IT202000021748A1 - UNIT AND METHOD OF CUTTING TO REMOVE A STRIP FROM A WALL OF A PACKAGE - Google Patents

Description

DESCRIPTION

of the industrial invention entitled:

"Unit? and method of cutting to remove a strip from a wall of a package"

TECHNICAL SECTOR

The present invention ? relating to a unit? and a cutting method for removing a strip from a wall of a package in particular of smoking articles.

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

EARLIER ART

A pack of cigarettes ?book-pack? comprises (at least) two containers, which house respective groups of wrapped cigarettes, have respective ends top open, and are mutually hinged 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; Moreover, ? expected a lid that ? hinged to a rear container and, when in a closed position, embraces the top of both containers.

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

After folding the third blank ? necessary to make a cut on the back wall of the cigarette packet ?book-pack? to allow the separation of the two containers (or to allow the two containers to rotate with respect to each other); normally a double cut is performed (that is, two close and parallel cuts) to remove a flap (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? cutting what? 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? been separated from the rest of the back wall by a packet of cigarettes ?book-pack?. However, not ? infrequent that even after the cut made by the two rotating blades the strip remains stuck in the back wall of a pack of cigarettes ?book-pack? and therefore is not removed by the suction; consequently, downstream of the unit? cutting some packs of cigarettes ?book-pack? still have the strip on the bottom that can? be more or not in position. This can generate various problems such as the loss of the strip in the machine before applying the transparent plastic overwrap or the wrapping (with the transparent plastic overwrap) of the strip together with the package in completely random positions giving the end user 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 removal of the strip after cutting and, at the same time, is easy and economical to produce.

In accordance with the present invention are provided a unit? and a cutting method for removing a strip from a wall of a package, in particular of smoking articles, according to what is 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

This invention will come now described with reference to the attached drawings, which illustrate a non-limiting embodiment thereof, 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 ?book-pack? of Figure 1 in an open configuration;

? figure 3 ? a plan and schematic view of a unit? cutting to remove a strip from a back wall of the cigarette packet ?book-pack? of figure 1; ? figure 4 ? a perspective view and with the removal of parts for clarity of the unit? cutting of figure 3;

? figure 5 ? a schematic and lateral view of the unit? cutting of figure 3;

? figure 6 ? an enlarged view of a detail of figure 5; And

? figures 7, 8 and 9 are three schematic and plan views of part of the unit? of cut of figure 3 in three respective instants of operation.

PREFERRED EMBODIMENTS OF THE INVENTION

In figures 1 and 2, with the number 1 ? indicated as a whole a pack of cigarettes ?book-pack? comprises two containers 2, which house respective groups of wrapped cigarettes, have respective ends? top open, and are mutually hinged to be able to rotate between a closed configuration (illustrated in figure 1), in which the two containers 2 are superimposed on each other, and an open configuration (illustrated in figure 2), in which the two containers 2 they are separate; Moreover, ? expected a cover 3 that ? hinged to a rear container 2 and, when in a closed position, embraces the top of both containers 2.

The production of pack 1 of ?book-pack? provides for forming the two containers 2 using two corresponding blanks which are folded around the respective groups of wrapped cigarettes, coupling (superimposing) the two containers 2, and then folding around the two coupled (superimposed) containers 2 a third blank which joins the two containers 2 and forms the common lid 3.

After folding the third blank ? necessary to make a cut on the back wall 4 of the cigarette pack ?book-pack? to allow the separation of the two containers 2 (ie to allow the two containers 2 to rotate with respect to each other).

In figures 3 and 4, with the number 5 ? indicated as a whole a unit? which, in order to create a clear separation between the two containers 2, performs a double cut (i.e. two close and parallel cuts) to remove a flap 6 (strip) from the back wall 4 of a pack 1 of cigarettes which is advanced along a straight path P; or the? unit? 5 removes from the bottom wall 4 of a packet 1 of cigarettes a relatively thin central part (the strip 6) to divide the two containers 2. The unit? 5 comprises two parallel and adjacent rotating blades 7 which are arranged horizontally and are mounted for rotation around the same axis 8 of vertical rotation (ie the two rotating blades 7 are identical and coaxial with each other); in use the two rotating blades 7 make two parallel cuts on the bottom wall 4 which separate the strip 6 from the rest of the bottom wall 4.

In the embodiment illustrated in the attached figures, the two rotating blades 7 are parallel to each other, rotate around the same axis 8 of vertical rotation (i.e. they are coaxial) and in use make two parallel cuts on the back wall 4 which separate the strip 6 from the rest of the back wall 4. According to a different and equivalent embodiment not shown, the two rotating blades 7 are inclined with respect to each other (therefore they are both inclined in the opposite way with respect to a horizontal plane), they rotate around two different axes 8 of rotation parallel (and both inclined in an opposite way with respect to a vertical plane), and in use they make on the bottom wall 4 two parallel cuts which separate the strip 6 from the rest of the bottom wall 4. In other words, the two rotating blades 7 are mounted for rotation about respective axes 8 of rotation which can be mutually coincident or different.

According to a further embodiment not shown, the two rotating blades 7 could have a predominantly vertical orientation rather than a predominantly horizontal one as illustrated in the accompanying figures. Furthermore, the two rotating blades 7 may not be perfectly identical to each other (twin) and therefore present differences with respect to each other.

Finally, the two cuts which separate the strip 6 from the rest of the bottom wall 4 and are made by the two rotating blades 7 may not be perfectly parallel to each other (ie they may be slightly convergent or divergent with respect to each other). Furthermore, the unit? 5 includes an extractor element 9, which ? placed near of the two rotating blades 7 to intercept the strip 6 and accompany (push) the strip 6 away from the back wall 4 (obviously on the opposite side of the pack 1 of cigarettes) to separate the strip 6 from the pack 1 of cigarettes.

In particular, the extractor element 9 comprises a point 10 (better illustrated in figures 7, 8 and 9) which first intercepts the strip 6 (that is, it is arranged upstream with respect to the direction of advancement of the pack 1 of cigarettes along the path P ) and has a width smaller than a width of the strip 6 or smaller than a distance between the two rotating blades 7; by way of example, the distance between the two rotating blades 7 (therefore the width of the strip 6) could be approximately 5 tenths of a millimeter while the width of the tip 10 could be approximately 3-4 tenths of a millimetre.

In other words, the? element 9 extractor ? located near of the periphery of the rotating blades 7 so that the tip 10 of the extractor element 9 brushes against the edge of the rotating blades 7 themselves to intercept the strip 6 and accompany the strip 6 away from the back wall 4.

The extractor element 9 has the shape of an arc of circumference and ? mounted for rotation about a rotation axis 11 parallel to the rotation axis 8; in the embodiment illustrated in the attached figures, the axis 11 of rotation of the extractor element 9 ? coaxial (ie coincident) with the axis 8 of rotation of the rotating blades 7 while according to other embodiments the axis 11 of rotation of the extractor element 9 is? parallel and spaced from the axis 8 of rotation of the rotating blades 7.

The unit 5 comprises an actuator device 12 (schematically illustrated in Figure 3) which performs both the rotation of the two blades 7 rotating around the axis 8 of rotation, and the rotation of the extractor element 9 around the axis 11 of rotation. Preferably, the actuator device 12 comprises a first electric motor which rotates the two rotating blades 7 and a second electric motor (mechanically independent from the first electric motor) which rotates the extractor element 9 with a speed of 1.000. of rotation different from the two rotating blades 7; by way of example, the two rotating blades 7 rotate for example at a speed? rotation of about 1500 rpm which always remains constant while the extractor element 9 rotates synchronously with the work cycle of the unit? 5 cutting, or at a speed? of rotation of about 100-400 rpm that ? continuously variable to follow the work cycle of the unit? 5 cutting. According to a different embodiment, the actuator device 12 comprises a single electric motor from which (by means of suitable mechanical transmissions) both the rotation motion of the two blades 7 rotating around the rotation axis 8 and the rotation motion of the ?extractor element 9 around the rotation axis 11.

In the embodiment illustrated in Figures 7, 8 and 9, the actuator device 12 rotates the extractor element 9 between an initial position (illustrated in Figure 8) in which the tip 10 of the extractor element 9 is ? disposed in contact with the bottom wall 4 and a final position (illustrated in figure 9) in which the tip 10 of the extractor element 9 is at a non-zero distance from the back wall 4; this movement of the extractor element 9 progressively away from the back wall 4 allows the strap 6 to be accompanied (pushed) away from the back wall 4 allowing the strap 6 to be adequately separated (extracted) from the back wall 4.

Furthermore, in the embodiment illustrated in figures 7, 8 and 9, the actuator device 12 rotates the extractor element 9 causing the extractor element 9 to perform a working stroke (starting from the position illustrated in figure 7) during which the The extractor element 9 moves along the path P in the same direction as the pack 1 of cigarettes and with a speed? progress lower than a speed? advancement of the pack 1 of cigarettes (so that the extractor element 9 is reached by the oncoming pack 1 of cigarettes and that therefore the extractor element 9 can engage the back wall 4 of the pack 1 of cigarettes), and a stroke return during which the extractor element 9 moves along the path P in an opposite direction with respect to the packet 1 of cigarettes (passing from the position shown in figure 9 to the position shown in figure 7). In other words, in the working stroke the extractor element 9 is located in front of the packet 1 of cigarettes and advances along the path P with a speed? lower than a speed? of the packet 1 of cigarettes in such a way as to be reached by the packet 1 of cigarettes and therefore able to engage the bottom wall 4 of the packet 1 of cigarettes; when the extractor element 9 is reached by the pack 1 of cigarettes and the tip 10 of the extractor element 9 engages the strip 6 (as shown in figure 8), the extractor element 9 moves away from the bottom wall 4 of the pack 1 of cigarettes causing the strip 6 to progressively move away from the bottom wall 4 of the packet 1 of cigarettes (as illustrated in figure 9).

This movement of the extractor element 9 can be done? obtain both if the actuator device 12 rotates the extractor element 9 back and forth (therefore without ever making the extractor element 9 complete a complete turn), and if the actuator device 12 rotates the extractor element 9 always in the same direction (therefore causing the extractor element 9 to complete a succession of complete revolutions). If the actuator device 12 rotates the extractor element 9 back and forth, then the actuator device 12 cyclically reverses the direction of rotation of the extractor element 9 while always keeping the extractor element 9 in the proximity of the extractor element 9. of the path P; on the other hand, if the actuator device 12 always rotates the extractor element 9 in the same direction, then the extractor element 9 completes the return stroke moving away from the path P and passing on the other side of the blades 7 rotating with respect to the path P. Generally ? it is preferable that the actuator device 12 cyclically reverses the direction of rotation of the extractor element 9 (i.e. that the extractor element 9 goes forward and backward) since this law of motion allows only the tip 10 of the extractor element 9 to be made very thin (since it is the only part of the extractor element 9 which must be arranged between the two containers 2) while the rest of the extractor element 9 can? be more wide and therefore mechanically more? robust; on the other hand, when the actuator device 12 always rotates the extractor element 9 in the same direction (thus causing the extractor element 9 to complete a succession of complete turns) the extractor element 9 must be overall more? narrow for reasons of encumbrance and therefore mechanically less robust.

During the working stroke, the extractor element 9 moves along the path P with a speed? (slightly) lower than the speed? of the packet 1 of cigarettes, therefore the impact between the tip 10 of the extractor element 9 and the back wall 4 occurs at a low speed? relative (therefore in a gentle and non-traumatic way).

According to a different embodiment not shown, the extractor element 9 could not perform any movement along the path P and in this case the impact between the tip 10 of the extractor element 9 and the back wall 4 takes place at speed relative pi? high (the extractor element 9 is stationary with respect to the path P, therefore the impact occurs at the speed of the pack 1 of cigarettes); this variant can? expose the back wall 4 to some risk of suffering unwanted dents on impact with the tip 10 of the extractor element 9 but ? however possible. In this embodiment, the extractor element 9 could maintain movement along a direction perpendicular to the path P between the initial position (illustrated in Figure 8) in which the tip 10 of the extractor element 9 ? disposed in contact with the bottom wall 4 and the final position (shown in figure 9) in which the tip 10 of the extractor element 9 is? at a non-zero distance from the back wall 4; alternatively, the extractor element 9 could be completely stopped, i.e. it could not move nor? parallel to path P, n? perpendicular to path P.

In the embodiment illustrated in the attached figures, the actuator device 12 imparts to the extractor element 9 a rotation movement about the rotation axis 11; according to a different embodiment not shown, the actuator device 12 imparts to the extractor element 9 a linear translation movement along a direction parallel to the path P (to alternatively perform the working stroke and the return stroke) and also along a direction perpendicular to the path P (to move between the start position and the end position).

According to what is illustrated in figures 3 and 4, the unit? 5 includes a suction duct 13 (that is connected to a suction source) arranged to suck the strip 6 which? been pushed away from the back wall 4 by the extractor element 9. In detail, the suction duct 13 has one end Initial 14 what? disposed in correspondence with the rotating blades 7 and ? configured to contain at least a portion of the extractor element 9; in other words, the element 9 extractor moves inside the extremity? 14 of the suction duct 13. The function of the suction duct 13 ? to convey by suction the strip 6 that ? been separated from the back wall 4 so as to bring the strip 6 to a suitable collection area (not shown). By way of example, the suction in the suction duct 13 can be created using an impeller or a flow accelerator. In particular, the? Extremity? 14 of the suction duct 13 has an inlet opening 15 which ? facing the back wall 4 and through which the extractor element 9 passes.

According to a preferred embodiment, the? 14 of the suction duct 13 has a conical shape having the minimum size in correspondence with the inlet opening 15 (i.e. having a dimension that progressively widens moving away from the rotating blades 7 so as to have the maximum depression in correspondence with the rotating blades 7) .

According to a possible embodiment illustrated in figure 4, the unit? 5 includes a cleaning device 16 (ie a sort of scraper) which? arranged in a fixed position around the two rotating blades 7, it is located at a reduced distance from the two rotating blades 7, and has the function of cleaning the two rotating blades 7 from any foreign elements (pieces of cardboard on the back wall 4) that have become stuck between the two rotating blades 7 or stuck to a rotating blade 7. In other words, the cleaning device 16 separates from the rotating blades 7 any extraneous elements (pieces of cardboard of the back wall 4) stuck between the two rotating blades 7 or stuck to a rotating blade 7.

As illustrated in figures 3 and 4, the packet 1 of cigarettes is advanced along the path P by a conveyor provided with two fixed containment guides 17 between which the packet 1 of cigarettes is located; in particular, a fixed guide 17 against which the back wall 4 slides? provided with a through opening through which the two rotating blades 7 are arranged (for this purpose, the through opening of the fixed guide 17 is slightly wider than the pair of rotating blades 7 to allow their insertion beyond the fixed guide 17 with a minimum game).

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

The unit 1 of cutting described above has numerous advantages.

Firstly, the unit? 1 of cut described above allows to ensure the removal of the strip 6 after the cut avoiding that the strip 6 (or a piece of the strip 6) can remain in contact with the bottom wall 4 of the packet 1 of cigarettes.

Furthermore, the unit? 1 cutting described above ? of simple and economic construction as compared to a similar unit? of known cut requires quick modifications using commercial pieces or pieces that can be easily obtained with standard mechanical machining.

Claims (16)

1) Unit? (5) cutting to remove a strip (6) from a wall (4) of a package (1), in particular of smoking articles, which is advanced along a path (P); the unit? (5) comprises two rotating blades (7) which are mounted to rotate around respective axes (8) of rotation and make two cuts on the wall (4) of the package (1) which separate the strip (6) from the rest of the wall (4) of package (1); the unit? (5) cutting ? characterized in that it comprises an extractor element (9), which ? placed near of the two rotating blades (7) to intercept the strip (6) and accompany the strip (6) away from the wall (4). 2) Unit? (5) according to claim 1, wherein the extractor element (9) comprises a tip (10) which first intercepts the strip (6) and has a width smaller than a width of the strip (6) or smaller than a distance between the two rotating blades (7). 3) Units (5) cutting according to claim 1 or 2, wherein: the element (9) extractor ? mounted mobile along a first direction perpendicular to the path (P) and to the wall (4) of the package (1); and ? provided is an actuator device (12) which moves the extractor element (9) along the first direction between an initial position in which a tip (10) of the extractor element (9) ? disposed in contact with the wall (4) of the packet (1) and a final position in which the tip (10) of the extractor element (9) is at a non-zero distance from the wall (4) of the package (1). 4) Units (5) according to claim 1, 2 or 3, wherein the extractor element (9) is? mounted mobile along a second direction parallel to the path (P) and to the wall (4) of the package (1); and ? an actuator device (12) is provided which moves the extractor element (9) along the second direction causing the extractor element (9) to perform a working stroke during which the extractor element (9) moves along the second direction with the same direction of the package (1) and with a speed? progress lower than a speed? advancement of the packet (1), and a return stroke during which the extractor element (9) moves along the second direction with an opposite direction with respect to the packet (1). 5) Units (5) cutting according to one of claims 1 to 4, wherein: the element (9) extractor ? mounted rotatably about a second axis (11) of rotation parallel to the first axis (8) of rotation; and ? an actuator device (12) is provided which rotates the extractor element (9) around the second rotation axis (11) alternatively in both directions or always in the same direction. 6) Units (5) according to claim 5, wherein the actuator device (12) rotates the stripper element (9) between an initial position in which a tip (10) of the stripper element (9) ? disposed in contact with the wall (4) of the packet (1) and a final position in which the tip (10) of the extractor element (9) is at a non-zero distance from the wall (4) of the package (1). 7) Units (5) according to claim 5 or 6, wherein the actuator device (12) rotates the extractor element (9) causing the extractor element (9) to perform a working stroke during which the element (9) extractor moves along the path (P) with the same direction of the packet (1) and with a speed? progress lower than a speed? advancement of the packet (1), and a return stroke during which the extractor element (9) moves along the path (P) in an opposite direction with respect to the packet (1). 8) Units (5) according to claim 5, 6 or 7, wherein the stripper element (9) has the shape of a circumferential arc. 9) Units (5) of cutting according to one of claims 5 to 8, wherein the first rotation axis (8) is? coaxial to the second axis (11) of rotation. 10) Units (5) according to one of claims 5 to 9, wherein the actuator device (12) comprises a first electric motor which rotates the two blades (7) rotating around the first rotation axis (8) and a second electric motor which rotates the extractor element (9) around the second rotation axis (11) independently of the rotation of the two rotating blades (7). 11) Units (5) according to one of the claims from 1 to 11 and comprising a suction duct (13) arranged to suck the strip (6) which is been pushed away from the wall (4) by the extractor element (9). 12) Units (5) according to claim 11, wherein the suction duct (13) has one end? (14) initial that ? arranged in correspondence with the rotating blades (7) and ? configured to contain at least a portion of the extractor element (9). 13) Units (5) cutting according to claim 12, wherein the? (14) of the suction duct (13) has an inlet opening (15) which ? facing the wall (4) of the package (1) and through which the extractor element (9) passes. 14) Units (5) according to one of claims 1 to 13 and comprising a cleaning device (16) which ? arranged in a fixed position around the two rotating blades (7), it is located at a reduced distance from the two rotating blades (7), and has the function of cleaning the two rotating blades (7) from any foreign elements stuck between the two blades (7) rotating themselves or stuck to a rotating (7) blade. 15) Units (5) according to one of the claims from 1 to 14 and comprising a fixed containment guide (17) against which the wall (4) of the package (1) slides and provided with a through opening through which the two blades are arranged (7) rotating. 16) Cutting method for removing a strip (6) from a wall (4) of a package (1), in particular of smoking articles; the method includes the phases of: advance the packet along a path (P); And make two cuts on the wall (4) of the package (1) which separate the strip (6) from the rest of the wall (4) of the package (1) by means of two rotating blades (7) which are mounted revolving around respective axes (8) of rotation; the cutting method? characterized in that it comprises the further step of intercepting the strip (6) and accompanying the strip (6) away from the wall (4) by means of an extractor element (9) arranged near the wall (4). of the two rotating blades (7).