DESCRIPTION

The present invention relates to a labelling machine for applying labels onto receptacles.

The present invention also relates to a method for applying labels onto receptacles.

Different technologies are known for applying labels onto a succession of receptacles, such as bottles, containers or the like.

One of these technologies provides for advancing a web of labelling material, cutting the web to obtain single labels and the application of the labels thus obtained onto respective receptacles during of the receptacles along a predetermined conveying path and during a rotation of these receptacles about their longitudinal axes. These labels are known as roll-fed labels.

Application of the labels according to this technology is obtained through the use of automatic labelling machines.

A typical labelling machine of the so-called roll feed type comprises:

- a conveying apparatus (for example a carousel or a conveyer belt) for conveying the receptacles along a respective conveying path; and

- a labelling apparatus for applying at least one label onto each receptacle during conveying of the receptacles along at least one portion of the conveying path.

The labelling apparatus comprises:

- a first conveyor for advancing a web of labelling material along a first advancement path;

- a cutting unit for cutting the web of labelling material into single labels at a cutting station; and

- a second conveyor configured to advance the single labels from the cutting station to at least one application station, at which the single labels are applied to respective receptacles .

It is known that the web of labelling material has a repetition (in succession) of a decorative pattern defined by unitary decorations.

In use, advancement of the web of labelling material carried out by the first conveyor and cutting of the web of labelling material carried out by the cutting unit must be coordinated such that each of the single labels has the respective decorative pattern. In the case of an incorrect cutting, the labels obtained by the cutting unit have portions of the decorative patterns of the respective adjacent repetitions resulting in the single label being incorrect, as their application to the respective receptacles means that these receptacles must be discarded.

Moreover, there are situations, for example after the splicing of a new web of labelling material to the web of labelling material in use or insertion of a new type and/or format of web of labelling material, that require a relative positioning of the web of labelling material to obtain correct synchronisation of the treatments of the web of labelling material.

Moreover, besides cutting of the web of labelling material, further treatments of the web of labelling material are known, for example printing data (for example relating to an expiry date and/or the production batch and/or the production site) on predetermined portions of the web of labelling material.

Therefore, it is evident that it is necessary to know, with sufficient precision, the position of the web of labelling material, in particular the repetitions of the decorative patterns and/or of the respective unitary decorations, during advancement of the web of labelling material along the first advancement path.

To this end, perfect synchronisation, for example obtained during the calibration and adjustment step of the labelling machine, for example between the first conveyor, the second conveyor and the cutting unit, may not suffice, as during operation unavoidable irregularities can occur; for example, the web of labelling material can be printed irregularly, or can undergo lengthening or shortening following tensile forces exerted on the web of labelling material during conveying thereof, giving rise to errors during operation, such as cutting, printing or splicing.

For this reason, the use of monitoring devices has been proposed to determine the length of the labels during the operation of the labelling machine, so as to recover information relating to any irregularities.

These monitoring devices provide for the use of suitable signs, or marks, positioned at desired regions of the web of labelling material, for example at the end and/or at the start of a respective label. Typically, these monitoring devices provide for the use of suitable sensors adapted to identify the aforesaid signs or marks and to send suitable signals to a control unit of the labelling machine, so as to carry out the cutting operations (or other types of operations on each unitary decoration) correctly.

However, these known systems have some drawbacks.

Firstly, the decorative patterns reproduced on the web of labelling material may be confused with the marks that must be read by the optoelectronic sensors, thereby causing incorrect reading by these sensors, and consequently errors in determining the length of the related labels.

Moreover, for aesthetic reasons the aforesaid signs or marks must preferably be concealed, after the final product has been produced. For example, the portion of the cut label bearing the sign or mark must be covered by overlapping of the opposite end of the label (in the case in which the label is wound around a related container) , so that after being affixed to the container it is not visible. Consequently, the label must be longer than effectively required, causing an increase in consumption of material and in production costs. In the case of the use of transparent, or partially transparent labels, it is not possible to cover the sign or mark, which hence remains visible on the final product.

Therefore, in the branch there is the need for improving of labelling machines, in particular to overcome at least one of the aforesaid drawbacks.

Moreover, in the branch there is a need to improve methods of labelling, in particular to overcome at least one of the aforesaid drawbacks.

The object of the present invention is to provide a labelling machine and a method for labelling, which allow to overcome in a simple and economical manner at least one of the aforesaid drawbacks.

The aforesaid objects are achieved by the present invention, as it relates to a labelling machine and to a method for labelling receptacles as defined in the independent claims.

Alternative preferred embodiments of the present invention are protected in the dependent claims.

For a better understanding of the present invention, a preferred embodiment is described below, purely by way of a non-limiting example and with reference to the accompanying drawings, wherein:

- Fig. 1 is a schematic and partial top view of a labelling machine, with parts removed for clarity;

- Fig. 2 is a simplified front view of a portion of a web of labelling material, with parts removed for clarity;

- Figs. 3A-3C show continuously acquired images of a web of labelling material by a component of the labelling machine of Fig. 1, with parts removed for clarity; and

- Fig. 4 schematically shows a detail of a portion of the labelling machine of Fig. 1 containing information relating to a plurality of reference images.

With reference to Fig. 1, a labelling machine for applying labels 2 to a succession of receptacles, such as bottles 3, containers or the like, is indicated as a whole with numeral 1.

The following description shall refer, without any limitation, to a labelling machine 1 adapted to apply labels 2 to receptacles that can be filled or are filled with a pourable product, in particular a pourable food product, such as carbonated liquids (sparkling water, non-alcoholic beverages, beer, etc.), non-carbonated liquids (still water, fruit juices, wine, etc.), emulsions, suspensions, high viscosity liquids and beverages containing pulp. Moreover the following description shall refer without limitation, to bottles 3, in particular made of a thermoplastic polymer, such as polyethylene terephthalate . However, the bottles 3 could also be made of a different material, such as glass, aluminium, etc.

With particular reference to Fig. 1, labelling machine 1 comprises a labelling apparatus 4 for applying at least one label 2 to each bottle 3 at an application station 5 during conveyment of bottles 3 along at least one active portion PI of a conveying path P.

Preferably but not necessarily, labelling machine 1 further comprises a conveying apparatus for conveying bottles 3 along conveying path P, in particular through application station 5.

In the non-limiting case illustrated, the conveying apparatus comprises a carousel 6 configured to advance bottles 3 along conveying path P, in particular having a curved shape .

In an alternative embodiment not illustrated, the conveying apparatus could comprise a conveyor belt.

In more detail, carousel 6 is adapted to rotate about a respective rotation axis A and comprises a plurality of retaining units (not illustrated and known per se) arranged at a peripheral portion of carousel 6 itself. The retaining units are arranged equally spaced from one another around rotation axis A of carousel 6 and each is adapted to retain a respective bottle 3 during conveyment of bottle 3 along conveying path P. Moreover, each retaining unit is configured at least to allow and/or determine a rotation of the respective bottle 3 about the respective longitudinal axis during the application of the respective label 2.

With particular reference to Fig. 1, labelling apparatus 4 comprises:

a first conveyor 10 for advancing a web 11 of labelling material along a first advancement path Q;

- a cutting unit 12 configured to cut web 11 at a cutting station 13 so as to obtain the single labels 2; and

- a second conveyor 14 configured to advance the single labels 2 along at least one portion of a second advancement path R, in particular from cutting station 13 to at least application station 5.

It should be noted that web 11 comprises a repetition (in succession) of a decorative pattern 15, in which each repetition substantially corresponds to the (longitudinal) extension of a singlelabel 2.

In particular, each decorative pattern 15 comprises a plurality of unitary decorations 16. Preferably, the respective decorative patterns 15 of the repetitions are substantially identical and in particular the decorative patterns 15 of the repetitions differ from one another at most only in some portions. For example, the decorative patterns 15 can comprise information relating to the production data and/or time, to the batch number or the like, in particular information that can be applied in an online procedure .

It should be noted that, in use, web 11 must be cut so that each label 2 comprises a single decorative pattern 15 (and that label 2 has a desired longitudinal length defined substantially by this decorative pattern 15) . In other words, web 11 must be cut at respective cutting lines (each decorative pattern 15 is interposed between two respective cutting lines) .

In a preferred non-limiting embodiment, web 11 is made of polymeric material or of paper material.

It should be noted that decorative pattern 15, in particular unitary decorations 16, are specific for a particular label type and/or format. In particular, a first web 11 for labels of a label type and/or format has a repetition of decorative patterns 15, said decorative patterns 15 differing from those of a second web 11 for labels of another label type and/or format.

With particular reference to Fig. 1, labelling machine 1, in particular labelling apparatus 4, further comprises:

- a control unit 17 configured to control labelling machine 1, in particular labelling apparatus 4; and - a determination device 19 configured to determine and/or detect a relative positioning, and preferably but not necessarily, also an extension, of each repetition of decorative pattern 15 and to generate a reference signal relating to the relative positioning, in particular relating to a reference station, of each repetition of decorative pattern 15.

Preferably but not necessarily, labelling apparatus 4 also comprises a glue application unit 22 configured to apply glue to at least one portion of labels 2 and/or of bottles

3.

In a preferred non-limiting embodiment, labelling apparatus 4 also comprises a storage unit configured to receive and contain web 11, in particular at least one reel 24 on which web 11 is wound. In particular, reel 24 rotates about a rotation axis B to allow unwinding of the web 11.

In a preferred non-limiting embodiment, labelling apparatus 4 also comprises a buffer unit 25 arranged downstream of the storage unit along first path Q to avoid excessive tensioning of web 11 during its advancement.

In more detail and with particular reference to Fig. 1, first conveyor 10 comprises:

- at least one feed roller 26 configured to rotate about an axis C, in particular having a vertical orientation, and configured to at least partially control the advancement and/or the advancement speed of web 11;

- preferably but not necessarily, an electric motor (not illustrated) to drive the rotation of advancement roller

26 around axis C (and having its own rotation axis) ;

- preferably but not necessarily, a position sensor (not illustrated) , for example an encoder, in particular associated with the electric motor, and configured to provide information relating to the advancement of web 11 with respect to advanementroller 26; and

- preferably but not necessarily, an auxiliary roller

27 arranged adjacent, in particular tangential, to advancement roller 26 to interpose, in use, web 11 between auxiliary roller 27 and advancement roller 26 to prevent slippage of web 11.

In a preferred non-limiting embodiment, first conveyor 10 further comprises a plurality of sliding rollers (not specifically illustrated) , in particular passive, to at least partially guide advancement of web 11.

Preferably but not necessarily, first conveyor 10 also comprises an auxiliary conveying unit, in particular an auxiliary drum 28 rotating about an axis E, configured to advance web 11 along a final portion of path Q and, in particular, to support the transfer of single labels 2 to second conveyor 14. In particular, auxiliary drum 28 is arranged downstream of advancement roller 26 and adjacent to second conveyor 14.

With particular reference to Fig. 1, in the specific case illustrated, cutting unit 12 is configured to cut web 11 in a manner defined "in contact". In particular, cutting unit 12 comprises at least one blade 29 and, preferably, at least one counter-blade 30, in particular configured to cut web 11 in mutual cooperation.

In an alternative embodiment, not illustrated, cutting unit 12 could be configured to cut web 11 in a manner defined "contactless", for example cutting unit 12 could comprise a laser .

With particular reference to Fig. 1, second conveyor 14 comprises a conveyor drum 31 rotating about an axis F and is configured to retain, in particular through suction, labels 2 during their advancement along at least one portion of path R.

In a preferred non-limiting embodiment, control unit 17 is configured to control, at least as a function of the reference signal and at least partially, cutting of web 11, in particular operation of cutting unit 12 and/or of first conveyor 10, in particular of advancement roller 26, so to correctly perform the cutting operations of web 11, in particular to ensure that each label 2 has a respective decorative pattern 15 (and the desired extension; i.e., the desired longitudinal length) . Preferably but not necessarily, control unit 17 is also configured to control cutting of web 11 as a function of the advancement position of web 11 with respect to advancement roller 26 and/or of an advancementspeed of web 11.

In a preferred non-limiting embodiment, control unit 17 is also configured to position, in particular as a function of the reference signal and/or of a signal of the position sensor, web 11 in relation to the reference station at least through control of first conveyor 10, in particular of advancement roller 26, more in particular through control of the rotation speed of advancement roller 26.

According to a preferred embodiment, control unit 17 is operatively connected to cutting unit 12 and/or to first conveyor 10.

Preferably but not necessarily, control unit 17 can comprise a PLC ("Programmable Logic Controller") and/or a microprocessor and/or a microcontroller.

In a preferred non-limiting embodiment, the reference station is defined by cutting unit 12 and is more specifically arranged at cutting station 13. Alternatively, the reference station can be defined by determination device 19 or by any other reference element.

With particular reference to Fig. 1, determination device 19 is operatively coupled to control unit 17 so as to allow, in particular through the reference signal, coordination between the relative positioning of the repetitions of decorative pattern 15 and cutting of web 11, in particular operation of cutting unit 12 and/or of first conveyor 10, in particular of advancement roller 26.

It should be noted that the information concerning the relative positioning of the repetitions of decorative pattern 15 makes it possible to determine and/or detect and/or calculate the relative positioning and/or the respective point in time of the cut by cutting unit 12 in relation to the respective repetitions of decorative pattern 15. In particular, determination device 19 is configured to ensure that control unit 17 controls cutting of web 11 by cutting unit 12 to obtain labels 2 having the respective decorative patterns 15 and, in particular also the desired extension (i.e., a longitudinal length of the label 2 that corresponds to the longitudinal length at least according to given margins) .

Advantageously, determination device 19 comprises:

- a visual system, in particular comprising a video camera 36, configured to capture, in particular continuously, acquired images 37 (see Figs. 3A-3C) of web 11, in particular during advancement of web 11 along advancement path Q and, even more in particular also at a monitoring station 38 arranged upstream of cutting station

13 along advancement path Q; and - a processing unit 39 operatively connected to the visual system, in particular to video camera 36, and configured to receive, in particular continuously, acquired images 37, to compare said acquired images 37 with at least one reference image 40 (of a respective decorative pattern 15) to determine at least the relative positioning of the repetitions of the decorative pattern 15 and/or of unitary decorations 16 and to generate the reference signal containing information concerning the relative positioning.

With particular reference to Figs. 3A to 3C, the visual system, in particular the camcorder 36, is configured to capture the acquired images 37 according to a given frame rate .

Non-limiting examples of acquired images 37 are illustrated in Figs. 3A to 3C which, in use, reflect different portions of decorative pattern 15 and/or of unitary decorations 16 as a function of the time and in various distributions (as a result of advancement of web 11) .

With particular reference to Fig. 4, reference image 40 comprises the respective decorative pattern 15 and/or one or more of the respective unitary decorations 16, in particular corresponding to and/or characterising of the label type and/or format of the respective label 2. In other words, each reference image 40 (of a respective decorative pattern

15) relates to a respective label type and/or format (in particular, which can be processed by labelling machine 1) .

In particular, it should be underlined that reference image 40 does not require to have all the details of the specific decorative pattern 15 of a respective label type and/or format of label, but only needs to have a portion of this decorative pattern 15, i.e., only one or more of the respective unitary decorations 16. However, with a larger amount of information encoded in the reference image or images 40 (i.e., with the presence of several, or possibly all, of the unitary decorations 16) it is possible to increase the quality and/or the precision of determination and/or detection of the relative positioning of the repetitions of the decorative pattern 15 and/or distinguish between a larger number of label types and/or formats of labels 2. However, it should also be noted that with the presence of fewer unitary decorations 16 on the reference images 40 it is possible to increase the processing speed.

In a preferred non-limiting embodiment, processing unit 39 is configured to determine, for each repetition of decorative pattern 15, through comparison between said acquired images 37 and the at least one reference image 40, a respective first cutting line (virtual) and a respective second cutting line (virtual) , in particular distinct from the first cutting line, of web 11, indicative of the relative positioning . Moreover processing unit 39 is also configured to generate the reference signal having information relating to the respective first cutting lines and to the respective second cutting lines for each repetition of decorative pattern 15.

It should be noted that the information relating to the respective first cutting lines and to the respective second cutting lines can be encoded directly, but also in terms of points in time of the cutting.

In particular, each decorative pattern 15 of a respective repetition is interposed between the respective first cutting line and the respective second cutting line. Preferably but not necessarily, the second cutting line of a respective repetition of decorative pattern 15 corresponds to the first cutting line of the subsequent repetition.

According to this preferred non-limiting embodiment, control unit 17 is configured to control first conveyor 10, in particular advancement roller 26, and/or cutting unit 12 so as to cut web 11 at the respective first cutting lines and the respective second cutting lines. In this way, labels 2 are obtained each having a respective decorative pattern 15.

Preferably but not necessarily, processing unit 39 is configured to compare acquired images 37 with the reference image or images 40 through a specific analysis algorithm. In particular, processing unit 39 is configured to compare and determine and/or detect a coincidence between respective decorative pattern 15 and/or one or more of the respective unitary decorations 16 of the reference image or images 40 and the decorative pattern present and/or the unitary decorations present in acquired images 37. With reference to the examples of Figs. 3A to 3C, it should be noted that processing unit 39 determines a coincidence with acquired image 37 shown in Fig. 3C. The other acquired images 37 of Figs. 3A and 3B have at least parts of the respective unitary decorations 16, but in a different order from that of the respective decorative pattern 15.

Preferably but not necessarily, processing unit 39 is configured to correlate this information with the information relating to the advancement of web 11 in relation to advancement roller 26, in particular provided by the position sensor, and/or the advancement speed of web 11.

In a preferred non-limiting embodiment, processing unit 39 is also configured to determine from at least one of the acquired images 37 the respective label type and/or format of the respective label 2, in particular through comparison (in the same way as described above) between acquired images 37 and at least one reference image 40, preferably through comparison with a plurality of reference images 40 (see Fig. 4) . According to a preferred non-limiting embodiment, labelling machine 1, in particular labelling apparatus 4, even more in particular determination device 19, further comprises a memory unit 41, in particular of non-volatile type, configured to contain, in particular containing, the plurality of reference images 40 of respective decorative patterns 15.

In particular, processing unit 39 and memory unit 41 are operatively connected to one another.

Preferably but not necessarily, processing unit 39 is configured to recover reference images 40 from memory unit 41.

According to a preferred but not necessary, embodiment, memory unit 41 is configured so that reference images 40 are stored in memory unit 41 before operation of the labelling machine 1.

Preferably but not necessarily, memory unit 41 is configured so that reference images 40 stored originate from an acquisition step carried out outside fromlabelling machine 1.

In use, labelling machine 1 applies labels 2 to bottles

3.

In particular, conveying apparatus 6 advances bottles 2 along path P and labelling apparatus 4 applies labels 2 to bottles 3 at application station 5. In more detail operation of labelling machine 1 comprises the following steps:

- advancing web 11 along path Q;

- cutting web 11 at cutting station 13 to obtain single labels 2;

- advancing single labels 2 from cutting station 13 to at least application station 5;

- applying single labels 2 at application station 5 to respective bottles 3;

determining and/or detecting the relative positioning, and in particular also the extension, of each repetition of decorative pattern 15;

generating the reference signal relating to the relative positioning of each repetition of decorative pattern 15; and

- controlling cutting of web 11 as a function of the reference signal.

In more detail, during the step of advanciong the web, web 11 is conveyed by first conveyor 10 along advancement path Q.

Preferably but not necessarily, the advancement, in particular the advancement speed, of web 11 is controlled at least partially by advancement roller 26, in particular the advancement speed of web 11 is determined at least partially by the rotation speed about rotation axis C. In more detail, during the step of advancing of the single labels 2, labels 2 are fed by second conveyor 14. In particular, single labels 2 are advancement by conveyor drum 31, which rotates about axis F.

Advantageously, the step of determining and/or detecting comprises at least the following sub-steps:

- capturing (continuously) , in particular through the visual system, even more in particular through video camera 36, acquired images 37;

comparing acquired images 37 with at least one reference image 40 for determining at least the relative positioning of the repetitions of decorative pattern 15 in relation to the reference station.

In more detail, during the step of controlling, control unit 17 controls cutting unit 12 and/or first conveyor 10, in particular advancement roller 26, as a function of the reference signal, and preferably but not necessarily, also as a function of the advancement speed of web 11 and/or of the advancement position of web 11.

In more detail, during the step of capturing, acquired images 37 are captured with a given frame rate.

In more detail, during the step of comparing, acquired images 37 are received from processing unit 39.

Preferably but not necessarily, processing unit 39 compares in particular through a specific analysis algorithm, acquired images 37 with one or more reference images 40 and determines and/or detects acquired images 37 that correspond to decorative pattern 15 and/or to the respective unitary decorations 16 reproduced (encoded) in the reference image 40.

For example, with reference to Figs. 3 and 4, the acquired image of Fig. 3C corresponds to the reference image 40 that is represented schematically in the upper right corner of Fig. 4.

In this way it is possible to determine the positioning in relation to the reference station, in particular cutting station 13.

In a preferred non-limiting embodiment, the determining and/or detecting step further comprises a processing sub step during which the respective first cutting line and the respective second cutting line of web 11 indicative of the relative positioning of the respective repetition of the decorative pattern 15 are calculated and/or obtained, in particular from comparison between acquired images 37 and the reference image or images 40, for each repetition of decorative pattern 15.

Preferably but not necessarily, during the generation sub-step, the reference signal is generated so as to contain (direct or indirect) information relating to the respective first cutting lines and to the respective second cutting lines; and during the step of controlling, cutting of web 11 is carried out at the respective first cutting lines and the respective second cutting lines.

According to a preferred embodiment, the determining and/or detecting step further comprises a sub-step of analysing the label type and/or the format, during which the respective label type and/or format of the label is determined, from at least one of the acquired images 37.

In particular, during the analysis sub-step, acquired images 37 are compared, in particular by processing unit 39, with reference images 40 for identifying the respective reference image 40 that corresponds to decorative pattern 15 and/or to the unitary decorations 16 reproduced on web 11.

According to a preferred embodiment, during the comparison sub-step and/or during the analysis sub-step, the reference image and/or images 40 is/are obtained from memory unit 41.

Preferably but not necessarily, the reference images 40 are stored in memory unit 41 during a storage step.

In particular, the storage step is carried out before the steps of feeding web 11, cutting web 11, feeding single labels 2 and determining and/or detecting the relative positioning .

Even more in particular, reference images 40 that are stored in memory unit 41 are from an acquisition step carried out outside labelling machine 1.

Preferably but not necessarily, the storage step and/or the acquisition step is/are carried out by a technician.

In a preferred non-limiting embodiment, control unit 17 controls the rotation of advancement roller 26, in particular the respective rotation speed, to position web 11 in relation to the reference station, in particular to cutting station 13.

In this way it is possible to coordinate the operation of cutting unit 12 and the advancement of web 11 to ensure correct cutting of web 11.

By examining the characteristics of labelling machine 1 and of the respective labelling method produced according to the present invention the advantages that can be obtained are evident .

In particular, through determination device 19 it is possible to determine, by comparison between acquired images 37 and reference images 40, the relative positioning of each repetition of the decorative pattern 15, thereby allowing an accurate control of the cutting step and/or of the advancement step of web 11. In this way it is possible to obtain labels 2, each having the respective decorative pattern 15. All this is possible without the need for signs and/or marks applied onto web 11 to indicate the extension of labels 2. Another advantage lies in the fact that determination device 19 allows to determine the label type and/or the format of the labels by comparison between acquired images 37 and reference images 40 stored in memory unit 41.

A further advantage is that the operation of the labelling machine 1 does not require a learning step, during which labelling machine 1 "learns" the decorative patterns 15 of the various label types and/or formats that can be processed by labelling machine 1. The reference images 40 are determined independently by labelling machine 1.

Finally, it is clear that modifications and variations of labelling machine 1 and the labelling method described and illustrated herein can be made without departing from the scope of protection defined by the claims.

In an embodiment, not illustrated, web 11 could be a web of labelling material of the heat-shrink type.