EP2922757B1

EP2922757B1 - Method and related apparatus for the production of a sealed wrapper

Info

Publication number: EP2922757B1
Application number: EP14727897.2A
Authority: EP
Inventors: Fiorenzo Draghetti
Original assignee: Gima TT SpA
Current assignee: Gima TT SpA
Priority date: 2013-05-06
Filing date: 2014-04-30
Publication date: 2017-11-22
Anticipated expiration: 2034-04-30
Also published as: WO2014181161A1; EP2922757A1

Description

Field of application

The present invention refers to a method for the production of a sealed containment wrapper for a bundle of cigarettes, in particular a wrapper made of a thermoplastic material intended to enclose the cigarettes inside a traditional rigid or semi-rigid package.
The invention further refers to the containment wrapper itself and the related apparatus for its production.
The invention has practical applications particularly in the tobacco industry.

Prior art

Traditionally cigarettes are packaged in rigid or semi-rigid packages, inside of which they are enclosed in a wrapper that is usually made of aluminium foil.
Although this solution is widely adopted, this type of wrapper represents a compromise between production costs and the need to keep the aromatic qualities of the cigarette tobacco unaltered.
For the purpose of better preserving the organoleptic qualities of the product, it would in fact certainly be preferable to seal the internal containment wrapper, made from a sheet of thermoplastic film that is sealed along the perimeter of the bundle of cigarettes contained therein.
However, known thermosealing techniques cannot be applied without taking additional measures for the realization of a wrapper in the manner described above. These techniques in fact employ thermosealing heads that apply pressure to the overlapping flaps of the sheet of film that is to be sealed. These sealing heads, when being applied directly over the bundle of cigarettes, can however cause damage to the latter due to the heat that is transmitted or the pressure that is applied.
To overcome this drawback it would therefore be necessary to introduce a stiffening board between the thermosealing member and the cigarettes, so that the cigarettes retain their shape and consistency. This solution presents an economic drawback, however, both in the sense of the additional material needed for the production of the stiffening board and for the mechanical complications this introduces for the manufacturing machinery, which will have to perform an additional operation, namely the introduction of the stiffening board.
Furthermore the presence of a board folded in a U-shape around the bundle of cigarettes inside the wrapper requires that an access opening in the wrapper is located on the side opposite the board, with constructional complications as a result.
US 3378187 discloses a package which is produced by folding a wrapper into a U-shape on the outside of a mandrel with a strip positioned between the mandrel and the wrapper. In particular, the strip closes an end of the mandrel located in the area folded into a U-shape and extends through a slit in the wrapper so that it extend outside the wrapper, permitting the strip end to be pulled to tear the wrapper to gain access to the cigarettes. US 3378187 also discloses a method for the production of a sealed wrapper of a bundle of cigarettes, comprising the steps of: providing a bundle of cigarettes; providing a covering liner; providing a rigid casing for the precisely measured containment of the bundle of cigarettes, said rigid casing presenting a longitudinal extension and comprising two smaller opposite walls and two larger opposite walls, an entry opening and an exit opening that open at the opposite ends; folding the covering liner into a U-shape on the outside of the rigid casing, said covering liner forming a pair of lateral flaps that exits from each of the two smaller walls of the rigid casing; inserting the bundle of cigarettes into said rigid casing through said entry opening; performing a first sealing, wherein said covering liner , located on the outside of the rigid casing, is sealed along the two opposite smaller walls so as to create around the rigid casing a tubular containment wrapper that is sealed on the sides; extracting the bundle of cigarettes together with said tubular containment wrapper from said rigid casing by means of a pushing member that acts on the bundle of cigarettes moving from the entry opening towards the exit opening, in order to have the bundle of cigarettes placed directly inside the containment wrapper in such a way that the rigid casing is no longer placed between the bundle of cigarettes and the containment wrapper that is sealed on the sides ; lastly performing a final sealing step, wherein the tubular containment wrapper is sealed on the open side, so as to obtain a complete seal of the containment wrapper containing the bundle of cigarettes , without any element being placed between the containment wrapper and the bundle of cigarettes.
US 2009/038269 discloses a package which is produced by folding a wrapper into a U-shape on the outside of a mandrel. The lateral sides of the package are closed by folding over each other the lateral edges of the wrapper against the lateral wall of the mandrel. US 2009/038269 does not provide a perfect sealed package.
The technical problem that is the basis of the present invention is therefore to devise a method for the production of a sealed containment wrapper for a bundle of cigarettes that ensures a correct containment and that at the same time facilitates access to the cigarettes while keeping the production costs acceptable.

Summary of the invention

The above-mentioned technical problem is solved by a method according to claim 1.
A person skilled in the art will be able to appreciate that the provisional rigid casing, on the outside of which a large part of the necessary sealing process to close the containment wrapper takes place, makes the use of a stiffening board inside the containment wrapper superfluous.
This rigid casing, advantageously made of a thin material, may be filled with the cigarettes that are to be packaged and subsequently the bundle of cigarettes and the partially sealed containment wrapper are extracted together from the rigid casing to leave the cigarettes in direct contact with the covering liner, and with the weakening line that allows access to the cigarettes positioned in an area without any folds.
One will note that the operations described above of introducing the bundle of cigarettes and extracting the bundle of cigarettes generically indicate relative motions wherein the cigarettes are moved inside the rigid casing on the one hand, and on the other the rigid casing is extracted away from the combined bundle of cigarettes with wrapper. Both relative motions can either be performed by moving one or the other or by moving both elements mentioned: for example, the extraction of the bundle of cigarettes can be in the form of, as it is in the preferred embodiment described below, pushing away the bundle of cigarettes, by which the wrapper is pulled along with the bundle away from the rigid casing that is held in a fixed position; alternatively, longitudinally sliding the rigid casing between the wrapper and the bundle of cigarettes is also a possibility.
A further advantage of the method described above derives from the fact that, to obtain the containment wrapper the covering liner can be folded into a U-shape directly on the outside of said rigid casing. The casing then performs the additional function of assisting, because it defines a solid base for the shaping of the generally parallelepiped form of the containment wrapper.
More particularly the step of the folding of the containment wrapper can be performed by means of a U-shaped folding member (punch) that slides over the rigid casing. This folding member, encountering on its path the covering liner, pushes and folds the film around the exterior of the rigid casing.
In the course of the above-mentioned first sealing step, the adjacent lateral flaps of the covering liner folded into a U-shape can be sealed together two by two.
In this manner the two end flaps of the liner remain open, so that the cigarettes may be extracted from the casing before the final sealing step.
Then, in the final sealing step, the two end flaps of the covering liner can be sealed together.
In the above-mentioned first sealing step the adjacent lateral flaps, on both sides of the covering liner, can be brought nearer each other and joined together on the outside of a lateral wall of the rigid casing, and then clamped and sealed together by the first sealing members that operate opposite said lateral faces.
In the course of the final sealing step, the two end flaps may be made to overlap each other and fastened between second opposite sealing members.
With this method of sealing the end flaps, the sealing member is not placed opposite the bundle of cigarettes and the rigid casing therefore no longer needs to be present in the last step of the final sealing.
In the step of the introduction of the bundle of cigarettes, the bundle of cigarettes is preferably introduced with the cigarette filters turned in the direction of the area of the covering liner that is folded into a U-shape.
This production method is particularly advantageous as the end with the cigarette filter is generally turned in the direction of the top opening of the rigid external package containing the cigarettes. Once the top lid of the package has been opened, the consumer can access the containment wrapper that has its U-shaped area of covering liner turned towards the consumer. This area presents a continuous surface uninterrupted by sealing lines, which is aesthetically pleasing to the consumer.
A line of weakening is included in this U-shaped area to allow the consumer easy opening of the wrapper by means of an adhesive tab.
The aforementioned rigid casing presents a longitudinal extension with a first opening and a second opening at opposite extremities, said first opening being covered by the containment wrapper that has been partially sealed at the end of the first sealing step; said step of extracting the bundle of cigarettes involves the application of a pushing action on the bundle of cigarettes beginning at said second opening, in such a manner that the bundle of cigarettes is made to exit from the first opening, pulling the partially sealed containment wrapper along with it. The containment wrapper, pulled by the bundle of cigarettes, slides along longitudinally against the exterior of the rigid casing.
This production method is particularly advantageous because it defines, without any mechanical complications, a moving away of the combined bundle of cigarettes and wrapper, so that the rigid casing slides out from between the bundle of cigarettes and the partially sealed wrapper.
In a particularly advantageous manner the pushing action exercised on the bundle of cigarettes can be performed by means of a pushing member held by a pushing shaft, said rigid casing comprising a longitudinal gap intended to let this pushing shaft pass through from the entry opening to the exit opening.
The technical problem identified above is also solved by a containment wrapper made according to the preceding indications.
The technical problem is also solved by an apparatus according to claim 9, which is advantageously able to carry out the previously described method.
In this apparatus the rigid casing can have a longitudinal extension, with at opposite extremities a first exit opening for the bundle of cigarettes, and a second entry opening for the bundle of cigarettes, said extraction means of the bundle of cigarettes comprising a pushing member that acts upon the bundle of cigarettes from the second opening towards the first opening.
The rigid casing can in particular have a longitudinal gap that extends from the first opening to the second opening, said pushing member comprising a pushing head having a contact surface that comes in contact with the bundle of cigarettes, said pushing head being supported by a pushing shaft that is slidably operable inside said longitudinal gap.
The apparatus comprises a first rotating drum, comprising a plurality of rigid casings solidly attached to the drum.
Further characteristics and advantages will become apparent from the detailed description to follow, of a preferred but not exclusive embodiment of the present invention with reference to the figures included as non-limiting examples.

Brief description of the drawings

Figures 1 - 10 schematically illustrate the succession of steps of the method according to the present invention for the production of a sealed containment wrapper for a bundle of cigarettes;
Figure 11 illustrates a sealed wrapper of a bundle of cigarettes according to the present invention;
Figure 12 illustrates in a schematic manner an apparatus for the production of a sealed containment wrapper for a bundle of cigarettes according to the present invention.

Detailed description

With reference to the enclosed figures, in particular to figure 11, the reference number 1 generically indicates a sealed containment wrapper for a bundle of cigarettes made in accordance with the present invention.
The containment wrapper 1, preferably made of a thermoplastic material, has a substantially box-like form, in other words the shape of a rectangular parallelepiped, and it covers in direct contact a bundle of cigarettes 10 arranged in the ordered manner traditionally used in the field.
The containment wrapper 1, in particular, has six faces: two opposite main lateral faces 14, which define the external sides with the largest size of the parallelepiped; two secondary lateral faces 15, also opposite each other and instead defining the external sides of smaller size; and lastly a top face 16 and a bottom face 17 at the two longitudinally opposite extremities.
One will note that the top face 16 is arranged to face the top opening of a traditional rigid or semi-rigid cigarette package surrounding the containment wrapper 1. More particularly it has a weakening line 18 that allows the user to tear away part of the containment wrapper 1 to create an access window to the cigarettes contained therein, preferably reclosable by means of an adhesive tab.
The containment wrapper 1 is made from a single sheet of covering liner 11, folded into a U-shape over a rigid casing 20 at said top face 16.
The covering liner 11 thus folded over the rigid casing 20 defines two facing pairs of opposite lateral flaps 12 and, after the casing has been extracted, also two end flaps 13 are formed, also opposite and facing each other. These flaps are coupled, clamped and sealed together in order to define the secondary faces 12, and the bottom face 17, the latter having been created by the coupling of the end flaps 13.
The methods for folding and sealing will become clearer from the description to follow, which is according to the method of the embodiment of the present invention illustrated in the enclosed figures 1-10. This method is described with reference to the apparatus 100 schematically illustrated in figure 12, which advantageously allows the method to be executed in an automated manner.
The method according to the present invention in particular employs a rigid casing 20, whose purpose will be better understood from the following description and which is precisely measured to contain the bundle of cigarettes.
This rigid casing 20 is in the shape of a hollow rectangular parallelepiped that extends in a longitudinal direction x and that has at its opposite ends a first opening 21 and a second opening 22. In addition to the two opposite openings, the parallelepiped that defines the rigid casing 20 further comprises two smaller lateral walls 24 and two larger lateral walls 25.
The larger and smaller lateral walls 24, 25 are all of a relatively small thickness. Externally they present a smooth surface, and internally a wavy surface of protuberances 28 and depressions 29 located longitudinally that match the external perimeter of a bundle of cigarettes 10, arranged in their packaging configuration.
One of the larger lateral walls 25 is interrupted in a longitudinal direction by a longitudinal slot 23 whose function will become clearer from the following description, which connects the first opening 21 to the second opening 22.
The transverse section of the rigid casing 20 is commensurate with the corresponding transverse section of the containment wrapper 1 that it is intended to obtain. On the other hand the longitudinal direction is greater in comparison with said containment wrapper, and it presents a lateral flanging at the second opening.
In the apparatus 100 according to the invention, the rigid casings 20 are preferably a plurality of casings mounted solidly along the external perimeter of a first rotating drum (not shown in the enclosed figures) with rotational axis parallel to the longitudinal axis x of the casings. The rigid casings 20 are mounted with their transverse axes tangential to the first rotating drum.
Thanks to the rotation of the first rotating drum on which the rigid casings 20 are mounted, each single rigid casing 20 can be made to pass through the first four stations that constitute a first part of the steps of the method for the production of a containment wrapper 1 according to the present invention.
A first station 101 includes means for folding the covering sheet 11 in a U-shape. These means for folding into a U-shape in particular comprise a first U-shaped folding member 60 that is arranged to slide over the rigid casing 20 when the latter finds itself at the first station 101.
In this step, represented in the enclosed figure 1, the covering liner 11 is stretched between the first folding member 60 and the extremity of the first opening 21 of the rigid casing 20. By making the first folding member 60 slide, the covering liner 11 is pulled along and a central portion of it is made to adhere to the first opening 21 and the two lateral portions, symmetrical between them, are folded against the two opposite greater walls 25 of the rigid casing 20.
In this way the containment wrapper 1 is formed, which at this time is still open on three sides, as can be seen in figure 2. Along each smaller wall 24 of the rigid casing 20 the two opposite lateral flaps 12 are joint facing each other by a transverse flap 19 in the area folded into a U-shape 27.
One will note that in the area folded into a U-shape 27 the central portion of the covering liner 11, extended over the first opening 21 of the rigid casing 20, presents the weakening line 18 that will later enable the opening of an access window to the bundle of cigarettes 10.
A second station 102 of the apparatus 100 includes means for the insertion of said bundle of cigarettes into said rigid casing 20. In particular these insertion means comprise a pushing block 70, reciprocatingly movable along the longitudinal direction x of the rigid casing aligned with the second station 102.
In this step, illustrated in the enclosed figure 3, the bundle of cigarettes 10 is accompanied by the pushing block 70 into the rigid casing 20 through the second opening 22, until they come into contact with the central portion of the covering liner 11 that covers the first opening 21, at the area folded into a U-shape 27. Note that the bundle of cigarettes 10 is inserted with the filters turned in the direction of the first opening 21, or, in other words, in the direction of the area folded into a U-shape 27 of the covering liner 11, at the weakening line 18.
In practice the bundle of cigarettes will be inside the rigid casing 20 and the covering liner 11 will be on the outside of the rigid casing 20.
In other words the rigid casing 20 is placed between the bundle of cigarettes 10 and the covering liner 11.
A third station 103 of the apparatus 100 includes means for the folding of the transverse flaps 19 of the covering liner 11 in the area folded into a U-shape 27 against the sides of the rigid casing 20; also included are first sealing means 40 to apply a first sealing of the lateral flaps 12 that extend along the lateral walls 24 of the rigid casing 20.
The folding means comprise a second folding member 80 in the shape of a C, arranged to slide over the rigid casing 20 against the first opening 21 in the area folded into a U-shape 27. Said second folding member 80 comprises two opposite arms 82 with dimensions that are such that they enclose the lateral walls 24 of the rigid casing 20, in order to press the transverse flaps 19 against the lateral walls 24 of the rigid casing 20, in order to form a lateral tuck 19a on each of the smaller walls 24.
This second folding member 80 operates in a first step, illustrated in figure 4, of the folding and sealing process performed in the third station 103. In this step, the second folding member 80 slides to enclose the bottom of the rigid casing 20 in the area folded into a U-shape 27. By doing this its arms 82 fold the transverse flaps 19 of the central portion of the covering liner 11 that stick out from the bottom of the rigid casing 20. These transverse flaps 19 are thus folded against the two lateral walls 24 of the rigid casing 20.
The first sealing means 40 are in the form of two thermosealing bars that are able to move towards each other, fastening the two facing lateral flaps 12 between them and applying the thermosealing. In this configuration for thermosealing, the first sealing members 40 abut against the two opposite lateral walls 24 of the rigid casing 20.
The first sealing means 40 are activated in a second step, illustrated in figure 5, of the sealing method performed at the third station. In this step said first sealing members are joined together with the two facing lateral flaps 12 in-between.
In practice, after having folded the transverse flaps 19 against the lateral walls 24 of the casing 20 to form the two tuck 19a, the next step is folding each of the two pairs of facing lateral flaps 12 of the covering liner 11 against the smaller lateral wall 24 of the rigid casing 20 to form two corresponding tabs that are perpendicular to the smaller wall 24 of the rigid casing 20. These perpendicular tabs 24 are joined together by means of thermosealing by the first sealing members 40 in order to form a fin 12a that finds itself in an overhanging configuration regarding each of the lateral walls 24 of the rigid casing 20.
These first thermosealing members 40 are in the form of sealing grippers that operate in juxtaposition to the lateral walls 24.
In this manner the partially sealed containment wrapper 1 is formed, which has the form of a pouch that is open on one side only.
The fins 12a are subsequently folded 90° and made to adhere to the covering liner 11 along the respective lateral wall 24 of the rigid casing 20 from which they depart.
A fourth station 104 of the apparatus 100 includes means for the extraction of the bundle of cigarettes 10 together with the partially sealed containment wrapper 1 from the rigid casing 20. These means for the extraction of the bundle of cigarettes in particular comprise a movable pushing member 30 held by a pushing shaft 31. More particularly this pushing member 30 has a contact surface, intended to come into contact with the bundle of cigarettes 10 and to perform a pushing action on these. In the course of its movement forward, the pushing member 30 is inserted into the rigid casing 20 through the second opening 22, and as a result it comes up against the bundle of cigarettes 10 which are then pushed out of the rigid casing 20 through the first opening 21, proceeding in its movement until the bundle of cigarettes 10 and the containment wrapper 1 associated with it arrive at a second rotating drum, not shown in the enclosed figures. As they pass through the rigid casing 20, the pushing shaft 31 of the pushing member 30 slides inside the longitudinal slot 23 of the rigid casing 20.
In this step, represented in the enclosed figure 7, the movement of the aforementioned pushing group 30 makes it possible to extract the bundle of cigarettes 10 from the rigid casing 20 together with the containment wrapper 1 formed by the covering liner 11. In effect, given that the cigarettes are in contact with the containment wrapper 1 through the first opening 21, the cigarettes in their movement pull along all of the wrapper 1, extracting the fixed rigid casing 20 placed between the bundle of cigarettes and the wrapper.
In practice, in the step of extracting the bundle of cigarettes 10 from the rigid casing 20, the bundle of cigarettes 10 pulls along with it the partially sealed wrapper, which slides on the outside of the rigid casing 20 until it comes in direct contact with the bundle of cigarettes 10.
In this manner the rigid casing 20 that was previously placed between the wrapper and the bundle of cigarettes, is extracted.
By choosing a very reduced thickness for the pouch, the wrapper will adhere perfectly to the bundle of cigarettes when the latter is extracted from the pouch.
Thanks also to the fact that the internal surface of the rigid casing 20 has undulations formed by longitudinal protuberances 28 and depressions 29 shaped to arrange the cigarettes in an ordered and contained manner, the adherence of the covering liner 11 - already sealed laterally to form the wrapper 1 - to the bundle of cigarettes is perfect.
Basically, each cigarette rests in a respective depression.
Lastly the containment wrapper 1 and the bundle of cigarettes contained therein are brought to the second rotating drum, which carries them in sequence to the terminal stations 106 known in the art for the folding of the end flaps 13 and the final sealing of these.
The sealing on the bottom wall of the bundle of cigarettes 10 occurs in a manner analogous to the one of the lateral walls 24.
In effect, a third folding member 90 first folds the sides of the end flaps 13 of the covering liner 11 and presses them against the bottom wall of the bundle of cigarettes 10 in order to form two lateral tucks 13a at the bottom of the bundle of cigarettes 10. The facing end flaps 13 of the covering liner 11 are folded against the bottom wall of the bundle of cigarettes 10 in order to form two corresponding tabs that are perpendicular to the bottom wall of the bundle of cigarettes 10. Subsequently these are joined together by means of thermosealing by the second sealing members 50, in order to form in the joining area a fin 13b that is perpendicular to the bottom wall of the bundle of cigarettes 10. These second sealing members 50 operate in juxtaposition to the bottom wall of the bundle of cigarettes.
Lastly the fin 13b is folded and made to adhere to the covering liner 11 against the bottom wall of the bundle of cigarettes 10.
In this manner a hermetic wrapper is produced containing the bundle of cigarettes 10 with the weakening line 18 situated on the smooth part without any folds so that it is easy to have access to the bundle of cigarettes 10.
The final steps of folding and sealing performed by the end stations 106 are illustrated in the enclosed figures 8 and 9.
From this description one will appreciate that the method, the wrapper and the apparatus according to the present invention make it possible to meet the requirements and overcome the drawbacks mentioned in the introduction of this description with reference to the prior art.
In fact, it is possible to obtain a hermetic wrapper with weakening line for access to the cigarettes without the need to include a board between cigarettes and wrapper.
Obviously a person skilled in the art will be able to apply numerous modifications and variations to the findings described above, all of which, however, fall within the scope of the invention as defined by the following claims.

Claims

Method for the production of a sealed wrapper (1) of a bundle of cigarettes (10), comprising the steps of:
providing a bundle of cigarettes (10);

providing a covering liner (11) having a weakening line (18) to provide access to the bundle of cigarettes (10);

providing a rigid casing (20) for the precisely measured containment of the bundle of cigarettes (10), said rigid casing (20) presenting a longitudinal extension and comprising two smaller opposite walls (24) and two larger opposite walls, an entry opening (22) and an exit opening (21) that open at the opposite ends;

folding the covering liner (11) into a U-shape on the outside of the rigid casing (20), with the weakening line (18) located in the area folded into a U-shape (27), which blocks the exit opening, said covering liner (11) forming a pair of lateral flaps (12) that exits from each of the two smaller walls (24) of the rigid casing (20);

inserting the bundle of cigarettes (10) into said rigid casing (20) through said entry opening;

performing a first sealing, wherein said covering liner (11), located on the outside of the rigid casing (20), is sealed along the two opposite smaller walls (24) so as to create around the rigid casing (20) a tubular containment wrapper (1) that is sealed on the sides;

extracting the bundle of cigarettes (10) together with said tubular containment wrapper (1) from said rigid casing (20) by means of a pushing member (30) that acts on the bundle of cigarettes (10) moving from the entry opening towards the exit opening, in order to have the bundle of cigarettes placed directly inside the containment wrapper (1) in such a way that the rigid casing (20) is no longer placed between the bundle of cigarettes (10) and the containment wrapper (1) that is sealed on the sides; lastly

performing a final sealing step, wherein the tubular containment wrapper (1) is sealed on the open side, so as to obtain a complete seal of the containment wrapper (1) containing the bundle of cigarettes (10), without any element being placed between the containment wrapper (1) and the bundle of cigarettes (10),

wherein said first sealing comprises the steps of:
folding by means of a folding member (80) transverse flaps (19) on the sides of the area folded into a U-shape (27) and pressing these against the respective smaller wall (24) of the rigid casing (20) in order to form a lateral tuck (19a) on each of the smaller walls (24) in the proximity of the area folded into a U-shape (27);

folding each of the two pairs of facing lateral flaps (12) of the covering liner (11) against the smaller wall (24) of the rigid casing (20) in order to form two corresponding tabs that are perpendicular to the smaller wall (24);

by means of thermosealing fusing the two tabs together in order to form in the fused area a fin (12a) that is perpendicular to the smaller wall (24), said thermosealing being performed by means of first sealing members (40) that operate in juxtaposition to said smaller walls (24) forming a pouch;

folding the fins (12a) and making them adhere to the covering liner (11) along the respective smaller wall (24);
Method according to claim 1 or 2, wherein the final sealing step comprises the clamping together of the two end flaps (13) of the tubular containment wrapper (1) by means of second sealing members (50).
Method according to any of the preceding claims, wherein the bundle of cigarettes (10) is inserted into the rigid casing (20) with their respective filters turned to come into contact with the area folded into a U-shape (27) of the covering liner (11) at the weakening line (18).
Method according to any of the previous claims, wherein said pushing member (30) comprises a pushing shaft (31) that in the phase of extracting the bundle of cigarettes from the rigid casing (20) passes through a longitudinal slot (23) in one of the larger walls of the rigid casing (20).
Method according to any of the previous claims, wherein the final sealing step comprises:
folding by means of a folding member (90) the sides of the end flaps (13) of the covering liner (11) and pressing them against the bottom wall of the bundle of cigarettes (10) in order to form two lateral tucks (13a) on the bottom of said bundle of cigarettes (10);

folding the facing end flaps (13) of the covering liner (11) against a bottom wall (17) of the bundle of cigarettes (10) in order to form two corresponding end tabs that are perpendicular to the bottom wall (17) of the bundle of cigarettes (10);

by means of thermosealing fusing the two end tabs together in order to form in the fused area an end fin (13b) that is perpendicular to the bottom wall of the bundle of cigarettes (10);

folding the end fin (13b) and making it adhere to the covering liner (11) along the bottom wall (17) of the bundle of cigarettes (10).
Method according to any of the previous claims, wherein the rigid casing on the inside presents an undulated surface comprising longitudinal protuberances (28) and depressions (29) shaped to match the external perimeter of the bundle of cigarettes (10).
Sealed wrapper (1) for a bundle of cigarettes (10) realized according to any of the previous claims.
Apparatus for the production of a sealed wrapper (1) of a bundle of cigarettes (10), comprising:
a rigid casing (20) precisely measured to temporarily contain the bundle of cigarettes (10), said rigid casing (20) having a longitudinal extension and comprising two opposite smaller walls (24) and two opposite larger walls (25), an entry opening (22) and an exit opening (21) which open at the opposite ends;

first folding means (60) intended to fold a covering liner (11) into a U-shape on the outside of said rigid casing (20), said covering liner (11) having a weakening line (18) to provide access to the bundle of cigarettes (10) in the area folded into a U-shape (27), said covering liner (11) forming a pair of lateral tabs (12) that exits from each of the two smaller walls (24) of the rigid casing (20);

introductory means (70) to insert said bundle of cigarettes (10) into said rigid casing (20) through the entry opening (22), until the bundle of cigarettes (10) comes into contact with the covering liner (11) that covers the exit opening (21), at the area folded into a U-shape (27);

second folding means (80) for folding the transverse flaps (19) on the sides of the area folded into a U-shape (27) of the covering liner (11) and pressing them against the respective smaller wall (24) of the rigid casing (20) in order to form a lateral tuck (19a) on each of the smaller walls (24) in the proximity of the area folded into a U-shape (27); folding means for folding each of the two lateral flaps (12) of the covering liner (11) against the smaller wall (24) of the rigid casing (20) in order to form two corresponding tabs that are perpendicular to the smaller wall (24);

first sealing means (40) that operate in juxtaposition to said smaller walls (24) to join by means of thermosealing each of the two pairs of facing lateral tabs (12) of the covering liner (11), in order to form in the fused area a fin (12a) that is perpendicular to the smaller wall (24) and to form a partially sealed containment wrapper (1) containing the rigid casing (20);

extraction means to extract said bundle of cigarettes (10) from said rigid casing (20) by entering into the rigid casing (20) in order to push out the bundle of cigarettes (10) through the exit opening (21, so that said rigid casing (20) is no longer placed between said bundle of cigarettes (10) and said partially sealed wrapper (1);

second sealing means (50) to apply a final sealing wherein the open side of the containment wrapper (1) is sealed.
Apparatus according to claim 8, wherein said first sealing means (40) are configured in such a way as to form in the joining area a fin (12a) that is perpendicular to the smaller wall (24).
Apparatus according to claim 8 or 9, wherein said rigid casing (20) presents a longitudinal slot (23) that extends from the first opening (21) to the second opening (22), said extraction means (30) comprising a pushing head having a contact surface that comes into contact with the bundle of cigarettes (10), said pushing head being supported by a pushing shaft (31) that can be operated slidingly inside said longitudinal slot (23).
Apparatus according any of claims 8-10, comprising at least a rotatable drum around the circumference of which a plurality of said rigid casings (20) is attached.
Apparatus according any of claims 8-11, wherein the rigid casing (20) internally has an undulating surface comprising longitudinal protuberances (28) and depressions (29) shaped to match the external perimeter of the bundle of cigarettes (10).