WO2017032579A1

WO2017032579A1 - A label transfer device for a labeling apparatus

Info

Publication number: WO2017032579A1
Application number: PCT/EP2016/068837
Authority: WO
Inventors: James Carmichael
Original assignee: Sidel Participations
Priority date: 2015-08-25
Filing date: 2016-08-08
Publication date: 2017-03-02
Also published as: EP3135594A1

Abstract

There is described a label transfer device (7, 7') for conveying a label (2) along a path (Q). The label transfer device (7, 7') comprises a transfer drum (20) rotatable around a rotation axis (D) to define the path (Q) and delimited by an outer lateral surface (21) having a plurality of suction holes (30a, 30b, 30c) to retain the label (2) on the outer lateral surface (21) itself during transfer along the path (Q); a suction source (23) apt to exert a suction force on the label (2) through at least a fraction of the plurality of suction holes (30a, 30b, 30c); and a stationary distributor plate (24) rotatably supporting the transfer drum (20) and having at least one air port (25) configured to fluidically connect the suction source (23) to the plurality of suction holes (30a, 30b, 30c). The suction source (23) comprises at least one suction generation unit (35, 35' ) fluidically connected to the air port (25) and integrally mounted to the distributor plate (24) or being at least partially an integral part of the distributor plate (24') itself.

Description

A LABEL TRANSFER DEVICE FOR A LABELING APPARATUS

TECHNICAL FIELD

The present invention relates to a label transfer device for a labeling apparatus. In particular, the present invention relates to a label transfer device comprising a transfer drum having an outer lateral surface for conveying labels retained on the outer lateral surface itself from a receiving position to an application position.

BACKGROUND ART

Labeling apparatuses for automatically attaching labels onto articles of all sort, such as receptacles, containers, vessels, bottles etc., are well known in the art and their use is widespread in the packaging industry.

One typical label type, used with a particular kind of articles, namely, beverage bottles or vessels, is the label commonly known as "sleeve label", which is formed in a tubular configuration and then applied onto the respective article. More specifically, the sleeve labels are wrapped around respective cylindrical article mandrel members conveying on top the articles to be labeled and then welded at their overlapping ends. At the end of the welding operation, the mandrel members are retracted so that the articles engage the corresponding tubular labels. A heat shrinking operation is then carried out to make the labels adhere onto the respective articles.

A possible typical alternative is the so called "self-stick label", which is directly wrapped around at least part of the respective article and glued thereto. In general, in the known labeling apparatuses, prior to the application on the respective articles, the labels are commonly transported by means of a label transfer device comprising a transfer drum.

As known, in a labeling apparatus of the "self- stick label" type, which the following description will refer to without any limitative scope, each label of a succession of labels is attached on the outer surface of one respective article. Prior to the application of the label onto the respective article glue is supplied onto the back surface of the label itself.

In these machines, the articles are typically carried by a conveying carrousel along an article path so as to advance towards an application position at which one respective label is stuck onto each article. At the same time, in the known labeling apparatuses, a web of labeling material is fed from a roll-feeding unit towards a label transfer device comprising a transfer drum .

In particular, the web of labeling material is advanced towards an outer lateral surface of the transfer drum. During feeding, the web of labeling material is brought into contact with cutting means of a cutting unit so as to cut the web of labeling material into labels of defined and appropriate lengths. Then each label is retained on the outer lateral surface of the transfer drum and is conveyed, by rotation of the transfer drum around its axis towards the application position. Furthermore, prior to reaching the application position, each label interacts with a gluing unit which applies glue, e.g. by means of a rotating glue roller tangentially cooperating with the transfer drum or by means of spray or injection systems working in a contact or non-contact manner, onto the back surface of the label. After that, the label can be stuck onto one respective article.

In particular, during transfer towards the application position, the labels are retained by respective retaining sections of the outer lateral surface of the transfer drum; these retaining sections are equally spaced angularly around the axis of the transfer drum and are separated from each other by respective transition sections, along which labels fed from the roll-feeding unit slide prior to reaching the respective retaining sections.

For proper performance of these operations, accurate handling of the labels is pursued through retention thereof on the outer lateral surface of the transfer drum, i.e. by applying suction on the labels in a controlled manner. To this purpose, the outer lateral surface of the transfer drum comprise a plurality of suction holes that can be fluidically connected with a suction source.

Generally, the suction source comprises one single vacuum pumping unit having a plurality of pressure reducers and respective connecting means for connecting the pumping unit and the pressure reducers to the transfer drum for establishing the fluidic connection with the plurality of suction holes.

For this purpose, typically, the label transfer device further comprises a stationary distributor plate and a wear plate rotatable around the axis of the transfer drum.

The distributor plate is provided with a plurality of air ports, each of which is connected to a respective pressure reducer by respective connecting means, such as pipes and tubes. The air ports again are generally fluidically connected to one or more suction channels of the wear plate, which are fluidically connected to the suction holes of the transfer drum.

One drawback of the described label transfer device lies in its large size and mass needed to be housed within the labeling apparatus.

Additionally, the use of a vacuum pumping unit, the use of a plurality of pressure reducers and the use of the connecting means comes along with high economical costs and increased maintenance issues.

DISCLOSURE OF INVENTION

It is therefore an object of the present invention to provide a label transfer device for a labeling apparatus, which is designed to overcome, in a straightforward and low-cost manner, the aforementioned drawbacks .

According to the present invention, there is provided a label transfer device as claimed in claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

Three non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, in which:

Figure 1 shows a top plan schematic view of a labeling apparatus with a label transfer device according to the present invention for applying labels onto articles advancing along an article path; Figure 2 shows a larger-scale side view of the label transfer device of Figure 1 with parts removed for clarity;

Figure 3 shows a larger-scale sectioned side view of a detail of the label transfer device of Figure 2 with parts removed for clarity;

Figure 4 shows a scheme of controlling the label transfer device of Figures 1 and 2; ad

Figure 5 is analogous to Figure 3 and shows another embodiment of the label transfer device according to the present invention with parts removed for clarity;

Figure 6 shows a sectioned side view of a detail of a further embodiment of a label transfer device according to the present invention;

Figure 7 shows a section view of a detail of the further embodiment of Figure 6 along plane VII - VII of Figure 6;

Figure 8 shows a further section view of the same detail as shown in Figure 7 along the plane VIII - VIII of Figure 6; and

Figure 9 shows a scheme of controlling the label transfer device of Figure 6 similar to the scheme of Figure 4.

BEST MODES FOR CARRYING OUT THE INVENTION

Number 1 in Figure 1 indicates as a whole a labeling apparatus, only partially shown to the extent that is necessary for the comprehension of the present invention .

Apparatus 1 is adapted to be used for handling, transferring and applying labels 2 to respective articles 3 or, more specifically, receptacles, such as bottles, as said articles 3 are advanced along an article path P.

In more detail, apparatus 1 comprises a carrousel 4 configured to support a plurality of articles 3 on its periphery and to rotate the same along path P around an axis A of the carrousel itself.

Axis A preferably extends vertically and the path P is arc-shaped and extends horizontally.

Articles 3 can be rotated as they are advanced along the path P by carrousel 4 and as labels 2 are applied to the articles 3 themselves.

Apparatus 1 further comprises:

a label transfer device 7 according to the present invention, which is configured to transfer a succession of labels 2 from a receiving position 8 to an application position 9 along a label path Q tangential to path P at the application position 9 itself;

a feeding unit 10 for feeding a web 11 of labeling material to the receiving position 8;

- a cutting unit 12 of known type, arranged adjacent to receiving position 8 for cutting off the succession of labels 2 from the web 11 of labeling material; and

- a glue application unit 13 arranged adjacent to at least a portion of label transfer device 7 and between receiving and application position 8, 9 with reference to path Q and configured to apply, at a gluing position 14, a given amount of glue on the back side of each label 2 advancing along the path Q prior to reaching the application position 9.

More specifically, cutting unit 12 comprises: - a rotary cutting drum 17, having an axis B parallel to axis A, arranged adjacent to at least a portion of label transfer device 7 and carrying, on its outer lateral surface, the web 11; and

- a stationary cutter blade or cutter 18 carried in a fixed position on one side of rotary cutting drum 17 and proximal to receiving position 8 so as to cooperate, in use, with the rotary cutting drum 17 to cut one label 2 at a time from the web 11 of labeling material. In particular, cutting unit 12 is adapted to cut labels 2 of given lengths and substantially rectangular shape, each having a leading end portion 2a and a trailing end portion 2b.

With reference to Figure 1, glue application unit 13 preferably comprises a glue application roller 19 having an axis C parallel to axes A, B.

In particular, glue roller 19 is mounted to rotate about its axis C and has an outer cylindrical lateral surface, which is covered by melted glue continuously fed by a glue feeding system, known per se and not shown. Glue roller 19 is adapted to spread a pattern of glue onto the backside of each label 2 advancing along path Q. In particular, the pattern is provided on the side of the label 2 destined to be stuck to the surface of a respective article 3.

As a possible alternative not shown, glue application unit 13 may comprise a spray or an injector system in place of the glue roller 19. The glue pattern may comprise a layer of glue and/or one or more glue strips and/or one or more glue spots.

With particular reference to Figures 2 and 3, label transfer device 7 comprises:

- a transfer drum 20 rotatable around a rotation axis D, parallel to axes A, B, C to define the path Q and delimited by an outer lateral surface 21 to retain labels 2 during transfer along path Q;

- a suction source 23 apt to exert a suction force on labels 2 for retaining them on outer lateral surface 21; and

- a stationary distributor plate 24 having one or more air ports 25, in the example shown three, configured to fluidically connect the suction source 23 selectively to outer lateral surface 21.

In particular, distributor plate 24 has a substantially annular configuration; and is intersected by a transfer drum shaft 20a rotatable around axis D of transfer device 7. In more detail, transfer drum 20 is mounted to transfer drum shaft 20a and is arranged peripherally adjacent, preferably tangential, to rotary cutting drum 17 at receiving position 8, to glue application roller 19 at gluing position 14 and to carousel 4 at application position 9.

As visible in Figure 1, application position 9 is positioned at a given angular distance from receiving position 8 about the axis D of rotation of transfer drum 20.

In more detail, with particular reference to Figures 1 and 2, outer lateral surface 21 of transfer drum 20 comprises a plurality of interaction elements 27, in particular pads. As shown in Figure 1, interaction elements 27 are slightly protruding from outer lateral surface 21 and are designed to engage, in use, with the leading 2a and the trailing end portion 2b of one respective label 2.

Transfer drum 20 further presents a plurality of retaining sections 28, in the particular example three, each delimited by a pair of interaction elements 27 and adapted to retain the labels 2 during transport along path Q, in particular from receiving position 8 to application position 9.

Furthermore, retaining sections 28 of outer lateral surface 21 are equally spaced angularly around axis D of transfer drum 20 and are separated from each other by respective transition sections 29. In particular, each transition section 29 extends between two respective retaining sections 28. Each transition section 29 is adapted to permit one label 2 being fed from feeding unit 10 to slide prior to reaching the respective retaining section 28.

In addition, outer lateral surface 21 and in particular retaining sections 28, transition sections 29 and interaction elements 27 comprise a plurality of suction holes 30a, 30b, 30c selectively communicating with suction source 23.

More specifically, suction holes 30a, 30b, 30c are configured to be fluidically connected in a selective manner to suction source 23 through air ports 25 of distributor plate 24.

Furthermore, transfer drum 20 has a plurality of internal passages 31 adapted to be fluidically connected to suction holes 30a, 30b, 30c and air ports 25. Hence, suction holes 30a, 30b, 30c are configured to be fluidically connected in a selective manner to suction source 23 through air ports 25 and internal passages 31.

In addition, interaction elements 27 are configured to establish contact of leading end portion 2a and trailing end portion 2b of each label 2 retained on outer lateral surface 21 with glue application roller 19 during rotation of labels 2 along path Q at gluing position 14.

Consequently, in use, glue is transferred from glue application roller 19 onto the back surface of the leading and trailing end portions 2a, 2b of labels 2. In particular, glue is applied on leading and trailing end portions 2a, 2b prior to reaching application position 9 at which, in use, first the back surface of leading end portion 2a of each label 2 gets into contact with one respective article 3; upon further advancement of the label 2 along path Q and rotation and further transport of the respective article 3 along path P, the label 2 is transferred to such article 3 and, finally, the back surface of the trailing end portion 2b is attached to the article 3 itself.

With particular reference to Figure 3, distributor plate 24 has a port plate 24a presenting air ports 25 and a structure plate 24b configured to carry port plate 24a. In this specific example distributor plate 24 has a two plate structure, but it must be understood that distributor plate 24 can be constructed as a single plate combining the features of port plate 24a and structure plate 24b.

As illustrated in Figures 1 to 3, label transfer device 7 further comprises a rotation plate 32, in particular a wear plate, mounted, in particular screwed to transfer drum 20 and placed adjacent to distributor plate 24. In particular, rotation plate 32 has a substantially annular configuration and is intersected by transfer drum shaft 20a. Accordingly, rotation plate 32 is rotatable around rotation axis D of transfer drum 20. In particular, distributor plate 24 and rotation plate 32 are placed so as to slightly contact each other .

Additionally, rotation plate 32 comprises one or more air channels 33, in the specific example three, fluidically connected to air ports 25. Furthermore, air channels 33 are in fluidic connection with internal passages 31 of transfer drum 20.

Thus, overall, suction holes 30a, 30b, 30c are configured to be fluidically connected in a selective manner to suction source 23 through air ports 25, internal passages 31 and air channels 33.

With reference to Figures 1, 2 and 3, label transfer device 7 also comprises a support structure 34 for carrying on top distributor plate 24 and for supporting transfer drum shaft 20a. Support structure 34 itself is supported in a known manner by portions of labeling apparatus 1 known as such and not illustrated.

In more detail, support structure 34 comprises at least two longitudinal bars 34a disposed adjacent and parallel to each other and parallel to distributor plate 24. Furthermore, support structure 34 presents a carrier portion 34b mounted to longitudinal bars 34a and configured to carry distributor plate 24. Additionally, support structure 34 has a plurality of balancing means 34c, such as spring elements, adapted to allow for keeping slight contact between distributor plate 24 and rotation plate 32 under all working conditions and under rotational oscillations possibly occurring in use.

More specifically, balancing means 34c are supported by carrier portion 34b and are interposed between carrier portion 34b and distributor plate 24. In particular, distributor plate 24 is arranged so that support plate 24b is interposed between balancing means 34c and port plate 24a. More specifically, balancing means 34c are in contact with support plate 24b.

With reference to Figures 1 to 3, suction source 23 comprises one or more suction generation units 35, in the specific example six. It must be noted that advantageously suction source 23 comprises more than one suction generation unit 35 for taking into account varying phases of the transport of labels 2 from receiving position 8 to application position 9, as known in the state-of-the-art.

In particular, a transferring phase when one respective label 2 is transferred from the cutting unit 12 to outer lateral surface 21, a pre-glue phase after delivery of one respective label 2 to one respective retaining section 28 and prior to applying glue onto the respective label 2, a post-glue phase after application of glue onto the respective label 2 and an intermediate phase after application of the respective label 2 on one respective article 3. In the intermediate phase, it may be necessary to provide for a suction on the respective label 2 in the case that an article 3 is not present and the respective label 2 cannot be applied. Accordingly, in this case, the label 2 must be further retained on outer lateral surface 21 and further conveyed.

In particular, each one of the phases requires the application of different suction forces on the labels 2 and eventually it is sufficient to apply suction only to a fraction of suction holes 30a, 30b, 30c.

Furthermore, each suction generation unit 35 is configured to be fluidically connected to air ports 25. Additionally, each suction generation unit 35 is integrally mounted to distributor plate 24. In particular, "integrally mounted" means that each suction generation unit 35 is in direct contact with distributor plate 24 and is fluidically connected to air ports 25 without any further connecting means, such as tubing, pipes, hoses, etc.

As suction generation units 35 are identical to each other, only one will be described in detail hereafter for the sake of clarity and conciseness.

Suction generation unit 35 comprises:

- a main portion 36 mounted to distributor plate 24 and adapted to generate suction on suction holes 30a,

30b, 30c; and

- a discharge portion 37 supported by main portion 36 and configured to discharge air from the suction generation unit 35 itself.

Discharge portion 37 is additionally adapted to reduce the noise level of suction generation unit 35. In particular, discharge portion 37 is provided with a discharge channel 37a for discharging air from suction generation unit 35 surrounded by silencing means 37b.

Furthermore, label transfer device 7 comprises a fluidic line configured to connect suction holes 30a, 30b, 30c to discharge portion 37.

Suction generation unit 35, in particular main portion 36, comprises a constricted and narrowed section portion 38 being part of said fluidic line. Additionally, air ports 25 are parts of the above- mentioned fluidic line.

Overall, suction generation unit 35 is configured to operate according to the Venturi effect. The Venturi effect relates to a decrease in pressure of a flow of gas or fluid through a constricted portion of a tube, a pipe or similar and the simultaneous increase in flow speed .

Therefore, suction generation unit 35 comprises at least one compressed air inlet 42 to feed compressed air into the constricted section portion 38. Furthermore, suction generation source 35 further comprises a pressure chamber 43 interposed between constricted section portion 38 and compressed air inlet 42 and a compressed air conduit 44 for feeding the compressed air into constricted section portion 38. In particular, pressure chamber 43 has an annular configuration and surrounds constricted section portion 38. Additionally, air conduit 44 has an annular configuration, in particular a truncated cone configuration.

Furthermore, air conduit 44 is configured to guide compressed air into constricted section portion 38 so as to form a compressed air flow incident to a central axis X of constricted section portion 38 of the fluidic line perpendicular to distributor plate 24. As an alternative not shown, air conduit 44 can be configured to guide the compressed air flow parallel to axis X. In the example of Figure 3, in particular, the compressed air flow occurs along a plurality of directions Y parallel to inner walls 44a of a main portion 44b of air conduit 44. It must be understood, that in the specific case of Figure 3 air conduit 44 describes a continuous annular configuration so that air flows along an infinite number of parallel directions Y. However, the same technical effect can be achieved by having a discrete number of air channels (not shown) .

Accordingly to what is mentioned above, directions

Y are inclined with respect to central axis X.

Furthermore, each direction Y or equivalently the compressed air flow forms an obtuse angle a with respect to central axis X towards discharge portion 37. In particular, it has been found to arrange air conduit 44 in such a way that obtuse angle a lies between 120° to 150°, preferably between 130° to 140° and most preferably at about 135°.

With particular reference to Figure 3, suction generation unit 35, in particular main portion 36 comprises :

- a suction portion 46 placed adjacent to air ports 25 of distributor plate 24 and adapted to generate the suction on the air ports 25 themselves; and

- a diffuser portion 47 adjacent to discharge portion 37 and configured to guide and diffuse air towards discharge portion 37.

Furthermore, constricted section portion 38 is interposed between suction portion 46 and diffuser portion 47.

In more detail, both suction portion 46 and diffuser portion 47 have tapered configurations towards constricted section portion 38.

Thus, in use, compressed air is fed through compressed air inlet 42 into pressure chamber 43; from here the compressed air flows through air conduit 44 into constricted section portion 38 and then, through diffuser portion 47, towards discharge portion 37. By means of the Venturi effect a flow of air is consequently induced along the fluidic line from suction holes 30a, 30b, 30c to discharge portion 37 passing through suction portion 46, constricted section portion 38 and diffuser portion 47. Thereby, suction is applied on labels 2 retained on outer lateral surface 21.

In further detail, main portion 36 is at least partially housed within support plate 24b and port plate 24a of distributor plate 24. Main portion 36 has a fixing portion 48 carrying suction portion 46 and a first fraction 38a of constricted section portion 38 removably fixed to distributor plate 24. In particular, fixing portion 48 is partially housed within a recess 24c of support plate 24b and directly contacts port plate 24a at a first end 48a. In particular, fixing portion 48 is screwed into support plate 24b.

Main portion 36 further comprises an end portion 49 carrying diffuser portion 47 and a second fraction 38b of constricted section portion 38. End portion 49 is removably mounted to a second end 48b of fixing portion 48. In particular, end portion 49 is screwed onto fixing portion 48.

Hence, in cooperation, fixing portion 48 and end portion 49 delimit constricted section portion 38, pressure chamber 43 and air conduit 44. In particular, the size and form of pressure chamber 43 and air conduit 44 are defined by the outer shapes of both fixing portion 48 and end portion 49. Thus, the sizes of air conduit 44 and pressure chamber 43 can be varied exchanging either one of fixing portion 48 or end portion 49, preferentially for ease of operation end portion 49 or both.

As visible in Figures 3 and 4, suction generation unit 35 further comprises sensor means 50 adapted to determine the actual suction force applied by suction generation unit 35 itself. Sensor means 50 comprise a sensor element 51, such as a pressure sensor or transducer, for determining the pressure in the proximity of air port 25 and an air passage 52 adapted to fluidically connect air ports 25 to sensor element 51. In particular, sensor element 51 is mounted to distributor plate 24, more specifically to support plate 24b. Air passageway 51 is provided within distributor plate 24.

With reference to Figure 4, label transfer device 7 comprises a control unit 55 for controlling the suction force applied by each suction generation unit 35 of suction source 23.

For this reason, control unit 55 is configured to receive a signal or signals from sensor means 50 and to compare the signal received with preset values.

Furthermore, suction source 23 comprises a compressed air pressure assembly 56 adapted to feed compressed air to each suction generation unit 35, in particular to each compressed air inlet 42. More specifically, each compressed air inlet 42 is fluidically connected to compressed air pressure assembly 56 by connecting means 57.

Control unit 55 is configured to control compressed air pressure assembly 56 as a function of the signals received from sensor means 50.

Compressed air pressure assembly 56 comprises:

- a compressed air supply source 58 for providing compressed air, preferentially being part of a centralized factory compressed air supply or a compressor; and

- a pressure adjusting unit 59 having one or more pressure adjusting elements 60, in the example shown six (only three of which are visible in Figure 4), for adjusting the pressure of the compressed air fed to the respective suction generation units 35. In particular, each pressure adjusting element 60 is fluidically connected to the respective compressed air inlet 42 by connecting means 57.

With reference to Figure 5, number 7' shows in detail an alternative embodiment of a label transfer device being part of label apparatus 1 according to the present invention; as label transfer device 7' is similar to label transfer device 7, the following description is limited to the differences between them, and using the same references, where possible, for identical or corresponding parts.

In particular, label transfer device 7' differs from label transfer device 7 in the configuration of suction generation units 35' forming suction source 23.

In particular, suction generation units 35' are at least partially integral parts of a distributor plate 24' of label transfer device 7' .

As suction generation units 35' are identical to each other, only one will be described in detail hereafter for the sake of clarity and conciseness.

In more detail, suction generation unit 35' has a main portion 36' comprising a suction portion 46', a narrowed and constricted section portion 38' and a diffuser portion 47' . In the embodiment of Figure 5, suction portion 46' and a first fraction 38' a of constricted section portion 38' are carried by distributor plate 24'. More specifically, suction portion 46' and first fraction 38' a are provided in distributor plate 24'.

Distributor plate 24' comprises a port plate 24' a and a support plate 24'b and suction portion 46' and first fraction 38' a are specifically incorporated into said support plate 24'b.

Furthermore, diffuser portion 47' and a second fraction 38'b of constricted section 38' are carried by an end portion 49' of main portion 36' .

End portion 49' is configured to be removably mounted to distributor plate 24', in particular to support plate 24b' .

Support plate 24'b presents a seat opening 24' c for housing end portion 49' within distributor plate 24'. In particular, seat opening 24' c is arranged so that suction portion 46' and first fraction 38' a are interposed between port plate 24' a and seat opening 24' c.

Main portion 36' of suction generation unit 35' is assembled by placing end portion 49' into seat opening 24' c. Furthermore, the outer shape of end portion 49' and the inner shape of seat opening 24' c define in cooperation a pressure chamber 43' for receiving compressed air from compressed air inlet 42 and an air conduit 44' for guiding the compressed air into constricted section portion 38' in a manner as described with respect to the embodiment of Figure 3.

Furthermore, suction generation unit 35' comprises adjustment means 61' for adjusting the size of air conduit 44'. Adjustment means 61' are further adapted to adjust the size of pressure chamber 43' . In particular, adjustment means 61' are configured to move end portion 49' to or away from air ports 25, in particular to or away from suction portion 46' .

Adjustment means 61' are adapted to transform a rotation of end portion 49' into a linear movement.

In detail, adjustment means 61' are defined by a first thread portion 62' of seat opening 24' c and a second thread portion 63' of end portion 49' configured to interact with thread portion 62'. Additionally, end portion 49' is provided with a nut-screw section 64' for facilitating rotation of end portion 49' for linearly moving end portion 49' within seat opening 24' c.

Suction generation units 35' work according to the same functional principle of suction generation units 35. In particular, each suction generation unit 35' operates according to the Venturi effect. The compressed air entering constricted section portion 38' flows to diffuser portion 47' and further to discharge portion 37. Due to the Venturi effect a further air flow is induced along the fluidic line from suction holes 30a, 30b, 30c to discharge portion 37.

Thus, overall, in use, a suction force is applied on labels 2 retained on outer lateral surface 21 by suction source 23. In particular, suction force is generated through suction holes 30a, 30b, 30c by the suction generation units 35, 35' , which operate according to the Venturi effect.

In this way, labels 2 received at receiving position 8 from cutting unit 12 are safely retained on respective retaining section 28 and are conveyed in a manner described in more detail above from receiving position 8 to application position 9, where they are applied on respective articles 3.

With reference to Figures 6 to 9, number 7'' shows in detail an alternative embodiment of a label transfer device being part of label apparatus 1 according to the present invention; as label transfer device 7'' is similar to label transfer device 7', the following description is limited to the differences between them, and using the same references, where possible, for identical or corresponding parts.

In particular, label transfer device 7'' differs from label transfer device 7' in the configuration of suction generation units 35'' forming suction source 23.

In more detail, each suction generation unit 35' ' comprises a functional group 68'' adapted to generate a suction force and being at least partially an integral part of distributor plate 24'.

In more detail, functional group 68 '' comprises :

an air outlet portion 69' ' configured to be fluidically connected in a selective manner to suction holes 30a, 30b, 30c and air ports 25; and

- an air flow generation device 70'' adapted to generate a flow of air from suction holes 30a, 30b, 30c to air outlet portion 69' ' through air ports 25 and, in particular, out of air outlet portion 69' ' .

Furthermore, suction holes 30a, 30b, 30c are configured to be fluidically connected in a selective manner to air outlet portions 69' ' through air ports 25 and internal passages 31.

In more detail, each air flow generation device 70'' is adapted to generate the flow of air so as to provide for the suction force for retaining labels 2 on surface 21.

Preferably, each air flow generation device 70'' comprises :

a rotating body 71'', in particular a fan, adapted to rotate around a respective rotation axis E' ' parallel to axis D and to generate through rotation around rotation axis E' ' the flow of air from suction holes 30a, 30b, 30c to air outlet portion 69' ' through air ports 25; and

an actuation device 72'' adapted to actuate rotation of rotating body 71''.

With particular reference to Figures 6 to 8, each air flow generation device 70'' is realized as a side channel pump.

Therefore, preferably, each air flow generation device 70'' also comprises a connecting channel 73'' fluidically connecting air ports 25 with air outlet portion 69' ' . In particular, each connecting channel 73' ' is interposed between air ports 25 and air outlet portion 69' ' and has an inlet portion 73a' ' through which air enters channel 73' ' and an outlet portion 73b' ' through which air exits from channel 73' ' . Preferably, each connecting channel 73' ' has an arc- shaped configuration.

Furthermore, each rotating body 71'' is adapted to generate the flow of air from the respective suction holes 30a, 30b, 30c to the respective air outlet portion 69' ' through the respective air ports 25 by generating a flow of air within the respective connecting channel 73' ' , in particular from inlet portion 73a' ' to outlet portion 73b' ' .

In more detail, with particular reference to Figures 7 and 8, each air flow generation device 70'' further comprises a housing 74'' carrying the respective connecting channel 73' ' and having a hollow space 74a' ' , in particular of cylindrical shape, housing therein the respective rotating body 71'' .

More specifically, each space 74a' ' and the respective connecting channel 73' ' fluidically communicate with one another. In particular, each space 74a' ' is spaced apart from the respective connecting channel 73' ' . Even more particularly, each connecting channel 73' ' is arranged above the respective space 74a'' . Thus, preferably, also rotating body 71'' is arranged spaced apart, in particular below, from the respective connecting channel 73' ' .

In even further detail each rotating body 71'' comprises a plurality of blades 71a' ' , adapted to move within the respective space 74a' ' , in particular through rotation of the rotating body 71'' itself. The respective blades 71a'' of each rotating body 71'' are configured to generate the flow of air within the respective connecting channel 73' ' , in particular from the respective inlet portion 73a' ' to the respective outlet portion 74'', as a result of the drag forces acting between the air directly moved by the respective blades 71a' ' and the air present in the respective connecting channel 73' ' .

With particular reference to Figures 6 to 9, preferably, each actuation device 72'' comprises an electrical motor 75' ' , in particular a brushless motor, having a rotating shaft 75a' ' connected to rotating body 71''. In particular, the respective rotating shaft 75a'' of each motor 75' ' extends along the respective axis E' ' and is configured to rotate around the respective axis E' ' for actuating rotation of the respective rotating body 71" .

Favorably, each functional group 68'' also comprises a casing 76'' having an inner space 77'' being arranged between air outlet portion 69' ' and air ports 25, in particular inner space 77'' being in fluid connection with the respective air outlet portion 69' ' and the respective air ports 25. In further detail, at least a portion of functional group 68'', in particular casing 76'' is an integral part of support plate 24b' .

However, it must be noted, that in an alternative embodiment not shown, each functional group 68'', in particular the respective casing 76'' could be integrally mounted to distributor plate 24 in a manner similar to the embodiment shown in Figures 1 to 4; i.e. each functional group 68'' would be supported by plate 24b. In particular, in the case of the alternative embodiment not shown, "integrally mounted" means that the respective functional group 68'' of each suction generation unit 35' ' is in direct contact with distributor plate 24 and is fluidically connected to air ports 25 without any further connecting means, such as tubing, pipes, hoses, etc.

Preferably, each rotating body 71'' is arranged within the respective inner space 77'' and each actuation device 72'', in particular motor 75'' is mounted to an external portion 78'' of casing 76''. More specifically, each housing 74'' is arranged within the respective inner space 77'' and therewith also each rotating body 71'' and the respective connecting channel 73' ' are arranged within the respective inner space 77''. In particular, each housing 74'' is an integral part of support plate 24b' .

Furthermore, casing 76'' carries the respective air outlet portion 69' ' . In particular, each air outlet portion 69'' comprises at least one outlet hole 79'' arranged along the periphery of casing 76''.

In further detail, each inner space 77'' comprises an intake zone 81'' configured to be in direct fluidic connection with respective air ports 25 and an outlet zone 82'' being in direct fluidic connection with the respective air outlet portion 69' ' , in particular the respective outlet hole 79''.

Furthermore, each connecting channel 73' ' is arranged between the respective intake zone 81'' and the respective outlet zone 82'' and fluidically connects the respective intake zone 81'' with the respective outlet zone 82 ' ' .

With particular reference to Figure 9, preferably, transfer device 7'' further comprises a control unit 55' ' adapted to selectively control the suction force applied by suction generation units 35' ' .

Control unit 55' ' is configured to receive a signal or signals from sensor means 50 about the suction forces applied by each one of suction generation units 35' ' and is further configured to compare the signal or the signals about the suction forces received with the needed/desired suction force values.

In particular, control unit 55' ' is configured to receive a signal or signals from sensor elements 51 about the suction force applied and to compare the suction force with the needed/desired suction force to be applied. Furthermore, control unit 55' ' is configured to selectively control each one of suction generation units 35' ' in dependence of the suction force determined for the specific suction generation unit 35' ' .

More precisely, control unit 55' ' is designed to cooperate with a power supply unit 83' ' of transfer device 7'' for controlling each one of suction generation units 35' ' in dependence of the suction force determined. More specifically, control unit 55' ' controls power supply unit 83' ' for selectively controlling each one of actuation devices 72''.

In particular, transfer device 7'' comprises electrical wiring 84'' for connecting power supply unit 83' ' with suction generation units 35' ' , in particular with the respective actuation devices 72''. In further detail, control unit 55' ' controls the suction force applied by each one of suction generation units 35' ' by cooperating with power supply unit 83' ' so as to control the rotation, in particular the rotational speed of each one of rotating bodies 71'' . In particular, in use, an increase of the rotational speed leads to an increase in the suction force and a decrease of the rotational speed leads to decrease of the suction force .

Thus, overall, in use, a suction force is applied on labels 2 retained on outer lateral surface 21 of transfer drum 20 of transfer device 7'' by suction source 23. In particular, suction force is generated through suction holes 30a, 30b, 30c by the suction generation units 35' ' .

In more detail, each suction generation unit 35' ' , in particular the respective functional group 68'' generates a suction force due to the evolution of the flow of air from the respective suction holes 30a, 30b, 30c to the respective air outlet portion 69' ' and, in particular, out of air outlet portion 69' ' . Even more particularly, the flow of air is generated by rotation of the respective rotating body 71'' . More precisely, rotation of each rotating body 71'' leads to the generation of a flow of air within the respective connecting channel 73' ' , in particular due to the drag forces between the air moved by the respective blades 71a'' of rotating body 71'' and the air present in the respective connecting channel 73' ' thereby resulting in the flow of air from suction holes 30a, 30b, 30c to the respective air outlet portion 69' ' . Preferably, the rotation, in particular the speed of rotation of each rotating body 71'' is selectively controlled by control unit 55' ' , in particular by cooperation with power supply unit 83' ' . Favorably, the speed of rotation is controlled in dependence of the suction force determined by sensor means 50 and a pre^¬ set (needed/desired) value so as to obtain the needed/desired suction force for retaining the respective label 2.

Overall, in this way, labels 2 received at receiving position 8 from cutting unit 12 are safely retained on respective retaining section 28 and are conveyed in a manner described in more detail above from receiving position 8 to application position 9, where they are applied on respective articles 3.

The advantages of label transfer device 7, 7', 7' 'according to the present invention will be clear from the foregoing description.

In particular, integrally mounting each suction generation unit 35 to the distributor plate 24 allows for reducing size and mass of label transfer device 7, 7', 7'' and accordingly of labeling apparatus 1 with respect to known label transfer devices and labeling apparatuses .

This is also the case for suction generation units

35' , 35' ' , which are at least partially integral parts of distributor plate 24'.

Additionally, suction generation units 35, 35' ,

35' ' lead to an overall reduction of the pipe and tubing works needed for applying suction on suction holes 30a,

30b, 30c with respect to the state-of-the art solutions. A particular advantage of transfer device 7'', in particular suction generation unit 35 ' ' is that solely electrical wiring 84'' is needed for controlling the suction force. This provides for a further reduction in the complexity of transfer device 7'', also with respect to transfer devices 7, 7'. In particular, suction generation units 35 ' ' do not require any compressed air and, accordingly, no tubing for the compressed air is needed. Additionally, no compressed air source is needed. As well, it is advantageous that the suction force is varied by simply changing the rotational speed of rotating bodies 71'' which increases the reactivity of the suction generation unit 35 ' ' .

Suction generation units 35 ' come along with a simple and straightforward way of adjusting the size of air conduits 44' allowing for easily and quickly tune the optimal performance and economy of the suction generation units 35 ' themselves.

Furthermore, suction generation units 35 , 35 ' generating suction by means of the Venturi effect and also suction generation units 35 ' ' come along with lower economical costs and facilitated maintenance approaches when compared to the state-of-the-art solutions which commonly use traditional vacuum pumps.

Clearly, changes may be made to label transfer device 7, 7', 7'' without, however, departing from the scope of protection as defined in the accompanying claims .

In an alternative embodiment of transfer device 7'' not shown, each air flow generation device would comprise a rotary body of the axial fan type arranged within the respective inner space and the respective air outlet portion would comprise a plurality of outlet holes provided on the periphery of the respective casing. In particular, the rotary body would divide the inner space into an upper portion being in direct fluidical contact with the respective air ports and a lower portion being in direct fluidic contact with the respective air outlet portion.

Claims

1) A label transfer device (7, 7', 7'') adapted to receive at least one label (2) at a receiving position (8) and to convey said label (2) along a path (Q) to an application position (9); the label transfer device (7, 7', 7'') comprising:

- a transfer drum (20) rotatable around a rotation axis (D) to define said path (Q) and delimited by an outer lateral surface (21) having a plurality of suction holes (30a, 30b, 30c) to retain said label (2) on the outer lateral surface (21) itself during transfer along said path (Q) ;

- a suction source (23) apt to exert a suction force on said label (2) through at least a fraction of said plurality of suction holes (30a, 30b, 30c) ; and

a stationary distributor plate (24) having at least one air port (25) configured to fluidically connect the suction source (23) to the plurality of suction holes (30a, 30b, 30c) ;

characterized in that the suction source (23) comprises at least one suction generation unit (35, 35' , 35' ' ) fluidically connected to said air port (25) and integrally mounted to the distributor plate (24) or being at least partially an integral part of the distributor plate (24') itself.

2) The label transfer device according to claim 1, wherein said air port (25) is part of a fluidic line configured to connect said suction holes (30a, 30b, 30c) to a discharge portion (37), and wherein said suction generation unit (35, 35' ) comprises a constricted section portion (38, 38') of said fluidic line so that the suction generation unit (35, 35' ) operates according to the Venturi effect.

3) The label transfer device according to claim 2, wherein the suction generation unit (35, 35' ) comprises at least one compressed air inlet (42) to feed compressed air into the constricted section portion (38, 38' ) .

4) The label transfer device according to claim 3, wherein the suction source (23) further comprises a pressure chamber (43, 43' ) interposed between the constricted section portion (38, 38') and the compressed air inlet (42) and a compressed air conduit (44, 44') for feeding the compressed air into the constricted section portion (38, 38') .

5) The label transfer device according to claim 4, wherein the pressure chamber (43, 43' ) surrounds the constricted section portion (38, 38') .

6) The label transfer device according to claim 4 or 5, wherein the suction generation unit (35' ) comprises adjustment means (61') for adjusting the size of the air conduit (44') .

7) The label transfer device according to any one of claims 4 to 6, wherein the air conduit (44, 44') has an annular configuration, in particular a truncated cone configuration.

8) The label transfer device according to any one of claims 4 to 7, wherein the air conduit (44, 44') is configured to guide compressed air into the constricted section portion (38, 38') so as to form a compressed air flow incident to a central axis (X) of the constricted section portion (38) of the fluidic line transversal to the distributor plate (24, 24') .

9) The label transfer device according to claim 8, wherein the compressed air flow, through the air conduit (44, 44'), forms an obtuse angle (a) with the central axis (X) of the constricted section portion (38) of the fluidic line towards the discharge portion (37) .

10) The label transfer device according to claim 9, wherein said obtuse angle (a) lies between 120° to 150°, preferably between 130° to 140°, most preferably around 135°.

11) The label transfer device according to any one of the preceding claims, wherein the suction generation unit (35, 35') comprises:

- a suction portion (46) having a tapered shape and placed adjacent to said air port (25) of said distributor plate (24, 24'); and

- a diffuser portion (47) having a tapered shape and placed adjacent to the discharge portion (37);

the constricted section portion (38, 38') being arranged between the suction portion (46) and the diffuser portion (47) and said suction (46) and diffuser portions (47) being tapered towards the constricted section portion (38, 38') .

12) The label transfer device according to claim 1, wherein the suction generation unit (35' ' ) comprises a functional group (68'') integrally mounted to the distributor plate (24) or being at least partially an integral part of the distributor plate (24') itself;

the functional group ( 68 '') comprising :

- an air outlet portion (69'') being in fluid connection with the suction holes (30a, 30b, 30c) and the air port (25) ; and

- an air flow generation device (70'') adapted to generate a flow of air from the suction holes (30a, 30b, 30c) to the air outlet portion (69'') through the air port (25) .

13) The label transfer device according to claim

12, wherein the air flow generation device (70'') comprises :

- a rotating body (71'') adapted to rotate around a rotation axis (E' ' ) and to generate the flow of air from the suction holes (30a, 30b, 30c) to the air outlet portion (69'') through the air port (25); and

an actuation device (72'') adapted to actuate rotation of the rotating body (71'') .

14) The label transfer device according to claim

13, wherein the air flow generation device (70'') further comprises a connecting channel (73' ' ) fluidically connecting the air port (25) and the air outlet portion (69''); and

wherein the rotating body (71'') is adapted to generate a flow of air within the connecting channel (73' ' ) for generating the flow of air from the suction holes (30a, 30b, 30c) to the air outlet portion (69'') through the air port (25) .

15) The label transfer device according to claim

13 or 14, wherein the functional group (68'') comprises a casing (76'') carrying the air outlet portion (69'') and having an inner space (77'') being in fluid connection with the air outlet portion (69'') and the air port (25); wherein the rotating body (71'') is arranged within the inner space (77'') . 16) The label transfer device according to any one of the preceding claims further comprising a control unit (55, 55'') for controlling the suction force applied by the suction generation unit (35, 35' , 35' ' ) .

17) The label transfer device according to claim 16 and according to any one of claims 1 to 11, further comprising :

- sensor means (50) adapted to generate a signal or signals related to the actual suction force applied by the suction generation unit (35, 35' ) ; and

pressure adjusting means (60) selectively actuated by the control unit (55) for adjusting the pressure of the compressed air fed to the suction generation unit (35, 35' ) as a function of the signal generated by the sensor means (50) .

18) The label transfer device according to claim 16 and according to any one of claims 12 to 15 comprising sensor means (50) adapted to generate a signal or signals related to the actual suction force applied by the suction generation unit (35' ' ) ; wherein the control unit (55' ' ) is adapted to control the actuation device (72'') for controlling the rotation of the rotating body (71'') for adjusting the suction force applied by the suction generation unit (35' ' ) .

19) The label transfer device according to any one of the preceding claims, wherein the suction generation unit (35, 35' , 35' ' ) is in direct contact with the distributor plate (24, 24') and is fluidically connected to the air port (25) without any further connecting means, in particular without tubing, pipes or hoses.

20) A label application apparatus (1) comprising at least one label transfer device (7, 7', 1'') according to any one of the preceding claims.