The present invention relates to an apparatus for separating a first pack and a second pack which are arranged in a stack, to a heat-shrinking apparatus comprising such separating apparatus, and to corresponding methods.

Consumer goods, for example smoking articles, are frequently packed in containers which are wrapped by an outer wrapper of a plastics material for protecting the goods from moisture, for preserving the taste of the goods, or for many additional purposes.

Packs of smoking articles, for example cigarettes, are often further packed into a cartridge containing a plurality of such packs. For example, twenty such packs are packed into one cartridge, with the packs being arranged in the cartridge in stacks of two packs.

Typically, packs of smoking articles are wrapped by an outer wrapper of a heat-shrinkable plastics material. One example for a heat-shrinkable plastics material is polypropylene. After wrapping the outer wrapper of the heat- shrinkable material around the cigarette pack the wrapper must be exposed to heat so as to allow the outer wrapper to shrink to tightly enclose the pack and to provide a proper wrinkle-free appearance.

The packs being provided with the outer wrapper which is not yet heat-shrinked may typically be transported in stacks of two packs. Where packs can be transported in a stack two walls of the packs, for example the front wall of one pack and the back wall of the other pack, abut against one another in the stack. These abutting walls cannot be properly exposed to heat. This may lead to a reduced quality appearance of the heat-shrinking of the outer wrapper. Therefore, according to the art, the packs are separated in a shrink tunnel such that they can enter above and below a central heating plate.

The present invention suggests a novel apparatus for separating a first pack and a second pack which are arranged in a stack. The stack is movable on a transport path. The apparatus comprises a deflection unit comprising at least one deflection device. The at least one deflection device has at least one pair of rotatable rollers which are positioned laterally adjacent to the transport path. A first roller of the at least one pair of rollers is positioned at one side of the transport path for engaging a first side wall of the first pack. The second roller of the at least one pair of rollers is positioned at the other side of the transport path for engaging a second side wall of the first pack engaged by the first roller. The at least one pair of rotatable rollers is arranged to define a deflection path, and this deflection path includes an acute angle with the transport path of the stack. Thus, the apparatus allows for separation of the first pack from the second pack by creating a space between the first pack and the second pack. In general, the deflection of the packs is directed substantially in the direction normal to the plane of the abutting walls of the first and second pack. Preferably, the deflection is effected such that the pack only translates during the deflection without or with only little rotation. This facilitates the introduction of the deflected pack between the corresponding heating plates. In particular, this may provide an increase in machine speed. Further, it may reduce or prevent damage to the pack that may be caused by a rotation and counter rotation of the pack to align the deflected pack into a position that allows heat- shrinking .

While generally the first and second packs of the stack can be arranged laterally adjacent to one another, preferably the first and second packs are arranged one above the other in the stack. The deflection unit may comprise one or more deflection devices. With the aid of the one or more deflection devices the packs are spatially separated from one another so that the large walls of the separated packs can subsequently be exposed to heat to cause heat-shrinking of the outer wrapper.

In one embodiment of the separating apparatus accor ^¬ ding to the invention, the at least one pair of rollers is arranged at a first position relative to the transport path for engaging the first pack, for example the upper pack. The at least one pair of rollers define a first deflection path. The first deflection path runs upwards relative to the transport path of the stack. In this embodiment, the upper pack is deflected upwards so that a space is created between the upper pack and the lower pack. The lower pack is transported further in the direction of the transport path. After heat-shrinking of the outer wrapper of both packs the upper pack may be transported downwards again to form a stack with the lower pack again. Alternatively, the lower pack can be transported upwards to form a stack with the upper pack again. The stack can then be further processed. For example, the stack of the two packs with the heat-shrinked outer wrappers can be placed into a cartridge. As a further alternative, the first pack could travel back on top of the second pack due to gravity, instead of being actively transported .

The term "upwards" as used in this context is to be understood to mean a direction that is substantially perpendicular to the transport direction of the stack of packs. Preferably, the term "upwards" refers to a direction that comprises at least one component that is directed opposite to the direction of gravity. The term "downwards" is likewise used to refer to a direction which in substantially opposite to the "upwards" direction. Nevertheless, it is in the spirit of the invention to also encompass embodiments, where the general transport direction of the stack of packs is vertical. In that case, the "upward" direction would be a horizontal movement.

In another embodiment of the separating apparatus according to the invention, the at least one pair of rollers is arranged at a second position relative to the transport path for engaging the second pack, for example the lower pack. The at least one pair of rollers define a second deflection path. The second deflection path runs downwards relative to the transport path of the stack. In this embodiment, the lower pack is deflected downwards so that a space is created between the lower pack and the upper pack. The upper pack is transported further in the direction of the transport path. Also in this embodiment, after heat-shrinking of the outer wrapper of both packs the lower pack may be transported upwards again to form a stack with the lower pack again. Alternatively, the upper pack can be transported downwards to the lower pack to form a stack with the lower pack again. The stack can then be further processed. For example, the stack of the two packs with the heat-shrinked outer wrappers can be placed into a cartridge.

In a still further embodiment of the separating apparatus of the invention the deflection unit comprises at least two deflection devices. The two deflection devices comprise a first deflection device for defining the first deflection path running upwards relative to the transport path of the stack. The first deflection device comprises at least one pair of rollers. The at least one pair of rollers of the first deflection device is arranged in the first position relative to the transport path of the stack for engaging the first pack of the stack (the upper pack) . The two deflection devices further comprise a second deflection device for defining the second deflection path running downwards relative to the transport path of the stack. The second deflection device also comprises at least one pair of rollers. The at least one pair of rollers of the second deflection device is arranged at the second position relative to the transport path of the stack for engaging the second pack of the stack (the lower pack) . Both the first and second deflection paths each include an acute angle with the transport path. This embodiment is advantageous in that the two packs are both deflected thus increasing the spatial distance between the first and second packs . In accordance with another aspect of the separating apparatus according to the invention each deflection device comprises at least two pairs of rollers. This embodiment provides for an improved engagement and transport of the pack along the respective deflection path. In addition, due to the deflection path being longer the spatial distance between the separated first and second packs is increased.

In any of the afore-mentioned embodiments of the separating apparatus according to the invention, the acute angle is preferably between about 2 degrees to about 15 degrees, and preferably is within about 2.5 degrees to about 7.5 degrees. In this respect, the term "about" is to be understood to also comprise and specify the respective exact values. This allows for a sufficient spatial separation of the first and second packs while allowing a high machine speed. Further, damage to the packs that may be caused by the change of direction can be thus avoided or reduced. Further, the required spatial distance can be achieved without the need for a long deflection path which allows for a compact build of the apparatus according to the invention.

A further aspect of the invention is related to an apparatus for heat-shrinking the outer wrappers of a first pack and a second pack arranged in a stack. The first pack and the second pack are each individually wrapped with an outer wrapper. The outer wrappers are made of a heat- shrinkable material, for example of polypropylene. The heat- shrinking apparatus comprises:

- a separation device in accordance with any of the embodiments described above;

- a transport device for transporting the separated first and second packs along spatially separated exposure paths through the heat-shrinking apparatus; and

- a heating unit arranged to apply heat to the outer wrappers of the separated first and second packs during the transport of the first and second packs on the exposure paths.

After the first and second packs are separated, the packs can be transported individually along spatially separated exposure paths through the heat-shrinking apparatus, so that the large walls of the packs, for example the front and rear walls of the packs, can be exposed to heat to cause the heat- shrinking of the outer wrapper. The heating unit is arranged to apply heat to the outer wrappers as they are transported on the spatially separated exposure paths. Such an apparatus allows for an effective and reliable heat-shrinking of the outer wrapper. The packs may be stopped within the heating unit to support the complete heat-shrinking of the wrapping material .

In one embodiment of the heat-shrinking apparatus according to the invention the heating unit comprises at least three heating plates. The three heating plates comprise a first heating plate which is arranged above the exposure path of the first pack, a second heating plate which is arranged below the exposure path of the first pack and above the exposure path of the second pack, and a third heating plate which is arranged below the exposure path of the second pack. This embodiment is advantageous since it is simple from a in constructional point of view.

A further aspect of the invention relates to a method of separating a first pack and a second pack which are arranged in a stack. The stack is moved on a transport path. The method comprises the step of deflecting the first pack or the second pack from the transport path to move the deflected pack on a deflection path. The deflection path includes an acute angle with the transport path to create a space between the first pack and the second pack. The advantages of the separating method are already mentioned above when discussing the advantages of the separating apparatus.

In one embodiment of the separating method according to the invention, the first pack and the second pack are deflected from the transport path in opposite directions on first and second deflection paths, respectively. This embodiment is particularly advantageous since it increases the spatial distance between the separated packs, as has already been discussed above.

Still a further aspect of the invention relates to a method of heat-shrinking the outer wrappers of a first pack and a second pack arranged in a stack. The first pack and the second pack are each individually wrapped with an outer wrapper. The outer wrappers are made of a heat-shrinkable material, for example they are made of polypropylene. The heat-shrinking method comprises the steps of

- separating the first pack and the second pack using any of the embodiments of the separating method discussed above;

- transporting the separated first and second packs along spatially separated exposure paths, and

- applying heat to the outer wrappers of the separated first and second packs during the transport along the spatially separated exposure paths. The advantages of this method are already discussed above when discussing the corresponding heat-shrinking apparatus according to the invention.

In one embodiment of the heat-shrinking method according to the invention the steps of transporting the separated first and second packs and applying heat to the outer wrappers of the separated first and second packs com prise the steps of - transporting the separated first pack on a first exposure path extending between a first heating plate arranged above the first exposure path and a second heating plate arranged

below the first exposure path, and

- transporting the separated second pack on a second exposure path extending between the second heating plate arranged above the second exposure path and a third heating plate arranged below the second exposure path. This embodiment is effective and reliable and allows for an easy constructional solution for the corresponding apparatus.

Further advantageous aspects and embodiments of the invention will become apparent from the following description of embodiments of the invention with the aid of the schematic drawings in which: Fig. 1 shows a first embodiment of essential parts of the separating apparatus according to the invention and of the heat shrinking apparatus according to the invention, and

Fig. 2 shows a front view of the heating plates of the heat-shrinking apparatus with two separa ^¬ ted packs being transported along first and second exposure paths extending between the heating plates.

Fig. 1 shows a first (upper) cuboidal pack 1 and a second (lower) cuboidal pack 2 which are arranged one above the other in a stack. The stack is transported along a transport path, the direction of which is indicated by the arrow 3. A deflection unit 4 comprises a first deflection device 40 and a second deflection device 41.

The first deflection device 40 of the embodiment shown comprises two pairs 400 and 401 of rollers which are arranged laterally adjacent to the transport path. Only one roller of each pair 400, 401 of rollers can be seen in Fig. 1. The first roller of the pair 400 is arranged laterally adjacent to and in a first position relative to the transport path at to engage a first side wall of the upper cuboid pack 1. The non-visible roller of the pair 400 of rollers engages a second side wall of the upper cuboid pack 1. The second pair 401 of rollers of the first deflection device 40 is arranged in a similar manner.

The first pair 400 of rollers and the second pair 401 of rollers of the first deflection device are arranged to define a first deflection path which is indicated by the dashed line 402. The first deflection path 402 includes an acute angle a (alpha) with the transport path the direction of which is represented by the arrow 3 and runs upwards relative to the transport path.

The second deflection device 41 also comprises two pairs of rollers 410 and 411, from which only one roller is visible. The first pair of rollers 410 and the second pair of rollers 411 of the second deflection device define a second deflection path which is indicated by the dashed line 412. The second deflection path 412 also includes an acute angle a with the transport path represented by the arrow 3 and runs downward relative to the transport path. Although the acute angles a are shown to be identical they may be different. Also, in general only one deflection device may be sufficient, and each deflection device may only have one pair of rollers or may have three or more pairs of rollers. The embodiment shown in Fig. 1 comprises two such deflection devices 40 and 41, and each of the deflection devices 40 and 41 comprises two pairs of rollers. The angle a is preferably between about 2 degrees and about 15 degrees, and more preferable the angle a is between about 2.5 and about 7.5 degrees .

Downstream of the deflection unit 4 when viewed in the direction of transport of the packs a heating unit 5 is shown. The heating unit 5 of the embodiment shown comprises three heating plates 50, 51 and 52.

The operation of the apparatus is as follows. At the time the stacked upper pack 1 and lower pack 2 reach the deflection unit 4, the first pair 400 of rollers of the first deflection device 40 drivingly engages the opposite side walls of the upper pack 1. The engaged upper pack 1 is then deflected along the first deflection path 402 and is further transported in a direction towards the heating plates 50, 51 with the aid of the second pair 401 of rollers of the first deflection device 40. Similarly, the first pair 410 of rollers of the second deflection device 41 drivingly engage the opposite side walls of the lower pack 2. The engaged lower pack 2 is then deflected along the second deflection path 412 and is further transported in a direction towards the heating plates 51, 52 with the aid of the second pair 410 of rollers of the second deflection device 41.

Fig. 2 shows the separated packs 1 and 2 as they are further transported along their respective first (upper) exposure path 500 and second (lower) exposure path 501 (see Fig.l) . The large walls of the wrapped packs 1 and 2 (outer wrapper not visible) can then be exposed to heat. For exam ^¬ ple, the heating plates 50 and 51 can be gently pressed against the outer wrapper of the upper pack 1 thus causing the shrinking of the outer wrapper of the upper pack 1. Similarly, the heating plates 51 and 52 can be gently pressed against the outer wrapper of the lower pack 2 thus causing the shrinking of the outer wrapper of lower pack 2.

Once shrinking has been completed, the upper pack 1 and lower pack 2 can be moved along respective paths to form a stack again (not shown) . The stack of the packs 1 and 2 can then be further processed, for example the stack can be placed into a cartridge.