
(11), and comprises:
an inner container (3) housing a group (2) of smoking articles and having an open
top end (6);
an outer container (4) housing the inner container (3) to allow the inner container
(3) to slide with respect to the outer container (4) between a closed position, in
which the inner container (3) is inserted inside the outer container (4), and an open
position, in which the inner container (3) is expelled from the outer container (4);
and
a lid (11), which is hinged to a rear wall (15) of the outer container (4), closes
the open top end (6) of the inner container (3) when closed, and is connected mechanically
to the inner container (3) by a connecting tab (20);
the inner container (3) being formed by folding a first or inner blank (22), and the
outer container (4) being formed by folding a second or outer blank (23);
the packing method comprising the further steps of:
placing the connecting tab (20) in contact with a first panel (15') of the outer blank
(23);
applying the first and second glue (79, 78) between the connecting tab (20) and a
rear wall (8) of the inner container (3); and
placing the inner container (3) on the first panel (15') of the outer blank (23),
to glue the connecting tab (20) to the rear wall (8) of the inner container (3).
5. A packing method according to Claim 4, and comprising the further steps of:
applying the non-dry, re-stick first glue (79) far away from a hinge (12') of the
connecting tab (20); and
applying the permanent drying second glue (78) close to the hinge (12') of the connecting
tab (20).