PL233529B1 - Method of packing and the packing unit for making the sealed inner package - Google Patents

Description

Description of the invention

The invention relates to a packaging method and a packaging unit for producing a sealed inner package.

The present invention is preferably applied to a cigarette pack having a sealed inner package to which the description below will be expressly referred to without losing its generality.

A cigarette packet generally comprises an inner packet that is formed by a group of cigarettes wrapped in an inner sheet of wrapping material and an outer sheath that surrounds the inner pack and may be made of an outer sheet of wrapping material folded around a cup-shaped inner packet (soft cigarette packet). ) or it may be made of a rigid box with a hinge lid formed by folding the rigid blank around an inner package (rigid cigarette pack).

In a conventional cigarette pack, the group of cigarettes is internally wrapped with a rectangular inner sheet of metallized paper packing material without adhesive and is wrapped externally with a rectangular outer sheet of packing material stabilized by gluing.

Tobacco is very sensitive to the influences of the external environment, as contact with the atmosphere tends to change its organoleptic properties, both in the case of the influence of changes in humidity (the tobacco may dry out too much or may absorb too much moisture) and in the event of the evaporation of volatile substances with which the tobacco has been impregnated ( especially for flavored cigarettes with particular flavors such as cloves). To maintain the integrity of the cigarette tobacco, the cigarette packs are wrapped in cellophane, that is, they are coated with an impermeable sealed outer plastic wrapper. However, a heat-sealed outer wrapper may not be sufficient to completely preserve the organoleptic characteristics of the tobacco contained in a cigarette pack, especially when the cigarette pack is used up some time after manufacture. Moreover, when the package is first opened, the outer top wrap is removed, so that the cigarette tobacco contained in the package is in contact with the outside; if the cigarettes contained in the pack are not used up quickly after the pack is first opened, the organoleptic properties of the remaining cigarettes may deteriorate.

To overcome the above-described drawback, US4300676A1 proposes a rigid cigarette pack in which the inner package is impermeable and is made of a sheet of impermeable and heat-sealable packaging material having a cigarette removal opening which is closed by a reusable closure flap. However, the sealed inner package described in patent US4300676A1 has a slight sealing, i.e. it does not provide a sufficient degree of sealing to effectively isolate the cigarette tobacco contained in the package from the outside environment.

To increase the degree of tightness of the sealed inner package, so-called "fin tabs" can be used by folding the two flaps of the inner sheet of packaging material together so as to overlap the two flaps and form a fin perpendicular to the group of cigarettes below the wall. Some examples of cigarette inner packets having "fin tabs" are described in the following documents: EP2544958A1, EP2456685A1, EP1686060A1, US4789060A1, US2011084120A1, GB1471086A1 and US3948389A1.

Document US2011120903A1 discloses a method and machine for forming a sealed wrapper around an article in which a sheet of wrapping material is folded and sealed around the article to form an essentially tubular, partial wrapper having two open ends and a sealing flap extending outward transversely to the partial wrap; the sealing flap is folded over the major side portion of the partial wrap; and the open ends of the partial wrap are then gripped and sealed.

However, making "fin tabs" according to currently known packaging methods requires complex, and therefore very expensive, packaging units.

The object of the present invention is to provide a packaging method and a packaging unit for producing a sealed inner package, which method and assembly are free from the above-described drawbacks and at the same time are easy and inexpensive to implement.

A method of packaging for producing a sealed inner package that surrounds a product, preferably containing tobacco products, and having a front wall, a rear wall, two walls.

Side, bottom wall and top wall; the packaging method comprises the steps of: folding a sheet of heat sealable packaging material around the product to form a tubular wrapper having two open ends located on side walls each having two opposite side flaps extending from the product; folding the two side flaps of the sheet of wrapping material at each open end of the tubular wrapper towards each other so as to overlap the two side flaps and form a longitudinal fin perpendicular to the underlying sidewall; welding the two superposed side flaps of each longitudinal fin to each other to stabilize the longitudinal fin; folding each longitudinal fin through an angle of 90 ° to the respective side wall; and folding the two projections of each longitudinal fin through an angle of 180 ° onto the longitudinal fin and around the respective transverse edges of the respective sidewall; wherein the step of folding the sheet of packing material to form the tubular wrapper further comprises the steps of: folding the sheet of packing material into a "U" shape around the product to form a first bottom flap flush with the front wall and protruding from the bottom wall; and a second bottom flap that is flush with the rear wall and projects from the bottom wall; folding the two bottom flaps through an angle of 90 ° and in the same direction around the respective transverse edges of the bottom wall so as to overlap the two bottom flaps and form a transverse fin that is parallel to the bottom wall, has an inner edge located at the transverse edge of the bottom wall, and an outer edge located outside the product and at a certain distance from the product; and welding the two superposed lower flaps to each other to stabilize the transverse fin; wherein the step of folding the sheet of packaging material to form the tubular wrap is performed while conveying the product through a pocket on the first packaging wheel rotatably mounted about the first rotation axis; and wherein the step of folding the side flaps of the sheet of packing material to form longitudinal fins and the step of welding the overlapping side flaps of each longitudinal fin together are performed while conveying the product through a straight packing conveyor located immediately downstream of the first packing wheel; the packaging method according to the invention is characterized in that the step of folding each longitudinal fin by an angle of 90 ° and the step of folding the two tabs of each longitudinal fin by an angle of 180 ° are performed while conveying the product through the pocket of a second packing wheel rotatably mounted about a second rotation axis and positioned directly after the straight-line packing conveyor.

Preferably, the method further comprises the step of folding the transverse fin by an angle of 90 ° with respect to the transverse edge of the bottom wall onto the front wall or rear wall.

Preferably, a modified atmosphere consisting mainly or entirely of at least one inert gas, preferably nitrogen, preferably enriched with sterilants and / or flavoring substances, is generated inside each sealed inner package, or a low pressure is applied to produce a vacuum or substantially vacuum sealed package internal.

A packaging assembly for forming a sealed inner package that surrounds the product, preferably comprising tobacco products, and having a front wall, a rear wall, two side walls, a bottom wall, and a top wall; the packaging assembly comprising: a first packaging device for folding a sheet of heat sealable material around the product to form a tubular wrapper having two open ends located on side walls each having two opposite side flaps extending from the product; a second packaging device for folding the two side flaps of the sheet of packing material at each open end of the tubular wrapper towards each other so as to overlap the two side flaps and form a longitudinal fin perpendicular to the underlying sidewall; and a first sealing element for welding the two superposed side flaps of each longitudinal fin to each other to stabilize the longitudinal fin; and a third packaging device is provided for folding each longitudinal fin through an angle of 90 ° onto the respective sidewall and for folding the two tabs of each longitudinal fin through an angle of 180 ° onto the longitudinal fin; wherein the first packaging apparatus comprises: a feed station, wherein the sheet of packaging material is U-folded about the product to form a first bottom flap that is flush with the front wall and extends from the bottom wall; and a second bottom flap that is flush with the rear wall and projects from the bottom wall; the first folding element for folding the two bottom flaps by an angle of 90 ° and in the same direction around the respective transverse edges of the bottom wall so as to overlap the two bottom flaps and form a transverse fin that is parallel to the bottom wall, has an inside edge located on the transverse edge of the bottom wall, and an outer edge located on the outside

PL 233 529 B1 and at a distance from the product; and a second sealing element for welding the two superposed bottom flaps to each other to stabilize the transverse fin; wherein the first packaging apparatus includes a first packaging wheel rotatably mounted about the first axis of rotation and supporting at least one product receiving pocket with a sheet of packaging material applied to it at a delivery station; wherein the second packaging apparatus comprises a rectilinear packaging conveyor for conveying the product wrapped in the tubular wrapper along the rectilinear packaging path; and at least two sealing grippers located on opposite sides of the rectilinear packaging conveyor, each designed to form and weld a respective longitudinal fin; and the inventive packaging assembly is characterized in that the third packaging device comprises a second packaging wheel rotatably mounted about the second rotation axis and supporting at least one pocket for receiving product from the second packaging device.

Preferably, the first packaging device comprises a second folding element for folding the transverse fin by an angle of 90 ° with respect to the transverse edge of the bottom wall onto the front wall or rear wall.

Preferably the first folding element is located in a fixed position close to the periphery of the first packing wheel and immediately downstream of the feeding station with respect to the direction of rotation of the first feeding wheel.

Preferably, the second sealing element is located close to the periphery of the first packing wheel and is movable radially with respect to the first packing wheel to press the transverse fin against the opposite face of the first packing wheel immediately in front of the pocket with respect to the rotation direction of the first packing wheel.

Preferably, the third packaging device comprises: two third folding members on opposite sides of the packaging wheel for folding the longitudinal fins through an angle of 90 °; two fourth folding members positioned on opposite sides of the second packing wheel behind the third folding members with respect to the direction of rotation of the second packing wheel for folding the longitudinal fin tabs through an angle of 180 °; and two third sealing elements located on opposite sides of the second packing wheel after the fourth folding elements with respect to the direction of rotation of the second packing wheel, for welding the tabs of the fins on the respective longitudinal fins.

Preferably the assembly comprises a chamber in which sealing of a sealed inner package is completed; wherein said chamber is connected to a supply device which supplies the chamber with packaging gas having a pressure above atmospheric pressure to maintain the chamber at a pressure above atmospheric pressure, or to a suction device for maintaining a pressure in the chamber below atmospheric pressure.

Figure 1 shows a perspective front view of a sealed inner packet of cigarettes, fig. 2 shows a perspective view of a group of cigarettes contained in the sealed inner packet of fig. 1, fig. 3 shows a perspective view of a stiffener, fig. which may be included in the sealed inner package of Fig. 1, Fig. 4 illustrates a plan view of the blank used to make the stiffener of Fig. 3, Fig. 5 illustrates a top view of the sheet of packaging material used to make the sealed inner package of Fig. 1, Figs. 6, 7 and 8 are three schematic side views showing the folding of the packing material sheet of Fig. 5 around the group of cigarettes of Fig. 2 to form the sealed inner package of Fig. 1, Figs. 9-12 are four perspective and schematic views showing the folding of the sheet of wrapping material of Fig. 5 around a group of paper of fig. 2 to form the sealed inner pack of fig. 1, fig. 13 is a schematic front view of a packing unit that produces the sealed inner pack of fig. 1 and is realized in accordance with the present invention, fig. 14 is a schematic view from on an enlarged scale of the first packing device of the packing group of Fig. 13, Fig. 15 is a schematic front view on an enlarged scale of the second packing device of the packing group of Fig. 13, Fig. 16 is a schematic front view, in enlarged scale. Fig. 13, Fig. 17 is a schematic front view on an enlarged scale of an alternative to the second packaging device of Fig. 15, Fig. 18 illustrates a front perspective view of another sealed inner package produced according to the method. In accordance with the present invention, Fig. 19 illustrates a perspective view of a cigarette pack that contained in a sealed package

18, Fig. 20 illustrates a top view of the sheet of packing material used to form the sealed inner package of Fig. 18, Fig. 21 illustrates a front perspective view of an alternative sealed inner package of Fig. 18, Fig. 22 illustrates a top view of the sheet of packing material used to form the sealed inner package of Fig. 21, Fig. 23 illustrates a front perspective view of another sealed inner package alternative of Fig. 18, and Fig. 24 illustrates a top view of the sheet of packaging material. used to form the sealed inner package of Fig. 23.

In Figure 1, number 1 designates a fully sealed inner packet of cigarettes, for example of the type described in US4300676A1.

As shown in Figure 2, the sealed inner package surrounds a group 2 of cigarettes having a parallelepiped shape and having a top wall 3 and a bottom wall 4 that are formed by the cigarette ends and are parallel and opposed to each other, a front wall 5 and a rear wall 6 which are they are formed by the cylindrical side walls of the cigarettes and are parallel and opposed to each other, and the two side walls 7 which are formed by the cylindrical side walls of the cigarettes and are parallel and opposed to each other. Between the front wall 5 and the rear wall 6 and between the side walls 7 of the group 2 of cigarettes, four longitudinal edges (i.e. parallel to the axis of symmetry of the cigarettes) are defined, between the front wall 5 and the rear wall 6 and between the top wall 3 and the bottom wall 4 of the group 2 of the cigarettes, four transverse longitudinal edges (i.e. perpendicular to the axis of symmetry of the cigarettes) are defined, and finally, between the top wall 3 and the bottom wall 4 and between the side walls 7 of the group 2 of cigarettes four shorter transverse edges (i.e. perpendicular to both the axis of symmetry cigarettes and to the long transverse edges).

As shown in Figure 1, the sealed inner package 1 has a cigarette removal opening 8 on the top and front (shown in Figure 4), which is delimited by a pre-weakened tear line, is closed by a reusable closure flap 9 and occupies part of the front wall of the sealed package. inner package 1 and a part of the top wall of the sealed inner package 1. According to a preferred embodiment, closure flap 9 has a graspable tab 10 and is attached to the sealed inner package 1 by non-drying multi-stick adhesive which is applied to the underside of closure flap 9 and is disposed. around the removal opening 8 to allow the closure flap 9 to be partially separated from the sealed inner package 1 several times and then reattached to the sealed inner package 1.

According to another, non-illustrated embodiment, the sealed inner package 1 does not have a removal opening 8 or an associated closure flap 9, but has a removable top which is separated from the rest of the sealed inner package 1 by a pre-weakened tear line for removal upon first opening of the sealed inner package. 1; in this embodiment, the sealed inner package 1 is preferably provided with a tear strip opening to facilitate tearing the sealed inner package 1 along a pre-weakened line.

The sealed inner package 1 is obtained by folding a sheet of wrapping material 11 (shown in figure 5) which is rectangular in shape, includes at least one layer of air-tight heat-sealable plastic, and is folded directly around a group of 2 cigarettes so as to contact it. them. After the packing material sheet 11 is folded around the group 2 of cigarettes to form the sealed inner package 1, the shape of the sealed inner package 1 is stabilized by welding the overlapping parts of the packing material sheet 11. It is important to note that the packing material sheet 11 can be multilayered and thus can have several different layers that are superimposed on one another (in this embodiment the packing material sheet 11 is generally opaque and can have a uniform metallic color on the outside. ) or alternatively it may be printed on the outside; the packing material sheet 11 may be single-ply (i.e. made of a single material), and in this embodiment the packing material sheet 11 is generally transparent.

Prior to the folding of the wrapping material sheet 11 around the group 2 of cigarettes, the wrapping material sheet 11 is pre-etched to define a removal opening 8; thereafter, a closure flap 9 with a rubberized bottom is applied to the sheet 11 of packaging material, i.e. provided on its underside with a re-stick adhesive, which

By means of the removal opening 8, the inner part of the packing material sheet 11 is permanently glued to the closure flap 9, and apart from the removal opening 8, it causes the packing material sheet 11 to stick to the closure flap 9, allowing multiple sticking.

As illustrated in Figures 3 and 4, the sealed inner package 1 comprises a stiffener 12 which is made of cardboard or rigid cardboard, is U-shaped and is placed inside the sealed inner package 1 in contact with the group 2 of cigarettes. In particular, the stiffener 12 has a front wall 13 of rectangular shape placed in contact with the front wall 5 of the group 2 of cigarettes, two side walls 14 which are connected to opposite sides of the front wall 13 and are placed in contact with the side walls 7 of the group 2 of cigarettes. , and a bottom wall 15 placed in contact with a bottom wall 4 of the group 2 of cigarettes. The front wall 13 has a window that is located at the top and is U-shaped and facilitates the removal of cigarettes from group 2 of cigarettes by leaving the top area of the front wall of group 2 of cigarettes exposed at the removal opening 8. Moreover, the stiffener 12 includes two side stabilizing tabs 16 which are connected to the side walls 14 and folded through 90 ° to the outer surface of bottom wall 15.

When the sealed inner package 1 is finished, i.e. at the end of forming the sealed inner package 1, the function of the stiffener 12 is to make the sealed inner package 1 more rigid and more dimensionally stable, so as to prevent the sealed inner package 1 from collapsing after removing some of the cigarettes contained in the sealed inner package. the inner packet 1, which would make it difficult to take out the remaining cigarettes, and in particular make it extremely difficult to open and later re-close the closure flap 9. When forming the sealed inner packet 1, the functions of the stiffener 12 are to provide adequate mechanical protection to the cigarettes and to simplify / improve handling of the group 2 breakdown of a group of 2 cigarettes). In other words, when operating the assembly formed by the group 2 of cigarettes and the stiffener 12, the stiffener 12 can be stabilized (i.e., prevent stiffener 12 from leaving the desired folded configuration) simply by mechanically preventing the side stabilizing tabs 16 from opening; in this way, the stiffener 12 acts as a box retaining the group 2 of cigarettes preventing the group 2 of cigarettes from disintegrating (obviously before the packing material sheet 11 is partially folded around the group of 2 cigarettes connected to the stiffener 12).

Figures 6-11 illustrate the sequence of folding sheet 11 of wrapping material around a group 2 of cigarettes to produce a sealed inner package 1.

As illustrated in figure 6, initially the packing material sheet 11 is folded in a "U" shape around the group 2 of cigarettes to form a first flap 17 that lies flush with the front wall 5 of the group 2 of cigarettes and projects from the bottom wall 4 of the group 2. 2 of the cigarettes, and a second bottom flap 18 that is flush with the back wall 6 of the group 2 of cigarettes and projects from the bottom wall 4 of the group 2 of cigarettes. It is important to note that the two bottom tabs 17 and 18 are not the same length, but the bottom tab 18 is longer (the length difference between the two bottom tabs 17 and 18 is equal to the thickness of the bottom wall 4 of group 2 of cigarettes). Then, and as shown in Figures 7 and 9, the two bottom flaps 17 and 18 are folded 90 ° and in the same direction around the respective transverse edges of the bottom wall 4 so as to overlap the two bottom flaps 17 and 18 and form a fin. a cross 19, which is parallel to the bottom wall 4 of the group 2 of cigarettes, has an inner edge 20 located at the edge of the transverse bottom wall 4 of the group 2 of cigarettes and an outer edge 21 located outside and at a predetermined distance from the group 2 of cigarettes. After the transverse fin 19 is formed, the two overlapping bottom flaps 17 and 18 are welded together to stabilize the transverse fin 19.

Finally, and as illustrated in Figures 8 and 10, the transverse fin 19 is folded at an angle of 90 ° with respect to the transverse edge of the bottom wall 4 of group 2 of cigarettes (i.e. around the inner edge 20 of the transverse fin 19) so as to rest the transverse fin 19 on this group. the very front wall 5 of the group 2 of cigarettes (i.e. rest the outer edge 21 of the transverse fin 19 against the front wall 5 of the group 2 of cigarettes).

In the embodiment illustrated in the accompanying figures, the transverse fin 19 is initially positioned close to the front wall 5 of the group 2 of cigarettes (as shown for example in figure 7) and then is folded against the front wall 5 of the group 2 of cigarettes (as shown for example in figure 8) ; according to one alternative and wholly equivalent embodiment not shown, the transverse fin 19 is initially positioned close to the rear wall 6 of group 2

It is folded against the rear wall 6 of the group 2 of cigarettes (in short, the front wall 5 is interchanged with the rear wall 6).

As illustrated in Figures 9 and 10, the formation of the transverse fin 19 gives the packing material sheet 11 the shape of a tubular wrapper that surrounds the inner group 2 of cigarettes and has two open ends 22 located on the side walls 7 of the group 2 of cigarettes (i.e. each open end 22 of the tubular group 2). the wrappers leave the corresponding sidewall 7 of the group 2 in view). Each open end 22 has two side flaps 23 which are opposed to each other and protrude from the group 2 of cigarettes (in particular from the corresponding side wall 7 of the group 2 of cigarettes).

As illustrated in figure 11, and after completing the formation and folding of the transverse fin 19, at each open end of the tubular wrapper, two respective side flaps 23 of the packing material sheet 11 are folded towards each other so as to overlap the two side flaps 23 and form a longitudinal fin 24. perpendicular to the underlying side wall 7 of the group of 2 cigarettes. In particular, each longitudinal fin 24 has an inner edge 25 positioned centrally of the side wall 7 of the group 2 of cigarettes (or placed in contact with the side wall 7 of the group 2 of cigarettes) and an outer edge 26 located outside and at a distance from the group 2 of cigarettes. After each fin 24 is formed, two superposed side flaps 23 of the fin 24 are welded together to stabilize the fin 24.

Then, and as illustrated in Figure 12, each longitudinal fin 24 is folded through a 90 ° angle so as to rest the longitudinal fin 24 against the corresponding sidewall 7 of the group 2 of cigarettes (i.e., support the outer edge 26 of each longitudinal fin 24 at one longitudinal edge of the wall). side 7 of group 2 cigarettes).

Each longitudinal fin 24 has two tabs 27 of substantially triangular shape situated on opposite sides of the respective side wall 7 of the group 2 of cigarettes and extending (or protruding) from the side wall 7.

Then, and as illustrated in figure 1, the two tabs 27 of each longitudinal fin 24 are folded through an angle of 180 ° onto the longitudinal fin 24 around the respective transverse edges of the respective side wall 7.

Finally, each tab 27 together with a portion of the underlying longitudinal fin 24 is welded to the underlying portion of the sheet 11 of packing material to stabilize the folded position of the tabs 27 and 24 of the longitudinal fins.

In figure 13, the number 28 indicates as a whole a packaging unit which is part of a packaging machine and is suitable for providing the sealed inner package 1 described above.

Packaging unit 28 includes a packaging device 29 for folding each sheet 11 of heat sealable wrapping material around a respective group of 2 cigarettes to form a tubular wrapper (shown in Figures 7-10) having two open ends 22 located on the side walls 7 of a group of 2 cigarettes, with each having two side flaps 23 which are opposite each other and protrude from the group of 2 cigarettes. In addition, the device 29 performs stabilization by welding each transverse fin 19 and then folds the transverse fin 19 at an angle of 90 ° against the front wall 5 of the respective group of 2 cigarettes.

Packaging unit 28 comprises a packaging device 30 for folding, at each open end 22 of the tubular wrapper, two respective side flaps 23 of the wrapping material sheet 11 towards each other to form a corresponding longitudinal fin 24 perpendicular to the underlying side wall 7 of a group of 2 cigarettes (as illustrated). in figure 11). In addition, the packaging device 30 performs stabilization by welding each longitudinal fin 24.

The packing unit 28 comprises a packing device 31 which performs the folding of the longitudinal fins 24 and the respective tabs 27 onto the side walls 7 of the respective group of 2 cigarettes. In particular, the packaging device 31 folds each longitudinal fin 24 by an angle of 90 ° so that the longitudinal fin 24 rests on the respective side wall 7 of the respective group 2 of cigarettes (as shown in figure 12) and folds the two tabs 27 of each longitudinal fin 24 by an angle of 180 ° onto the longitudinal fin 24 (as shown in figure 1). Finally, the packaging machine 31 performs welding of the tabs 27 of each longitudinal fin 24 to stabilize the folded position of the tabs 27 and the longitudinal fins 24.

As illustrated in Figure 14, the packaging machine 29 comprises a packaging wheel 32 rotatably mounted about a horizontal axis of rotation (perpendicular to the plane of figure 14) so as to rotate stepwise.

PL 233 529 B1 (i.e., in intermittent motion). The packing wheel 32 includes a plurality of pockets 33 each adapted to receive and contain a respective group of 2 cigarettes connected to the stiffener 10 and to the sheet 11 of packing material.

The packaging device 29 comprises a feed station 34 in which a group of 2 cigarettes connected to a stiffener 10 and to a sheet 11 of packing material are fed into the respective pocket 33; at the feed station 34 and consequently at the pocket inlet 33, each packing material sheet 11 is folded in a "U" shape around a group of 2 cigarettes (as shown in Figure 6) to form two bottom flaps 17 and 18 (shown in Figure 6). The packing station 29 comprises a folding element 35 for folding the two bottom flaps 17 and 18 at an angle of 90 ° and in the same direction to form a corresponding transverse fin 19 (as shown in figure 7). The folding element 35 is positioned in a fixed position close to the periphery of packaging wheel 32 and immediately downstream of the feeding station 34 in relation to the direction of rotation of the packaging wheel 32.

It is important to note that at station 34 where the group 2 of cigarettes 2 connected to the stiffener 12 is inserted together with the packing material sheet 11 into the corresponding pocket 35 of the packing wheel 32, the group 2 of cigarettes does not disintegrate (i.e. does not disintegrate). 2) loses its ordered configuration illustrated in figure 2) due to the locating action of the stiffener 12. As previously mentioned, when operating the whole formed by the group 2 of cigarettes and the stiffener 12, it is possible to stabilize the stiffener 12 (i.e., prevent the stiffener 12 from leaving its desired folded configuration) simply by mechanically preventing opening the side stabilizing tabs 16; in this way, the stiffener 12 acts as a box retaining the group 2 of cigarettes preventing the group 2 of cigarettes from disintegrating (obviously before the packing material sheet 11 is partially folded around the group of 2 cigarettes connected to the stiffener 12).

The packaging device 29 comprises two sealing elements 36, each of which is located close to the periphery of the packaging wheel 32 downstream of the feed station 34 in relation to the direction of rotation of the packaging wheel 32 and is suitable for welding the transverse fin 19. According to a preferred embodiment, each sealing element 36 is radially movable. against the packing wheel 32 to press the respective transverse fin 19 against the opposite surface of the packing wheel 32 located immediately in front of the pocket with respect to the rotation direction of the packing wheel 32 (as shown in figure 14).

The packaging machine 29 includes a folding element 37 which is placed on a transfer station 38 where each tubular wrapper (i.e., each group of 2 cigarettes is connected to a stiffener and wrapped in a sheet 14 of packing material) exits the corresponding pocket of the packing wheel 29. the folding 37 folds each transverse fin 19 by an angle of 90 ° so as to rest the transverse fin 19 against the front wall 5 of the group 2 of cigarettes when the corresponding tubular wrapper comes out of the pocket of the packing wheel 29. The folding element 37 is located in a fixed position close to the periphery of the packing wheel 29 located immediately in front of pocket 33, stopped and waiting in the transfer station 38, with respect to the direction of rotation of the packing wheel 29.

The packaging apparatus 29 includes a transfer wheel 39 which is positioned adjacent to the packaging wheel 32 rotatably mounted about a horizontal axis of rotation (parallel to the rotation axis of the packaging wheel 32) so as to rotate in steps (or intermittently). The wheel 39 includes a plurality of transfer pockets 40 each of which are suitable for receiving and accommodating a respective group of 2 cigarettes connected to the stiffener 10. At entry station 41, each pocket 40 of the transfer wheel 39 receives a group of 2 cigarettes connected to the stiffener 10; then, at a further inlet station 42, located downstream of the inlet station 41 with respect to the direction of rotation of the transfer wheel 39, a sheet 11 of packing material is laid on the periphery of the transfer wheel 39, which rests on the periphery of the transfer wheel 39 on both sides of the respective pocket 40 (i.e. the sheet 11 of the packing material covers the inlet / outlet of pocket 40). At the delivery station 34, a pusher 43 connected to transfer wheel 39 pushes the respective group 2 of cigarettes connected to stiffener 10 from the pocket 40 of the transfer wheel 39 into the pocket 33 of the packing wheel 32; during this movement the group 2 of cigarettes picks up the sheet 11 of wrapping material disposed between the two pockets 40 and 33, taking it with it to the pocket 33 of the wrapping wheel 32.

As shown in Figure 15, the apparatus 30 includes a straight-line packaging conveyor 44 that feeds each tubular wrapper (or each group of 2 cigarettes connected to a stiffener 10 and wrapped with a sheet 14 of packaging material) along a linear packaging path.

Furthermore, the packaging apparatus 30 includes two twin folding stations 45 arranged in series (i.e., one behind the other) along a linear packaging path; each post consisting of 45

The welding grippers 46 are disposed on opposite sides of the rectilinear packing conveyor 44, each suitable for forming and welding a respective longitudinal fin 24. Each sealing gripper 46 folds, on the open side 22 of each tubular wrapper, two side flaps 23 of the sheet 11 of the packing material towards each other so as to overlap the two side flaps 23 and form a longitudinal fin 24 (illustrated in figure 11) and simultaneously heat (e.g. by means of electric thermoresistors) the two superposed side flaps 3 to thereby weld (stabilize) longitudinal fin 24. The packing conveyor 44 runs intermittently with alternating movement and stop phases, and the sealing grippers 46 of each folding station 45 press together the two side flaps 23 of each tubular wrapper during the stop phase (i.e. when tubular). the wrapper is stopped and waits in front of the sealing grippers 46).

The rectilinear packaging conveyor 44 includes a static plane 47 (i.e., no movement) on which the tubular wrappers containing groups of 2 cigarettes are fed (i.e., moved) under the pressure of an assembly of pushers 48 which reciprocate along a rectilinear packaging path. The followers 48 are supported by a single support body 49 that is moved by an arm 50 connected to an actuator (not shown); support body 49 cyclically travels a loop path having an active stroke (or discharge stroke) in which, starting from the home position, pushers 48 of carrying body 49 push the back of the tubular wraps to feed along a straight packing path, and a passive stroke (or reverse stroke). wherein the tappets 48 of the carrying body 49 return to the starting position without touching the tubular wraps (i.e., disengaging from the tubular wraps).

At the end of the packaging conveyor 44 there is a transfer station 50 on which the sealed inner package 1 (not yet fully completed but already provided with fins 19 and 24 as shown in figure 11) is transferred from the packaging conveyor 44 to the packaging apparatus 31.

As illustrated in figure 16, packaging apparatus 31 comprises a packaging wheel 51 rotatably mounted about a horizontal axis of rotation (perpendicular to the plane of figure 16 and parallel to the axis of rotation of packaging wheel 32) so as to rotate stepwise (i.e., intermittently). Packaging wheel 51 includes a plurality of pockets 52 each adapted to receive and enclose a respective sealed inner package 1 (i.e. a group of 2 cigarettes attached to a stiffener and wrapped in a sheet 11 of packaging material as shown in figure 11) fed through the packaging conveyor 44 of the packaging machine 30 at the conveying station 50. The packaging device 31 comprises two fixed folding elements 53 (i.e. fixed folding "screws") positioned on opposite sides of the packing wheel 51 downstream of the transfer station 50 with respect to the direction of rotation of the packing wheel 51 and folding the longitudinal fins 24 of each sealed inner package. 1 by 90 ° (as shown in figure 12).

The packaging device 31 includes two fixed folding elements 54 (i.e., fixed folding "screws") positioned on opposite sides of the packing wheel 51 behind the folding elements 53 with respect to the direction of rotation of the packing wheel 51 and folding the tabs 27 of the longitudinal fins 24 through an angle of 180 ° (as shown in Figure 1). Finally, the packaging device 31 comprises two sealing elements 55 located on opposite sides of the packaging wheel 51 downstream of the folding elements 54 in relation to the direction of rotation of the packaging wheel 51 and seals each tab 27, together with a portion of the underlying longitudinal fin 24, with the underlying portion of the material sheet 11 to be packaging to stabilize the folded position of the tabs 27 and the longitudinal fins 24.

In the embodiment illustrated in Figure 17, packaging apparatus 30 comprises a chamber 56 that houses part of a rectilinear packaging conveyor 44; in particular, chamber 56 houses folding stations 45 at which the sealing (i.e., airtight closure) of the sealed inner package 1 is completed. A supply device is connected to chamber 56 which supplies the main chamber 56 with packaging gas having a higher pressure than the pressure. atmospheric pressure to keep chamber 56 under positive pressure relative to atmospheric pressure. In this way, a modified atmosphere consisting of gases (packaging gas) different (wholly or at least partially) from normal terrestrial atmospheric gases is provided inside each sealed inner package 1. By way of example, the packaging gas consists essentially of an inert gas (usually nitrogen) to which sterilants and / or flavorings may be added. In particular, the flavorings may include menthol flavor, tobacco flavor, coffee flavor, anise flavor. According to an alternative embodiment, a suction device is connected to the chamber 56, which holds the chamber 56 underneath

Low pressure relative to atmospheric pressure. In this way, a more rarefied atmosphere is provided inside each sealed inner package 1 compared to the normal earth atmosphere. Further design details regarding the chamber 56 can be found in, for example, patent application B02013A000294.

In other words, a modified atmosphere consisting mainly or entirely of at least one inert gas, preferably nitrogen, preferably enriched with sterilants and / or flavoring substances, or a sufficiently low pressure to create a vacuum or substantially a vacuum inside, is generated inside each sealed inner package 1. sealed inner packaging 1.

As an alternative to using chamber 56, so-called oxygen scavengers ("deoxidizers") can be used, i.e. materials capable of spontaneously oxidizing and thus trapping molecular oxygen contained in the sealed inner package 1 (e.g. oxygen scavengers most commonly used in the food industry are iron base). In other words, an oxygen absorbing material is inserted into the inside of the sealed inner package 1 which, after sealing the sealed inner package 1, slowly (i.e. after a time of a few minutes) absorbs at least some of the molecular oxygen inside the sealed inner package. The oxygen absorbing material may be contained in a specially provided liner which is inserted into the inside of the sealed inner package 1 or it may be supported by the stiffener 12 and / or the inner surface of the sheet 11 of the packaging material (in this case the oxygen absorbing material is applied by treatment surface, even nanotechnology, of the stiffener 12 and / or the inner surface of the sheet 11 of the packaging material).

In the embodiment illustrated in figures 1-17, a sealed inner package

And surrounds a group 2 of cigarettes which is placed in direct contact with a sealed inner package 1. In the embodiment shown in Figures 18-24, the sealed inner package 1 surrounds a cigarette pack 57 which is of the rigid type (shown in Figure 19) or of the soft type; in particular, the cigarette packet 57 comprises an inner package (not shown) that surrounds the group of 2 cigarettes, and an outer package surrounding the inner package. In this embodiment, the sealed inner package 1 is a top wrap that wraps the cigarette packet 57 to protect it. The packing material sheet 11 used to produce the sealed inner package 1 is preferably (but not necessarily) made of an airtight, heat-sealable and transparent plastic (e.g. polyethylene or polypropylene).

As illustrated in Figures 18 and 20, the packing material sheet 11, and thus the sealed inner package 1, is provided with a tear strip 58 which is used to open and remove the sealed inner package (1) when the cigarette pack 57 is first opened; i.e. the tear strip 58 is adapted to tear the sheet 11 of the packing material (i.e. the sealed inner package 1 formed from the folded sheet)

II of the packing material) to allow later removal of at least a portion of the sealed inner package 1. The tear strip 58 is applied (typically welded, but also optionally stuck) onto the packing material sheet 11 so as to adhere to the packing material sheet 11; by pulling one end 59 of the initial tear strip 58, the packing material sheet 11 (i.e., sealed inner package 1 formed from the folded packing material sheet 11) tears along the tear strip 58 (which is mechanically stronger and more resistant than sheet material 11) for packing), allowing the sheet 11 of packing material to be easily and quickly caused to break in a controlled manner.

According to the preferred embodiment illustrated in Figures 18 and 20, the front end 59 of the tear strip 58 extends freely from one edge of the sheet 11 of the packing material, and the rear end 60 of the tear strip 58 is disposed at a distance from the opposite edge of the sheet 11 of the packing material. . As a result, the front end 59 of the tear strip 58 is located at the outer edge 21 of the fin 19 and extends freely from the outer edge 21 of the transverse fin 19. In use, the user grips the front end 59 of the tear strip 58 at the outer edge 21 of the transverse fin 19, and then it begins to pull the tear strip 58 away from the sheet 11 of packing material (i.e., a sealed inner package 1 formed from the folded sheet 11 of packing material). According to a preferred embodiment illustrated in figures 18 and 20, at the front end 59 of the tear strip 58 and in line with the front end

In the tear strip 58, two through cuts 61 are formed in the packing material sheet 11 which cut the sealed inner package sheet 11 from side to side and serve to facilitate the initial tearing of the packing material sheet 11 near the front end 59 tear strap 58. According to another and wholly equivalent embodiment, the through cuts 61 are not previously formed in the packing material sheet 11, but are formed during the sealing of the transverse fin 19 (i.e. at least one of the sealing elements 36 that seals the transverse fin 19 has small blades forming through cuts 61 at the outer edge 21 of the transverse fin 19).

In the embodiment illustrated in Figures 18 and 20, the tear strip 58 is positioned longitudinally (so that the tear strip 58 cuts perpendicularly the transverse fin 19); in the alternative shown in Figures 21 and 22, the tear strip 58 is arranged transversely (so that the tear strip 58 crosses the longitudinal fins 24 perpendicularly) and the packing material sheet 11 (shown in Figure 22) is formed by two separate parts which initially they are separate and are superimposed upon each other as the sheet 11 of packing material is folded.

Also in the alternatively shown in Figures 23 and 24 the tear strip 58 is positioned transversely, but the folding method of the packing material sheet 11 (which consequently has a different shape) is inverted such that two longitudinal fins 24 are provided on the top wall and bottom wall. packs of 57 cigarettes.

It is important to note that the packaging machine may only comprise a packaging unit 28 (in this case, each sealed inner package 1 described above is a finished product and is immediately salable); alternatively, the packaging machine may further comprise a packaging unit of known type for wrapping around each sealed inner package 1, a respective outer shell that surrounds the sealed inner package 1 and may be formed of a sheet of packaging material folded around the sealed inner package 1 having the shape of a cup (soft packet). cigarettes) or may be obtained from a rigid box with a hinge lid formed by folding a rigid blank around a sealed inner package 1 (rigid cigarette pack).

The sealed inner package 1 and the packing unit 28 for producing the sealed inner package 1 described above have numerous advantages.

First, the sealed inner package 1 described above is tighter, i.e. it guarantees an optimal seal against the outside environment; said result is obtained in that the closure of the sealed inner package 1 is guaranteed by three fins 19 or 24 ensuring the maximum possible tightness. In particular, during welding, each fin 19 or 24 allows a very high mechanical pressure to be applied to compress the overlapping edges of the packing material sheet 11 forming the fin 19 or 24 together, since said mechanical pressure does not put any strain on the group 2 of cigarettes or the packet. 57 cigarettes. Moreover, with each fin 19 or 24, the overlapping of the portion of the sheet 11 of packing material is always done by contacting only a portion of the inner surface of the packing material sheet 11 (i.e. without using the outer surface of the packing material sheet 11), thereby makes the welding stronger and stable.

The sealed inner package 1 described above can also be easily obtained by using a packaging machine with a simple structure; as a result, the sealed inner package 1 described above can be manufactured quickly while maintaining high manufacturing quality.

Moreover, the packaging unit 28 described above for producing the sealed inner package 1 has, on the one hand, a simple and low-cost structure, and, on the other hand, allows both high-quality production and high production capacity to be achieved.

Claims (9)

Patent claims A packaging method for producing a sealed inner package (1) that surrounds a product (2; 57), preferably comprising tobacco products, and having a front wall (5), a rear wall (6), two side walls (7), a bottom wall (4) and a top wall (3); the packing method includes the steps: Folding the sheet (11) of heat sealable packaging material around the product (2; 57) to form a tubular wrapper having two open ends (22) located on side walls (7) each having two opposite each other side flaps (23) protruding from the product (2; 57); folding the two side flaps (23) of the wrapping material sheet (11) at each open end (22) of the tubular wrapper towards each other so as to overlap the two side flaps (23) and form a longitudinal fin (24) perpendicular to the underlying wall side (7); welding the two superposed side flaps (23) of each longitudinal fin (24) to each other to stabilize the longitudinal fin (24); folding each longitudinal fin (24) through an angle of 90 ° to the respective side wall (7); and folding the two tabs (27) of each longitudinal fin (24) through an angle of 180 ° onto the longitudinal fin (24) and about the respective transverse edges of the respective side wall (7); wherein the step of folding the sheet (11) of packaging material to form the tubular wrapper further comprises the steps of: folding the sheet (11) of wrapping material in a "U" shape around the product (2; 57) to form a first bottom flap (17) flush with the front wall (5) and protruding from the bottom wall (4). and a second bottom flap (18) that is flush with the rear wall (6) and projects from the bottom wall (4); folding the two bottom flaps (17, 18) by an angle of 90 ° and in the same direction around the respective transverse edges of the bottom wall (4) so as to overlap the two bottom flaps (17, 18) and form a transverse fin (19) which it is parallel to the bottom wall (4), has an inner edge (20) situated at the transverse edge of the bottom wall (4) and an outer edge (21) situated outside and at a distance from the product (2; 57); and welding the two superposed lower flaps (17, 18) to each other to stabilize the transverse fin (19); wherein the step of folding the sheet (11) of packaging material to form the tubular wrap is performed while conveying the product (2; 57) through a pocket (33) on the first packaging wheel (32) rotatably mounted about the first rotation axis; and wherein the step of folding the side flaps (23) of the sheet (11) of packaging material to form the longitudinal fins (24) and the step of welding the superposed side flaps (23) of each longitudinal fin (24) together are performed during the transfer of the product ( 2; 57) by a rectilinear packaging conveyor (44) located downstream of the first packaging wheel (32); the packing method being characterized in that the step of folding each longitudinal fin (24) by an angle of 90 ° and the step of folding the two tabs (27) of each longitudinal fin (24) by an angle of 180 ° are performed during the conveyance of the product (2; 57) by a pocket (52) of a second packaging wheel (51) rotatably mounted about a second axis of rotation and located immediately downstream of the straight packaging conveyor (44). The packaging method according to claim 1, further comprising the step of folding the transverse fin (19) at an angle of 90 ° to the transverse edge of the bottom wall (4) onto the front wall (5) or rear wall (6). 3. Packaging method according to claim 1 or 2, wherein a modified atmosphere is generated inside each sealed inner package (1) consisting mainly or entirely of at least one inert gas, preferably nitrogen, preferably enriched with sterilants and / or flavoring substances, or low pressure is applied to form a vacuum or substantially vacuum sealed inner package (1). 4. A packaging unit (28) for producing a sealed inner package (1) that surrounds the product (2; 57), preferably containing tobacco products, and having a front wall (5), a rear wall (6), two side walls (7), a bottom wall (4) and a top wall (3); the packing unit (28) comprising: a first packaging device (29) for folding a sheet (11) of heat-sealable packaging material around the product (2; 57) to form a tubular wrapper having two open ends (22) located on the side walls (7) each having two facing side flaps (23) protruding from the product (2; 57); A second packaging device (30) for folding the two side flaps of the wrapping material sheet (11) at each open end (22) of the tubular wrapper towards each other so as to overlap the two side flaps (23) and form a longitudinal fin ( 24) perpendicular to the underlying sidewall (7); and a first sealing element for welding the two superposed side flaps (23) of each longitudinal fin (24) to each other to stabilize the longitudinal fin (24); and a third packaging device (31) is provided for folding each longitudinal fin (24) through an angle of 90 ° on the respective side wall (7) and for folding the two tabs (27) of each longitudinal fin (24) through an angle of 180 ° on the longitudinal fin ( 24); wherein the first packaging machine (29) comprises: a feed station (34) where a sheet (11) of packaging material is folded in a "U" shape around the product (2; 57) to form a first bottom flap (17) that is flush with the front wall (5) and it projects from the bottom wall (4); and a second bottom flap (18) that is flush with the rear wall (6) and projects from the bottom wall (4); a first folding element (35) for folding the two bottom flaps (17, 18) at an angle of 90 ° and in the same direction around respective transverse edges of the bottom wall (4) so as to overlap the two bottom flaps (17, 18) and form a transverse fin (19) that is parallel to the bottom wall (4), has an inner edge (20) located on the transverse edge of the bottom wall (4), and an outer edge (21) located outside and at a distance from the product (2) ; 57); and a second sealing element (36) for welding the two overlapping bottom flaps (17, 18) to each other to stabilize the transverse fin (19); wherein the first packaging apparatus (29) includes a first packaging wheel (32) rotatably mounted about the first axis of rotation and supporting at least one product receiving pocket (33) (2; 57) with a sheet (11) of packaging material applied therein, at the delivery station (34); wherein the second packaging apparatus (30) comprises a rectilinear packaging conveyor (44) for conveying the wrapped product (2; 57) along the rectilinear packaging path; and at least two sealing grippers (46) disposed on opposite sides of the rectilinear packaging conveyor (44), each designed to form and weld a respective longitudinal fin (24); and the packaging unit (28) is characterized in that the third packaging device (31) comprises a second packaging wheel (51) rotatably mounted about the second axis of rotation and supporting at least one pocket (52) for receiving a product (2; 57) from the second. a packaging device (30). 5. Packaging group (28) according to claim 4, wherein the first packaging device (29) comprises a second folding element (37) for folding the transverse fin (19) at an angle of 90 ° to the transverse edge of the bottom wall (4) onto the front wall (5). ) or the rear wall (6). A packaging group (28) according to claim 4 or 5, wherein the first folding element (35) is located in a fixed position close to the periphery of the first packing wheel (32) and immediately downstream of the feeding station (34) with respect to the direction of rotation of the first feeding wheel (32). ). A packaging unit (28) according to claim 4, 5 or 6, wherein the second sealing element (36) is positioned close to the periphery of the first packaging wheel (32) and is movable radially with respect to the first packaging wheel (32) to compress the transverse fin ( 19) to the opposite face of the first packing wheel (32) located immediately in front of the pocket (33) with respect to the rotation direction of the first packing wheel (32). 8. A packaging group (28) according to one of the claims 4 to 7, wherein the third packaging device (31) comprises: two folding elements (53) on opposite sides of the packing wheel (51) for folding the longitudinal fins (24) by an angle of 90 °; two fourth folding elements (54) positioned on opposite sides of the second packing wheel (51) behind the third folding elements (53) with respect to the rotation direction of the second packing wheel (51), for folding the tabs (27) of the longitudinal fins (24) by 180 ° ; and PL 233 529 Β1 two-thirds sealing elements (55) positioned on opposite sides of the second packing wheel (51) behind the fourth folding elements (54) with respect to the rotation direction of the second packing wheel (51), for welding [tabs (27)] of the longitudinal fins ( 24) on the longitudinal fins (24). 9. Packaging group (28) according to one of claims 4 to 8, characterized in that it comprises a chamber (56) in which the sealing of the sealed inner package (11) is completed; wherein said chamber (56) is connected to a supply device that supplies the chamber (56) with packing gas having a pressure higher than atmospheric pressure to maintain the chamber (56) at a pressure above atmospheric pressure, or to a suction device for maintaining pressure atmospheric pressure of the chamber (56) at a pressure below atmospheric pressure.