U.S. patent application number 11/527860 was filed with the patent office on 2007-06-14 for method and device for producing a cigarette packet.
This patent application is currently assigned to G.D. SOCIETA' PER AZIONI. Invention is credited to Marco Brizzi, Stefano Bruni, Luca Cerati, Paolo Degliesposti, Luca Giordano, Fabrizio Ronzani.
Application Number | 20070131233 11/527860 |
Document ID | / |
Family ID | 37606975 |
Filed Date | 2007-06-14 |
United States Patent
Application |
20070131233 |
Kind Code |
A1 |
Degliesposti; Paolo ; et
al. |
June 14, 2007 |
Method and device for producing a cigarette packet
Abstract
A method and device for producing a cigarette packet having an
inner wrapping, which is defined by a sheet of heat-seal material
folded about a group of cigarettes, and has an opening closed by an
adhesive patch; the correct position of the patch is determined
after the patch is applied to the sheet of heat-seal material.
Inventors: |
Degliesposti; Paolo;
(Bologna, IT) ; Ronzani; Fabrizio; (Bologna,
IT) ; Bruni; Stefano; (San Giovanni In Persiceto,
IT) ; Giordano; Luca; (Argelato, IT) ; Cerati;
Luca; (Bologna, IT) ; Brizzi; Marco; (Zola
Predosa, IT) |
Correspondence
Address: |
MARSHALL, GERSTEIN & BORUN LLP
233 S. WACKER DRIVE, SUITE 6300
SEARS TOWER
CHICAGO
IL
60606
US
|
Assignee: |
G.D. SOCIETA' PER AZIONI
Bologna
IT
|
Family ID: |
37606975 |
Appl. No.: |
11/527860 |
Filed: |
September 27, 2006 |
Current U.S.
Class: |
131/282 ;
53/461 |
Current CPC
Class: |
B65B 61/02 20130101;
B65B 19/228 20130101; B65D 75/5838 20130101; B65B 61/184 20130101;
B65B 19/28 20130101; B65B 57/04 20130101 |
Class at
Publication: |
131/282 ;
053/461 |
International
Class: |
A24C 5/33 20060101
A24C005/33 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 28, 2005 |
IT |
BO2005A000586 |
Claims
1) A method of producing a cigarette packet comprising an inner
wrapping (3), in turn comprising a sheet (3') of heat-seal material
folded about a group (G) of cigarettes to form a wrapped group (4)
of cigarettes; and an outer container (5), preferably of thin
cardboard, folded about the wrapped group (4) of cigarettes; the
method comprising: a feed step to feed a strip (9) of heat-seal
material along a feed path (P); a step of forming a slit (6) in the
strip (9); a first application step to apply an adhesive patch (7)
onto the slit (6); a cutting step to cut said sheet (3'), complete
with the slit (6) and the patch (7), off the strip (9); a folding
step to fold the sheet (3') about the group (G) of cigarettes to
form the wrapped group (4) of cigarettes; a sealing step to seal
superimposed portions (T) of the sheet (3') folded about the group
(G) of cigarettes; an insertion step to insert the wrapped group
(4) of cigarettes inside the outer container (5); the method being
characterized by comprising a control step to determine correct
positioning of the applied patch (7); the control step preceding
the folding step.
2) A method as claimed in claim 1, wherein the control step
precedes the cutting step.
3) A method as claimed in claim 1, wherein the control step
comprises illuminating an area about the slit (6) with diffused
light.
4) A method as claimed in claim 1, wherein the control step
comprises comparing the position of a first edge (33) of the patch
(7), substantially parallel to the feed path (P), with the position
of an edge (32) of the strip (9).
5) A method as claimed in claim 4, wherein the position of the
first edge (33) is determined in at least two separate areas (L1,
L2) of the first edge (33).
6) A method as claimed in claim 1, wherein the control step
comprises comparing the position of a second edge (34) of the patch
(7), crosswise to the feed path (P), with an element (31) printed
on the strip (9).
7) A method as claimed in claim 1, wherein, at the feed step, the
strip (9) is fed along the feed path (P) by a conveyor (8)
comprising a suction belt (35); the first application step being
performed at a first application station (12), through which the
suction belt (35) travels.
8) A method as claimed in claim 1, and comprising a reject step to
reject the sheet (3') in the event the patch (7) is found to be
positioned incorrectly at the control step.
9) A method as claimed in claim 8, wherein the reject step precedes
the folding step.
10) A method as claimed in claim 8, wherein the reject step
precedes the sealing step.
11) A method as claimed in claim 1, and comprising a detecting
step, after the first application step, to determine the presence
of the patch (7) on the strip (9); and a second application step to
apply a patch (7) on the slit (6) in the event no patch (7) is
detected on the slit (6) at the detecting step; the second
application step preceding the cutting step and following the
detecting step.
12) A method as claimed in claim 11, wherein, at the feed step, the
strip (9) is fed along the feed path (P) by a conveyor (8)
comprising a suction belt (35); the first and second application
step being performed respectively at a first and second application
station (12, 13) located along the feed path (P) at the suction
belt (35).
13) A method as claimed in claim 1, wherein at least one further
strip (39), removably supporting at least one patch (7), is fed to
the feed path (P) in a direction substantially crosswise to the
feed path (P).
14) A method as claimed in claim 1, wherein said superimposed
portions (T) are sealed by electromagnetic induction produced by an
oscillating electromagnetic field produced by a substantially fixed
generator (47); at the sealing step, movable members (48) of
nonconducting material being brought into contact with the
superimposed portions (T) to keep the superimposed portions (T)
correctly superimposed; and the sheet (3') being made of at least
partly conducting material.
15) A method as claimed in claim 1, wherein the patch (7) is
applied to the strip (9) by at least one air jet crosswise to the
feed path (P) and to a surface (25) of the strip (9).
16) A method as claimed in claim 15, wherein the patch (7) is
maintained parallel to the strip (9) by suction immediately prior
to being applied to the strip (9).
17) A method as claimed in claim 16, wherein the patch is held over
the strip (9) by suction, and the air jet blows the patch (7)
downwards onto the slit (6); the air jet being substantially
vertical.
18) A method of producing a cigarette packet comprising an inner
wrapping (3), in turn comprising a sheet (3') of heat-seal material
folded about a group (G) of cigarettes to form a wrapped group (4)
of cigarettes; and an outer container (5), preferably of thin
cardboard, folded about the wrapped group of cigarettes; the method
comprising: a feed step to feed a strip (9) of heat-seal material
along a feed path (P); a step of forming a slit (6) in the strip
(9); a first application step to apply an adhesive patch (7) onto
the slit (6); a cutting step to cut the sheet (3'), complete with
the slit (6) and the patch (7), off the strip (9); a folding step
to fold the sheet (3') about the group (G) of cigarettes to form
the wrapped group (4) of cigarettes; a sealing step to seal
superimposed portions (T) of the sheet (3') folded about the group
(G) of cigarettes; an insertion step to insert the wrapped group
(4) of cigarettes inside the outer container (5); the method being
characterized by comprising a detecting step, after the first
application step, to determine the presence of the patch (7) on the
slit (6); and a second application step to apply a patch (7) on the
slit (6) in the event no patch (7) is detected on the slit (6) at
the detecting step; the second application step preceding the
cutting step and following the detecting step.
19) A method of producing a cigarette packet comprising an inner
wrapping (3), in turn comprising a sheet (3') of heat-seal material
folded about a group (G) of cigarettes; the method comprising: a
feed step to feed a strip (9) of heat-seal material along a feed
path (P); a step of forming a slit (6) in the strip (9); an
application step to apply an adhesive patch (7) onto the slit (6);
a cutting step to cut said sheet (3'), complete with the slit (6)
and the patch (7), off the strip (9); a folding step to fold the
sheet about the group (G) of cigarettes to form a wrapped group (4)
of cigarettes; a sealing step to seal superimposed portions (T) of
the sheet folded about the group (G) of cigarettes; the method
being characterized in that, at the feed step, the strip is fed
along the feed path (P) by a conveyor (8) comprising a suction belt
(35); the application step being performed at an application
station (12) located along the feed path (P) at the suction belt
(35).
20) A method of producing a cigarette packet comprising a wrapping
(3) of heat-seal material; the method comprising: a folding step to
fold a sheet (3') of at least partly conductive heat-seal material
about an article, in particular a group (G) of cigarettes; a
sealing step to seal superimposed portions (T) of the sheet (3')
folded about the group (G) of cigarettes; the method being
characterized in that said superimposed portions (T) are sealed by
electromagnetic induction produced by a variable electromagnetic
field produced by a substantially fixed generator (47); at the
sealing step, movable members (48) of nonconducting material being
brought into contact with the superimposed portions (T) to keep the
superimposed portions (T) correctly superimposed.
21) A method of producing a cigarette packet comprising an inner
wrapping (3), in turn comprising a sheet (3') of heat-seal material
folded about a group (G) of cigarettes; the method comprising: a
feed step to feed a strip (9) of heat-seal material along a feed
path (P); a step of forming a slit (6) in the strip (9); an
application step to apply an adhesive patch (7) onto the slit (6);
a cutting step to cut said sheet, complete with the slit (6) and
the adhesive patch (7), off the strip (9); a folding step to fold
the sheet (3') about the group (G) of cigarettes to form a wrapped
group (4) of cigarettes; a sealing step to seal superimposed
portions (T) of the sheet (3') folded about the group (G) of
cigarettes; the method being characterized in that the patch (7) is
applied to the strip (9) by at least one air jet crosswise to the
feed path (P) and to a surface (25) of the strip (9).
22) A device for producing a cigarette packet comprising an inner
wrapping, in turn comprising a sheet of heat-seal material folded
about a group (G) of cigarettes to form a wrapped group (4) of
cigarettes; and an outer container (5), preferably of thin
cardboard, folded about the wrapped group (4) of cigarettes; the
device (1) comprising: a conveyor (8) for feeding a strip (9) of
heat-seal material along a feed path (P) through a slitting station
(11) and a first application station (12) to a cutting station
(10); an operating unit (15) located at the slitting station (11)
to form a slit (6) in the strip (9); a first application unit (16)
located at the first application station (12) to apply an adhesive
patch (7) onto the slit (6); a cutting assembly (42) located at the
cutting station (10) to cut said sheet (3'), complete with the slit
(6) and the patch (7), off the strip (9); a folding assembly (43)
for folding the sheet about the group (G) of cigarettes to form the
wrapped group (4) of cigarettes; a sealing assembly (44) for
sealing superimposed portions (T) of the sheet (3') folded about
the group (G) of cigarettes; and a packing assembly (50) for
inserting the wrapped group (4) of cigarettes inside the outer
container (5); the device (1) being characterized by comprising a
control unit (23) for determining correct positioning of the patch
(7) on the slit (6); the control unit (23) being located upstream
from the folding assembly (43).
23) A device as claimed in claim 22, wherein the control unit (23)
is located upstream from the cutting assembly (42) along the feed
path (P).
24) A device as claimed in claim 22, wherein the control unit (23)
comprises a detector (24); and lighting means (26, 27) for
illuminating a surface (25) of the strip (9) with diffused
light.
25) A device as claimed in claim 24, wherein the lighting means
(26, 27) comprise a cover (27), a concave surface (28) of which is
positioned facing the feed path (P); and at least two light sources
(26) located on opposite sides of the feed path (P), and which
direct light onto the concave surface (28), which reflects the
light to illuminate, in use, the surface (25) of the strip (9).
26) A device as claimed in claim 25, wherein the cover (27) and the
detector (24) are located over the feed path (P).
27) A device as claimed in claim 24, wherein the detector (24)
determines the position of edges (33, 34) of the patch (7).
28) A device as claimed in claim 22, wherein the control unit (23)
determines the presence of the slit (6).
29) A device as claimed in claim 22, and comprising a lighting
device (29) and a detector (24); the lighting device (29) and the
detector being located on opposite sides of the feed path (P); and
the detector (24) detecting the light travelling through the slit
(6).
30) A device as claimed in claim 22, wherein the conveyor (8)
comprises a suction belt (35) for feeding the strip (9) through the
first application station (12).
31) A device as claimed in claim 22, and comprising a reject unit
(52) for rejecting the sheet (3') on the basis of the findings of
the control unit (23).
32) A device as claimed in claim 22, and comprising a second
application unit (17) located downstream from the first application
unit (16) along the feed path (P), and which applies the patch (7)
onto the slit (6) in the event no patch (7) is applied onto the
slit (6) by the first application unit (16).
33) A device as claimed in claim 32, and comprising a detecting
unit (18) located downstream from the first application station
(12) along the feed path (P) to detect the presence of the patch
(7) on the strip (9); the second application unit (17) being
located downstream from the detecting unit (18) along the feed path
(P), and applying a patch (7) onto the slit (6) in the event the
detecting unit (18), in use, detects no patch on the slit.
34) A device as claimed in claim 22, wherein the first application
unit (16) comprises a feed assembly (38) for feeding a further
strip (39), removably supporting at least one patch (7), to the
first application station (12) in a direction substantially
crosswise to the feed path (P).
35) A device as claimed in claim 22, wherein the sealing assembly
(44) comprises at least one oscillating electromagnetic field
generator (47); at least one movable member (48) of nonconducting
material; and actuating means (49) which move the movable member
(48) into contact with said superimposed portions (T) to keep the
superimposed portions (T) correctly superimposed; the generator
(47) being substantially fixed.
36) A device as claimed in claim 22, wherein the first application
unit (16) comprises blow means for blowing the patch (7) onto the
strip (9) by emitting at least one air jet crosswise to the feed
path (P) and to a surface (25) of the strip (9).
37) A device as claimed in claim 36, wherein the first application
unit (16) comprises suction means for maintaining the patch (7)
parallel to the strip (9) at the first application station
(12).
38) A device as claimed in claim 36, wherein the air jet is
substantially vertical.
39) A device for producing a cigarette packet comprising an inner
wrapping (3), in turn comprising a sheet (3') of heat-seal material
folded about a group (G) of cigarettes to form a wrapped group (4)
of cigarettes; and an outer container (5), preferably of thin
cardboard, folded about the wrapped group (4) of cigarettes; the
device (1) comprising: a conveyor (8) for feeding a strip (9) of
heat-seal material along a feed path (P) through a slitting station
(11) and a first application station (12) to a cutting station
(10); an operating unit (15) located at the slitting station (11)
to form a slit (6) in the strip (9); a first application unit (16)
located at the first application station (12) to apply an adhesive
patch (7) onto the slit (6); a cutting assembly (42) located at the
cutting station (10) to cut said sheet (3'), complete with the slit
(6) and the patch (7), off the strip (9); a folding assembly (43)
for folding the sheet (3') about the group (G) of cigarettes to
form the wrapped group (4) of cigarettes; a sealing assembly (44)
for sealing superimposed portions (T) of the sheet (3') folded
about the group (G) of cigarettes; and a packing assembly (50) for
inserting the wrapped group (4) of cigarettes inside the outer
container (5); the device (1) being characterized by comprising a
detecting unit (18) located downstream from the first application
station (12) along the feed path (P) to detect the presence of the
patch (7) on the strip (9); and a second application unit (17)
located downstream from the detecting unit (18) along the feed path
(P) to apply a patch (7) onto the slit (6) in the event the
detecting unit (18), in use, detects no patch (7) on the slit
(6).
40) A device for producing a cigarette packet comprising an inner
wrapping (3), in turn comprising a sheet (3') of heat-seal material
folded about a group (G) of cigarettes; the device (1) comprising:
a conveyor (8) for feeding a strip (9) of heat-seal material along
a feed path (P) through a slitting station (11) and an application
station (12; 13) to a cutting station (10); an operating unit (15)
located at the slitting station (11) to form a slit (6) in the
strip (9); an application unit (16; 17) located at the application
station (12; 13) to apply an adhesive patch (7) onto the slit (6);
a cutting assembly (42) located at the cutting station (10) to cut
said sheet (3'), complete with the slit (6) and the patch (7), off
the strip (9); a folding assembly (43) for folding the sheet (3')
about the group (G) of cigarettes to form a wrapped group (4) of
cigarettes; and a sealing assembly (44) for sealing superimposed
portions (T) of the sheet (3') folded about the group (G) of
cigarettes; the device (1) being characterized in that the conveyor
(8) comprises a suction belt (35) for feeding the strip (9) through
the application station (12; 13).
41) A device for producing a cigarette packet comprising an inner
wrapping (3), in turn comprising a sheet (3') of heat-seal
material; the device (1) comprising: a folding assembly (43) for
folding the sheet (3') about a group (G) of cigarettes to form the
wrapped group (4) of cigarettes; and a sealing assembly (44) for
sealing superimposed portions (T) of the sheet (3') folded about
the group (G) of cigarettes; the device (1) being characterized in
that the sealing assembly (44) comprises at least one oscillating
electromagnetic field generator (47); at least one movable member
(48) of nonconducting material; and actuating means (49) which move
the movable member (48) into contact with said superimposed
portions (T) to keep the superimposed portions (T) correctly
superimposed; the generator (47) being substantially fixed.
42) A device for producing a cigarette packet (2) comprising an
inner wrapping (3), in turn comprising a sheet (3') of heat-seal
material folded about a group (G) of cigarettes; the device (1)
comprising: a conveyor (8) for feeding a strip (9) of heat-seal
material along a feed path (P) through a slitting station (11) and
an application station (12; 13) to a cutting station (10); an
operating unit (15) located at the slitting station (11) to form a
slit (6) in the strip (9); an application unit (16; 17) located at
the application station (12; 13) to apply an adhesive patch (7)
onto the slit (6); a cutting assembly (42) located at the cutting
station (10) to cut said sheet (3'), complete with the slit (6) and
the patch (7), off the strip (9); a folding assembly (43) for
folding the sheet (3') about the group (G) of cigarettes to form a
wrapped group (4) of cigarettes; and a sealing assembly (44) for
sealing superimposed portions (T) of the sheet (3') folded about
the group (G) of cigarettes; the device (1) being characterized in
that the application unit (16; 17) comprises blow means for blowing
the patch (7) onto the strip (9) by emitting at least one air jet
crosswise to the feed path (P) and to a surface (25) of the strip
(9).
Description
[0001] The present invention relates to a method and device for
producing a cigarette packet.
[0002] More specifically, the present invention relates to a device
for producing a cigarette packet comprising an inner wrapping, in
turn comprising a sheet of heat-seal material folded about a group
of cigarettes to form a wrapped group of cigarettes; and an outer
container, preferably made of thin cardboard, folded about the
wrapped group of cigarettes. The device comprises a conveyor for
feeding a strip of heat-seal material to a cutting station. The
device also comprises an operating unit located at a slitting
station to form a slit in the strip; an application unit located at
a application station to apply a patch; a cutting assembly located
at the cutting station to cut the sheet, complete with the slit,
off the strip; a folding assembly for folding the sheet about the
group of cigarettes to form the wrapped group of cigarettes; a
sealing assembly for sealing superimposed portions of the sheet
folded about the group of cigarettes; and a packing assembly for
inserting the wrapped group of cigarettes inside the outer
container.
BACKGROUND OF THE INVENTION
[0003] One example of a packet produced using devices of the above
type is described in Patent Application WO98/22367.
[0004] Known devices of the above type have several drawbacks,
including: relatively slow production of the sheet complete with
the patch; and production of poor-quality packets, due to incorrect
location or absence of the patch and/or slit on the sheet.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide a device
and method designed to at least partly eliminate the aforementioned
drawbacks, and which at the same time are cheap and easy to
implement.
[0006] According to the present invention, there are provided a
method and device as claimed in the attached Claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] A non-limiting embodiment of the present invention will be
described by way of example with reference to the accompanying
drawings, in which:
[0008] FIG. 1 shows a schematic partial front view of a device in
accordance with the present invention;
[0009] FIG. 2 shows a schematic of part of the FIG. 1 device;
[0010] FIG. 3 shows a side view of a detail of the FIG. 2 part;
[0011] FIG. 4 shows an underside view of part of the FIG. 3
detail;
[0012] FIGS. 5 and 6 show a further detail of the FIG. 1 device in
two successive positions;
[0013] FIG. 7 shows a view in perspective of a further detail of
the FIG. 1 device;
[0014] FIG. 8 shows a packet produced using the FIG. 1 device;
[0015] FIG. 9 shows a sheet by which to produce the FIG. 8
packet;
[0016] FIG. 10 shows a topside view of a further detail of the FIG.
2 part.
DETAILED DESCRIPTION OF THE INVENTION
[0017] Number 1 in FIG. 1 indicates as a whole a device for
producing a cigarette packet 2 (FIG. 8) comprising an inner
wrapping 3, in turn comprising a sheet 3' (FIG. 9) of heat-seal
material folded about a group G of cigarettes to define a wrapped
group 4 of cigarettes; and an outer container 5, preferably made of
thin cardboard, folded about wrapped group 4 of cigarettes.
[0018] More specifically, sheet 3' is made of multilayer laminated
material, in which one or more layers comprise metal material, and
other layers comprise plastic material. Sheet 3' (FIG. 9) has a
substantially U-shaped slit 6 defining an opening in wrapping 3;
and a patch 7 having an adhesive face and applied over slit 6 to
close inner wrapping 3
[0019] Packet 2 is substantially identical to the packet described
in WO98/22367, which is included herein by way of reference.
[0020] Device 1 comprises a conveyor 8 (FIG. 2) for feeding a strip
9 of heat-seal material to a cutting station 10 (FIG. 1) along a
feed path P and via a slitting station 11, two application stations
12 and 13 (FIG. 2) and a control station 14 (FIG. 7). Application
station 13 is located downstream from application station 12, which
in turn is located downstream from slitting station 11; and control
station 14 is located downstream from application station 13.
[0021] Device 1 (FIG. 2) also comprises an operating unit 15
located at slitting station 11 to form slit 6 in strip 9; an
application unit 16 located at application station 12 to apply
patch 7 onto slit 6; an application unit 17 located at application
station 13; and a detecting unit 18 located between application
stations 12 and 13 to determine the presence of patch 7 on strip
9.
[0022] In actual use, strip 9 is cut at cutting station 10 to
detach sheet 3', complete with patch 7 and slit 6, from strip
9.
[0023] Device 1 also comprises a central control unit 19 connected
to a sensor 20 of detecting unit 18 to activate application unit 17
when sensor 20 detects no patch 7 on slit 6.
[0024] Providing application unit 17 downstream from application
unit 16 enables high-speed operation of device 1. In this
connection, it is important to note that applying patch 7 to strip
9 is a relatively slow job, and only one application unit 16 or 17
would not guarantee correct application of patches 7 to successive
slits 6 when strip 9 is fed through at high speed. Moreover,
providing application unit 17 downstream from application unit 16
allows the operator to stop either one of the application units
temporarily for maintenance purposes (cleaning the application
unit, changing the reel of strip 39 removably supporting patch 7)
without interrupting production of cigarette packets 2.
[0025] Operating unit 15 comprises a roller 21 rotating about a
respective axis 22 and having a known peripheral blade (not shown)
which rotates about axis 22 and into contact with strip 9 to form
slit 6.
[0026] With reference to FIG. 7, control station 14 has a control
unit 23 for determining correct placement of patch 7 on slit 6.
[0027] Control unit 23 comprises a detector 24; and a lighting
system for illuminating a top surface 25 of strip 9 with diffused
light, and which in turn comprises two light sources 26 located on
opposite sides of path P and alongside strip 9, and a cover 27
(shown by a dash line in FIG. 7). Cover 27 is positioned over path
P, and has a downwardly-concave surface 28 facing path P and
surface 25. Light sources 26 direct inclined light onto concave
surface 28, which reflects it to illuminate surface 25.
[0028] Detector 24 is located over path P and housed in a seat in
cover 27.
[0029] It is important to note that, using diffused light, detector
24 is able to detect the edges of patch 7, even when patch 7 is
substantially the same colour as strip 9.
[0030] Control unit 23 also comprises a lighting device 29
underneath path P to direct light onto slit 6; and the light
through slit 6 is detected by detector 24 to determine the presence
of slit 6 on the strip. A supporting surface S, on which strip 9
runs at control station 14, has a slot F through which the light
from lighting device 29 passes. Detector 24, lighting device 29,
and slot F are preferably aligned vertically.
[0031] Cover 27 is movable to allow the operator free access to
control unit 23.
[0032] Control unit 23 also comprises a sensor 30 for detecting a
reference element 31 printed on strip 9.
[0033] Operation of control unit 23 will now be described as of the
instant in which element 31 is detected by sensor 30. Light sources
26 emit a flash of light, and an image is acquired by detector 24
and processed by central control unit 19, to which detector 24 is
connected (the connection between detector 24 and central control
unit 19 is not shown). Central control unit 19 compares detected
values with reference values, and, in the event the detected values
are incompatible with the reference values, emits an error signal.
More specifically, central control unit 19 compares the position of
an edge 32 of strip 9 with the position--determined in two areas L1
and L2--of a longitudinal edge 33 of patch 7, and compares the
position of a transverse edge 34 of patch 7 with the position
(detected by sensor 30) of element 31.
[0034] In this way, control unit 23 is able to determine accurately
whether patch 7 is correctly oriented and positioned longitudinally
and transversely with respect to strip 9.
[0035] The absence of slit 6 is indicated when detector 24 fails to
receive sufficient light through slot F.
[0036] Conveyor 8 (FIG. 2) comprises a suction belt 35 for feeding
strip 9 through application stations 12 and 13, and beneath which
is located a suction device 36 (shown by the dash line in FIG. 2).
Suction belt 35 prevents strip 9 from moving crosswise to path P,
and, at the same time, ensures slit 6, formed beforehand in strip
9, is held down as application unit 16 or 17 deposits patch 7 on
strip 9, thus ensuring extremely precise application of patch 7 on
strip 9.
[0037] The precision with which patch 7 is applied to strip 9 is
further improved by the particular structure and operation of
application units 16 and 17.
[0038] Application unit 16 (FIG. 3) comprises an applicator head
37; and a conveyor 38 for feeding a strip 39, removably supporting
patch 7, to applicator head 37 in a direction crosswise to path
P.
[0039] In actual use, strip 39 is fed about a blade 40 to detach
patch 7 from strip 39. Applicator head 37 has a known suction
system (not shown) for holding patch 7 on a perforated bottom
surface 41 of applicator head 37; which surface 41 (FIG. 4) is
located over path P, is substantially horizontal, and is
substantially parallel to surface 25.
[0040] Applicator head 37 also emits air jets through surface 41
and in a direction crosswise to path P. More specifically, the air
jets are directed downwards in a direction substantially
perpendicular to path P and surface 25, so that patch 7 is detached
downwards from surface 41 and moves parallel to itself in a
substantially vertical direction.
[0041] Application unit 17 is substantially identical to
application unit 16.
[0042] At cutting station 10, a known cutting assembly 42 (shown
schematically in FIG. 1) cuts strip 9 to separate sheet 3',
complete with patch 7 and slit 6, from strip 9.
[0043] Device 1 also comprises a known folding assembly 43 (shown
schematically in FIG. 1) which folds sheet 3' about group G of
cigarettes to form wrapped group 4; and a sealing assembly 44 for
sealing superimposed portions T of sheet 3' folded about group G of
cigarettes.
[0044] Sealing assembly 44 comprises a wheel 45 (shown by a
continuous line in FIG. 1 and by a dash line in FIGS. 5 and 6), in
turn comprising a number of known peripheral seats (not shown),
each for housing a respective wrapped group 4.
[0045] With particular reference to FIGS. 5 and 6, sealing assembly
44 also comprises two sealing units 46 on opposite sides of wheel
45. Each sealing unit 46 comprises an oscillating magnetic field
generator 47 (shown schematically); a movable member 48 of
nonconducting material; and an actuator 49 for moving movable
member 48 into contact with said portions T of sheet 3' to keep
portions T superimposed correctly. Generator 47 is maintained in a
substantially fixed position.
[0046] The oscillating magnetic fields generated by generator 47
induce heat in certain areas of sheet 3', by virtue of sheet 3'
containing metal components.
[0047] In this way, good-quality seals can be achieved, while at
the same time reducing the risk of damage to sheet 3' and/or the
cigarettes (not shown) wrapped in sheet 3'.
[0048] This is achieved in an extremely straightforward, low-cost
manner by not moving generators 47.
[0049] Generators 47 are preferably oil-cooled.
[0050] Though the FIG. 5 and 6 embodiment shows two actuators 49,
one for each sealing unit 46, it should be pointed out that,
alternatively, movable members 48 may be operated by a single
mechanical mechanism.
[0051] An embodiment not shown of sealing assembly 44 comprises a
conventional sealing unit, with a heating element, instead of
electromagnetic-induction sealing unit 46.
[0052] Device 1 also comprises a packing assembly 50 for inserting
wrapped group 4 inside outer container 5.
[0053] More specifically, wrapped group 4 may be inserted inside a
preformed outer container 5, or outer container 5 may be formed
about wrapped group 4. Herein, the expression "insert the wrapped
group of cigarettes inside the outer container" includes both the
above alternatives.
[0054] In preferred embodiments not shown, a suction compensation
chamber for strip 9 is provided between application station 13 and
control station 14, and is, for example, of the type described in
EP 949174, which is included herein by way of reference.
[0055] In other preferred embodiments not shown, a number of
sensors, each for detecting the presence of element 31, are located
along path P; in which case, central control unit 19 regulates
operation of the assemblies and units of device 1 as a function of
the findings of the sensor.
[0056] Operation of device 1 will now be described as a whole, as
of the instant in which operating unit 15 forms slit 6. At this
point, strip 9 is fed continuously along path P through application
stations 12 and 13, where patch 7 is applied to slit 6, and through
control station 14 to cutting station 10. Sheet 3' is formed at
cutting station 10 and fed through a reject station 51, where a
reject unit 52 eliminates any flawed sheets 3'.
[0057] If not rejected, sheet 3' is fed to folding assembly 43,
which folds sheet 3' about group G of cigarettes to form wrapped
group 4. Inner wrapping 3 is then stabilized by sealing assembly
44. And, finally, the wrapped group 4 is inserted inside outer
container 5.
[0058] In alternative embodiments not shown, reject station 51 is
located downstream from sealing assembly 44.
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