EP4663560A1

EP4663560A1 - Wrapping unit and method to produce two sealed wraps, together, by simultaneously folding two wrapping sheets around two corresponding groups of smoking articles

Info

Publication number: EP4663560A1
Application number: EP25179718.9A
Authority: EP
Inventors: Quintino MARRONE; Terence TONELLI
Original assignee: GD SpA
Current assignee: GD SpA
Priority date: 2024-06-05
Filing date: 2025-05-29
Publication date: 2025-12-17

Abstract

A wrapping unit (10) and a method to produce two sealed wraps (3) together, by simultaneously folding two wrapping sheets (8) around two corresponding groups (5) of smoking articles. The following are provided: a first wrapping conveyor (11) configured to advance the two side-by-side groups (5) of smoking articles coupled to the two wrapping sheets (8) along the first wrapping path (P1) and at a first distance (D1) from one another; two first folding devices (22), each of which is arranged along the first wrapping path (P1) and is configured to fold, in a tube-like manner, a wrapping sheet (8) around a corresponding group (5) of smoking articles; two first sealing devices (23), each of which is arranged along the first wrapping path (P1) and is configured to perform a heat seal, which stabilizes the tubular shape of a wrapping sheet (8) around a corresponding group (5) of smoking articles; a second wrapping conveyor (12) arranged downstream of the first wrapping conveyor (11) and configured to advance the two side-by-side groups (5) of smoking articles coupled to the two wrapping sheets (8) along a second wrapping path (P2) and at a second distance (D2) from one another, greater than the first distance (D1); two second folding devices (24), each of which is arranged along the second wrapping path (P2) and is configured to complete the folding of a wrapping sheet (8) around a corresponding group (5) of smoking articles so as to form a corresponding sealed wrap (3); and two second sealing devices (27), each of which is arranged along the second wrapping path (P2) and is configured to perform heat seals, which stabilize the shape of a corresponding sealed wrap (3).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority from Italian patent application No. 102024000012874 filed on June 5, 2024 , the entire disclosure of which is incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a wrapping unit and a method to produce two sealed wraps together, containing two corresponding groups of smoking articles, in particular by simultaneously folding two wrapping sheets around the two corresponding groups of smoking articles.

PRIOR ART

Patent application WO2023180862A1 describes a wrapping unit to produce two sealed wraps together, by simultaneously folding two wrapping sheets around two corresponding groups of smoking articles. The wrapping unit comprises: a wrapping conveyor that is capable of advancing the two side-by-side groups of smoking articles and coupled to the two wrapping sheets along a straight wrapping path; two folding devices, each of which is coupled to the wrapping conveyor and is arranged along the wrapping path to fold two opposite ends of a wrapping sheet around a corresponding group of smoking articles; and two sealing devices, each of which is coupled to the wrapping conveyor and is arranged along the wrapping path downstream of the respective folding device to perform a seal on both sides of a wrapping sheet folded around a corresponding group of smoking articles. Each sealing device comprises an outer sealing head arranged outside the wrapping conveyor, an inner sealing head arranged at the centre of the wrapping conveyor, and an actuator configured to move the two sealing heads between: a working position in which the two sealing heads are at a first mutual distance determining a compression of the corresponding group of smoking articles; an advancing position in which the two sealing heads are at a second mutual distance that is greater than the first mutual distance and allows the corresponding group of smoking articles to advance along the wrapping path; and a rest position in which the two sealing heads are at a third mutual distance that is greater than the second mutual distance. In particular, each actuator is configured to move the two sealing heads between the working position and the advancing position along a first direction perpendicular to the wrapping path, and is configured to move at least the inner sealing head to and from the rest position along a second direction perpendicular to both the first direction and the wrapping path. However, the construction of the inner sealing heads is relatively complex (especially when the sealed wraps are small) due to the limited space available for the inner sealing heads and it is necessary to equip the inner seal heads with movement in two different and mutually perpendicular directions.
Patent application EP3653518A1 describes the feeding of two wrapping sheets in a wrapping machine, wherein an initial double-width wrapping sheet is supplied and subsequently split into two halves by applying a force that tears it along a centrally located pre-weakened separation line.

DESCRIPTION OF THE INVENTION

The object of the present invention is to provide a wrapping unit and a method to produce two sealed wraps together by simultaneously folding two wrapping sheets around two corresponding groups of smoking articles, which wrapping unit and method are simple to implement, allow an operation at high production rate (measured as sealed wraps produced per unit of time), and permit rapid format changeover operations.
According to the present invention, a wrapping unit and a method are provided to produce two sealed wraps together by simultaneously folding two wrapping sheets around two corresponding groups of smoking articles, as claimed in the appended claims.
The claims describe preferred embodiments of this invention, forming an integral part of this description.

BRIEF DESCRIPTION OF THE DRAWINGS

This invention will now be described with reference to the accompanying drawings, which illustrate a non-limiting embodiment thereof, wherein:

Figure 1 is a front perspective view of a "twin" type rigid cigarette pack in a closed configuration, i.e., containing two side-by-side sealed wraps;
Figure 2 is a rear perspective view of the cigarette pack of Figure 1 in a closed configuration;
Figure 3 is a front perspective view of the cigarette pack of Figure 1 in an open configuration;
Figure 4 is a front perspective view of a single sealed wrap contained in the cigarette pack of Figure 1;
Figure 5 is a perspective view of a group of cigarettes coupled with a reinforcing element and contained in the sealed wrap of Figure 4;
Figure 6 is a plan view of a wrapping sheet used to form the sealed wrap of Figure 4;
Figure 7 is a schematic and perspective view showing the paths followed by the components of the sealed wrap of Figure 4 in a wrapping unit made in accordance with the present invention;
Figure 8 is a schematic and side view of some components of the wrapping unit of Figure 7; and
Figure 9 is a schematic and plan view of other components of the wrapping unit of Figure 7.

PREFERRED EMBODIMENTS OF THE INVENTION

Figures 1, 2 and 3 illustrate as a whole a "twin" rigid cigarette pack, indicated by reference numeral 1. The cigarette pack 1 comprises a container 2 consisting of cardboard or stiff paperboard and shaped like a cup and a pair of sealed wraps 3 (one of which is better illustrated in Figure 4) housed side by side inside the container 2.
The container 2 has an open top end and is provided with a lid 4, which is shaped like a cup and hinged to the container 2 along a hinge (illustrated in Figure 2) to rotate, in relation to the container 2, between an open position (illustrated in Figure 3) and a closed position (illustrated in Figures 1 and 2) of the open top end.
Each sealed wrap 3 (better illustrated in Figure 4) encloses a group 5 of cigarettes having a parallelepiped shape (illustrated in Figure 5) and has, at the top and front, an extraction opening 6 for the cigarettes, which is defined by a tearable pre-weakened line, is closed by a resealable closing label 7, and extends across a portion of a front wall of the sealed wrap 3 and a portion of a top wall of the sealed wrap 3.
According to a not illustrated different embodiment, the sealed wrap 3 lacks the extraction opening 6 and the corresponding closing label 7, and has a removable top portion, which is separated from the rest of the sealed wrap 3 by a tearable pre-weakened line to be removed by tearing upon the first opening of the sealed wrap 3; in this embodiment, the sealed wrap 3 is preferably provided with a tearable opening tape to facilitate the rupture of the sealed wrap 3 along the pre-weakened line.
The sealed wrap 3 is formed by folding a wrapping sheet 8 (illustrated in Figure 6), which has a rectangular shape, comprises at least one layer of heat-sealable and air-tight plastic material, and is folded directly around the group 5 of cigarettes so as to be in direct contact with the cigarettes themselves. Once the wrapping sheet 8 has been folded around the group 5 of cigarettes to form the sealed wrap 3, the shape of the sealed wrap 3 itself is stabilized by forming a transverse heat seal on the overlapping portions of the wrapping sheet 8.
The sealed wrap 3 may comprise a reinforcing element 9 (better illustrated in Figure 5), which is made of cardboard or stiff paperboard, is U-shaped, and is placed inside the sealed wrap 3 in contact with the group 5 of cigarettes.
The formation of the sealed wrap 3 involves initially forming the group 5 of cigarettes and then folding the reinforcing element 9 around the group 5 of cigarettes; subsequently, the wrapping sheet 8 is folded around the group 5 of cigarettes coupled with the reinforcing element 9. The methods for folding the wrapping sheet 8 around the group 5 of cigarettes coupled with the reinforcing element 9 are known and are, for example, described in patent application WO2023180862A1 ; alternatively, the two open lateral edges of the wrapping sheet 5 may be closed by means of two longitudinal sealing fins instead of a so-called "soap wrap".
In particular, and as illustrated in Figure 7, the wrapping sheet is U-folded around the group 5 of cigarettes in such a way that the U-folded wrapping sheet 8 has two ends protruding from the group 5 of cigarettes; the two ends are then folded toward each other to give a tubular shape to the wrapping sheet 8 and, thus, the overlapping portions of the ends are heat-sealed together to stabilize the tubular shape of the wrapping sheet 8 and form a sealing fin. Finally, the overlapping and heat-sealed ends (i.e., the sealing fins) are folded against a bottom wall of the sealed wrap 3 or a front wall of the sealed wrap 3.
A wrapping machine adapted to produce the above-described cigarette pack 1 typically operates with an intermittent motion (i.e., a motion involving a cyclical alternation of motion phases and rest phases) and comprises a forming unit where the groups 5 of cigarettes are formed in succession, a wrapping unit 10 (schematically illustrated in Figure 7) in which a respective wrapping sheet 8 is wrapped around each group 5 of cigarettes to form a sealed wrap 3, and a wrapping unit in which a blank is wrapped around each pair of sealed wraps 3 (i.e., arranged side by side) to form the container 2 provided with the lid 4.
As shown in Figure 7, the wrapping unit 10 (which produces two sealed wraps 3 together, containing two corresponding group 5 of cigarettes) comprises wrapping conveyors which are adapted to advance the two side-by-side groups 5 of cigarettes along wrapping paths. In particular, each wrapping conveyor supports a plurality of pairs of side-by-side pockets, each shaped to receive and accommodate a corresponding group 5 of cigarettes; in this way, at each advancement step, each wrapping conveyor advances two side-by-side pockets (transversely, i.e., perpendicularly to the wrapping path) and therefore two side-by-side groups 5 of cigarettes contained in the respective side-by-side pockets.
As shown in Figure 8, the wrapping unit 10 comprises a wrapping conveyor 11 receiving pairs of side-by-side groups 5 of cigarettes at a transfer station S1 and is adapted to advance the pairs of side-by-side groups 5 of cigarettes along with the corresponding wrapping sheets 8 along a wrapping path P1 to (begin to) fold each wrapping sheet 8 around the corresponding group 5 of cigarettes. In particular, the wrapping path P1 extends from the transfer station S1, where the wrapping conveyor 11 receives two groups 5 of cigarettes at a time, crosses a feeding station S2 where each pair of side-by-side groups 5 of cigarettes is coupled with a corresponding pair of side-by-side wrapping sheets 8, and ends at a transfer station S3 where the forming sealed wrap pairs 3 (i.e., each consisting of a wrapping sheet 8 only partially folded around a corresponding group 5 of cigarettes) leave the wrapping conveyor 11.
In particular, along the wrapping path P1 (i.e., while being advanced by the wrapping conveyor 11), each wrapping sheet 8 is initially U-folded and then folded in a tube-like manner around a corresponding group 5 of cigarettes, and the tubular wrap (with two open lateral ends) so formed is stabilized by means of a transverse seal.
As shown in Figure 9, the wrapping unit 10 comprises a wrapping conveyor 12 that is located downstream of the wrapping conveyor 11 (i.e., it receives the pairs of side-by-side groups 5 of cigarettes coupled to the wrapping sheets 8 coming from the wrapping conveyor 11) and is adapted to advance the pairs of side-by-side groups 5 of cigarettes coupled to the wrapping sheets 8 along a straight and horizontal wrapping path P2 to (complete to) fold each wrapping sheet 8 around the corresponding group 5 of cigarettes. Specifically, the wrapping path P2 extends from a transfer station S4, where the wrapping conveyor 12 receives two groups 5 of cigarettes coupled to wrapping sheets 8 at a time, and ends at a transfer station S5, where the complete sealed wrap pairs 3 (i.e., each consisting of a fully folded wrapping sheet 8 around a corresponding group 5 of cigarettes) leave the wrapping conveyor 12.
In particular, along the wrapping path P2 (i.e., while being advanced by the wrapping conveyor 12), each tubular wrap 3 is laterally closed by lateral folds, which are then stabilized by two longitudinal seals, thereby completing (ending) the formation of the tubular wrap 3 (as illustrated in Figure 7).
According to what is shown in Figures 8 and 9, the wrapping unit 10 comprises a transport wheel 13 (horizontally arranged) which is interposed between the wrapping conveyor 11 and the wrapping conveyor 12, rotatably mounted around a vertical rotation axis 14 (perpendicular to the wrapping path P2), and supports four pairs of pockets 15, each of them adapted for containing a group 5 of cigarettes coupled with a wrapping sheet 8 (therefore, a pair of side-by-side pockets 15 supports a pair of side-by-side groups 5 of cigarettes and coupled with their respective wrapping sheets 8). By rotating about the rotation axis 14, the wrapping wheel 13 advances each pair of side-by-side pockets 15 along a circular transport path P3 between the transfer station S3, where the pair of side-by-side pockets 15 receives a pair of side-by-side groups 5 of cigarettes coupled to wrapping sheets 8 from the wrapping conveyor 11, and the transfer station S4 in which the pair of side-by-side pockets 15 delivers the pair of side-by-side groups 5 of cigarettes coupled with the wrapping sheets 8 to the wrapping conveyor 12.
According to what is shown in Figure 8, the wrapping conveyor 11 comprises a wrapping wheel 16 (vertically arranged), which is rotatably mounted about a horizontal rotation axis 17 (parallel to the wrapping path P2 and perpendicular to the rotation axis 14), and supports a plurality of pairs of pockets 18, each of which is suitable for containing a group 5 of cigarettes coupled to a wrapping sheet 8 (therefore, a pair of side-by-side pockets 18 placed axially supports a pair of side-by-side groups 5 of cigarettes coupled to their respective wrapping sheets 8). By rotating about the rotation axis 17, the wrapping wheel 16 advances each pair of side-by-side pockets 18 along a circular transport path P1 between the transfer station S1, where the pair of side-by-side pockets 18 receives a pair of side-by-side groups 5 of cigarettes from the forming conveyor 37, through the feeding station S2 in which the pair of side-by-side pockets 18 receives a pair of side-by-side wrapping sheets 8 which are arranged outside the pair of side-by-side pockets 18, and a transfer station S6 in which the pair of side-by-side pockets 18 delivers the pair of side-by-side groups 5 of cigarettes and coupled to the sheets wrapping 8.
According to what is illustrated in Figure 8, the wrapping conveyor 11 comprises a wrapping wheel 19 (vertically arranged) which is arranged immediately downstream of the wrapping wheel 16 and immediately upstream of the wrapping wheel 13, is rotatably mounted around a horizontal rotation axis 20 (parallel to the rotation axis 17 and perpendicular to the rotation axis 14) and supports a plurality of pairs of pockets 21, each of which is capable of containing a group 5 of cigarettes coupled to a wrapping sheet 8 (thus, a pair of axially side-by-side pockets 21 supports a pair of side-by-side groups 5 of cigarettes coupled to respective wrapping sheets 8). By rotating about the rotation axis 20, the wrapping wheel 19 advances each pair of side-by-side pockets 21 along the circular wrapping path P1 between the transfer station S6, where the pair of side-by-side pockets 21 receives a pair of side-by-side groups 5 of cigarettes coupled to wrapping sheets 8 from the wrapping wheel 16, and the transfer station S4 in which the pair of side-by-side pockets 21 delivers the pair of side-by-side groups 5 of cigarettes coupled with the wrapping sheets 8 to the wrapping wheel 13.
In other words, at the feeding station S3 two side-by-side wrapping sheets 8 are placed on the periphery of the wrapping wheel 16 at a respective pair of side-by-side pockets 18 and move with the respective pair of side-by-side pockets 18 to the transfer station S6; at the transfer station S6, the two side-by-side groups 5 of cigarettes on leaving the side-by-side pair of pockets 18 of the wrapping wheel 16 and entering the respective pair of side-by-side pockets 21 of the wrapping wheel 19, drag with them the two side-by-side wrapping sheets 8 which, on entering the pockets 21, are U-folded around the side-by-side groups 5 of cigarettes.
As illustrated in Figure 8, the wrapping unit 10 comprises two folding devices 22, each of which is coupled to the wrapping wheel 19 and is configured to fold, in a tube-like manner, a wrapping sheet 8 around the corresponding group 5 of cigarettes contained in a respective pocket 21. Each wrapping sheet 8 is U-folded around the corresponding group 5 of cigarettes when the group 5 of cigarettes enters (together with the wrapping sheet 8) the respective pocket 21 in the transfer station S6; in addition, each folding device 22 performs the tubular folding of each wrapping sheet 8 around the corresponding group 5 of cigarettes. The wrapping wheel 19 advances along the wrapping path P1 a succession of pairs of side-by-side groups 5 of cigarettes coupled to the wrapping sheets 8 (by means of corresponding pairs of side-by-side pockets 21) and, thus, the two folding devices 22 are placed side-by-side to perform the folding of two wrapping sheets 8 around two side-by-side groups 5 of cigarettes together and at the same time.
In addition, the wrapping unit 10 comprises two sealing devices 23, each of which is coupled to the wrapping wheel 19 and is configured to perform a transversal seal on a wrapping sheet 8, folded in a tube-like manner, around the corresponding group 5 of cigarettes contained in a respective pocket 21. According to a preferred embodiment, each sealing device 23 comprises three different sealing heads arranged in succession around the wrapping wheel 19 (i.e., along the wrapping path P1) in such a way that the transverse welding on each wrapping sheet 8, folded in a tube-like manner, is performed in three distinct and successive steps. The wrapping wheel 19 advances along the wrapping path P1 a succession of pairs of side-by-side groups 5 of cigarettes coupled to the wrapping sheets 8 and, thus, the two sealing devices 23 are placed side-by-side to perform the sealing of two wrapping sheets 8 around two side-by-side groups 5 of cigarettes together and at the same time.
As illustrated in Figure 9, the wrapping unit 10 comprises two folding devices 24, each of which is coupled to the wrapping conveyor 12 and is configured to fold a wrapping sheet 8 around the corresponding group 5 of articles by completing the formation of the sealed wrapping 3, i.e. by closing the two open ends of the tube-folded wrapping sheet 8. The wrapping conveyor 12 advances along the wrapping path P2 a succession of pairs of side-by-side groups 5 of cigarettes coupled to the wrapping sheets 8 and, thus, the two folding devices 24 are placed side-by-side to perform the folding of two wrapping sheets 8 around two side-by-side groups 5 of cigarettes together and at the same time.
In particular, each folding device 24 comprises two fixed folding blades 25 and 26 (i.e., folding profiles with no moving parts) arranged along the wrapping path P2 (i.e., along the wrapping conveyor 12). In particular, a total of four fixed folding blades 25 and 26 are provided, each of which folds one side end of a corresponding tube-folded wrapping sheet 8: the wrapping conveyor 12 advances along the wrapping path P2 a succession of pairs of side-by-side groups 5 of cigarettes coupled to the tube-folded wrapping sheets 8, so that for each group 5 of cigarettes, two fixed folding blades 25 and 26 are required, arranged at the two opposite ends of the group 5 of cigarettes. Accordingly, two fixed folding blades 25 are arranged in the centre of the wrapping conveyor 12 (one fixed folding blade 25 operating with the group 5 of cigarettes placed on the right and the other fixed folding blade 25 operating with the group 5 of cigarettes placed on the left) and two fixed folding blades 26 at the sides of the wrapping conveyor 12 (one fixed folding blade 26 operating with the group 5 of cigarettes placed on the right and the other fixed folding blade 26 operating with the group 5 of cigarettes placed on the left).
As illustrated in Figure 22, the wrapping unit 10 comprises two sealing devices 27, each of which is coupled to the wrapping conveyor 12 and is configured to perform longitudinal seals on a wrapping sheet 8 folded around the group 5 of cigarettes completing the formation of the corresponding sealed wrapping 3. Each sealing device 27 is coupled to the wrapping conveyor 12 and is arranged along the wrapping path P2 downstream of the respective folding device 24 to perform a two-sided sealing of a wrapping sheet 8 folded around a corresponding group 5 of cigarettes. According to a preferred embodiment, each sealing device 27 comprises a plurality of outer sealing heads 28 arranged outside the wrapping conveyor 12 and a plurality of inner sealing heads 29 arranged in the centre of the wrapping conveyor 12 (i.e., in the central free area between two side-by-side groups 5 of cigarettes). Accordingly, two inner sealing heads 29 are arranged in the centre of the wrapping conveyor 12 (one inner sealing head 29 operating with the group 5 of cigarettes placed on the right and the other inner sealing head 29 operating with the group 5 of cigarettes placed on the left) and two outer sealing head 28 at the sides of the wrapping conveyor 12 (one outer sealing head 28 operating with the group 5 of cigarettes placed on the right and the other outer sealing head 28 operating with the group 5 of cigarettes placed on the left). Each sealing device 27 comprises several sealing heads 28 and 29 arranged in succession along the wrapping conveyor 12 (i.e., along the wrapping path P2) in such a way that the longitudinal seals on each wrapping sheet 8 are performed in several distinct and successive stages.
The wrapping conveyor 12 advances along the wrapping path P2 a succession of pairs of side-by-side groups 5 of cigarettes coupled to the wrapping sheets 8 and, thus, the two sealing devices 27 are placed side by side to perform the sealing of two wrapping sheets 8 around two side-by-side groups 5 of cigarettes together and at the same time.
As mentioned earlier, along the wrapping path P1 (and, thus, at the wrapping conveyor 11) there is a feeding station S2 where pairs of side-by-side wrapping sheets 8 are arranged on the periphery of the wrapping wheel 16 at a pair of side-by-side pockets 18 (containing two respective side-by-side groups 5 of cigarettes). In the feeding station S2, two side-by-side wrapping sheets 8 may either already be completely separated (i.e., there is no residual joining point between the two side-by-side wrapping sheets 8, which are therefore completely independent of one another) or the two side-by-side wrapping sheets 8 may be joined by one or more tearable joining points which will be torn off later to permanently separate the two side-by-side wrapping sheets 8 (as described in the patent application EP3653518A1 ).
As illustrated in Figure 8, in the transfer station S1 a pusher 30 and a follower 31 are arranged, which transfer two side-by-side groups 5 of cigarettes to a pair of side-by-side pockets 18 of the wrapping wheel 16.
As illustrated in Figure 8, in the transfer station S6 a pusher 32 and a follower 33 are arranged, which transfer two side-by-side groups 5 of cigarettes coupled to two wrapping sheets 8 from a pair of side-by-side pockets 18 of the wrapping wheel 16 to a pair of side-by-side pockets 21 of the wrapping wheel 19.
As illustrated in Figure 8, in the transfer station S3 a pusher 34 and a follower 35 are arranged, which transfer two side-by-side groups 5 of cigarettes coupled with two tube-folded wrapping sheets 8 from a pair of side-by-side pockets 21 on the wrapping wheel 19 to a pair of side-by-side pockets 15 of the wrapping wheel 13.
As illustrated in Figure 9, in the transfer station S4 a pusher 36 is arranged, which transfer two side-by-side groups 5 of cigarettes coupled to two tube-folded wrapping sheets 8 from a pair of side-by-side pockets 15 of the wrapping wheel 13 to the wrapping conveyor 39.
As illustrated in Figure 9, the wrapping conveyor 11 is configured to advance two side-by-side groups 5 of cigarettes at a distance D1 from one another along the wrapping path P1, whereas the wrapping conveyor 12 is configured to advance two side-by-side groups 5 of cigarettes at a distance D2 from one another greater than the distance D1 along the wrapping path P2. That is, along the wrapping path P2 two side-by-side groups 5 of cigarettes are further apart than along the wrapping path P1.
Preferably, the transport wheel 13 is configured to increase the mutual distance between two side-by-side groups 5 of cigarettes provided with the tube-folded wrapping sheets 8 between the transfer station S3 and the transfer station S4. That is, the pockets 15 are mounted in a movable manner on the transport wheel 13 in such a way that each pair of side-by-side pockets 15 can cyclically increase and decrease their mutual distance. Thus, the two pockets 15 of each pair of side-by-side pockets 15 are arranged at distance D1 from one another at the transfer station S3, and are arranged at distance D2 from one another greater than distance D1 at the transfer station S4.
The transport wheel 13 comprises an actuator device 37 configured to space apart the two pockets 15 of each pair of side-by-side pockets 15 between the transfer station S3 and the transfer station S4. Preferably, the actuator device 37 uses a fixed cam to generate the translational movement of the pockets 15 with respect to the transport wheel 13; specifically, two side-by-side pockets 15 are mounted on two slides sliding on the same linear guide carried by the transport wheel 13 and a lever operated by the cam pushes the two slides along the linear guide. According to one possible embodiment, in each pair of side-by-side pockets 15, both pockets 15 are mounted in a movable manner to move always in opposite directions (i.e., to move away from one another or to move closer to one another); alternatively, in each pair of side-by-side pockets 15, one pocket 15 is fixedly mounted on the transport wheel 13 and the other pocket 15 is mounted in a movable manner on the transport wheel 13 and is, therefore, the only one moving to increase and decrease the mutual distance between the two pockets 15.
According to a preferred embodiment, when two side-by-side groups 5 of cigarettes are placed at mutual distance D1, the two corresponding wrapping sheets 8 are in mutual contact, i.e., they touch one another without overlapping. Therefore, distance D1 is the minimum distance possible to allow the tube-like folding of both side-by-side wrapping sheets 8 without overlapping the wrapping sheets 8. Furthermore, the distance D1 is the distance that corresponds exactly to obtaining the two wrapping sheets 8 by means of a central cut of a double-width wrapping sheet. Consequently, the distance D1 is particularly convenient as it simplifies the feeding of the wrapping sheets 8 and allows the tube-like folding of both side-by-side wrapping sheets 8. The distance D2 is greater than the distance D1 and allows the space between two side-by-side groups 5 of cigarettes to be increased to the benefit of the inner sealing heads 29, which must occupy precisely the space existing between two side-by-side groups 5 of cigarettes.
In the embodiment illustrated in the attached figures, the distance between two side-by-side groups 5 of cigarettes is increased from the distance D1 to the distance D2 by means of a purely horizontal translation that keeps the two groups 5 of cigarettes mutually coplanar; in an alternative embodiment, the distance between the two side-by-side groups 5 of cigarettes is increased from the distance D1 to the distance D2 by means of an at least partially vertical translation which makes the two groups 5 of cigarettes not coplanar (i.e., which arranges the two groups 5 of cigarettes in different and offset planes). In other words, in the embodiment illustrated in the attached figures, two side-by-side groups 5 of cigarettes are always coplanar (vertically aligned) with one another, whereas, according to an alternative embodiment, downstream of the transport wheel 13 two side-by-side groups 5 of cigarettes are not coplanar with one another and are therefore vertically offset. The embodiments described herein may be combined with one another without departing from the scope of protection of the present invention.
The wrapping unit 10 described above has many advantages.
Firstly, the wrapping unit 10 described above allows for the production of sealed wraps 1 with a high production quality (i.e., presenting accurate and square wrapping sheet 5 folds and strong and sealing wrapping sheet 5 seals) even while operating at a high production rate (i.e., with a high number of sealed wraps 3 produced per unit of time).
In addition, the wrapping unit 10 described above has high accessibility to all its components, and thanks to this feature, format changeover operations (i.e., adaptation operations to change the characteristics of the sealed packages 1 to be produced) can be carried out quickly.
Finally, the wrapping unit 10 described above is relatively simple to implement thanks to the fact that a sufficiently large space is available for the inner sealing heads 25, i.e. it is not necessary to resort to a major miniaturization of the movements and controls of the inner welding heads 25. This result is achieved by increasing the distance between two side-by-side groups 5 of cigarettes from the value D1 lower than the higher value D2 before feeding the two side-by-side groups 5 of cigarettes to the wrapping conveyor 12. The embodiment illustrated in the attached figures refers to the manufacture of a cigarette pack, but this invention is also applicable, without substantial modification, to the production of any other type of pack of smoking articles (e.g., a cigar pack, a pack for electronic cigarettes of the liquid vaporisation type, a pack of new generation cigarettes without tobacco combustion, etc.).

LIST OF REFERENCE NUMBERS IN THE FIGURES

1: cigarette pack
2: container
3: sealed wrapping
4: lid
5: group of cigarettes
6: dispensing opening
7: closing label
8: wrapping sheet
9: reinforcing element
10: wrapping unit
11: wrapping conveyor
12: wrapping conveyor
13: transport wheel
14: rotation axis
15: pocket
16: wrapping wheel
17: rotation axis
18: pocket
19: wrapping wheel
20: rotation axis
21: pocket
22: folding devices
23: sealing devices
24: folding devices
25: folding blades
26: folding blades
27: sealing devices
28: outer sealing heads
29: inner sealing heads
30: pusher
31: follower
32: pusher
33: follower
34: pusher
35: follower
36: pusher
37: actuator device
S1: transfer station
S2: feeding station
S3: transfer station
S4: transfer station
S5: transfer station
S6: transfer station
P1: wrapping path
P2: wrapping path
P3: transport path

Claims

A wrapping unit (10) to produce two sealed wraps (3) together, by simultaneously folding two wrapping sheets (8) around two corresponding groups (5) of smoking articles; the wrapping unit (10) comprises:
a first wrapping conveyor (11) configured to advance the two side-by-side groups (5) of smoking articles coupled to the two wrapping sheets (8) along a first wrapping path (P1);

two first folding devices (22), each of which is arranged along the first wrapping path (P1) and is configured to fold, in a tube-like manner, a wrapping sheet (8) around a corresponding group (5) of smoking articles;

two first sealing devices (23), each of which is arranged along the first wrapping path (P1) and is configured to perform a heat seal, which stabilizes the tubular shape of a wrapping sheet (8) around a corresponding group (5) of smoking articles;

a second wrapping conveyor (12) arranged downstream of the first wrapping conveyor (11) and configured to advance the two side-by-side groups (5) of smoking articles coupled to the two wrapping sheets (8) along a second wrapping path (P2);

two second folding devices (24), each of which is arranged along the second wrapping path (P2) and is configured to complete the folding of a wrapping sheet (8) around a corresponding group (5) of smoking articles so as to form a corresponding sealed wrap (3); and

two second sealing devices (27), each of which is arranged along the second wrapping path (P2) and is configured to perform heat seals, which stabilize the shape of a corresponding sealed wrap (3);

the wrapping unit (10) is characterized in that:

the first wrapping conveyor (11) is configured to advance the two groups (5) of smoking articles at a first distance (D1) from one another along the first wrapping path (P1); and

the second wrapping conveyor (12) is configured to advance the two groups (5) of smoking articles at a second distance (D2) from one another, greater than the first distance (D1), along the second wrapping path (P2).
The wrapping unit (10) according to claim 1 and comprising a transport conveyor (13), which is interposed between the first wrapping conveyor (11) and the second wrapping conveyor (12) and is configured to receive the two groups (5) of smoking articles provided with the wrapping sheets (8) folded in a tube-like manner from the first wrapping conveyor (11) in a first transfer station (S3) and to release the two groups (5) of smoking articles provided with the wrapping sheets (8) folded in a tube-like manner to the second wrapping conveyor (12) in a second transfer station (S4).
The wrapping unit (10) according to claim 2, wherein the transport conveyor (13) is configured to increase the mutual distance between the two groups (5) of smoking articles provided with the wrapping sheets (8) folded in a tube-like manner between the first transfer station (S3) and the second transfer station (S4).
The wrapping unit (10) according to claim 3, wherein:
the transport conveyor (13) comprises a pair of pockets (15), each designed to accommodate a corresponding group (5) of smoking articles provided with a wrapping sheet (8) folded in a tube-like manner; and

the two pockets (15) are mounted on the transport conveyor (13) in a movable manner,

are arranged at the first distance (D1) from one another in the first transfer station (S3) and are arranged at the second distance (D2) from one another, which is greater than the first distance (D1), in the second transfer station (S4).
The wrapping unit (10) according to claim 4, wherein the transport conveyor (13) comprises an actuator device (37) configured to space the two pockets (15) apart from one another between the first transfer station (S3) and the second transfer station (S4).
The wrapping unit (10) according to claim 5, wherein the actuator device (37) uses a fixed cam.
The wrapping unit (10) according to one of the claims 2 to 6, wherein the transport conveyor (13) is mounted so as to rotate around a rotation axis (14).
The wrapping unit (10) according to one of the claims 1 to 7, wherein the first wrapping path (P1) is perpendicular to the second wrapping path (P2).
The wrapping unit (10) according to one of the claims 1 to 8, wherein each second folding device (24) comprises two fixed folding blades (25, 26), which are arranged along the second wrapping path (P2) and each fold a side end of a corresponding wrapping sheet (8) folded in a tube-like manner.
The wrapping unit (10) according to one of the claims 1 to 9, wherein each second sealing device (27) comprises at least one outer sealing head (28) arranged outside the second wrapping conveyor (12) and at least one inner sealing head (29) arranged in the centre of the second wrapping conveyor (12).
The wrapping unit (10) according to one of the claims 1 to 10, wherein, when the two groups (5) of smoking articles are arranged at the first distance (D1) from one another, the two wrapping sheets (8) are in mutual contact.
The wrapping unit (10) according to one of the claims 1 to 11, wherein the distance between the two side-by-side groups (5) of smoking articles is increased by means of a translation, which keeps the two groups (5) of smoking articles coplanar.
The wrapping unit (10) according to one of the claims 1 to 11, wherein the distance between the two side-by-side groups (5) of smoking articles is increased by means of a translation, which makes the two groups (5) of smoking articles mutually non coplanar.
A wrapping method to produce two sealed wraps (3) together by simultaneously folding two wrapping sheets (8) around two corresponding groups (5) of smoking articles; the wrapping method comprises the steps of:
advancing, by means of a first wrapping conveyor (11), the two side-by-side groups (5) of smoking articles coupled to the two wrapping sheets (8) along a first wrapping path (P1);

folding in a tube-like manner, by means of two first folding devices (22) arranged along the first wrapping path (P1), each wrapping sheet (8) around a corresponding group (5) of smoking articles;

heat sealing, by means of two first sealing devices (23) arranged along the first wrapping path (P1), to stabilize the tubular shape of each wrapping sheet (8) around a corresponding group (5) of smoking articles;

advancing, by means of a second wrapping conveyor (12) arranged downstream of the first wrapping conveyor (11), the two side-by-side groups (5) of smoking articles coupled to the two wrapping sheets (8) along a second wrapping path (P2);

completing, by means of two second folding devices (24) arranged along the second wrapping path (P2), the folding of each wrapping sheet (8) around a corresponding group (5) of smoking articles so as to form a corresponding sealed wrap (3); and

heat sealing, by means of two second sealing devices (27) arranged along the second wrapping path (P2), to stabilize the shape of each sealed wrap (3);

the wrapping method is characterized in that it comprises the steps of:

advancing the two groups (5) of smoking articles at a first distance (D1) from one another along the first wrapping path (P1); and

advancing the two groups (5) of smoking articles at a second distance (D2) from one another, greater than the first distance (D1), along the second wrapping path (P2).