IT202100030185A1 - Unit and cutting method for removing a strip from a package wall - Google Patents

Description

DESCRIPTION

of the industrial invention entitled:

"Unit and cutting method for removing a strip from a package wall"

TECHNICAL SECTOR

This invention? relating to a unit? and a cutting method for removing a strip from a wall of a package particularly of smoking articles.

The present invention finds advantageous application in a packaging machine (for example a cellophane wrapping machine) for the production of a so-called "book-pack" packet of cigarettes, which the following discussion will cover. explicit reference without losing generality.

PRIOR ART

A pack of cigarettes ?book-pack? includes (at least) two containers, which house respective groups of wrapped cigarettes, have respective ends? open tops, and are hinged to each other to be able to rotate between a closed configuration, in which the two containers are superimposed on each other, and an open configuration, in which the two containers are separated; Furthermore, ? provided a lid that is hinged to a rear container and, when in a closed position, hugs the top of both containers.

The production of a cigarette pack ?book-pack? involves forming the two containers using two corresponding blanks which are folded around the respective groups of wrapped cigarettes, coupling (overlapping) the two containers, and then folding a third blank which joins the two containers around the two coupled (overlapping) containers and creates the common lid.

After bending the third blank? necessary to make a cut on the bottom wall of the ?book-pack? to allow the separation of the two containers (i.e. to allow the two containers to rotate relative to each other); normally a double cut is made (i.e. two cuts close together and parallel to each other) to remove a strip (strip) from the back wall in such a way as to create a clear separation between the two containers. Is a unit used for this purpose? what cut? equipped with two parallel and adjacent rotating blades which are partially housed in a collection chamber in which a suction acts which should capture and remove the strip as soon as the strip itself is removed. been separated from the rest of the back wall. However, isn't it? it is rare that even after the cut made by the two rotating blades the strip remains stuck in the back wall and therefore is not removed by the suction; consequently, downstream of the unit? cutting some packets of cigarettes ?book-pack? still have the strip on the bottom that can? be more? or less in the original position. Can this? generate various problems such as the loss of the strip in the machine before applying the transparent plastic overwrapping or the wrapping (with the transparent plastic overwrapping) of the strip together with the package in completely random positions, providing the end user with the impression of a package of poor quality cigarettes.

DESCRIPTION OF THE INVENTION

Purpose of the present invention? provide a unit? and a cutting method for removing a strip from a wall of a package in particular of smoking articles which allows to ensure the removal of the strip after cutting and, at the same time, is easy and economical to produce.

In accordance with the present invention, a unit is supplied and a cutting method for removing a strip from a wall of a package in particular of smoking articles, as claimed in the attached claims.

The claims describe embodiments of the present invention forming an integral part of the present description.

BRIEF DESCRIPTION OF THE DRAWINGS

Will this invention come? now described with reference to the attached drawings, which illustrate a non-limiting example of implementation, in which:

? figure 1? a perspective view of a pack of cigarettes ?book-pack? in a closed configuration;

? figure 2? a perspective view of the cigarette pack of FIG. 1 in an open configuration;

? figure 3? a view of a blank used to make the cigarette pack of FIG. 1;

? figure 4? a perspective view of a unit? cutting tool to remove a strip from a bottom wall of the cigarette pack of figure 1;

? figure 5? a further perspective view of the unit? cutting edge of figure 4;

? figure 6? a perspective view of a cutting group of the unit? cutting edge of figure 4;

? figure 7? a perspective view of a pneumatic distributor of the cutting unit of figure 6;

? figure 8? a perspective and exploded view of the rotating blades of the cutting unit of figure 6;

? figure 9? a longitudinal section view of the rotating blades of the cutting unit of figure 6; And

? figure 10? a perspective view from below of the cigarette pack of figure 1 in the closed configuration and with evidence of a strip being removed from the back wall.

PREFERRED FORMS OF IMPLEMENTATION OF THE INVENTION

In figures 1 and 2, with the number 1 ? indicated as a whole a pack of cigarettes ?book-pack? comprising two containers 2 and 3, which house respective groups of wrapped cigarettes, have respective ends? upper ones open, and are hinged to each other to be able to rotate between a closed configuration (illustrated in figure 1), in which the two containers 2 and 3 are superimposed on each other, and an open configuration (illustrated in figure 2), in which the two containers 2 and 3 are separate; Furthermore, ? there is a lid 4 which is hinged to a rear container 2 and, when in a closed position, embraces the top of both containers 2 and 3.

According to a preferred embodiment illustrated in the attached figures, the rear container 2 is more? large and accommodates a group of cigarettes wrapped more? large (for example composed of two layers of seven cigarettes each), while the front container 3 is more? small and accommodates a smaller wrapped pack of cigarettes? small (for example composed of a single layer of six cigarettes); according to a different embodiment not illustrated, the two containers 2 and 3 have the same size.

The production of the cigarette pack 1 involves forming the two containers 2 and 3 using two corresponding blanks (not shown) which are folded around the respective wrapped groups of cigarettes, coupling (overlapping) the two containers 2 and 3, and then fold a third blank 5 (shown in figure 3) around the two coupled (overlapping) containers 2 and 3, which joins the two containers 2 and 3 and creates the common lid 4.

The cigarette pack 1 includes a bottom wall 6 (illustrated for example in figure 3) which is located on the outside, ? part of the blank 5, and embraces both containers 2 and 3; that is, the bottom walls of the two containers 2 and 3 are placed against the bottom wall 6 which covers them.

After bending the blank 5 ? it is necessary to make a cut 7 (schematically illustrated in figure 3) on the bottom wall 6 of the cigarette pack 1 to allow the separation of the two containers 2 and 3 (i.e. to allow the two containers 2 and 3 to rotate with respect to each other) . In other words, initially the back wall 6? completely intact and therefore devoid of any division and consequently does not allow any movement between the two containers 2 and 3; ? it is therefore necessary to make the cut 7 to divide the bottom wall 6 into two parts which can be moved away from each other to allow movement between the two containers 2 and 3.

In figure 4, with the number 8 ? indicated as a whole a unit? of cutting which, to create a clear separation between the two containers 2 and 3, performs the cutting 7 of a packet 1 of cigarettes which is advanced along a straight path P by a conveyor 9; cut 7? double (that is, it is made up of two cuts close together and parallel to each other) to remove a strip B or strip (illustrated in figure 10) from the back wall 6, you have a width of approximately 1 mm; or the unit? Cutting figure 8 removes a relatively thin central part (the strip B) from the bottom wall 6 of a packet 1 of cigarettes to divide the two containers 2 and 3.

As illustrated in figure 9, the unit? 8 cutting includes two coaxial and horizontally arranged rotating blades 10 which are mounted to rotate around the same vertical rotation axis 11 at a certain distance from each other and create on the wall 6 a packet 1 of cigarettes which advances along the path P a double cut 7 which separates the strip B from the rest of the wall 6 of the packet 1 of cigarettes. That is, the two rotating blades 10 of circular shape are parallel and adjacent to each other and are mounted to rotate around the same vertical rotation axis 11 (i.e. the two rotating blades 10 are identical to each other and coaxial); in use the two rotating blades 10 make two parallel cuts on the bottom wall 6 of a pack 1 of cigarettes which advances along the path P which separate the strip B from the rest of the bottom wall 6 of the pack 1 of cigarettes. According to a further embodiment not illustrated, the two rotating blades 10 could have a predominantly vertical orientation rather than predominantly horizontal as illustrated in the attached figures. Furthermore, the two rotating blades 10 may not be perfectly identical to each other (twins) and therefore present differences with respect to each other. Finally, the two cuts that separate the strip B from the rest of the bottom wall 6 and are made by the two rotating blades 10 may not be perfectly parallel to each other (i.e. they could be slightly convergent or divergent with respect to each other).

As illustrated in figure 5, the unit? 8 cutting includes an actuator device 12 which includes an electric motor and carries out the rotation of the two blades 10 rotating around the rotation axis 11; the two rotating blades 10 rotate for example at one speed? rotation of approximately 1500 rpm which always remains constant.

As illustrated in figure 5, the unit? 8 cutting includes a suction duct 13 (i.e. connected to a suction source) designed to suck the strip B which is had just been cut by the two rotating 10 blades; or the function of the suction duct 13? to convey by suction the band B which is? been separated from the back wall 6 by the double cut 7 so as to bring the strip B into a specific collection area (not illustrated). By way of example, the suction in the suction duct 13 can be created using an impeller or a flow accelerator. According to a preferred embodiment, one end? initial of the suction duct 13 has a conical shape having the minimum dimension in correspondence with the rotating blades 10 (i.e. having a dimension which progressively widens moving away from the rotating blades 10) in such a way as to have the maximum depression in correspondence with the rotating blades 10.

As illustrated in figure 5, the unit? 8 includes a fixed containment guide 14 against which the bottom wall 6 of the cigarette packet 1 slides and is provided with a passing slot 15 through which the two rotating blades 10 are arranged (i.e. through which the two rotating blades 10 come into contact with the bottom wall 6 of the cigarette pack 1); for this purpose, the slot 15 passing through the guide 14 is fixed? little more? wide of the pair of rotating blades 10 to allow their insertion beyond the fixed guide 14 with minimal play.

As illustrated in figure 6, the unit? 8 includes a pneumatic device 16 configured to apply a suction between the two rotating blades 10 which acts on the strip B which is separated from the bottom wall 6 of the cigarette pack 1 by the double cut 7 performed by the two rotating blades 10 themselves. That is, the suction generated by the pneumatic device 16 tends to make the strip B adhere between the two rotating blades 10, "tearing" it. then the strip B from the bottom wall 6 of the cigarette pack 1 as the double cut 7 proceeds. In this way, the strip B does not remain stuck in the bottom wall 6 of the cigarette pack 1, but is removed from the bottom wall 6 of the cigarette pack 1 as the double cutting 7 proceeds. Furthermore, according to a preferred embodiment, the pneumatic device 16 is also configured to apply a blow between the two rotating blades 10 which acts on the strip B after the execution of the double cut 7 (i.e. once the double cut 7 has been completed) to move the strip B away from the rotating blades 10 and therefore allows to the suction duct 13 to "capture" and then definitively remove the strip B. In other words, the pneumatic device 16 is ? configured to apply alternately between the two rotating blades 10 a suction that acts on the strip B during the execution of the double cut 7 (to remove the strip B from the bottom wall 6 of the cigarette pack 1) and a breath that acts on the strip B after performing the double cut 7 (to push the strip B towards the suction duct 13).

As illustrated in figures 8 and 9, the unit? 8 cutting includes a support disk 17, which is coaxial to the two rotating blades 10, ? interposed between the two rotating blades 10 to form a single assembly with the rotating blades 10 (i.e. it is clamped together with the two rotating blades 10) and is rotatable mounted together with the two blades 10 rotating around the rotation axis 11. The support disk 17 laterally delimits a plurality? of 18 rooms, each of which ? open towards the outside and in which a suction and an overpressure is alternately applied (to generate a blast of compressed air). The chambers 18 are uniformly distributed around the rotation axis 11 and each have a substantially parallelepiped shape. Each room 18? delimited laterally by the support disk 17 and is delimited above and below by the rotating blades 10. In other words, each room 18 ? consisting of a through opening that passes through the support disk 17 from wall to side.

As illustrated in figure 8, the support disk 17 has an external edge 19 which is located between the two rotating blades 10 and is interrupted by the openings of the chambers 18 from which the suction and the breath alternately emerge; in use the strip B separated by the double cut 7 from the bottom wall 6 of the cigarette pack 1 and attracted by the suction that comes out of the openings of the chambers 18 rests on the external edge 19 of the support disk 17 and remains in contact with the edge 19 outside of the support disk 17 until a breath of compressed air comes out of the openings of the chambers 18.

As illustrated in figure 8, each chamber 18 has an end 20 internal what? connected to a pneumatic distributor 21 (illustrated in figures 6 and 7) and one end? 22 external what? radially opposite to the extremity? 20 internal and ? open through the outer edge 19 of the support disk 17; therefore in use the suction and overpressure run along each chamber 18 from the end 20 internal to the end? 22 from which they emerge from the support disk 17 by acting on the strip B separated by the double cut 7 from the bottom wall 6 of the cigarette pack 1.

As illustrated in figure 8, the two rotating blades 10 are perfectly identical to each other for simplicity's sake. construction (so as not to have to create two rotating blades 10 that are slightly different from each other and therefore to have a single type of perfectly interchangeable rotating blades 10) and therefore each rotating blade 10 has a series of through holes 23, each of which is ? axially overlapped by one end? 20 inside a corresponding chamber 18. For a single rotating blade 10, each passing hole 23 connects the end 20 inside a corresponding chamber 18 with the pneumatic distributor 21 arranged beyond? of the rotating blade 10 itself, while for the other rotating blade 10 each passing hole 23 has no function as beyond of the rotating blade 10 itself is not there?? nothing (i.e. each through hole 23 ends against a solid wall which seals the through hole 23 itself). So, for simplicity's sake? construction both rotating blades 10 have through holes 23, but only the through holes 23 of a single rotating blade 10 have the function of connecting the end? 20 inside the chambers 18 with the pneumatic distributor 21, while the through holes 23 of the other rotating blade 10 have no function.

As illustrated in figures 6 and 7, the pneumatic distributor 21 comprises a cylindrical body 24 which is immobile, i.e. it does not rotate around the rotation axis 11, and is coupled to 10 rotating blades. In other words, a top rotating 10 blade ? arranged in contact with the cylindrical body 24 and rotating around the rotation axis 11 it slides against the cylindrical body 24 which however does not rotate around the rotation axis 11. As illustrated in figure 7, the cylindrical body 24 has a compartment 25 which is shaped like a circular arc, ? coaxial to the rotation axis 11, ? permanently connectable to a suction source, and is? arranged in correspondence with the through holes 23 of the rotating blades 10 and therefore in correspondence with the ends? 20 inside the chambers 18 of the support disk 17. Furthermore, the cylindrical body 24 has a compartment 26 which is shaped like a circular arc, ? coaxial to the rotation axis 11, ? permanently connectable to a source of compressed air, and is? arranged next to the compartment 25 in correspondence with the through holes 23 of the rotating blades 10 and therefore in correspondence with the ends 20 inside the chambers 18 of the support disc 17. During the rotation of the assembly consisting of the rotating blades 10 and the support disk 17, the end The internal 20 of each chamber 18 of the support disk 17 is located for approximately 180? isolated from both rooms 25 and 26, it is located for approximately 90? in connection (through the corresponding passing hole 23) with the compartment 25 to receive a suction (while the rotating blades 10 are performing the double cut 7 which separates the strip B from the bottom wall 6 of the cigarette pack 1) and is subsequently found for about 90? in connection (through the corresponding passing hole 23) with the compartment 26 to receive an overpressure (when the rotating blades 10 have finished the double cut 7 which separates the strip B from the bottom wall 6 of the cigarette pack 1 and therefore the strip B must be pushed towards the suction duct 13).

According to a possible form of implementation, the unit? 8 cutting includes a cleaning device (i.e. a sort of scraper) which? arranged in a fixed position around the two rotating blades 10, it is located at a reduced distance from the two rotating blades 10, and has the function of cleaning the two rotating blades 10 from any foreign elements (pieces of cardboard from the bottom wall 6) that have remained stuck between the two rotating blades 10 or remained attached to a rotating blade 10. In other words, the cleaning device separates from the rotating blades 10 any foreign elements (pieces of cardboard from the bottom wall 6) that have remained stuck between the two rotating blades 10 or have remained attached to a rotating blade 10.

According to a possible form of implementation, ? A control station is also foreseen which could be placed along the route P downstream of the unit. 8 cutting and ? equipped with a vision device which, by acquiring and analyzing one or more? pictures of 1 pack of cigarettes, ? able to establish whether the band B produced by the double cut 7? been successfully deleted. Obviously, any packets 1 of cigarettes not conforming to the desired specifications (i.e. in which the strip B produced by the double cut 7 has not been correctly eliminated) would be discarded in a waste station located downstream of the control station.

The embodiments described here can be combined with each other without departing from the scope of protection of the present invention.

The unit? 8 cutting method described above has numerous advantages.

Firstly, the unit? 8 cutting described above allows to ensure the removal of the strip B after the double cut 7 avoiding that the strip B (or a piece of the strip B) can remain in contact with the bottom wall 6 of the cigarette pack 1. Furthermore, the unit? 8 cutting described above? simple and economical to implement as compared to a similar unit? of known cutting requires quick modifications using commercial pieces or pieces easily obtainable with standard mechanical processes.

Finally, the unit? 8 cutting described above allows cutting 7 of the back wall 6 to be carried out in a very precise and accurate way, always ensuring optimal functionality. optimal of 1 pack of cigarettes.

LIST OF FIGURE REFERENCE NUMBERS

1 pack of cigarettes

2 rear container

3 front container

4 lid

5 blank

6 back wall

7 cut

8 units? cutting

9 conveyor

10 rotating blades

11 axis of rotation

12 actuator device

13 suction duct 14 fixed guide

15 passing slit

16 pneumatic device 17 support disc

18 rooms

19 outer edge

20 ends? internal

21 pneumatic distributor 22 ends? external

23 through hole

24 cylindrical body

25 compartment

26 compartment

B strap

P path

Claims (15)

1) Unit? (8) cutting to remove a strip (B) from a wall (6) of a package (1), in particular of smoking articles, which is advanced along a path (P); the unit? (8) includes two rotating and coaxial blades (10) which are mounted to rotate around the same rotation axis (11) at a certain distance from each other and make a cut on the wall (6) of the package (1). (7) double that separates the strip (B) from the rest of the wall (6) of the package (1); the unit? (8) cutting ? characterized by the fact that it includes a pneumatic device (16) configured to apply a suction between the two rotating blades (10) which acts on the strap (B). 2) Unit? (8) cutting according to claim 1, wherein the pneumatic device (16) is configured to apply a suction between the two rotating blades (10) which acts on the strap (B) during the execution of the double cut (7). 3) Unit? (8) cutting according to claim 2, wherein the pneumatic device (16) is configured to apply alternately between the two rotating blades (10) a suction that acts on the strip (B) during the execution of the double cut (7) and a breath that acts on the strip (B) after the execution of the cut (7) double. 4) Unit? (8) cutting according to claim 1, 2 or 3 and comprising a support disk (17), which is coaxial to the two rotating blades (10), ? placed between the two rotating blades (10) to form a single assembly with the rotating blades (10), ? mounted rotatable together with the two blades (10) rotating around the rotation axis (11), and delimits at least one chamber (18) which is open towards the outside and in which a suction is applied. 5) Unit? (8) cutting according to claim 4, wherein: the support disk (17) has an external edge (19) which is located between the two rotating blades (10) and is interrupted by an opening in the chamber (18) from which the suction comes out; and in use the strap (B) attracted by the suction rests on the external edge (19) of the support disk (17). 6) Unit? (8) cutting according to claim 4 or 5, wherein the support disk (17) delimits a plurality? of chambers (18) uniformly distributed around the rotation axis (11). 7) Unit? (8) cutting according to claim 4, 5 or 6, wherein the chamber (18) is delimited laterally by the support disk (17) and is delimited above and below by the two rotating blades (10). 8) Unit? (8) cutting according to one of claims 4 to 7, wherein the chamber (18) has an end (20) internal which ? connected to a pneumatic distributor (21) and one end? (22) external which ? radially opposite to the extremity? (20) internal and ? opened through an external edge (19) of the support disk (17). 9) Unit? (8) cutting according to claim 8, wherein at least one rotating blade (10) has a through hole (23) which is placed at the end? (20) inside the chamber (18) of the support disk (17) to connect the chamber (18) to the pneumatic distributor (21). 10) Unit? (8) according to claim 8 or 9, wherein the pneumatic distributor (21) comprises a cylindrical body (24) which is immobile, i.e. it does not rotate around the axis (11) of rotation, it is in contact with a rotating blade (10) against which it slides, and has a first compartment (25) which is shaped like a circular arc, ? coaxial to the axis (11) of rotation, ? connectable to a suction source, and is placed at the end? (20) inside the chamber (18) of the support disc (17). 11) Unit? (8) cutting according to claim 10, wherein the cylindrical body (24) has a second space (26) which is shaped like a circular arc, ? coaxial to the axis (11) of rotation, ? connectable to a source of compressed air, and? placed next to the first compartment (25) at the end? (20) inside the chamber (18) of the support disc (17). 12) Unit? (8) cutting according to one of claims 1 to 11 and comprising a suction duct (13) which is placed next to the rotating blades (10) and is configured to suck the strip (B) which is in contact with the rotating blades (10) themselves. 13) Unit? (8) cutting according to one of claims 1 to 12 and comprising a cleaning device which is arranged in a fixed position around the two rotating blades (10), it is located at a reduced distance from the two rotating blades (10), and has the function of cleaning the two rotating blades (10) from any foreign elements stuck between the two blades (10) themselves or remained attached to a rotating blade (10). 14) Unit? (8) cutting according to one of claims 1 to 13 and comprising a fixed containment guide (14) against which the wall (6) of the package (1) slides and provided with a passing slot (15) through which they are arranged the two rotating blades (10). 15) Cutting method for removing a strip (B) from a wall (6) of a package (1), in particular of smoking articles; the method includes the phases of: advance the packet along a path (P); And make a double cut (7) on the wall (6) of the package (1) which separates the strip (B) from the rest of the wall (6) of the package (1) by means of two rotating and coaxial blades (10) which are mounted to rotate around to the same axis (11) of rotation at a certain distance from each other; the cutting method? characterized by the fact that it includes the further phase of applying a suction between the two rotating blades (10) which acts on the strap (B).