PACKAGING MACHINE AND METHOD FOR PACKING CIGARETTES Technical field

This invention relates to a packaging machine and method for packing cigarettes in a packet.

More specifically, this invention addresses a cigarette packet comprising an outer wrapper made of foldable card which houses a group of cigarettes wrapped in an inner wrapper which is generally metallized. More precisely, the term "foldable card" is used to denote a soft-rigid card, that is, a card which is neither rigid like the card preferably used for hinged-lid packets, nor soft like the card preferably used to make soft packets.

The grammage of the foldable card of this type is in the order of 140-220 gr/m ²

Background art

Generally speaking, the soft-rigid foldable card of this type of cigarette packet is wrapped around the side walls and bottom wall of the group of cigarettes, leaving the top of the group uncovered with a rectangular stamp or state revenue stamp placed astride of it.

This foldable card, however, has a disadvantage. Indeed, if it is not weakened along the fold lines before being folded around the respective group, it tends to curve or "bulge out" sideways without adhering to the side walls of the group, and the longitudinal and transversal edges are not perfectly square, with a generally negative effect on the quality of the packet.

To overcome this disadvantage, packaging machine for packing cigarettes are known which comprise means for weakening the foldable card along the fold lines.

The weakening means comprise rollers and counter-rollers acting in combination to feed and weaken the foldable card along the fold lines. It has been found, however, that the combined action of the rollers and counter-rollers is unable to weaken or stress-relieve the foldable card enough to prevent the above mentioned quality defects when wrapped around the group of cigarettes.

Aim of the invention

This invention has for an aim to provide a packaging machine and method, for the tobacco machinery industry, for packing cigarettes in a packet, which is free of the above mentioned disadvantages, and as set out in the independent claims 1 and 19.

Brief description of the drawings

The invention is described below with reference to the accompanying drawings, which illustrate a non-limiting embodiment and in which:

- Figure 1 is a schematic perspective view of a packaging machine according to this invention for packing cigarettes in packets;

- Figure 2 is a scaled-up schematic perspective view of a detail of the machine of Figure 1 , with some parts cut away in order to better illustrate others;

- Figure 3 is a scaled-up schematic front view of a detail of the machine of Figure 1 ;

- Figure 4 is a schematic perspective view illustrating some steps in the operation of the machine shown in Figure 1 ;

- Figure 5 is a schematic perspective view of a packet which can be made by the machine according to the invention; - Figure 6 is a schematic perspective view of a blank from which the outer wrapper of the packet of Figure 5 is made;

- Figure 7 is a schematic perspective view illustrating some alternative steps in the operation of the machine shown in Figure 1 .

Detailed description of preferred embodiments of the invention

With reference to Figure 1 , the numeral 1 denotes a packaging machine for packing cigarettes in packets 2.

More specifically, the packet 2, illustrated in Figure 5, comprises a group 3 of cigarettes, wrapped in an inner wrapper 4, and an outer wrapper 5, in particular made of foldable thin cardboard, enclosing the group 3 of cigarettes, in particular the inner wrapper 4 of the group 3.

Preferably, the inner wrapper 4 of the group 3 of cigarettes is made of a metallized material.

The packet 2 has a front wall 6, a rear wall 7, a bottom wall 8, a top wall 9 and two flanks 10.

More specifically, the front wall 6, the rear wall 7, the bottom wall 8, and the two flanks 10 are defined by the outer wrapper 5 enclosing the group 3 of cigarettes and the top wall 9 is defined by the top wall of the inner wrapper 4 wrapped around the group 3 of cigarettes.

In other words, the outer wrapper 5 is wrapped all around the group 3 of cigarettes except for the top wall 9 which is defined by the group 3 itself. Thus, the packet 2 does not have a hinged lid.

The outer wrapper 5 is formed from a blank, illustrated in Figure 6, which comprises a plurality of fold lines 1 1 , 12, 13, 14, 15 which delimit a plurality of panels designed to form the respective walls of the packet 2, and which will constitute the longitudinal and transversal edges of the selfsame packet 2.

The outer wrapper 5 has a main axis 5a of extension. More specifically, the outer wrapper 5 comprises a first, a second, a third and a fourth fold line 1 1 , 12, 13, 14, transversal to the axis 5a, and a fifth fold line 15 parallel to the axis 5a.

More precisely, the first and second fold lines 1 1 , 12 and the fifth fold line 15 define a first panel 16 which will form the front wall 6 of the packet 2. The second and third fold lines 12, 13 and the fifth fold line 15 define a second panel 17 which will form one of the flanks 10 of the packet 2.

The third and fourth fold lines 13, 14 and the fifth fold line 15 define a third panel 18 which will form the rear wall 7 of the packet 2.

The first and fourth fold lines 1 1 , 14 and the fifth fold line 15 define respective fourth and fifth panels 19, 20 which will form one of the flanks 10 of the packet 2.

From the fifth fold line 15 there extends a plurality of wings or bottom panels which will form the bottom wall 8 of the packet 2.

The first, second, third, fourth and fifth panels 16, 17, 18, 19, 20 are connected to each other in sequence by respective fold lines 1 1 , 12, 13,

14.

The first, second, third, fourth and fifth panels 16, 17, 18, 19, 20 are each connected to a respective wing or bottom panel 30 by the fifth fold line 15. The machine 1 comprises a station 21 for feeding the outer wrapper 5 and a station 22, located downstream of the feed station 21 , for folding the outer wrapper 5 along the fold lines 1 1 , 12, 13, 14, 15 around a respective group 3 of cigarettes, thereby wrapping the selfsame group 3 of cigarettes to make the finished packet 2.

The machine 1 comprises a device 23 for weakening the outer wrapper 5 along the fold lines 1 1 , 12, 13, 14, 15 and positioned between the feeding station 21 and the folding station 22.

The weakening device 23 comprises a rectilinear feed line 24 along which the outer wrappers 5 are conveyed, fed by the feeding station 21 .

The outer wrappers 5 are conveyed along a feed direction D parallel to the direction of extension of the feed line 24, as indicated by the arrow F in Figure 1 .

The rectilinear feed line 24 comprises at least two sections T1 , T2, in particular a first and a second section, distinct from each other.

The weakening device 23 comprises transfer means 31 by which the outer wrapper 5 is transferred from the first section T1 to the second section T2. The outer wrapper 5 advances along the first and second sections T1 , T2 according to a first configuration and a second configuration, respectively, the second configuration differing from the first configuration relative to the feed direction D.

In other words, the outer wrapper 5 advances along the first section T1 oriented with its main axis 5a of extension at right angles to the feed direction of the first section T1 , that is, in the first configuration, and along the second section T2 oriented with its main axis 5a of extension parallel to the feed direction of the second section T2, that is, in the second configuration.

In an alternative variant embodiment not illustrated, the outer wrapper 5 advances along the first section T1 oriented with its main axis 5a of extension parallel to the feed direction of the first section T1 and along the second section T2 oriented with its main axis 5a of extension at right angles to the feed direction of the second section T2.

More precisely, as illustrated in Figures 1 , 2 and 4, the rectilinear feed line 24 comprises at least two consecutive sections, namely, the first and the second section T1 , T2, at right angles to each other.

In this embodiment, the first and second sections T1 , T2 have respective feed directions D at right angles to each other.

The machine 1 comprises means 25 for folding the outer wrapper 5, positioned along the feed line 24 and capable of weakening the outer wrapper 5 along the fold lines 1 1 , 12, 13, 14, 15 parallel to the feed direction D. The folding means 25 are positioned along the first and the second section T1 , T2 to weaken the fold lines 1 1 , 12, 13, 14, 15 parallel to the feed direction D of the first and the second section T1 , T2, respectively. In the embodiment illustrated, along the first section T1 of the feed line 24, the outer wrapper 5 is weakened along the first, second, third and fourth fold lines 1 1 , 12, 13, 14.

Along the second section T2 of the feed line 24, the outer wrapper 5 is weakened along the fifth fold line 15.

The folding means 25 engage respective portions of the panels 16, 17, 18, 19, 20, 30 of each outer wrapper 5 while it advances along the feed line 24.

More specifically, the folding means 25 drive in relative rotation the panels 16, 17, 18, 19, 20, 30 of the outer wrapper 5 along the respective fold lines 1 1 , 12, 13, 14, 15 taking the panels 16, 17, 18, 19, 20, 30 from an initial position to a final position and vice versa taking the panels 16,

17, 18, 19, 20, 30 back to the initial position.

It should be noted that the folding means 25 weaken the outer wrapper 5 along a respective fold line 1 1 , 12, 13, 14, 15 defining the panel 16, 17,

18, 19, 20, 30 engaged by the selfsame folding means 25.

By initial position is meant a position where a respective panel 16, 17, 18,

19, 20, 30 of the outer wrapper 5 lies flat.

By final position is meant the position where a respective panel 16, 17, 18, 19, 20, 30 of the outer wrapper 5 lies when it has reached the maximum folding angle a under the action of the folding means 25.

Advantageously, from the initial position to the final position, the folding means 25 act on the respective panel 16, 17, 18, 19, 20, 30 to rotate it by an angle greater than 90°, in particular and preferably up to 135°, so as to weaken the respective outer wrapper 5 along the fold lines 1 1 , 12, 13, 14, 15.

The folding means 25 are integral with the weakening device 23 and are relatively fixed with respect to the movement of the feed line 24.

The folding means 25 comprise at least one spiral-shaped profile 25b equipped with a respective opposing or abutment element 25a.

The spiral-shaped profile 25b and the respective opposing element 25a are parts that remain fixed relative to the feed line 24.

In practice, the folding means 25 lift and lower the panels 16, 17, 18, 19,

20, 30 relative to the position where the outer wrapper 5 lies flat.

The folding means 25 act on the respective panels 16, 17, 18, 19, 20, 30 of each outer wrapper 5 when the outer wrapper is being conveyed along the feed line 24.

In other words, the outer wrappers 5 interact with the folding means 25 by interference therewith while they are being conveyed along the feed line 24.

Advantageously, the spiral-shaped profile 25b engages a respective panel 16, 17, 18, 19, 20, 30 of the outer wrapper 5 to rotate it along the fold line 1 1 , 12, 13, 14, 15 until reaching an angle of rotation a of 135° where the panel is at the final position.

The spiral-shaped profile 25b is shaped in such a way as to take the panels 16, 17, 18, 19, 20, 30 back from their final position to their initial position, in particular by rotating them by 135° in the opposite direction of rotation.

Along the first section T1 , the feed line 24 comprises a conveyor belt 26 for retaining and transporting the outer wrappers 5.

The conveyor 26 comprises a pair of distinct suction belts, separated by a space, and a plurality of side walls 27, integral with the suction belts, which define respective compartments 28 for positioning and housing respective outer wrappers 5. In particular, two consecutive side walls 27 define a respective compartment 28.

Each outer wrapper 5 is positioned in a respective compartment 28 of the conveyor 26 and held down on the suction belts by suction means 38. More precisely and preferably, the suction means 38 act on the second panel 17 and on the fourth panel 19 of each outer wrapper 5.

The side walls 27 are positioned in a direction transversal to the feed direction D of the outer wrappers 5. More specifically, each side wall 27 has one or more recesses 29 in which the respective folding means 25 are positioned, as illustrated in Figure 3, while the conveyor 26 advances. More specifically, each side wall 27 has as many recesses 29 as there are fold lines 1 1 , 12, 13, 14 parallel to the feed direction D.

In other words, each recess 29 is designed to house a respective spiral- shaped profile 25b equipped with a respective opposing element 25a while the conveyor 26 advances.

Thus, each recess 29 houses a respective folding means 25 which acts on a respective panel 16, 17, 18, 19, 20 to weaken each outer wrapper 5 along the respective fold line 1 1 , 12, 13, 14 defining the panel itself.

Along the first section T1 of the feed line 24, the folding means 25 comprise fixed spiral-shaped profiles 25b equipped with respective opposing elements 25a having a respective engagement surface shaped to rotate a respective panel 16, 17, 18, 19, 20 along the respective fold line 1 1 , 12, 13, 14 from the initial position to the final position, and vice versa.

In practice, the folding means 25 lift and lower a respective panel 16, 17, 18, 19, 20 relative to the position where the outer wrapper 5 lies flat as the outer wrapper 5 itself, housed in the compartment 28 of the conveyor 26, advances along the direction D.

It should be noted that the moment the folding means 25 engage the second or fourth panel 17, 19 the suction hold-down action of the suction means 38 on the second or fourth panel 17, 19 is interrupted.

Preferably, in order to weaken the outer wrapper 5 as it advances along the first section T1 of the feed line 24, the conveyor 26 advances with intermittent motion. The second section T2 of the feed line 24 comprises a suction conveyor belt 39 which advances with continuous motion.

Advantageously, in order to synchronize the intermittent motion of the first section T1 with the continuous motion of the second section T2, the first section T1 of the feed line 24 lies in a first plane and the second section T2 of the feed line 24 lies in a second plane, different from the first plane. More specifically, the first plane is at a level lower than the second plane. The weakening device 23 comprises lifting means 31 which transfer each outer wrapper 5 from the first section T1 to the second section T2, lifting them from the first to the second plane.

It should be noted that the lifting means 31 constitute the aforementioned transfer means.

The lifting means 31 are located along the conveyor 26 at the end of the first section T1 of the feed line 24.

Preferably, the lifting means 31 comprise a rocker arm 32 which oscillates about its axis 32a, and a retaining element 33, connected to the arm 32, which transports a respective outer wrapper 5 held by it from the first to the second plane.

For this purpose, the retaining element 33 is equipped with a plurality of supports which come into abutment against the outer wrappers 5 passing in the space between and on the outside of the two suction belts, as illustrated in Figure 2 where, for clarity, the pair of suction belts is not shown. The supports may consist of suction gripper heads.

As illustrated in Figure 2, the lifting means 31 are movable, by oscillation of the arm 32, from the first to the second plane, lifting a respective outer wrapper 5, and from the second to the first plane to receive from the conveyor belt 26 the next outer wrapper 5 to be lifted.

In other words, the lifting means 31 are movable from a station 36 for receiving the outer wrappers 5 to be lifted to a station 35 for releasing the outer wrappers 5 which have been lifted. Advantageously, in order to correctly orient and position the outer wrappers 5 at the second section T2 of the feed line 24, the weakening device 23 comprises a positioner 34 located at the releasing station 35. The positioner 34 acts in conjunction with the lifting means 31 to orient the outer wrapper 5 in a direction parallel to its main axis 5a of extension. In effect, since the first and second sections T1 and T2 are at right angles to each other, the outer wrapper 5 advances along the first section T1 oriented with its main axis 5a of extension at right angles to the feed direction of the first section T1 and along the second section T2 oriented with its main axis 5a of extension parallel to the feed direction of the second section T2.

The positioner 34 has two abutment surfaces 34a and 34b facing each other and each of which is designed to come into contact with a respective end edge 40 of a respective outer wrapper 5. More specifically, it comes into contact with the end edges 40 parallel to the main axis 5a of extension of each outer wrapper 5.

Preferably, the abutment surfaces 34a and 34b each have an edge 41 extending in a direction parallel to the feed direction of the second section T2.

Abutment between the end edges 40 of an outer wrapper 5 and the respective edge 41 of the abutment surfaces 34a and 34b guarantees correct positioning of the outer wrapper 5.

It should be noted that to insert an outer wrapper 5 in the positioner 34, the lifting means 31 lift the respective outer wrapper 5 until the end edges 40 engage the respective edge 41 of the abutment surfaces 34a and 34b, flicking elastically past the lower edge of each of the abutment surfaces 34a and 34b themselves.

Once the outer wrapper 5 has been placed in the positioner 34, feed means 37 transfer each outer wrapper 5 from the positioner 34 to the conveyor 39 of the second section T2 of the feed line 24. The conveyor 39 feeds the outer wrappers 5 continuously along the second stretch T2 of the feed line 24.

As stated above, along the second section T2 of the feed line 24, the outer wrapper 5 is weakened along the fifth fold line 15.

The folding means 25 located along the second section T2 of the feed line 24 comprise a roller and a counter-roller, acting in conjunction, and a fixed spiral-shaped profile, not illustrated, equipped with an abutment element, not illustrated, located downstream of the roller and counter- roller.

More precisely, the roller and counter-roller engage the wings 30 of a respective outer wrapper 5 rotating them along the fifth fold line 15 preferably by up to 90° relative to their initial position.

Next, the fixed spiral-shaped profile, not illustrated, engages the wings 30 further rotating them along the fifth fold line 15, preferably up to 135°, taking them to their final position.

The spiral-shaped profile, not illustrated, is shaped in such a way as to take the wings 30 back from their final position to their initial position, in particular by rotating them by 135° in the opposite direction of rotation In practice, the folding means 25 lift and lower the wings 30 relative to the position where the outer wrapper 5 lies flat.

The feed means 37 may comprise a toothed belt driven by two pulleys and two rollers acting in conjunction along a common line of tangency, as illustrated in Figure 1 .

Downstream of the folding means 25 located along the second section T2, the outer wrapper 5 is weakened along the fold lines 1 1 , 12, 13, 14, 15 parallel and transversal to its main axis 5a of extension.

On leaving the weakening device 23, the outer wrappers 5 are fed to the folding station 22, where each outer wrapper 5 is folded along the fold lines 1 1 , 12, 13, 14, 15 around a respective group 3 of cigarettes, thus making the packet 2. In use, the folding means 25 are located along the feed line 24 according to a configuration such as to weaken the outer wrapper 5 according to a predetermined sequence, as illustrated in Figure 4.

Preferably, the sequence illustrated entails first weakening the third fold line 13 by acting on the third panel 18.

Next, the second fold line 12 is weakened by acting on the first panel 16. At this point, the second and third fold lines 12 and 13 of the second panel 18 by which the latter is connected to the second and fourth panels 17 and 19, respectively, have been weakened.

Next, the first and fourth fold lines 1 1 , 14 are weakened, preferably simultaneously, by acting on the fourth and fifth panels 19, 20.

Lastly, the fifth fold line 15 is weakened by acting on the bottom panels or wings 30.

In the variant embodiment of the machine 1 illustrated in Figure 7, the first and second sections T1 , T2 have the same feed direction D.

More specifically, the first and second sections T1 and T2 are aligned. More specifically, in this variant embodiment, the first and second sections T1 , T2 lie in the same plane.

In this variant embodiment, the transfer means 31 are in the form of a turntable which rotates alternately about its axis of rotation 31 a.

More specifically, the axis of rotation 31 a of the turntable is a vertical axis. When picked up by the transfer turntable 31 from the first section T1 , the outer wrapper 5 is positioned according to a first configuration and when released onto the second section T2, the outer wrapper 5 is positioned according to a second configuration, different from the first configuration relative to the feed direction D.

In this embodiment, when the outer wrapper 5 is positioned according to the first configuration, its main axis 5a of extension is parallel to the feed direction D and when positioned according to the second configuration, its main axis 5a of extension is transversal to the feed direction D. In this embodiment, considering that the first and second sections T1 , T2 have the same feed direction D, the transfer means 31 , in particular in the form of a turntable, change the orientation of the outer wrapper 5 from the first to the second configuration.

More specifically, during the passage from the first to the second configuration, the outer wrapper 5 is rotated by the turntable 31 by 90°. This invention also relates to a packaging method for the tobacco machinery industry, for packing cigarettes in a packet 2.

The method comprises the step of feeding an outer wrapper 5 for a respective group 3 of cigarettes and the step of folding the outer wrapper 5 around a respective group 3 of cigarettes along the fold lines 1 1 , 12, 13, 14, 15 to make the packet 2.

The method comprises a step of weakening the outer wrapper 5 along the fold lines 1 1 , 12, 13, 14, 15 before the step of wrapping the outer wrapper 5 around the group 3 of cigarettes.

Advantageously, the method comprises a step of feeding the outer wrapper 5 along a rectilinear feed path during the step of weakening the outer wrapper 5.

The step of feeding the outer wrapper 5 comprises a step of feeding the outer wrapper 5 along at least two sections T1 , T2, in particular a first and a second section, distinct from each other.

During the step of feeding along the first and second sections T1 , T2, the outer wrapper 5 advances according to a first configuration and a second configuration, respectively, the second configuration differing from the first configuration relative to the feed direction D.

More specifically, as it advances during the step of feeding along the first section T1 , the outer wrapper 5 is oriented with its main axis 5a of extension at right angles to the feed direction and as it advances during the step of feeding along the second section T2 the outer wrapper 5 is oriented with its main axis 5a of extension parallel to the feed direction of the second section T2, or vice versa.

The method comprises a step of transferring the outer wrapper 5 from the first section T1 to the second section T2.

More specifically, the step of weakening the outer wrapper 5 along the fold lines 1 1 , 12, 13, 14, 15 comprises a step of rotating the panels 16, 17, 18, 19, 20, 30 along the respective fold lines 1 1 , 12, 13, 14, 15.

The step of weakening the outer wrapper 5 along the fold lines 1 1 , 12, 13, 14, 15 comprises a step of rotating the respective panel 16, 17, 18, 19, 20, 30 according to an angle of rotation a greater than 90°, in particular up to 135°.

More specifically, the step of weakening the outer wrapper 5 occurs along the fold lines 1 1 , 12, 13, 14, 15 positioned parallel to the feed direction D of the wrapper 5.

As illustrated in Figures 1 , 2 and 4, the step of feeding the outer wrapper 5 occurs along two or more feed sections T1 , T2, one section being at right angles to the next.

In other words, the step of feeding the outer wrapper 5 occurs along the first and second sections T1 , T2 which have respective feed directions D at right angles to each other.

To pass from the first section T1 to the second section T2, the method comprises a step of raising the outer wrapper 5 at the point where the feed direction changes between the first and the second section T1 ,T2. In the variant embodiment illustrated in Figure 7, the step of feeding the outer wrapper 5 is performed along the first and second sections T1 , T2 having the same feed direction D.

To pass from the first section T1 to the second section T2, the method comprises a step of rotating each outer wrapper 5 during the step of transferring the outer wrapper 5 from the first section T1 to the second section T2. More specifically, during the step of rotating each outer wrapper 5, the latter is rotated by 90° during the passage from the first to the second configuration.

In both embodiments, the outer wrapper 5 is conveyed along the first section T1 of the feed line 24 with intermittent motion and along the second section T2 with continuous motion.

This invention overcomes the disadvantages of the prior art in that the force applied to the outer wrapper 5 when it leaves the weakening device 23 to wrap and fold it around the group 3 of cigarettes is relatively low compared to the prior art.

That is because, advantageously, along a rectilinear feed path 24, it is possible to weaken the fold lines 1 1 , 12, 13, 14, 15 by relatively rotating the respective panels 17, 18, 19, 20, 30 by more than 90° and at least up to 135° relative to the plane in which the outer wrapper 5 itself lies.

Moreover, once the packet 2 has been made, the outer wrapper 5 wrapped around the group 3 of cigarettes has longitudinal and transversal edges which are perfectly square and without sideways curves or "bulges" since the outer wrapper 5 adheres to the group 3.