This application claims priority from Italian Patent Application No. 102017000055670 filed on May 23, 2017, the disclosure of which is incorporated by reference. TECHNICAL FIELD

The present invention relates to a packing machine for manufacturing packets of smoking articles each containing two distinct groups of smoking articles. The present invention finds advantageous application for a cigarette packing machine which manufactures packets of cigarettes known as "twin" each containing two distinct groups of cigarettes, wrapped in respective separate wraps, to which the following disclosure will make explicit reference without thereby losing generality.

PRIOR ART

A packet of cigarettes commercially known as "twin" has been known for several years and comprises a rigid outer container which internally houses two groups of identical cigarettes (namely "twin" from which the trade name of the packet of cigarettes originated) , which are arranged beside one another and wrapped in corresponding sheets of wrapping material. Patent application WO2017064659A1 (corresponding to the Italian patent application 102015000062561) describes a packing machine for producing a "twin" packet of cigarettes comprising: a forming unit wherein the groups of cigarettes are formed in succession, a first wrapping unit wherein, around each group of smoking articles, a sheet of wrapping material is folded to form a corresponding inner wrap, a coupling unit wherein the inner wraps are coupled two by two so as to form the content of the packets of cigarettes, and a second wrapping unit where a collar and a blank are folded around each pair of inner wraps so as to form an outer container.

The coupling unit comprises a coupling drum which supports a plurality of support bodies, each of which supports a pair of housing heads arranged beside one another. Each support body advances through a first transfer station where the two housing heads successively receive two corresponding inner wraps and through a second transfer station where both the housing heads simultaneously release the two inner wraps side by side with the second wrapping unit. In the first transfer station the two housing heads of the same support body are arranged further from one another to receive the two inner wraps in succession, and subsequently the two housing heads move closer to one another to arrange the two inner wraps next to each other so that in the second transfer station the two coupled inner wraps are transferred together.

The second wrapping unit comprises a wrapping drum which supports a plurality of wrapping heads which advance through a feeding station where each wrapping head receives a collar, through the second transfer station where each wrapping head receives two coupled inner wraps, and through a third transfer station where each wrapping head releases the pair of inner wraps together with the collar. The packing machine described in the Italian patent application 102015000062561 allows the production of high quality packets of cigarettes, namely packets of cigarettes wherein the positioning and folding of the various wrapping materials are very precise; however, said packing machine is not able to operate, while guaranteeing a high quality for the packets of cigarettes, at a high hourly productivity (namely the number of packets produced in the time unit)

DESCRIPTION OF THE INVENTION

The object of the present invention is to provide a packing machine for manufacturing packets of smoking articles, each containing two separate groups of smoking articles, which packing machine is able to achieve a high hourly productivity without, simultaneously, compromising the final quality of the packets.

According to the present invention, a packing machine is provided for manufacturing packets of smoking articles each containing two distinct groups of smoking articles, as claimed in the appended claims.

The claims describe preferred embodiments of the present invention thus forming an integral part of the present disclosure . BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to the accompanying drawings, which illustrate an example of non-limiting embodiment, wherein:

- Figure 1 is a front perspective view and in a closed configuration of a "twin" packet of cigarettes;

- Figure 2 is a front perspective view and in an open configuration of the "twin" packet of cigarettes of Figure 1;

- Figure 3 is a perspective view of an inner wrap contained in the "twin" packet of cigarettes of Figure 1;

- Figure 4 is a perspective view of a group of cigarettes contained in the inner wrap of Figure 3;

- Figure 5 is a schematic front view of part of a packing machine which produces the "twin" packet of cigarettes of Figure 1 and is manufactured according to the present invention;

Figure 6 is an enlarged-scale view of a detail of a coupling drum of the packing machine of Figure 5; and

- Figure 7 is an enlarged-scale view of a detail of a wrapping drum of the packing machine of Figure 5. PREFERRED EMBODIMENTS OF THE INVENTION

In Figures 1 and 2, number 1 denotes as a whole, a "twin" rigid packet of cigarettes comprising a rigid outer container 2 provided with a hinged lid and a pair of inner wraps 3, which are arranged beside one another and are housed inside the outer container 2. Each inner wrap 3 (better illustrated in Figure 3) encloses a parallelepiped shaped group of cigarettes 4 (illustrated in Figure 4) and has a removable tear-off portion at the top, which is removed so as to allow access to the cigarettes.

Each inner wrap 3 is made by folding, in known manner, a rectangular shaped sheet 5 of wrapping material (illustrated schematically in Figure 5), around the group 4 of cigarettes. Each inner wrap 3 may be devoid of stabilization (namely the corresponding sheet 5 of wrapping material does not have connections between the overlapping parts and therefore must always be firmly held to prevent the folds from unfolding due to elastic return) , it can be stabilized by using glue, or it can be stabilized by heat-sealing (in this last case the inner wrap 3 is normally hermetically sealed) . According to an alternative embodiment, the inner wraps 3 are absent and each group 4 of cigarettes is directly housed inside the outer container 2 without the interposition of the corresponding inner wrap 3.

Each rigid outer container 2 provided with the hinged lid is made by folding an oblong rectangular shaped blank 6 around a pair of side by side inner wraps 3 in a known manner. According to a possible embodiment illustrated in Figure 2, the rigid outer container 2 comprises two collars 7, each of which is folded in a U-shape so as to embrace a corresponding inner wrap 3 and is connected (by gluing) to the outer container 2 so as to partially protrude outside an open upper end of the outer container 2 and to engage a corresponding inner surface of the lid when the lid is arranged in said closed position. According to an alternative embodiment not illustrated, the rigid outer container 2 comprises a single collar 7, which is folded in a U-shape to embrace both the inner wraps 3.

In Figure 5, number 8 denotes as a whole a packing machine (only partially illustrated in Figure 5) which is adapted to manufacture the packet of cigarettes 1 described above. The packing machine 8 comprises a forming unit 9 (only schematically illustrated in Figure 5) where the groups 4 of cigarettes are formed in succession, a wrapping unit 10 where the sheet 5 of wrapping material is folded around each group 4 of cigarettes so as to form the corresponding inner wrap 3, a coupling unit 11 where two by two the inner wraps 3 (namely the groups 4 of cigarettes contained in the inner wraps 3) are coupled so as to form the content of the packets 1 of cigarettes, and a wrapping unit 12 where around each pair of inner wraps 3 (namely to each pair of groups 4 of cigarettes contained in the inner wraps 3) the collar 7 and the blank 6 are folded so as to form the corresponding outer container 2.

According to what is illustrated in Figure 5, the wrapping unit 10 comprises a wrapping drum 13 which is mounted in a rotating manner with a continuous movement (namely with a motion devoid of stopping phases wherein the various moving parts move at a constant speed) around a rotation axis 14 horizontal and perpendicular to the plane of Figure 5 and supports a plurality (in particular twelve) wrapping heads 15 (only one of which is illustrated in Figure 5 for simplicity) . The rotation of the wrapping drum 13 around the rotation axis 14 brings each wrapping head 15 through a feeding station SI where the wrapping head 15 receives a sheet 5 of wrapping material, a transfer station S2 where the wrapping head 15 receives a group 4 of cigarettes from the forming unit 9, and a transfer station S3 where the wrapping head 15 releases an inner wrap 3 to the coupling unit 11. Between the feeding station SI and the transfer station S3, each sheet 5 of wrapping material is folded around a group 4 of cigarettes to form a corresponding inner wrap 3.

According to what is illustrated in Figure 5, the coupling unit 11 comprises a coupling drum 16 which is mounted in a rotating manner with a continuous movement around a rotation axis 17 parallel to the rotation axis 14 and supports a plurality (in particular six) of support bodies 18 (only one of which is illustrated in Figure 5 for simplicity) . Each support body 18 is mounted in a rotating manner on the coupling drum 16 and supports a pair of housing heads 19, which are in turn rotary on the support body 18 and are arranged beside one another; each housing head 19 supports a corresponding coupling pocket which is adapted to house (contain) an inner wrap 3 (namely a group 4 of cigarettes contained in an inner wrap 3) . The rotation of the coupling drum 16 around the rotation axis 17 brings each support body 18 through the transfer station S3 where the two corresponding housing heads 19 receive in succession two respective inner wraps 3 and through a transfer station S4 where both the housing heads 19 simultaneously release the two side by side inner wraps 3; in the transfer station S3 the two housing heads 19 of the same support body 18 are arranged (relatively) further from one another in order to receive successively the two inner wraps 3 and subsequently the two housing heads 19, move closer to one another to arrange the two inner wraps 3 next to each other (side by side) so that in the transfer station S4 the two coupled inner wraps 3 are transferred together (namely leaving the two housing heads 19 of the same support body 18 together) .

According to what is illustrated in Figure 5, the wrapping unit 12 comprises a wrapping drum 20 which is mounted in a rotating manner with a continuous movement around a rotation axis 21 parallel to the rotation axis 17 and supports a plurality (in particular six) of wrapping heads 22 (only one of which is illustrated in Figure 5 for simplicity) . The rotation of the wrapping drum 20 around the rotation axis 21 brings each wrapping head 22 through a feeding station S5 where the wrapping head 22 receives the collar 7 (or, alternatively, a pair of collars 7), through the transfer station S4 where the wrapping head 22 receives two coupled inner wraps 3, and through a transfer station S6 where the wrapping head 22 releases the pair of inner wraps 3 together with the collar 7.

The wrapping unit 12 comprises a feeding drum 23 which is mounted in a rotating manner with a continuous movement around a rotation axis 24 parallel to the rotation axis 21 and supports a plurality (in particular three) of feeding heads 25 (only one of which is illustrated in Figure 5 for simplicity) . The rotation of the feeding drum 23 around the rotation axis 24 brings each feeding head 25 through the feeding station S5 where the feeding head 25 releases the collar 7 to a wrapping head 22 of the wrapping drum 20.

According to what is illustrated in Figure 5, the wrapping unit 12 comprises a wrapping drum 26 which is mounted in a rotating manner with a continuous movement around a rotation axis 27 parallel to the rotation axis 21 and supports a plurality (in particular six) of wrapping heads 28 (only one of which is illustrated in Figure 5 for simplicity) . The rotation of the wrapping drum 26 around the rotation axis 27 brings each wrapping head 28 through a feeding station S7 where the wrapping head 28 receives the blank 6, through the transfer station S6 where the wrapping head 28 receives two coupled inner wraps 3 together with the collar 7, and through a transfer station S8 where the wrapping head 28 releases the packet 1 of cigarettes to a drying conveyor 29 which carries the packets 1 of cigarettes towards the outlet of the packing machine 1. Between the feeding station S7 and the transfer station S8, each blank 6 is folded around two inner wraps 3 coupled together with the collar 7 so as to form a corresponding outer container 2.

According to a preferred embodiment, the "even" wrapping heads 15 of the wrapping drum 13 operate with a law of motion different from the "odd" wrapping heads 15 of the wrapping drum 13: in other words, to release two inner wraps 3 (which will then be coupled to enter the same packet 1 of cigarettes) to the two housing heads 19 of the same support body 18 the "even" wrapping head 15, which releases the first inner wrap 3 to a housing head 19 operates with a law of motion different from the "odd" wrapping head 15 which releases the second inner wrap 3 to the other housing head 19; obviously, the law of motion of the "even" wrapping heads 15 of the wrapping drum 13 differs from the law of motion of the "odd" wrapping heads 15 of the wrapping drum 13 only at the transfer station S3 where the inner wraps 3 pass from the wrapping heads 15 of the wrapping drum 13 to the housing heads 19 of the wrapping drum 20. Similarly, and necessarily, in each support body 18 of the coupling drum 16 the "left" housing head 19 operates with a law of motion different from the "right" housing head 19 having to interact with respective wrapping heads 15 of the wrapping drum 13 having different laws of motion.

As illustrated in Figure 6, each support body 18 is hinged to the coupling drum 16 so as to rotate relative to the coupling drum 16 around a rotation axis 30 parallel to the rotation axis 17 of the coupling drum 16 (and spaced apart from the rotation axis 17) under the control of a cam actuator device which exploits the rotation of the coupling drum 16 around the rotation axis 17. Each support body 18 carries a pair of housing heads 19 arranged beside one another; each housing head 19 is hinged to the support body 18 so as to rotate relative to the support body 18 around a rotation axis 31 parallel to the rotation axis 30 (and spaced apart from the rotation axis 30) under the control of the cam actuator device. Moreover, each housing head 19 supports a corresponding coupling pocket which is adapted for housing (containing) an inner wrap 3 (namely a group 4 of cigarettes contained in an inner wrap 3) ; consequently, each support body 18 (indirectly) supports a pair of coupling pockets arranged in proximity of one another .

In use, in the transfer stations S3 and S4 each support body 18 rotates around the corresponding rotation axis 30 and, simultaneously, each housing head 19 rotates around the corresponding rotation axis 31; in this way the two coupling pockets of the same support body 18 remain facing to and aligned with the corresponding wrapping heads 15 in the transfer station S3 so as to receive in succession the inner wraps 3, and the two coupling pockets, of the same support body 18, are kept facing to and aligned with the corresponding wrapping head 22 in the transfer station S4 so as to release, together, the two inner wraps 3 joined to one another .

According to what is illustrated in Figure 7, each wrapping head 22 comprises an oblong shaped support element 32 (without cylindrical symmetry) which is mounted in a rotating manner on the wrapping drum 20 so as to rotate, relative to the wrapping drum 20, around a rotation axis 33 parallel to the rotation axis 21 of the wrapping drum 20 (and spaced apart from the rotation axis 21 itself) under the control of a cam actuator device which exploits the rotation of the wrapping drum 20 around the rotation axis 21; the rotation axis 33 is arranged eccentric relative to the support element 32, namely the rotation axis 33 is spaced apart from a barycenter of the support element 32. Moreover, each wrapping head 22 comprises a further support element 34 which is mounted in a rotating manner on the support element 32 so as to rotate, relative to the support element 32, around a rotation axis 35 parallel to the rotation axis 33 of the support element 32 (and spaced apart from the rotation axis 33 itself) under the control of the cam actuator device; the support element 34 has a cylindrical symmetry and the rotation axis 35 is arranged in a central position relative to the support element 34, namely the rotation axis 35 coincides with a central cylindrical symmetry axis of the support element 34. Finally, each wrapping head 22 comprises a seat 36 which is adapted to receive and house a collar 7 and two coupled inner wraps 3 and is mounted in a sliding manner on the support element 34so as to translate, relative to the support element 34, along a translation direction 37 which is perpendicular to the rotation axis 35 of the support element 34 and passes through the rotation axis 35 under the control of the cam actuator device.

In use, in the transfer stations S4 and S6 and in the feeding station S5 each support element 32 rotates around the corresponding rotation axis 33 and, simultaneously, each support element 34 rotates around the corresponding rotation axis 35; in this way the seat 36 is kept facing to and aligned with the corresponding feeding head 25 in the feeding station S5 for receiving a collar 7, the seat 36 is kept facing to and aligned with the corresponding two coupling pockets of the same support body 18 in the transfer station S4 for receiving together two inner wraps 3 coupled together, and the seat 36 is kept facing to and aligned with the corresponding wrapping pocket 28 in the transfer station S6 so as to release two inner wraps 3 coupled to one another together with a collar 7. In particular, the double rotation to which the seat 36 of each wrapping head 22 is subjected (namely the rotation around the rotation axis 35 and the simultaneous rotation around the rotation axis 33) allows to keep the seat 36 facing towards and aligned with the corresponding two coupling pockets of a same support body 18, in the transfer station S4, for a very extended length (approximately 25-35° of rotation of the wrapping drum 20 around the rotation axis 21) ; in other words, the transfer station S4 extends for a very extended length (approximately 25-35° of rotation of the wrapping drum 20 around the rotation axis 21) which allows to transfer two inner wraps 3 coupled to one another in a relatively long transfer time. In this way, it is possible to optimally perform (namely without ever losing full control of the inner wraps 3) the transfer of the inner wraps 3 from the two coupling pockets of a same support body 18 of the seat 36 of a wrapping head 22 even when the wrapping machine 8 operates at high speed. It is very important that in transferring a pair of inner wraps 3 from the two coupling pockets, of a same support body 18, to a wrapping head 22, the full control of the inner wraps 3 is never lost, as generally the inner wraps 3 are glue-free and if not properly held they tend to unfold, thus compromising the overall quality of the packets 1 of cigarettes. The embodiments described herein can be combined without departing from the scope of protection of the present invention .

The packing machine 8 described above has numerous advantages

In particular, the packing machine 8 allows to achieve a high hourly productivity (namely the number of packets 1 of cigarettes produced in the time unit) without, at the same time, compromising the final quality of the packets 1 of cigarettes. Among other things, this result is obtained due to the fact that the transfer station S4 extends over a very extended length ( indicatively 25-35° of rotation of the wrapping drum 20 around the rotation axis 21) and therefore it is possible to perform in an optimal manner (namely without ever losing full control of the inner wraps 3) the transferring of the inner wraps 3 from the two coupling pockets of a same support body 18 to the seat 36 of a wrapping head 22 even when the packing machine 8 operates at high speed. The embodiment illustrated in the attached figures refers to the manufacturing of a packet of cigarettes, but the present invention can be applied without substantial modifications also to the manufacturing of any other type of packet of smoking articles with a cylindrical shape (for example, a packet of cigars, a packet of liquid vaporizing type electronic cigarettes, a packet of new generation cigarettes without tobacco combustion... ) .

LIST OF THE REFERENCE NUMBERS OF THE FIGURES

1 packet of cigarettes

2 outer container

3 inner wrap

4 group of cigarettes

5 sheet of wrapping material

6 blank

7 collar

8 packing machine

9 forming unit

10 wrapping unit

11 coupling unit

12 wrapping unit wrapping drum

rotation axis

wrapping head

coupling drum

rotation axis

support bodies housing heads

wrapping drum

rotation axis

wrapping head

feeding drum

rotation axis

feeding head

wrapping drum

rotation axis

wrapping head

drying conveyor rotation axis rotation axis support element rotation axis support element rotation axis seat

translation direction feeding station transfer station transfer station transfer station feeding station transfer station feeding station