EP4637397A1

EP4637397A1 - Machine for the production of cigarettes presenting a first graphic pattern and a second graphic pattern

Info

Publication number: EP4637397A1
Application number: EP23840779.5A
Authority: EP
Inventors: Fausto Mengoli; Ivan Eusepi
Original assignee: GD SpA
Current assignee: GD SpA
Priority date: 2022-12-20
Filing date: 2023-12-15
Publication date: 2025-10-29
Also published as: WO2024134413A1; CN120390591A

Abstract

A machine (1) for making cigarettes (P), having a first graphic design (M1) on the tobacco side (P1), and a second graphic design (M2) on the filter side (P2) and aligned with the first graphic design (M1). The machine (1) comprises at least one sensor (600) to detect the position and/or the orientation of the first graphic design (M1) and of the second graphic design (M2) on each cigarette (P), and a control unit (U) connected to the sensor (600) and configured to adjust the forming of the cigarettes (P) as a function of a position and/or orientation deviation between the first and the second graphic design (M1, M2).

Description

DESCRIPTION

MACHINE FOR THE PRODUCTION OF CIGARETTES PRESENTING A FIRST GRAPHIC PATTERN AND A SECOND GRAPHIC PATTERN

Technical field

The present invention relates to a machine and a method for making cigarettes, having a first graphic design on the tobacco side and a second graphic design on the filter side and aligned with the first graphic design.

In the present description, the expression “graphic design” is understood to mean any graphic representation, such as (but not limited to) an image, a logo, an alphanumerical character, writing (a combination of alphanumerical characters) a drawing and/or symbol, for example.

Background art

To-date, the need is felt to provide cigarettes having graphic designs on the outer surface of the cigarette, specifically made on the filter side and on the tobacco side. Furthermore, the need is greatly felt for such graphic designs to be mutually aligned to ensure a correct attractive appearance and formal precision of the article (think of the case of an image, with two portions thereof needing to be mutually aligned so that the image is recognizable.

However, to-date, due to the complexity of the production process, the machines configured to make such type of cigarettes do not allow large scale production devoid of rejects.

In fact, as the creation of the two graphic designs is provided in different operating steps (generally one in the “maker” section of the tobacco side of the system and one in the “filter tip assembling” section of the system) and, likewise, it is provided on different components (which will make up the cigarette at a later time), the aforesaid machines are not capable of ensuring sufficient creation accuracy in the finished article. Specifically, also with a highly accurate calibration of the different machine portions, slight delays or phase shifts frequently occur, which, on a large-scale production, persist or even add up in time, creating whole batches of faulty articles or nonetheless articles of unsatisfactory quality.

Think, for example, of the timing of the cork paper feed line for producing connecting strips in the filter tip assembling machine, provided with graphic designs. Such timing, even if carried out finely with the previous forming line of tobacco segments, externally showing, in turn, graphic designs, which must be aligned with the graphic designs of the connecting strips, can change in time, as the two forming lines can be subject to misalignments, rubbing of the materials and so on. Such drawbacks are gradual and persist in time or increase, resulting in the whole successive production being affected, at a certain point, by insufficient quality.

Object of the invention

In this context, the technical task underlying the present invention is to provide a machine and a method for making cigarettes, having a first graphic design on the tobacco side and a second graphic design on the filter side and aligned with the first graphic design, which overcome the drawbacks of the aforesaid prior art.

Specifically, it is the object of the present invention to provide a machine and a method for making cigarettes, having a first graphic design on the tobacco side and a second graphic design on the filter side and aligned with the first graphic design, capable of ensuring high quality precision of the finished product.

The specified technical task and object are achieved by a machine and a method for making cigarettes, comprising the technical features presented in claims 1 and 11 , respectively, and/or in one or more of the dependent claims.

Brief of the

The present invention will now be described with reference to the accompanying drawings, showing a non-limiting embodiment thereof, in which:

- figure 1 shows a diagrammatic side view of an embodiment of a machine for making cigarettes according to the present invention;

- figure 2 shows a diagrammatic front view of the machine in figure 1 ;

- figure 3 shows an embodiment of a cigarette made using the machine in figures 1 and 2.

According to the accompanying figures, reference numeral “1 ” globally denotes a machine for making cigarettes. Such cigarettes, hereinafter indicated with reference “P”, are shown by way of example in figure 3.

Detailed description of preferred embodiments of the invention

In detail, the cigarettes “P” are formed by the juxtaposition of a tobacco piece (tobacco side “P1 ”) and by a filter piece (“P2”) and have a first graphic design “M1 ” on the tobacco side “P1 ” and a second graphic design “M2” on the filter side “P2”. Specifically, the first graphic design “M1 ” is aligned with the second graphic design “M2”.

In the present description, the expression “graphic design” is understood to mean any graphic representation, such as an image, a logo, an alphanumerical character, writing (a combination of alphanumerical characters), a drawing and/or a symbol, for example. Such graphic design can be made by printing, embossing or other methods (the application method is not limiting). Furthermore, the first and second graphic designs “M1 ”, “M2” can be of the same type (both printed or both embossed, for example) or of different type, for example, the first graphic design “M1 ” could be made by printing and the second “M2” by embossing, or vice versa.

According to figure 1 , the machine 1 comprises a tobacco segment forming unit 100 configured to make a continuous rod “B” provided on the outside with a succession of first graphic designs “M1 ” and to cut subsequently the continuous rod “B” into tobacco segments “ST” each having at least one graphic design “M1 ”. Such tobacco segments “ST” are therefore fed in ordered succession, one after the other.

In detail, the tobacco segment forming unit 100 comprises a feeder 103 for a continuous stream of a filling material “R”, specifically tobacco fibers. According to known solutions, the feeder 103 is of the type comprising a suction conveyor belt 104 of the known type, which has a closed loop structure on at least two rollers and a lower branch connected to a suction chamber for holding, in suspension, a layer of tobacco, previously received from an ascending chimney, successively released in an unloading section 106. The tobacco segment forming unit 100 further comprises a support for at least one roll 101 of a paper web and a paper feed line 102, configured to feed the paper web unwound from the roll 101 .

A forming beam 105 is operatively located downstream of the feeder 103 and of the paper feed line 102, for making the continuous rod “B” by wrapping the filling material “R” with the paper web. Thereby, according to a known technology, the forming of the succession of tobacco segments “ST” is performed by unwinding the paper web from the roll 101 , feeding the paper web along the paper feed line 102 and successively gradually wrapping the web around a continuous stream of filling material “R” released in the unloading station 106 obtaining a continuous rod “B” provided with a longitudinal joining line, generally arranged at the top or nonetheless in an upper zone of the rod.

Located downstream of the forming beam 105, the tobacco segment forming unit 100 comprises a cutting device 107 configured to cut the continuous rod “B” into tobacco segments “ST”, each having at least one graphic design “M1 ”.

The tobacco segment forming unit 100 is preferably configured to make double-length tobacco segments “ST”, each having a pair of graphic designs “M1 ” on the outside surface thereof. However, the invention is equally applicable to the solution in which the tobacco segments “ST” cut by the cutting device 107 already have a single length, corresponding to the length taken in the finished cigarette.

According to an aspect of the present invention, the tobacco segment forming unit 100 comprises at least one applicator device 110, e.g. a printing plate or an embosser, located along the paper feed line 102, upstream of the forming beam 105, for applying a succession of first graphic designs “M1 ” on the paper web at a position that the graphic design is located on the outer surface of the continuous rod “B” and preferably in a position opposite the stated longitudinal joint. Specifically, as will be more apparent in the continuation of the present description, the applicator device 110 is adjustable transversely to the paper web to adjust the lateral position of the first graphic designs “M1 ” on the paper web.

Downstream of the tobacco segment forming unit 100, the machine 1 comprises a filter segment feed unit 200.

In detail, the filter segment feed unit 200 comprises a hopper 201 containing a plurality of filter pieces “F0” having multiple lengths. The filter segment feed unit 200 comprises a first drum 202 configured to take the filter pieces “F0” from the hopper 202 and, together with a cutting tool, cut the filter pieces “F0” obtaining the filter segments “SF”. The filter segment feed unit 200 further comprises one or more further drums 203 located downstream of the first drum 202 and configured (in a substantially known manner) to transversely offset and successively laterally align the filter segments “SF” cut by the same piece “F0” obtaining a succession of filter segments “SF” transversely moved one after the other.

Preferably, the filter segment feed unit 200 is configured to feed filter segments “SF” having a double length to combine each of such segments “SF” with a pair of tobacco segments “ST”. However, the invention is equally applicable to the solution in which the filter segments “SF” have a single length, corresponding to the length taken in the finished cigarette, and they are individually connected to a single respective tobacco segment “ST”.

According to figure 1 , the machine 1 comprises a successive combining unit 300, which is operatively located downstream of the tobacco segment forming unit 100 and downstream of the filter segment feed unit 200. The combining unit 300 is configured to receive and combine the aforesaid successions of tobacco segments “ST” and filter segments “SF” to form a succession of groups of segments “GS”, each comprising at least one tobacco segment “ST” and one filter segment “SF” abutted end to end.

The combining unit 300 is preferably configured to feed a succession of double segment groups “GS”, each made up of two tobacco segments “ST” separated by a double-length filter segment “SF”. Specifically, the combining unit 300 is configured to make a transverse cut half way along each of the double-length tobacco segments “ST” so as to obtain a pair of single-length tobacco segments “ST”, to axially spread the single-length tobacco segments “ST” apart from each other and to insert a respective double-length filter segment “SF” between two tobacco segments “ST” that have been spread apart, so as to feed a succession of double segment groups “GS”, each made up of two tobacco segments “ST” separated by a double-length filter segment “SF”.

For this purpose, the combining unit 300 comprises a collecting drum 301 configured to collect the succession of double-length tobacco segments “ST”, a cutting and spreading drum 302 configured to cut the doublelength tobacco segments “ST”, together with a respective cutting tool, so as to obtain a pair of single-length tobacco segments “ST” and axially spread them. The combining unit 300 also comprises a combining drum 303, adapted to receive the double-length filter segments “SF” and to receive the aforesaid single-length tobacco segments “ST”, which are located abutting on opposite ends of the double-length filter segment “SF”. According to figure 1 , the machine 1 further comprises a connecting strip forming unit 400 configured to feed a succession of connecting strips “F” each having on the outside surface at least one second graphic design “M2”, and to apply a connecting strip “F” on the outside surface of each group of segments “GS” coming from the combining unit 300. The connecting strip forming unit 400 comprises feed means 401 configured to feed a continuous paper strip “SC” having a succession of second graphic designs “M2”, along a feed path.

The connecting strip forming unit 400 further comprises a cutting and applicator device 402, located downstream of the feed means 401 and configured to transversely cut the continuous paper strip “SC”, so as to obtain a succession of connecting strips “F” each having at least one respective second graphic design “M2” in a predetermined position, and to apply each connecting strip “F” to the outer surface of a respective group of segments “GS” coming from the combining unit 300.

In detail, the feed means 401 of the connecting strip forming unit comprise an unwinding apparatus 403 configured to unwind, in a controlled manner, the continuous paper strip “SC” from a feed roll 404 and to feed the continuous paper strip “SC” to the cutting and applicator device 402.

The connecting strip forming unit 400 is preferably configured to make double connecting strips “F”, each having a pair of second graphic designs “M2” arranged mirror symmetrically to each other (with respect to a longitudinal axis of symmetry) and to apply the double connecting strip “F” on the outside surface of each double segment group “GS” coming from the combining unit 300. Functionally, the continuous paper strip “SC” is made by feeding a paper web that is double in width so that each connecting strip “F” separated by the continuous paper strip “SC” is double in width, suitable for connecting the tobacco segments “ST” and the double filter segment “SF” of each group of segments “GS”. Thereby, as will be more apparent in the continuation of the present invention, each rolled article “A” is double in length and has a pair of first graphic designs “M1 ” and a pair of second graphic designs “M2”.

The connecting strip forming unit 400 is preferably configured to work on a paper strip “SC”, which is pre-printed or pre-embossed, thus already provided with a succession of second graphic designs “M2” and it is devoid of an applicator unit (printing or embossing) intended to apply graphic designs on the web.

Whereas, according to a variant, not shown, the feed means 401 can comprise a printing device, operatively located upstream of the cutting and applicator device 402 and configured to make the second graphic designs “M2” on the continuous paper strip “SC”. Specifically, the printing device is provided with at least one printing plate, the operating position of which is adjustable at least in the direction longitudinal to the movement direction of the continuous paper strip “SC” so as to take a plurality of operating positions.

Independently of the presence of the printing device, the feed means 401 of the connecting strip forming unit 400 further comprise an eccentric roller 405, located upstream of the cutting and applicator device 402, and specifically, immediately upstream of the cutting and applicator device 402, and configured to alternately vary, in a cadenced manner, the feeding speed of an end portion of the continuous paper strip “SC” between a minimum value and a maximum value. Such eccentric roller 405, known for such application, has the function of converting a continuous unwinding movement of the paper strip “SC” upstream thereof into a discontinuous movement (substantially intermittent or nonetheless varying between a maximum speed and a minimum speed) of the end portion of the paper strip “SC” downstream thereof, specifically in the cutting and applicator device 402. This allows spacing the newly cut connecting strips, suitable for the application of the connecting strips on the groups “GS”.

The eccentric roller 405 is preferably movably mounted on a respective stationary support so as to be transversely adjusted on approaching/moving away from the feeding path of the continuous paper strip “SC” so as to take a plurality of operating positions.

The cutting and applicator device 402 of the connecting strip forming unit 400 comprises a dragging roller 406, configured to hold by suction and drag, on advancing, an end portion of the continuous paper strip “SC”, and a cutting roller 407, which is homokinetic with the dragging roller 406 and cooperating therewith to make a series of cuts on the continuous paper strip “SC” obtaining the aforesaid succession of connecting strips “F”.

Downstream of the connecting strip forming unit 400, the machine 1 comprises a rolling unit 500, of the known type, configured to roll each connecting strip “F” around the respective group of segments “GS” to obtain a rolled article “A”, having a first graphic design “M1 ” on each tobacco side and a second graphic design “M2” on each filter side.

The rolling unit 500 is preferably configured to make a succession of double rolled articles “A” and comprises, or is followed by, an auxiliary cutting device 501 configured to make a cut halfway along each double rolled article “A” so as to obtain a pair of single-length rolled articles “A”, each having a first graphic design “M1 ” on the tobacco side and a second graphic design “M2” on the filter side.

According to the invention, the machine 1 comprises at least one sensor 600 located at or downstream of the rolling unit 500 (upstream or downstream of the possible auxiliary cutting device 501 ) to detect the position and/or orientation of the first graphic design “M1 ” and the second graphic design “M2” on each rolled article “A”.

The sensor 600, preferably a video camera, specifically arranged facing a conveying drum for conveying the rolled articles “A”, is configured to acquire images of the rolled articles “A” with particular focus on the graphic designs “M1”, “M2”.

The machine 1 further comprises a control unit “U” connected to the at least one sensor 600 and configured to determine a position and/or orientation deviation between the first graphic design “M1 ” and the second graphic design “M2” of each rolled article “A”. Such deviation is preferably defined by an angular deviation between the position of the first graphic design “M1 ” and the position of the second graphic design “M2”. In other words, the deviation is given by the angle, around the axis of the rolled article “A”, between the radial plane on which the first graphic design “M1 ” extends and the radial plane on which the second graphic design “M2” extends (the radial plane being considered a radial plane passing through the longitudinal axis of the rolled article “A”).

Additionally, or alternatively, the deviation could be defined by an angle of inclination (absence of parallelism) between each graphic design “M1 ”, “M2” and a radial plane of reference passing through the longitudinal axis of the rolled article “A”.

According to the invention, the control unit “LT is further connected to the connecting strip forming unit 400 and is configured to adjust the connecting strip forming unit 400 as a function of the stated deviation detected.

The control unit “LT is preferably further connected to the tobacco segment forming unit 100 and is configured to further adjust the tobacco segment forming unit 100 and as a function of the stated deviation detected.

By analyzing the information acquired by the sensors, the control unit “LT determines a position deviation between the two graphic designs “M1 ”, “M2” with respect to a predetermined reference positioning of the two graphic designs “M1 ”, “M2” and/or an orientation deviation between the graphic designs “M1 ”, “M2” with respect to a predetermined reference orientation. As a function of such analysis, the control unit “U” can start the adjustment of the tobacco segment forming unit 100 and/or the connecting strip forming unit 400 to compensate such deviations.

According to an aspect of the present invention, the control unit “U” is configured to start the aforesaid adjustment when a trend in the position and orientation deviation is detected as exceeding a predetermined threshold and/or in a minimum percentage of rolled articles “A”. Specifically, the trend is determined by the evolution of the deviation on a predetermined number of consecutive rolled articles “A”.

In other words, the “U” control unit records the position and/or orientation deviation of the aforesaid succession of rolled articles “A”. If a consecutive number of rolled articles “A”, greater than the minimum number, has a position and/or orientation deviation greater than a threshold value, the control unit “LT adjusts the tobacco segment forming unit 100 and/or the connecting strip forming unit 400.

Whereas, if only a small number of consecutive rolled articles “A”, smaller than the minimum number, showed a position and/or orientation deviation greater than a threshold value, the control unit “LT does not adjust the tobacco segment forming unit 100 and/or the connecting strip forming unit 400, but it can provide a reject signal for the rolled articles “A” having such deviation.

Preferably, if the machine 1 is working on double rolled articles “A”, the position and/or orientation of the first graphic designs “M1 ” and of the second graphic designs “M2” relative to each double rolled article “A” can be detected by means of the at least one sensor 600, arranged upstream or downstream of the auxiliary cutting device 501. Therefore, the control unit “LT is configured to adjust the applicator device 110 and/or the connecting strip forming unit 400 as a function of a position and/or orientation deviation between the first and respective second graphic designs “M1 ”, “M2” relative to a same double rolled article “A”.

Whereas, if the machine 1 were working on single rolled articles “A”, the position and/or orientation of the first graphic designs “M1 ” and of the second graphic designs “M2” relative to each rolled article “A” can be detected by means of the at least one sensor 600, arranged downstream of the auxiliary cutting device 501 , where present. Therefore, the control unit “U” is configured to adjust the applicator device 110 and/or the connecting strip forming unit 400 as a function of a position and/or orientation deviation between the first and the second graphic design “M1 ”, “M2” relative to a same rolled article “A”.

Hereinafter, different adjustment methods of the machine 1 will now be described, implemented by the control unit “U” as a function of the aforesaid position and/or orientation deviation and according to the present invention.

According to a first adjustment method, the control unit “U” is configured to adjust the step of feeding the continuous paper strip “SC” and/or cutting the continuous paper strip “SC” as a function of the position and/or orientation deviation between the first and the second graphic design “M1 ”, “M2”, detected by the sensor 600. In other words, according to such method, the control unit “U” is configured to adjust the components of the connecting strip forming unit 400.

According to an example, the control unit “U” can be configured to adjust the unwinding apparatus 403 of the connecting strip forming unit 400. Specifically, the control unit “U” can be configured to adjust the unwinding speed and/or the angular step of the unwinding apparatus 403 (feed roll 404 or pulling rollers), as a function of the position and/or orientation deviation between the first and the second graphic design “M1 ”, “M2”.

According to a further example, the control unit “U” is configured to adjust the position and/or rotation of the eccentric roller 405 of the connecting strip forming unit 400. Specifically, the control unit “U” can be configured to adjust the angular speed and/or angular step of the eccentric roller 405, as a function of the position and/or orientation deviation between the first and the second graphic design “M1 ”, “M2”.

Alternatively, the control unit “U” is configured to adjust the operating position (transversely to the lying plane of the paper strip “SC”) of the eccentric roller 405 as a function of the position and/or orientation deviation between the first and the second graphic design “M1 ”, “M2”.

According to a further example, the control unit “U” is configured to adjust at least one of the dragging 406 and cutting 407 rollers of the connecting strip forming unit 400. Specifically, the control unit “U” can be configured to adjust the rotation speed and/or angular step of at least one of the dragging 406 and cutting 407 rollers as a function of the position and/or orientation deviation between the first and the second graphic design “M1”, “M2”.

According to a further example, when present, the control unit “U” is configured to modify the operating position of the printing plate of the connecting strip forming unit 400 as a function of the position and/or orientation deviation between the first and the second graphic design “M1”, “M2”.

In general, the control unit “LT can be configured to adjust only one of the aforesaid components of the connecting strip forming unit 400 or it can be configured to adjust a combination of two or more of the components of the connecting strip forming unit 400 as a function of the position and/or orientation deviation between the first and the second graphic design “M1 ”, “M2” so as to optimize the process.

According to an adjustment method, the control unit “U” is configured to adjust the application step of the first graphic designs “M1 ” as a function of the position and/or orientation deviation between the first and the second graphic design “M1 ”, “M2” by transversely adjusting the applicator device 110 of the tobacco segment forming unit 100. In other words, according to such method, the control unit “U” is configured to adjust the components of the tobacco segment forming unit 100.

According to further adjustment methods, the control unit “U” can be configured to simultaneously adjust one or more components of the connecting strip forming unit 400 and, simultaneously, the applicator device 110 of the tobacco segment forming unit 100.

A variant of the machine 1 , not shown, will now be described with particular reference to the tobacco segment forming unit 100 and to the combining unit 300.

In such embodiment, the tobacco segment forming unit 100 is configured as a double-line machine, to make two parallel successions of tobacco segments “ST”.

In detail, the paper feed line 102 is configured to feed at least two paper webs unwound from respective rolls 101 .

Alternatively, the paper feed line 102 is configured to feed a single paper web unwound from a respective roll 101 and the tobacco segment forming unit 100 comprises a longitudinal cutting device located on the paper feed line 102 for cutting the single paper web into at least two juxtaposed webs. Downstream of the paper feed line 102, independently of the origin of the two paper webs, the tobacco segment forming unit 100 comprises at least two forming beams 105 each configured to wrap a respective continuous stream of filling material with a respective one of the aforesaid paper webs and it has at least two applicator devices 110 for making respective successions of first graphic designs “M1 ” on each paper web.

The applicator devices 110 are preferably adjustable, independently of each other, at least along a direction transverse to the respective web, to independently adjust the lateral position of the first graphic designs “M1 ” on the respective paper webs.

When the longitudinal cutting device is present, the applicator devices 110 are preferably located upstream of the longitudinal cutting device.

According to such variant, the combining unit 300 is thus configured to receive two successions of tobacco segments “ST” moved transversely and combine such successions of tobacco segments “ST” with the succession of filter segments “SF” to form a succession of groups of segments “GS”, each comprising a double-length filter segment “SF” interposed between two tobacco segments “ST”.

Downstream of the combining unit 300, the machine 1 (and specifically the control unit “U”) acts according to the above description.

Specifically, again with reference to a double line machine, in the case of online printing of the second graphic designs “M2” on the paper strip “SC” from which the connecting strips “F” are obtained, the second graphic designs “M2” can be printed by means of respective printing plates, which are preferably independent of one another and independently controllable for separately managing the correct feedback application of the second graphic design “M2”. It is also conceivable that instead of a single paper strip “SC” bearing two second graphic designs “M2” two separate, juxtaposed paper strips can be fed, on each of which a respective printing plate works. Thus described, the invention lends itself to numerous variants falling within the same inventive concept.

For example, in case of printing or applying graphic designs in several steps, e.g. color printing, two or more plates can be provided in series for each graphic design, each for printing with a respective color. In this case, despite all being adjustable, such printing plates are preferably synchronously controlled, so as to make the same adjustment in position of the single prints, which are mutually aligned.

Furthermore, for example in the case of products other than traditional cigarettes and/or products having more than one wrapped connecting strip, the invention provides the application of the principle of alignment and adjustment to end products provided with three or more graphic designs, for example three graphic designs, one of which applied on the cigarette segment and two applied or pre-applied on respective paper strips from which the connecting strips to be rolled are obtained. It is almost irrelevant whether the graphic designs are applied online or preapplied (or some pre-applied and others applied online), as the invention extends to both cases.

The present invention achieves the set objects, overcoming the drawbacks of the prior art. The machine 1 thus described allows obtaining cigarettes “P”, having a first graphic design “M1 ” on the tobacco side “P1” and a second graphic design “M2” on the filter side “P2” and aligned with the first graphic design “M1 ”. The machine 1 thus described allows reducing systemic process errors so as to limit, if not reduce, the amount of cigarettes “P” discarded as a result of defects.

Such results are obtained, specifically by virtue of the control unit “U”, which, by cooperating with the at least one sensor 600, allows feedback adjustment of one or more of the components of machine 1 , thus as a function of the position and/or orientation deviation between the first graphic design “M1 ” and the second graphic design “M2” on the rolled articles “A”. The invention is equally applicable to rod-shaped articles of a different type, in which two graphic designs are made on different zones, processed at different times and/or in different areas of the same system and specifically, on a first web, successively wrapped in a tubular shape and on a succession of connecting strips, successively applied directly to the rod-shaped semi-finished product comprising the first graphic design.

Claims

1. A machine (1 ) for making cigarettes (P), having a first graphic design (M1 ) on the tobacco side (P1), and a second graphic design (M2) on the filter side (P2) and aligned with the first graphic design (M1 ), the machine (M1 ) comprising: a tobacco segment forming unit (100) configured to make a continuous rod (B) provided on the outside of it with a succession of first graphic designs (M1 ), to cut the continuous rod (B) into tobacco segments (ST), each having at least one graphic design (M1 ) on it, and to feed the tobacco segments (ST) in succession; a feed unit (200) for feeding a succession of filter segments (SF); a combining unit (300) configured to receive and combine the successions of tobacco segments (ST) and filter segments (SF) to form a succession of groups of segments (GS), each comprising at least one tobacco segment (ST) and one filter segment (SF) abutted end to end; a connecting strip forming unit (400) comprising feed means (401 ) configured to feed a continuous strip of paper (SC) having a succession of second graphic designs (M2) along a feed path, and a cutting and applicator device (402), located downstream of the feed means (401 ) and configured to cut the continuous paper strip (SC) transversely so as to make a succession of connecting strips (F), each having at least one respective second graphic design (M2) at a predetermined position, and to apply each connecting strip (F) on the outside surface of a respective group of segments (GS) coming from the combining unit (300); a rolling unit (500), configured to roll each connecting strip (F) around the respective group of segments (GS) to obtain a rolled article (A); the machine (1 ) further comprising at least one sensor (600), located at or downstream of the rolling unit (500) to detect the position and/or the orientation of the first graphic design (M1 ) and of the second graphic design (M2) on each rolled article (A), and a control unit (U) connected to the at least one sensor (600) and configured to adjust the connecting strip forming unit (400) as a function of a position and/or orientation deviation between the first graphic design (M1 ) and the second graphic design (M2).

2. The machine (1 ) according to claim 1 , wherein the feed means (401 ) of the connecting strip forming unit (400) comprise an unwinding apparatus (403) configured to unwind the continuous strip of paper (SC) in a controlled manner from a feed roll (404) and to feed the continuous strip of paper (SC) to the cutting and applicator device (402); and wherein the control unit (U) is configured to adjust the unwinding apparatus (403), specifically the unwinding speed and/or the angular phase, as a function of the position and/or orientation deviation between the first and the second graphic design (M1 , M2).

3. The machine (1 ) according to claim 2, wherein the connecting strip forming unit (400) is configured to operate on a pre-printed web provided with a succession of second graphic designs (M2) and does not have printing units for printing graphic designs on the web.

4. The machine (1 ) according to any one of the preceding claims, wherein the feed means (401 ) of the connecting strip forming unit (400) comprise an eccentric tensioning roller (405), located upstream of the cutting and applicator device (402), and more specifically, just upstream of the cutting and applicator device (402) and configured to vary between a minimum value and a maximum value and in an alternating and rhythmic manner, the feed speed of an end portion of the continuous strip of paper (SC); and wherein the control unit (U) is configured to adjust the position and/or the rotation of the eccentric roller (405), specifically the speed and/or the phase thereof, as a function of the position and/or orientation deviation between the first and the second graphic design (M1 , M2).

5. The machine (1 ) according to claim 4, wherein the eccentric roller (405) is movably mounted on a respective stationary support so it can be transversely adjusted towards/away from the movement path of the continuous strip of paper (SC) in order to adopt a plurality of operating positions; and wherein the control unit (U) is configured to adjust the operating position of the eccentric roller (405) as a function of the position and/or orientation deviation between the first and the second graphic design (M1 , M2).

6. The machine (1 ) according to any one of the preceding claims, wherein the cutting and applicator device (402) comprises an entrainment roller (406) configured to hold by suction and feed an end portion of the continuous strip of paper (SC), and a homokinetic cutting roller (407) moving at the same speed as the entrainment roller (406) and cooperating therewith to make a sequence of cuts on the continuous strip of paper (SC) to obtain a succession of connecting strips (F); and wherein the control unit (U) is configured to adjust at least one between the entrainment roller (406) and the cutting roller (407), specifically the rotation speed and/or the phase thereof, as a function of the position and/or orientation deviation between the first and the second graphic design (M1 , M2).

7. The machine (1 ) according to claim 1 , wherein the feed means (401 ) also comprise a printing device, operatively located upstream of the cutting and applicator device (402) and configured to make the second graphic designs (M2) on the continuous strip of paper (SC), the printing device being provided with a printing plate whose operating position can be adjusted longitudinally along the movement direction of the continuous strip of paper (SC) so as to be able to adopt a plurality of operating positions; and wherein the control unit (U) is configured to adjust the operating position of the printing plate as a function of the position and/or orientation deviation between the first and the second graphic design (M1 , M2).

8. The machine (1 ) according to any one of the preceding claims, wherein the sensor (600) is a camera, specifically arranged to face a conveying drum which transports the rolled articles (A).

9. The machine (1 ) according to any one of the preceding claims, wherein the control unit (U) is configured to start the adjustment when a trend in the position and/or orientation deviation is detected as exceeding a predetermined threshold and/or in a minimum percentage of rolled articles (A), specifically such trend being determined as the deviation in a predetermined number of consecutive rolled articles (A).

10. The machine (1 ) according to any one of the preceding claims, wherein: the tobacco segment forming unit (100) is configured to make doublelength tobacco segments (ST), each having a pair of first graphic designs (M1 ) on its outside surface; the filter segment feed unit (200) is configured to feed double-length filter segments (SF); the combining unit (300) is configured to make a transverse cut half way along each of the double-length tobacco segments (ST) so as to obtain a pair of single-length tobacco segments (ST), to axially spread the singlelength tobacco segments (ST) apart from each other and to insert a respective double-length filter segment (SF) between two tobacco segments (ST) that have been spread apart, so as to feed a succession of double segment groups (GS), each made up of two tobacco segments (ST) separated by a double-length filter segment (SF); the connecting strip forming unit (400) is configured to make double connecting strips (F), each having a pair of second graphic designs (M2) arranged mirror symmetrically to each other and to apply the double connecting strip (F) on the outside surface of each double segment group (GS) coming from the combining unit (300); the rolling unit (500) is configured to make a succession of double rolled articles (A) and comprises, or is followed by, an auxiliary cutting device (501 ) configured to make a cut half way along each double rolled article (A) to obtain a pair of single-length rolled articles (A), each having a first graphic design (M1 ) on the tobacco side (P1), and a second graphic design (M2) on the filter side (P2); wherein the position and/or orientation of the first graphic designs (M1 ) and of the second graphic designs (M2) of each double rolled article (A) are detected by the at least one sensor (600), located upstream or downstream of the auxiliary cutting device (501 ), and wherein the control unit (U) is configured to adjust the connecting strip forming unit (400) as a function of a position and/or orientation deviation between the first and the respective second graphic designs (M1 , M2) of a single double rolled article (A).

11. A method for making cigarettes (P), having a first graphic design (M1 ) on the tobacco side (P1 ), and a second graphic design (M2) on the filter side (P2) and aligned with the first graphic design (M1 ), the method being, in particular, implemented by a machine (1 ) according to any one of the preceding claims; the method comprising the steps of: forming a succession of tobacco segments (ST) by making a continuous rod (B) provided on the outside of it with a succession of first graphic designs (M1 ), and cutting the continuous rod (B) into tobacco segments (ST), each having at least one graphic design (M1 ) on it; combining the successions of tobacco segments (ST) with respective filter segments (SF) to form a succession of groups of segments (GS), each comprising at least one tobacco segment (ST) and one filter segment (SF) abutted end to end; feeding a continuous strip of paper (SC) along a feed path via feed means (401 ), the continuous strip of paper (SC) having a plurality of second graphic designs (M2), longitudinally equispaced along the continuous strip of paper (SC); cutting the continuous strip of paper (SC) via a cutting and applicator device (402) so as to obtain a succession of connecting strips (F), each provided with at least one of the second graphic designs (M2); applying each connecting strip (F) to a respective group of segments (GS); rolling each connecting strip (F) around the respective group of segments (GS) to create a stable connection between the segments of each group to obtain a succession of rolled articles (A); via a sensor (600), detecting the position and/or the orientation of the first graphic design (M1 ) and of the second graphic design (M2) on each rolled article (A); adjusting the step of feeding the continuous strip of paper (SC) and/or cutting the continuous strip of paper (SC) as a function of a position and/or orientation deviation between the first and the second graphic design (M1 , M2) detected by the sensor (600); the step of applying being carried out by feedback control through a control unit (U) connected to the sensor (600) and to the feed means (401 ) and/or to the cutting and applicator device

(402).

12. The method according to claim 11 , wherein the step of feeding the continuous strip of paper (SC) is accomplished by unwinding the strip from a roll (404) via an unwinding apparatus (403) and wherein the step of adjusting the step of feeding the continuous strip of paper (SC) is carried out by adjusting the unwinding apparatus (403), specifically the unwinding speed and/or the angular phase, as a function of the position and/or orientation deviation between the first and the second graphic design (M1 , M2).

13. The method according to claim 11 or 12, wherein the step of feeding the continuous strip of paper (SC) comprises a step of varying between a minimum value and a maximum value and in an alternating and rhythmic manner, the feed speed of an end portion of the continuous strip of paper (SC) via an eccentric roller (405) located upstream of the end portion of the continuous strip of paper (SC), and wherein the step of adjusting the step of feeding the continuous strip of paper (SC) is carried out by adjusting the position and/or the rotation of the eccentric roller (405), specifically the speed and/or the phase thereof, as a function of the position and/or orientation deviation between the first and the second graphic design (M1 , M2).

14. The method according to any one of claims 11 to 13, wherein the step of adjusting the step of cutting the continuous strip of paper (SC) is carried out by adjusting the cutting and applicator device (402), specifically the speed and/or the phase thereof, as a function of the position and/or orientation deviation between the first and the second graphic design.

15. The method according to claim 14, comprising, via the control unit (U), a step of monitoring a trend in the position and/or orientation deviation between the first and the respective second graphic design (M1 , M2), specifically such trend being determined as the deviation detected in a predetermined number of consecutive articles, and wherein the step of adjusting the step of feeding and/or cutting being started when the trend exceeds a predetermined threshold and/or is present in a minimum percentage of rolled articles (A).

16. The method according to any one of claims 11 to 15, wherein: the step of forming a succession of tobacco segments (ST) being carried out by forming double-length tobacco segments (ST), each having a pair of first graphic designs (M1 ) on its outside surface, aligned with each other in axial direction; the step of combining the tobacco segments (ST) with the filter segments (SF) is carried out by making a transverse cut half way along each of the double-length tobacco segments (ST) so as to obtain a pair of singlelength tobacco segments (ST), axially spreading the single-length tobacco segments (ST) apart from each other and inserting a respective doublelength filter segment (SF) between two tobacco segments (ST) that have been spread apart, so as to obtain a succession of double segment groups (GS), each comprising two tobacco segments (ST) separated by a double filter segment (SF); the step of feeding the continuous strip of paper (SC) is carried out by feeding a continuous paper strip (SC) that is double in width so that each connecting strip (F) separated by the strip has a double width suitable for connecting the tobacco segments (ST) and the double filter segment (SF) of each group of segments (GS), each rolled article (A) thus having double length and being provided with a pair of first graphic designs (M1 ) and a pair of second graphic designs (M2); the step of rolling is followed by a step of making a cut half way along each double rolled article (A) to obtain a pair of single-length rolled articles (A), each having a first graphic design (M1 ) on the tobacco side (P1), and a second graphic design (M2) on the filter side (P2); wherein the position and/or orientation of the first graphic designs (M1 ) and of the second graphic designs (M2) of each double rolled article (A) are detected by the at least one sensor (600), located upstream or downstream of the cut made half way along the double rolled articles (A), and wherein the step of feeding the continuous strip of paper (SC) and/or of cutting the continuous strip of paper (SC) is carried out as a function of a position and/or orientation deviation between the first and the respective second graphic designs (M1 , M2) of a single double rolled article (A).

17. The method according to any one of claims 11 to 16, wherein in the step of feeding a continuous strip of paper (SC) having a plurality of second graphic designs (M2) which are longitudinally equispaced along the continuous strip of paper (SC), the continuous strip of paper (SC) is unwound from a roll (404) and is provided with the second graphic designs (M2) pre-applied thereon.