WO2020156785A1

WO2020156785A1 - Glue application device for a labeling unit

Info

Publication number: WO2020156785A1
Application number: PCT/EP2020/050648
Authority: WO
Inventors: Stefano Corradini; Cristian ANDREATO
Original assignee: Sidel Participations SAS
Current assignee: Sidel Participations SAS
Priority date: 2019-01-29
Filing date: 2020-01-13
Publication date: 2020-08-06
Anticipated expiration: 2021-07-29

Abstract

The invention refers to a glue application device (11, 11') configured to apply glue on labeling material (2, 3) intended for application on receptacles (4); the device (11, 11') comprises a glue roller (12, 12') rotatable around an own longitudinal axis (Y) and having an outer lateral surface (13, 13') configured to receive and transfer the glue; the outer lateral surface (13, 13') comprises a plurality of recesses (20, 20'), each having: a major axis (M); a minor axis (N) intersecting the major axis (M); and two opposite sides (21) defining respective arcs of a circumference, intersecting the minor axis (N) in the area of own respective intermediate portions (21a) and intersecting each other and said major axis (M) in the area of the respective ends (21b) thereof.

Description

TITLE: "GLUE APPLICATION DEVICE FOR A LABELING UNIT"

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TECHNICAL FIELD

The present invention concerns a glue application device for a labeling unit configured to apply glue on labeling material, in particular on labels prior to their application on receptacles, for example containers, bottles, cans or similar, in particular receptacles configured to contain a pourable product, preferably a pourable food product .

STATE OF THE ART

The bottling of pourable food or non-food products into respective receptacles is usually accompanied by the labeling of said receptacles with respective labels, in the form of thin bands obtained from a strip of labeling material, during a labeling process.

In particular, the labels perform the dual function of :

- communicating the respective brand of the bottled product and, therefore, attracting the attention of the end consumer once the product has been delivered and displayed; and

- providing the end consumer with important information on the content of the receptacle.

The general appearance of the label is therefore very important, hence the quality of the labeling process must guarantee a correct, repeatable and clean application of the label on the respective article, otherwise the latter will be discarded, with consequent increase in overall production costs.

Generally, the receptacles are labeled before, during or after filling, by means of specific labeling units.

Labeling units configured to prepare, transport and apply labels on respective receptacles configured to be filled with a pourable product are known.

The use of "glued labels", obtained from a strip of labeling material wound on one or more storage reels, is particularly widespread.

In particular, the strip of labeling material is cut in portions of equal size, to which glue is applied.

This type of labeling process is known as "roll-feed" labeling process.

In detail, according to said process, a sequence of receptacles is fed forward, along a predefined feed path, towards a labeling apparatus, for example a labeling module of the labeling unit configured to label each receptacle.

Inside the labeling module, the strip of labeling material is firstly fed from the respective storage reel, along a predefined feed path, to a cutting device, typically a knife, configured to separate the strip into a sequence of single labels having the same length. The labels thus obtained are then transferred and glued onto the outer lateral surface of respective articles.

The labeling module comprises a transfer device for transferring the labels, typically a vacuum drum configured to receive each label, retain it on an outer lateral surface thereof by means of suction, and apply said label to a respective receptacle, at an application station.

Before application on the respective receptacle, each label is spread with a layer of glue at an own inner side, or own back, that is the side configured to cooperate in contact, in particular to be rested, on the respective receptacle after application.

In this regard, the known labeling units are provided with a glue application device, usually carried by the labeling module and comprising:

- a glue roller, rotatable around an axis thereof and configured to apply the layer of glue from an outer lateral surface thereof on the back of the label to be applied;

- a glue feed circuit configured to continuously feed the glue to the glue roller, in particular towards the outer lateral surface of the glue roller, drawing from a glue storage tank; and

- a glue distribution element, in particular a scraper element defined typically by a bar or a blade arranged peripherally to the glue roller, configured to receive the glue from the feed circuit and spread it, according to a predefined procedure, on the outer lateral surface of the glue roller.

Generally, glue rollers of known type have a series of grooves extending axially on the outer lateral surface and configured to retain the glue which is fed from the feed circuit towards said outer lateral surface.

In detail, said grooves have a constant uniform depth and extend on the outer lateral surface throughout the axial length of the glue roller.

In further detail, the grooves are configured to retain the glue fed to them, while the rest of the outer lateral surface is scraped by the scraper element. In this way, it is possible to level and render uniform the layer of glue present on said lateral surface.

During the "roll-feed" labeling process, the glue is transferred from the above-mentioned grooves to at least the ends of each label, so as to provide the latter with the retention points necessary for gluing the same to the respective receptacle.

The excess glue removed from the outer lateral surface of the glue roller by means of the scraper element is recovered in a known manner and recirculated in the feed circuit, to be re-fed to the glue roller. This ensures uniform distribution of the glue in the grooves and allows performance of the labeling process with the desired degree of efficiency and cleanness.

Although the known glue application devices for labeling units represent a valid solution for applying glue to labels configured for application on receptacles, they can be further improved, in particular as regards to the efficiency of the labeling process and the working life of the components.

SUBJECT AND SUMMARY OF THE INVENTION

The object of the present invention is to provide a glue application device for a labeling unit which has high reliability and limited cost, and meets the needs specified above and connected with the glue application devices of known type .

According to the invention, this object is achieved by a glue application device as claimed in claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, two preferred non-limiting embodiments thereof are described below, purely by way of example and with the help of the accompanying drawings, in which:

- figure 1 is a schematic top view of a labeling unit comprising a glue application device according to a first embodiment of the present invention; - figure 2a is a larger-scale partially sectioned side view, with parts removed for the sake of clarity, of the glue application device of figure 1;

- figure 2b shows, on a larger scale, a detail of the glue application device of figure 2a;

- figure 2c is a larger-scale partial view with parts removed for the sake of clarity of a part of the glue application device of figure 2a; and

- figure 3 is a partially sectioned side view with parts removed for the sake of clarity of a glue application device according to a second embodiment of the present invention .

DETAILED DISCLOSURE

With reference to the attached figures, number 1 indicates as a whole a labeling unit configured to apply labels 2 obtained from a strip 3 of labeling material on receptacles 4, in particular bottles, cans or similar, configured to contain a pourable product, preferably a pourable food product .

The labels 2 applied by the unit 1 are glued labels, i.e. portions of labeling material of predefined length, cut from the strip 3 of labeling material initially wound on one or more storage reels (not illustrated) and spread with glue. Said labels 2 are subsequently transferred and applied to the outer surface of the respective receptacles 4.

The unit 1 comprises, essentially:

- a carousel 5 rotatable around a vertical axis Z, configured to convey a plurality of successive receptacles 4 along a horizontal feed path P, in the shape of an arc of a circle;

- an inlet station I through which the receptacles 4 to be labeled are fed to the carousel 5;

- an outlet station 0 receiving the labeled receptacle 4 from the carousel 5;

- an outlet conveyor, for example a star wheel (not illustrated) configured to receive from the carousel 5 the labeled receptacles 4 at the outlet station 0 and feed them towards a final conveyor (also not illustrated) ; and

- at least one labeling module 6 (illustrated schematically and only in the parts essentially necessary for understanding the present invention) arranged peripherally with respect to the carousel 5 and configured to feed a plurality of labels 2 to the carousel 5 and apply them to the respective receptacles 4, at an application station A.

In detail, the labeling module 6 comprises:

- at least one shaft (not illustrated) configured to rotatably support the above-mentioned storage reel from which the strip 3 of labeling material is unwound; a plurality of unwinding and feed rollers 7 (one only illustrated in figure 1) which support, in use, the strip 3 unwound from the storage reel and guide it along a feed path, preferably horizontal;

- a cutting device, for example a knife 8, configured to sequentially separate, in particular to cut, each label 2 from the strip 3 of labeling material, thus producing labels 2 having the same length;

- a transfer device, in particular a vacuum drum 10 for transferring the labels 2, rotatable about its own axis X, positioned peripherally to the carousel 5 and configured to receive, retain and feed each label 2 previously cut, and apply said label 2 to the respective receptacle 4, at the application station A.

Preferably, the drum 10 has a substantially cylindrical-toroidal lobed shape.

More precisely, the drum 10 receives sequentially, in use, the labels 2 previously cut by the knife 8, retains the labels 2 by suction on an own lateral surface and, after rotation by a given angle around the axis X, releases said labels 2 at the application station A, so that they are applied on the respective receptacles 4, according to a manner known and not described in detail.

The labeling module 6 further comprises a glue application device 11 configured to apply a certain predefined quantity of glue on each label 2, before the latter is applied to the relative receptacle 4.

In particular, the application device 11 is configured to spread each label 2 with a layer of glue at an inner side thereof.

It should be noted that by "inner side" of the label 2 we mean the back of the label 2, i.e. the side designed to cooperate in contact, that it to be rested on the lateral surface of the respective receptacle 4, after application. The inner side therefore constitutes the non-visible part of the label 2 after the application.

According to an alternative embodiment not illustrated, the application device 11 is configured to apply the glue directly on the strip 3 of labeling material, according to a method known and not described in detail .

As can be seen in detail in figure 2a, the application device 11 comprises:

- a glue roller 12 rotatable about an own longitudinal axis Y, preferably vertical and parallel to the axis X and to the axis Z, and configured to receive the glue on an outer lateral surface 13 thereof and transfer the glue to the respective labels 2; and

- a glue feed circuit 14 configured to feed in continuous mode the glue to the glue roller 12 during the labeling process, in particular to convey the glue from a storage tank 15 towards the lateral surface 13.

In detail, the circuit 14 comprises a distributor 14a arranged substantially tangent to the glue roller 12 and configured to spread with glue the lateral surface 13 of the glue roller 12.

In the example described, the circuit 14 further comprises :

- a glue feed duct 14b fluidically connected, on opposite sides, to the storage tank 15 and to the distributor 14a; and

- pumping means 19 fluidically interposed between the storage tank 15 and the duct 14b and adapted to pump molten glue through the duct 14b to the distributor 14a.

The application device 11 further comprises a glue distribution element, in particular a scraper element 16 which, in the example described, is defined by a curved blade, arranged peripherally to the glue roller 5 and at a certain radial distance from the lateral surface 13, in particular an infinitesimal radial distance with respect to the radial dimension of the glue roller 12.

In detail, the scraper element 16 is arranged operatively downstream of the distributor 14a, relative to the rotation direction of the glue roller 12, and is configured to remove the excess glue present on the lateral surface 13 after application by the distributor 14a, during rotation of the glue roller 12.

In further detail, the scraper element 16 is fixed to a support plate 17 carried by the labeling module 6 and, therefore, remains fixed during the labeling process, while the glue roller 12 rotates on itself. In this way, the scraper element 16 is also configured to level and render uniform the thickness of the layer of glue applied on the lateral surface 13 of the glue roller 12.

As can be seen in figure 2a, the lateral surface 13 of the glue roller 12 comprises a plurality of recesses 20 extending, i.e. receding, in a radial direction with respect to the lateral surface 13 and configured to house and retain the glue fed and distributed by the scraper element 16.

As is known, the recesses 20 allow the glue roller 12 to retain a greater quantity of glue compared to when the lateral surface 13 is smooth, i.e. without any recess.

According to this preferred non-limiting embodiment, the recesses 20 have a maximum depth D, with respect to the lateral surface 13, ranging from 0.015mm to 0.080mm, preferably equal to 0.050mm (figure 2c), and extend over the entire lateral surface 13.

According to an alternative embodiment not illustrated, the recesses 20 are distributed only in some areas of the lateral surface 13.

As can be seen in figure 2b, each recess 20 has a major axis M, a minor axis N intersecting the major axis M, in particular intersecting orthogonally the major axis M at a point defining a centre C of the relative recess 20, and two opposed sides 21 defining respective arcs of a circumference .

In detail, the two sides 21 intersect the minor axis N at own intermediate portions 21a and intersect with each other and with the major axis M at the own respective ends 21b (vertexes) .

In further detail, the sides 21 have radii of curvature of equal length and centres of curvature distinct from one another and arranged on opposite sides of the major axis M. In the specific example, the radii of curvature have a length ranging from 0.450mm to 1.050mm, preferably equal to 0.975mm.

In practice, the two sides 21 have the same curvature and, therefore, define substantially identical arcs of a circumference, arranged symmetrically with respect to the major axis M.

In light of the above, each recess 20 has a symmetrical shape with respect to the relative major axis M and with respect to the relative minor axis N.

Consequently, the intersection points of the sides 21 with the minor axis N are arranged at the same distance from the major axis M and the ends 21b are arranged on the major axis M at the same distance from the minor axis N.

More precisely, as can be seen in figure 2b, each recess 20 has an elongated shape along the major axis M, in particular a substantially "almond eye" shape.

In the example described, the major axis M has a length ranging from 0.600mm to 1.050mm, preferably equal to 0.900mm.

Furthermore, the minor axis N has a length ranging from 0.180mm to 0.550mm, preferably equal to 0.220mm.

According to the embodiment described and illustrated here, the recesses 20 are arranged on the lateral surface 13 so that the respective minor axes N are parallel to one another, and so that the respective major axes M are parallel to one another and transverse, in particular orthogonal, to the axis Y of the glue roller 12.

In practice, the recesses 20 are distributed "horizontally", i.e. with a horizontal orientation of the respective major axes M, on the lateral surface 13 of the glue roller 12.

Preferably, the recesses 20 are distributed on the lateral surface 13 with a density ranging from 0.5 recesses/mm² to 11 recesses/mm², in particular 2.77 recesses/mm². More precisely, the recesses 20 are distributed on the lateral surface 13 according to a pattern 22 of lines and columns .

In the specific case, the lines comprise recesses 20 aligned with one another in an orthogonal direction to the axis Y of the glue roller 12 and, therefore, having respective major axes M aligned with one another. Conversely, the columns comprise recesses 20 aligned with one another in a direction parallel to the axis Y and, therefore, having respective minor axes N aligned with one another .

In further detail, corresponding points taken respectively on a pair of successive recesses 20 along the same line and, therefore, along a direction parallel to and passing through the major axes M of said recesses 20, are positioned at a distance Q ranging from 0.450mm to 3.600mm, preferably equal to 1.800mm.

For example, considering the respective corresponding ends 21b of the sides 21 of a pair of successive recesses 20 belonging to the same line, they are positioned at the distance Q.

It should be noted that "corresponding ends 21b" refers to the ends 21b positioned on the same side of the respective minor axis N. Said distance Q therefore defines the circular pitch of the recesses 20.

In the same way, corresponding points taken respectively on a pair of successive recesses 20 along the same column and, therefore, in a direction parallel to and passing through the minor axes N of said recesses 20, are positioned at a distance R ranging from 0.100mm to 1.600mm, preferably equal to 0.400mm.

For example, the corresponding ends 21b of a pair of successive recesses 20 belonging to the same column are positioned at the distance R.

Said distance R therefore defines the axial pitch of the recesses 20.

According to this preferred non-limiting embodiment of the present invention, the above-mentioned pattern 22, according to which the recesses 20 are distributed on the lateral surface 13, comprises, for each pair of recesses 20 taken on a first line and/or column of the pattern 22, a recess 20 belonging to a second line and/or column immediately adjacent to the first one, the centre C of which is interposed between the two centres C of the recesses 20 of the pair, with respect to a direction parallel to the lines and/or to the columns.

More precisely, the above-mentioned centre C is interposed between, but not aligned with, the aforementioned centres C.

In other words, the recesses 20 belonging to a line and/or column are arranged "offset" with respect to the recesses belonging to the line and/or column immediately adjacent, so that the centres C of recesses 20 belonging to lines and/or columns immediately adjacent to one another identify segments W (only one of which is illustrated in figure 2b) transverse to the major axes M and minor axes N, i.e. segments W not aligned with directions parallel to the major axes M and minor axes N.

The operation of the unit 1 and, in particular, of the application device 11 according to the present invention will be described below, with particular reference to an initial condition in which a label 2 has just been cut by the knife 8 and is retained and fed by the drum 10 towards the application device 11.

In said condition, the distributor 14a continuously feeds the glue to the lateral surface 13 of the glue roller 12, while the scraper element 16 levels the glue on said lateral surface 13, so as to form a uniform layer of glue around the glue roller 12 and so as to fill the recesses 20.

When the label 2 arrives at the glue roller 12, the latter applies the above-mentioned layer of glue at least to portions of the inner side of the label 2, preferably at the ends of the inner side of the label 2.

More precisely, the glue abandons the lateral surface 13 and flows, at least partly, out of the recesses 20 to be transferred to the inner side of the label 2.

Subsequently, the label 2 is fed by the drum 10 towards the application station A, at which it is applied to the respective receptacle 4 fed by the carousel 5.

The process is repeated cyclically for each label 2 to be applied and for each receptacle 4 fed by the carousel 5.

With reference to figure 3, a glue application device in accordance with a second preferred embodiment of the present invention is indicated as a whole by 11' .

Since the application device 11' is similar in terms of structure and operation to the application device 11, the following description will be limited to outlining the differences between the two, using the same references for equivalent or similar features.

In particular, the application device 11' differs from the application device 11 by comprising a glue roller 12', the outer lateral surface 13' of which is provided with a plurality of recesses 20' similar to the recesses 20 of the glue roller 12 and different from the latter due to the fact that the major axes M of said recesses 20' are arranged parallel to the axis Y.

In practice, the recesses 20' are distributed "vertically" or with a vertical orientation of the respective major axes M, on the lateral surface 13' of the glue roller 12' .

Like the recesses 20, also the recesses 20' are distributed on the lateral surface 13' according to a pattern 22' of lines and columns, substantially corresponding to the pattern 22 rotated by 90°.

From an examination of the features of the application device 11, 11' according to the present invention, the advantages it offers are clear from the foregoing description .

In particular, the Applicant has ascertained, by detailed empirical analysis, that the configuration of the glue roller 12, 12' described and illustrated above and obtained by providing recesses 20, 20' shaped in accordance with the above-mentioned parameters, allows retention and release of the desired predefined quantity of glue, in an optimal efficient manner, reducing glue wastage and allowing uniform transfer of the same to the labels 2 to be applied to the receptacles 4.

Furthermore, the distribution of the recesses 20, 20' on the lateral surface 13, 13' according to the present invention allows an optimal ratio to be obtained between the area of the lateral surface 13, 13' occupied by the recesses 20, 20' and the remaining part of the lateral surface 13, 13' . In particular, this limits wear on the scraper element 16 while preserving the desired quantity of glue retained by the glue roller 12. In fact, the particular distribution of the recesses 20, 20' prevents the scraper element 16 from jamming and being stuck into the recesses 20, 20'. This also avoids repeated stress inside the application device 11, 11', which could otherwise cause undesired vibrations during the labeling process .

Clearly, modifications and variations may be made to the application device 11, 11' described and illustrated here without departing from the scope of protection defined by the claims .

Claims

1.- A glue application device (11, 11') configured to apply glue on labeling material (2, 3) configured for application on receptacles (4); said device (11, 11') comprising a glue roller (12, 12') rotatable about an own longitudinal axis (Y) and having an outer lateral surface (13, 13') configured to receive and transfer said glue;

said outer lateral surface (13, 13') comprising a plurality of recesses (20, 20'), each having:

- a major axis (M) ;

- a minor axis (N) intersecting said major axis (M) ; and

- two opposite sides (21) defining respective arcs of a circumference, intersecting said minor axis (N) at respective intermediate portions (21a) thereof and intersecting each other and said major axis (M) at the respective ends (21b) thereof.

2.- The device as claimed in claim 1, wherein said sides (21) have radii of curvature of equal length and centres of curvature distinct from one another and arranged on opposite sides relative to said major axis (M) .

3.- The device as claimed in claim 2, wherein said radii of curvature have a length ranging from 0.450mm to

1.050mm, preferably equal to 0.975mm.

4.- The device as claimed in claim 2 or 3, wherein each recess (20, 20') has a symmetrical shape with respect to the relative major axis (M) and with respect to the relative minor axis (N) .

5.- The device as claimed in any one of the preceding claims, wherein each recess (20, 20') has a depth (D) , with respect to said outer lateral surface (13, 13' ) , ranging from 0.015mm to 0.080mm, preferably equal to 0.050mm.

6.- The device as claimed in any one of the preceding claims, wherein said major axis (M) has a length ranging from 0.600mm to 1.050mm, preferably equal to 0.900mm.

7.- The device as claimed in any one of the preceding claims, wherein said minor axis (N) has a length ranging from 0.180mm to 0.550mm, preferably equal to 0.220mm.

8.- The device as claimed in any one of the preceding claims, wherein corresponding points (21b) taken respectively on a pair of successive recesses (20, 20') along a direction passing through said major axis (M) are positioned at a distance (Q) ranging from 0.450mm to 3.600mm, preferably equal to 1.800mm.

9.- The device as claimed in any one of the preceding claims, wherein corresponding points (21b) taken respectively on a pair of successive recesses (20, 20') along a direction passing through said minor axis (N) are positioned at a distance (R) ranging from 0.100mm to 1.600mm, preferably equal to 0.400mm.

10.- The device as claimed in any one of the preceding claims, wherein said recesses (20, 20') are distributed on said outer lateral surface (13, 13' ) according to a pattern (22, 22') of lines and columns;

wherein the major axis (M) and the minor axis (N) of each recess (20, 20') intersect one another orthogonally at a respective intersection point defining a centre (C) of the respective recess (20, 20');

and wherein for each pair of recesses (20, 20') taken on one of said lines and/or columns, said pattern (22, 22') comprises a recess (20, 20') belonging to another of said lines and/or columns immediately adjacent to said one of said lines and/or columns the centre (C) of which is interposed between the centres (C) of the recesses (20, 20') of said pair, with respect to a direction parallel to said lines and/or columns.

11.- The device (11) as claimed in any one of the preceding claims, wherein the major axis (M) of each recess (20) is arranged transversally with respect to said longitudinal axis (Y) of said glue roller (12), preferably orthogonally with respect to said longitudinal axis (Y) .

12.- The device (11') as claimed in any one of the preceding claims, wherein the major axis (M) of each recess (20') is arranged parallel with respect to said longitudinal axis (Y) of said glue roller (12') .

13.- A labeling unit (1) configured to apply labels (2) on receptacles (4) configured to contain a pourable product; said unit (1) comprising:

- a conveyor (5) configured to feed a plurality of said receptacles (4) along a feed path (P) ;

- a transfer device (10) configured to receive a succession of said labels (2), one after the other, and to feed said labels (2) towards an application station (A), at which said labels (2) are applied to respective receptacles (4) ; and

- a glue application device (11, 11') as claimed in any one of the preceding claims and configured to apply at least one layer of glue on at least a portion of said labels (2) before they are applied on the respective receptacles ( 4 ) .