WO2014064613A1

WO2014064613A1 - Machine for making adjustably ventilated cigarettes

Info

Publication number: WO2014064613A1
Application number: PCT/IB2013/059542
Authority: WO
Inventors: Giuliano Gamberini; Gabriele BENNI; Massimo Sartoni
Original assignee: G.D S.P.A.
Priority date: 2012-10-26
Filing date: 2013-10-22
Publication date: 2014-05-01
Also published as: EP2911538B1; JP6392767B2; JP2015532836A; EP2911538A1; ITBO20120585A1

Abstract

The machine of the invention, for making adjustably ventilated cigarettes, comprises a unit (30) for turning a first portion (23) of cigarette (3) comprising a first slit (19); the turning unit (30) in turn comprises gripping means (34) for the first portion (23) and retaining means (35) for a second portion (24) of cigarette (3) comprising a second slit (20); the gripping means (34) are capable of imparting torque to the first portion (23) which, by turning about the axis (3a) of the cigarette (3) by a predetermined angle (θ), offsets the first slit (19) relative to the second slit (20), thus causing the second slit (20) to close.

Description

DESCRIPTION

MACHINE FOR MAKING ADJUSTABLY VENTILATED CIGARETTES Technical field

This invention relates to a machine for making adjustably ventilated cigarettes.

Background art

By "adjustably ventilated cigarette" is meant a cigarette which has on the outside surface of the filter one or more slits whose opening can be adjusted in such a way that the smoker can decide the degree to which the cigarette is aerated.

The opening of the external slits on the outside surface of the filter can be adjusted by turning a portion of the filter so that the external slits made on the outside surface of the filter are placed in a desired position relative to corresponding internal slits made in the filter itself.

More specifically, the maximum degree of ventilation is achieved when the external slits are exactly aligned with and perfectly match the internal slits, while the external slits are fully closed when the aforementioned filter portion is turned in such a way that the external slits are no longer in communication with the respective internal slits.

Usually, adjustably ventilated cigarettes are made with the external slits in the closed position, so as to give the smoker the possibility of increasing the degree of cigarette ventilation, on which the concentration of nicotine depends.

Known from document WO84/00478 is a method of making adjustably ventilated cigarettes.

This method involves conveying the cigarettes in a cigarette rotating device which comprises two conveyor belts and a skid plate, which is fixed relative to the conveyor belts. The cigarettes are placed between the two conveyor belts in such a way that at least one portion of the filter of each cigarette is in contact with the skid plate.

Thus, the filter portion which is in contact with the skid plate turns relative to the cigarette portion which is between the two conveyor belts and which remains fixed between the two belts. This turning movement causes the external slits of each cigarette to be offset relative to the internal slits made in the filter, thereby closing the internal slits.

This device is not free of disadvantages. In effect, skid plate wear may prevent the filter portion from being held firmly, allowing unwanted turning of the filter portion which is in contact with the skid plate itself.

This causes imprecise offsetting of the internal slits relative to the external slits, thus preventing the internal slits from being fully closed.

As a result, the cigarettes feeding out of the device are ventilated to different degrees, failing to meet the standards of quality required for the manufacture of the cigarettes.

Disclosure of the invention

This invention has for an aim to provide a machine for making adjustably ventilated cigarettes which is capable of making cigarettes having the same degree of ventilation and which is capable of turning a cigarette filter portion with greater precision than prior art devices.

The technical purpose indicated and the aims specified are achieved by a machine for making adjustably ventilated cigarettes which comprises the technical features set out in the independent claim 1 .

Brief description of drawings

The invention is described below with reference to the accompanying drawings, which illustrate a non-limiting embodiment of it, and in which: - Figure 1 is a schematic front view of a machine for making adjustably ventilated cigarettes according to this invention;

- Figure 2 is a scaled-up schematic front view of a detail from Figure 1 ;

- Figure 3 is a schematic front view of a first embodiment of a turning unit of the machine of Figure 1 ;

- Figure 4 is a side view of the turning unit shown in Figure 3;

- Figure 5 is a perspective view of the turning unit shown in Figure 3;

- Figure 6 is a schematic front view of a second embodiment of the turning unit of the machine of Figure 1 ;

- Figure 7 shows a scaled-up view of a detail of the turning unit of Figure 6;

- Figure 8 illustrates an adjustably ventilated cigarette in a configuration of maximum ventilation;

- Figure 9 illustrates an adjustably ventilated cigarette in a configuration of no ventilation;

- Figure 10 illustrates an adjustably ventilated cigarette, with some parts cut away in order to better illustrate others;

- Figure 1 1 is a scaled-up view, in cross section, of the cigarette of Figure 8;

- Figure 12 is a scaled-up view, in cross section, of a further detail from Figure 1 1 .

Detailed description of the preferred embodiments of the invention

With reference to Figure 1 , the numeral 1 denotes a machine for making adjustably ventilated cigarettes.

The machine 1 comprises a section 2 for making cigarettes 3 with filter tip 10 and comprising a unit 4 for feeding cigarette sticks 7, a unit 5 for feeding filter plugs 8 and a unit 9 for assembling the cigarette sticks 7 with the respective filter plugs 8.

The assembly unit 9 is located downstream of the unit 4 for feeding the cigarette sticks 7 and of the unit 5 for feeding the filter plugs 8, each wrapped in a respective wrapping sheet 22.

The assembly unit 9 is capable of associating a cigarette stick 7 with a respective filter plug 8.

More specifically, the assembly unit 9 receives from the feed unit 4 double filter sticks 7, the two in each pair being spaced from each other, and places a filter plug 8 between every two.

The filter plug 8 interposed between the two cigarette sticks 7 is also double, that is to say, will eventually define two filter tips 10, each associated with one cigarette stick 7.

The filter plug 8 may comprise one or more modular elements placed one after the other to make up the filter plug 8.

The assembly unit 9 comprises a rolling device 1 1 and a device 12 for feeding patches 13.

The rolling device 1 1 is designed to receive the patches 13 from the feed device 12.

The rolling device 1 1 receives two cigarette sticks 7 in succession with the filter plug 8 interposed between them and wraps a patch 13 around them to obtain a double cigarette 3.

The double cigarettes 3 are then cut at the filter plugs 8 to obtain a succession of cigarettes 3, each with a filter tip 10.

Each cigarette 3 has a main longitudinal axis of extension 3a.

Downstream of the assembly unit 9, a final roller unit, labelled 15 in its entirety, performs further finishing operations of known type on the cigarettes 3.

Each cigarette 3 with filter tip 10 feeding out of the unit 2 for making cigarettes 3 comprises a cigarette stick 7 and a filter tip 10 consisting of a core of filter material 21 wrapped in the wrapping sheet 22 which is in turn wrapped in the patch 13.

The patch 13 has a circumferential precut line 14 extending round the cylindrical outside surface of the cigarette 3. The patches 13 fed into the rolling device 1 1 may already have the precut lines 14 on them.

Alternatively, the machine 1 may comprise a device for making precut lines on the patches 13.

A laser perforating unit 16 is located downstream of the final roller unit 15. With reference in particular to Figures 1 and 2, the laser perforating unit 16 comprises a first conveying roller 17 and a laser perforating device 18 facing the outer periphery of the first conveying roller 17.

The first conveying roller 17, which rotates about its axis 17a in the direction indicated in Figures 1 and 2, receives the cigarettes 3, each with a filter tip 10, in succession.

During the rotation of the first roller 17, the laser perforating device 18 makes on each cigarette 3 a first slit 19 and a second slit 20, exactly aligned with the first slit 19.

The first and second slits 19 and 20 of each cigarette 3 are located between the precut line 14 of the respective patch 13 and the free end of the filter tip 10.

In an alternative embodiment not illustrated, the laser perforating unit 16 can make the circumferential precut line 14 on the patch 13 of each cigarette 3 with filter tip 10.

The first and second slits 19 and 20 are made, respectively, on a portion 13a of the patch 13 and on a portion 22a of the wrapping sheet 22 of the filter tip 10, lying under the portion 13a of the patch 13.

The first slit 19 is thus located on the outside surface of the cigarette 3 and the second slit 20 is located, relative to the first slit 19, inside the cigarette 3 since it is made on the portion 22a of the wrapping sheet 22 of the filter tip 10.

By varying the position of the first slit 19 relative to the second slit 20 it is possible to adjust the degree of ventilation of the cigarette 3, because air can pass through the filter tip 10 only if the first slit 19 is in communication with the second slit 20, otherwise there is no ventilation.

The highest degree of ventilation of the cigarette 3 is obtained when the first and second slits 19 and 20 are exactly superposed and matched because they allow air to enter the core of filter material 21 .

There is no ventilation of the cigarette 3 when the first and second slits 19 and 20 are mutually offset in such a way that they are not in communication with each other.

In other words, the cigarette 3 is in configuration of no ventilation when the second slit 20 is closed by the patch 13 above it, around the filter tip 10, thus preventing air from entering the core of filter material 21 .

It should be noted that the number of slits 19 and 20 is variable as a function of the degree of ventilation specified by manufacturers of cigarettes 3 with filter tip 10.

The position of the first slit 19 relative to the second slit 20 is adjusted by turning a first portion 23 of cigarette 3 relative to a second portion 24 of cigarette 3 about the axis 3a of the cigarette 3 with filter tip 10.

With reference in particular to Figures 8 and 10, the filter tip 10 of each cigarette 3 comprises a circumferential incision 6.

The circumferential incision 6, having the shape of a circular crown, extends from an inside edge 6a of the core of filter material 21 to the wrapping sheet 22, according to a section transversal to the axis 3a.

It should be noted that the first portion 23 overlaps the second portion 24, in particular at a portion of the filter tip 10 extending between the circumferential incision 6 and the precut line 14 along the direction of the axis 3a.

In other words, the first portion 23 comprises a portion of the filter tip 10 extending from the letter's free end to the incision 6 and a portion of the patch 13, comprising the first slit 19, extending from the free end of the filter tip 10 to the precut line 14, with reference to the axis 3a of the cigarette 3. In effect, the patch 13 is connected to the wrapping sheet 22 of the filter plug 8 along a first cylindrical surface 8a which extends from the free end of the filter tip 10 to the circumferential incision 6 and along a second cylindrical surface 8b which extends from the precut line 14 to the cigarette stick 7.

Preferably, the patch 13 is connected to the filter plug 8 on the first and second cylindrical surfaces 8a and 8b by adhesive means.

On the portion of the wrapping sheet 22 between the circumferential incision 6 and the precut line 14, the patch 13 is free to slide and, once the precut line 14 is broken, is caused to turn by the first portion 23 of cigarette 3.

Consequently, the second portion 24 comprises a portion of the filter tip 10 which is overlapped by and lies under the first portion 23 and which extends from the incision 6 to the precut line 14 and comprises the second slit 20 and the rest of the cigarette 3 which extends from the precut line 14 to the free end of the cigarette stick 7.

The first and second portions 23 and 24 are connected to each other solely by a length 21 a of filter material capable of twisting when the first portion 23 is turned relative to the second portion.

The circumferential incision 6 of the filter tip 10 may be made in the machine 1 by a dedicated cutting unit. Alternatively, the circumferential incision 6 may already be present in the filter plugs 8 which are fed to the machine 1 .

As mentioned above, at the outfeed of the laser perforating unit 16, the first and second slits 19 and 20 are exactly matched.

A second conveying roller 25, which rotates about its axis 25a in the direction indicated in Figures 1 and 2, is located downstream of the first conveying roller 17. The cigarettes 3 with the first and second slits 19 and 20 are received and spaced by the second roller 25 which conveys them towards a roller 26 for rolling the cigarettes 3. A tile 27 is opposed to the periphery of the rolling roller 26. The tile 27 has a cylindrical outside surface 28 facing the periphery of rolling roller 26. Preferably, the tile 27 comprises a relief element 29 on its outside surface 28, also opposed to the rolling roller 26.

The rolling roller 26, which rotates about its axis 26a in the direction indicated in Figures 1 and 2, receives the spaced cigarettes 3 from the second conveying roller 25 and conveys them towards the tile 27.

During the rotation of the rolling roller 26, the cigarettes 3 come into contact with the cylindrical outside surface 28 of the tile 27 and roll thereon.

More specifically, the relief element 29 is located on the cylindrical outside surface 28 so that as the cigarette 3 rolls thereon, the precut line 14 comes into contact with, and is broken by, the relief element 29.

It should be noted that once the precut line 14 is broken, the first portion 23 of cigarette 3 is free to turn about the axis 3a of the cigarette 3.

In an alternative embodiment not illustrated, the relief element 29 of the rolling roller 26 is located along a peripheral stretch of the rolling roller 26 opposed to the cylindrical outside surface 28 of the tile 27. In this alternative embodiment, too, the relief element 29 breaks the precut line 14 of the patch 13 of each cigarette 3 as the cigarette 3 rolls on the periphery of the roller 26.

It should be noted that the spacing of the cigarettes 3 conveyed by the second conveying roller 25 is proportional to the circular arc which the cigarettes 3 must travel as they roll on the rolling roller 26 and on the cylindrical outside surface 28 of the tile 27.

The machine 1 comprises a turning unit 30 by which the first portion 23 of each cigarette 3 is turned and which puts the cigarettes 3 in the configuration of no ventilation, that is to say, with the second slit 20 in the closed condition.

The turning unit 30 turns the first portion 23 relative to the second portion 24 in order to offset the first slit 19 relative to the second slit 20, in such a way that they are not in communication.

The turning unit 30 comprises a roller 31 for conveying the cigarettes 3, which turns about its axis 31 a in the direction indicated in Figures 1 and 2 and on which the respective first portions 23 of the cigarettes 3 are turned. A third conveying roller 32, with axis 32a, is located downstream of the rolling roller 26.

The third roller 32 receives the spaced cigarettes 3 from the rolling roller 26 and conveys them towards the conveying roller 31 .

The conveying roller 31 comprises a plurality of flutes 33, each housing a cigarette 3.

The flutes 33 are located along the cylindrical outside surface 39 of the conveying roller 31 in such a way that the axes 3a of the cigarettes 3 housed in the flutes 33 are parallel to the axis of rotation 31 a of the conveying roller 31 .

The turning unit 30 comprises gripping means 34 for the first portion 23 and retaining means 35 for the second portion 24 of each cigarette 3. More specifically, the gripping means 34 are capable of imparting torque to the first portion 23 and turning it by a predetermined angle Θ relative to the second portion 24.

The first portion 23 is turned by the gripping means 34 about the axis 3a of the cigarette 3 by the predetermined angle Θ, thereby causing the second slit 20 to be closed and thus putting the cigarette 3 in the configuration of no ventilation.

This turning action is obtainable by the twist in the length 21 a of filter material connecting the first portion 23 to the second portion 24.

The retaining means 35 are movable at a speed equal to the rotation speed of the conveying roller 31 and act in conjunction therewith to retain the second portions 24 of the cigarettes 3, keeping them fixed relative to the first portions 23 which turn about the axes 3a of the respective cigarettes 3.

More precisely, the retaining means 35 act in conjunction with the conveying roller 31 along a circular arc A defined by a subtended angle Θ1 .

The first slit 19 might also turn relative to the second slit 20 along a circular arc B lying within the circular arc A and defined by a subtended angle Θ2 smaller than the subtended angle Θ1 .

The subtended angle Θ2 is, in practice, proportional to the rotation Θ to be imparted to the first slit 19 in order to offset it relative to the second slit 20. Downstream of the turning unit 30 there is an outfeed roller 48, which rotates about its axis 48a in the direction indicated in Figures 1 and 2 and which picks up the cigarettes 3 with the first portion 23 turned and the second slit 20 positioned in its closed configuration.

The outfeed roller 48 conveys the cigarettes 3 out of the machine 1 .

Described below are different embodiments of the turning unit 30 of the machine 1 , which differ mainly in the form of the retaining means 35 and of the gripping means 34.

Figures 3 to 5 illustrate a first embodiment of the turning unit 30.

In this embodiment, the retaining means 35 comprise a motor-driven belt 36.

The belt 36 is movable at the same speed as the conveying roller 31 .

The belt 36 is trained around a motor-driven roller 37 and at least one idle roller 38. Preferably, the belt 36 is trained around two idle rollers 38.

The motor-driven roller 37 and the idle rollers 38 have respective axes of rotation 37a and 38a which are parallel to each other. More specifically, the axes of rotation 37a and 38a are parallel to the axis 31 a of the conveying roller 31 .

The motor-driven belt 36 has at least one stretch T which faces the cylindrical outside surface 39 of the conveying roller 31 .

More specifically, the stretch T of the belt 36 extends along the circular arc A defined by the subtended angle Θ1 .

The stretch T of the belt 36 is positioned close to the cylindrical surface 39 of the conveying roller 31 , and more specifically, at a distance such as to retain and hold in position the cigarettes 3, at the second portions 24 of the cigarettes 3 themselves as they pass between the belt 36 and the conveying roller 31 .

The width of the motor-driven belt 36 is less than or equal to the width of the second portion 24 of cigarette 3, so as to hold each cigarette 3 in the respective flute 33 of the conveying roller 31 .

The gripping means 34 comprise an upper motor-driven belt 40 and a lower motor-driven belt 41 on opposite sides of the cigarettes 3.

The upper belt 40 and the lower belt 41 comprise respective stretches T1 and T2 which are opposite each other and parallel to the circular arc B defined by the subtended angle Θ2.

The upper belt 40 and the lower belt 41 are spaced from each other by a distance such as to retain and hold the cigarettes 3, at the first portions 23 of the cigarettes passing between the upper and lower belts 40 and 41 . Preferably, the width of the upper belt 40 and of the lower belt 41 is less than or equal to that of the first portions 23 of the cigarettes 3 to be turned.

The upper belt 40 and the lower belt 41 define an upper contact element and a lower contact element, respectively, for the cigarettes 3 conveyed by the conveying roller 31 .

The upper belt 40 is trained around a first motor-driven roller 42, which rotates about its axis 42a, and a first idle roller 43, which rotates about its axis 43a.

Preferably, the axes 42a and 43a of the first motor-driven roller 42 and of the first idle roller 43, respectively, are coaxial with the axes 37a and 38a of the rollers 37 and 38, respectively, around which the motor-driven belt 36 in contact with the second portion 24 of the cigarettes 3 is trained. The lower belt 41 is trained around a second motor-driven roller 44, which rotates about its axis 44a, and a second idle roller 45, which rotates about its axis 45a.

The upper belt 40 and the lower belt 41 are driven, respectively, by the first and second motor-driven rollers 42 and 44 at a different speed from that of the motor-driven belt 36 and, consequently, of the conveying roller 31 .

More specifically, the upper belt 40 and the lower belt 41 each move at a respective speed which differs by the same amount from the speed of the motor-driven belt 36.

More precisely, the upper belt 40 moves at a feed speed which is greater than the speed of the motor-driven belt 36 and the lower belt 41 moves at a feed speed which is less than the speed of the motor-driven belt 36. It should be noted that the motor-driven belt 36, the upper belt 40 and the lower belt 41 move in a direction of feed which is concordant with the direction of rotation of the conveying roller 31 .

Alternatively, the lower belt 41 moves at a feed speed which is greater than the speed of the motor-driven belt 36 and the upper belt 40 moves at a feed speed which is less than the speed of the motor-driven belt 36. That way, the upper belt 40 and the lower belt 41 apply to the first portions 23 of the cigarettes 3 a pair of opposing forces which generate the torque which allows the first slit 19 to be turned relative to the second slit 20 by the predetermined angle Θ, offsetting them and putting the respective cigarette 3 in the configuration of no ventilation.

Figures 6 and 7 illustrate a second embodiment of the turning unit 30.

This embodiment differs from the first embodiment in that the lower contact element of the gripping means 34 is not a lower motor-driven belt 41 .

In effect, in this embodiment, the gripping means 34 of the turning unit 30 comprise at least two supporting rollers 46 for each cigarette 3 conveyed by the conveying roller 31 .

The axes of rotation 46a of the supporting rollers 46 are parallel to the axis 31 a of the conveying roller 31 .

Preferably, the supporting rollers 46 are aligned with each other and positioned at the same distance from the centre of rotation of the conveying roller 31 .

The supporting rollers 46 define the contact elements of the gripping means 34.

More specifically, the supporting rollers 46 are idle rollers.

With reference in particular to Figure 7, a detector roller 47 is associated with each flute 33 of the conveying roller 31 in order to detect the presence of the cigarette 3 in the respective flute 33.

The detector roller 47, whose axis 47a is parallel to the axes 46a of the supporting rollers 46, is normally in contact with the first portion 23 of the cigarette 3 housed in the respective flute 33.

In other words, associated with each cigarette 3 are a pair of supporting rollers 46 and a detector roller 47.

In this embodiment of the turning unit 30, it is the upper motor-driven belt 40 that applies the force which produces the torque on the first portion 23 of cigarette 3.

As the cigarette 3 turns about its axis 3a, the idle supporting rollers 46 turn in the direction opposite to the direction of rotation of the cigarette 3.

When the cigarette 3 feeds out of the turning unit 30, the first slit 19 and the second slit 20 on it are offset by the predetermined angle Θ.

Lastly, it should be noted that the breaking of the precut line 14 may occur on the turning unit 30, when the first portions 23 are turned.

In effect, the torque imparted to the first portions 23 by the gripping means 34 may be sufficient to break the precut line 14 and to turn the first portions 23 themselves.

Thus, the turning unit 30 may be located immediately downstream of the laser perforating unit 16.

Advantageously, the turning unit 30 of the machine 1 allows the first portion 23 of each cigarette 3 to be precisely turned relative to the second portion 24 in order to place the first slit 19 at a predetermined position relative to the second slit 20.

More specifically, in the embodiments described, the first slit 19 is turned relative to the second slit 20 by an angle Θ in such a way that the first slit 19 itself is no longer in communication with the second slit 20, thus placing the cigarette 3 in a configuration of no ventilation.

This is possible because the gripping means 34 operate actively and directly on the first portions 23 of the cigarettes 3, while the retaining means 35 keep the second portions 24 of the respective cigarettes 3 fixed while the first portions 23 turn.

On being fed out of the machine 1 according to the invention, the cigarettes 3 all have the same degree of ventilation, thus minimizing production rejects.

Lastly, it should be noted that the turning unit 30 may consist of a configuration kit applicable to the outfeed end of a machine for making adjustably ventilated cigarettes.

Claims

1 . A machine for making adjustably ventilated cigarettes, comprising a section (2) for making filter-tipped cigarettes; the section (2) comprising a unit (4) for feeding cigarette sticks (7), a unit (5) for feeding filter plugs (8) each wrapped in a respective wrapping sheet (22), a unit (9) for assembling the cigarette sticks (7) with the filter plugs (8), a device (12) for feeding patches (13) and a rolling device (1 1 ) designed to receive the patches (13) and wrapping a patch (13) round at least one portion of cigarette stick (7) and a respective filter plug (8) to make a succession of cigarettes (3) with filter tip (10) with a longitudinal axis (3a); each cigarette (3) with filter tip (10) has a respective circumferential precut line (14) and at least a first slit (19) made in the patch (13) and a second slit (20) made in the wrapping sheet (22) of the filter plug (8) and matching the first slit (19); the machine (1 ) comprising a unit (30) for turning a first portion (23) of the cigarette (3) comprising the first slit (19); the turning unit (30) comprising gripping means (34) for the first portion (23) and retaining means (35) for a second portion (24) of the cigarette (3) comprising the second slit (20); the gripping means (34) being capable of imparting torque to the first portion (23) which, by turning about the axis (3a) of the cigarette (3) by a predetermined angle (Θ), offsets the first slit (19) relative to the second slit (20), thus causing the second slit (20) to close.

2. The machine according to claim 1 , characterized in that the turning unit (30) comprises a roller (31 ) for conveying the cigarettes (3) and on which the respective first portions (23) are turned; the cigarettes (3) having respective axes (3a) which are parallel to the axis of rotation (31 a) of the conveying roller (31 ) and being positioned substantially at the cylindrical outside surface (39) of the selfsame roller (31 ); the retaining means (35) being movable at a speed equal to the rotation speed of the conveying roller (31 ) and acting in conjunction with the conveying roller (31 ) to retain the second portions (24) along a circular arc (A) defined by a subtended angle (Θ1 ).

3. The machine according to claim 2, characterized in that the retaining means (35) are positioned in the proximity of the cylindrical outside surface (39) of the conveying roller (31 ) at a defined distance such as to retain and hold in place the cigarettes (3) which are interposed between the retaining means (35) and the selfsame conveying roller (31 ) at the respective second portions (24).

4. The machine according to any one of claims 1 to 3, characterized in that the retaining means (35) comprise a motor-driven belt (36) which is movable at the same speed as the conveying roller (31 ); the belt (36) comprising at least one stretch (T) which faces the conveying roller (31 ) and which is parallel to the circular arc (A).

5. The machine according to any one of claims 1 to 4, characterized in that the gripping means (34) comprise an upper contact element (40) and a lower contact element (41 , 46) opposite to each other relative to the cigarettes (3) conveyed by the roller (31 ); at least one of the two contact elements (40, 41 ) being motor-driven and being movable at a speed different from that of the retaining means (35) and of the conveying roller (31 ) in such a way as to impart the torque to the first portion (23) of each cigarette (3).

6. The machine according to any of claims 1 to 5, characterized in that the upper contact element comprises an upper motor-driven belt (40) comprising a stretch (T1 ) extending parallel to the conveying roller (31 ); the stretch (T1 ) extending along a circular arc (B) defined by a subtended angle (Θ2) proportional to the rotation (Θ) to be imparted to the first portion (23) in order to close the second slit (20).

7. The machine according to any one of claims 1 to 6, characterized in that the lower contact element comprises a lower motor-driven belt (41 ) comprising a stretch (T2) extending parallel to the circular arc (B); the upper belt (40) and the lower belt (41 ) each moving at a respective speed which differs by the same amount from the speed of the retaining means (35); the upper belt (40) moving at a feed speed which is greater than the speed of the retaining means (35) and the lower belt (41 ) moving at a feed speed which is less than the speed of the retaining means (35), or vice versa.

8. The machine according to any one of claims 1 to 7, characterized in that the lower contact element comprises at least two supporting rollers (46) for each cigarette (3) conveyed by the conveying roller (31 ); the supporting rollers (46) being idle rollers.

9. The machine according to any one of claims 1 to 8, characterized in that the turning unit (30) comprises a roller (26) for rolling the cigarettes (3), located upstream of the conveying roller (31 ), and a tile (27) having a cylindrical outside surface (28) facing the cylindrical outside surface (39) of the conveying roller (31 ); each cigarette (3) rolling on the cylindrical outside surface (28) of the tile (27) and on the cylindrical outside surface (39) of the rolling roller (26); one of either the rolling roller (26) or the tile (27) comprising a relief element (29) to break the precut line (14) of the patch (13) of each cigarette (3) during the rolling of the cigarette (3) itself.

10. The machine according to any one of claims 1 to 9, characterized in that the tile (27) comprises the relief element (29) on its cylindrical outside surface (28) which faces the roller (26) for rolling the cigarettes (3).

1 1 . The machine according to any one of claims 1 to 10, characterized in that it comprises a laser unit (16) for perforating the cigarettes (3) with filter tip (10) and located upstream of the turning unit (30); the laser perforating unit (16) being designed to make the first and second slits (19, 20) and/or the circumferential precut line (14) on the patch (13) of each cigarette (3) with filter tip (10).

12. The machine according to any one of claims 1 to 1 1 , characterized in that the laser perforating unit (16) makes the first and second slits (19, 20) between the precut line (14) of the respective patch (13) and the free end of the filter tip (10); the first and second slits (19, 20) being made, respectively, at a portion (13a) of the patch (13) and at a portion (22a) of the wrapping sheet (22) of the filter tip (10), under the portion (13a) of the patch (13).

13. A kit applicable to the outfeed end of a machine for making adjustably ventilated cigarettes according to any one of claims 1 to 12, characterized in that it comprises a turning unit (30) comprising gripping means (34) for the first portion (23) comprising the first slit (19) and retaining means (35) for a second portion (24) of cigarette (3) comprising the second slit (20); the gripping means (34) and the retaining means causing the first portion (23) to turn relative to the second portion (24) by imparting a torque to the first portion (23) which, by turning about the axis (3a) of the cigarette (3) by a predetermined angle (Θ), offsets the first slit (19) relative to the second slit (20), thereby causing the second slit (20) to close.