WO2026013558A1 - System for handling a sheet for packaging between successive workstations of a line for the production of boxes - Google Patents

Abstract

System (1) for handling a sheet (F) for packaging between successive workstations (S1, S2) of a line (100) for the production of boxes, comprising: - a main body (2) having an abutment plane (20) configured to receive in abutment a first face (F1) of the sheet (F) and leave accessible the opposite face; - movement members (4) configured to move the main body (2) between the workstations (S1, S2) of the line (100); - vacuum gripping members (3) mounted on the main body (2) and switchable between: - a gripping configuration in which, generating a depression, they grip on the first face (F1) so as to constrain the sheet (F) to the main body (2); - a release configuration in which they allow the detachment of the sheet (F) from the main body (2); - offset members (5) configured to reciprocally move the vacuum gripping members (3) and the abutment plane (20) of the main body (2) so as to be able to retain the sheet (F) by arranging it in: - an abutment position, in which the first face (F1) of the sheet (F) abuts against the abutment plane (20); - a raised position, in which the first face (F1) of the sheet (F) is raised by the abutment plane (20).

Description

System for handling a sheet for packaging between successive workstations of a line for the production of boxes

DESCRIPTION

Technical Field

The present invention relates to a system for handling a sheet made of packaging material such as, for example, corrugated cardboard or paper.

This handling system finds expedient use in lines for the production of packaging such as cardboard boxes.

State of the art

In the state of the art, lines for the production of boxes are known, that is, plants configured to receive as input a sheet of cardboard and, by performing a predetermined production cycle, return as output boxes for the packaging of products.

Lines for the production of boxes are divided into a plurality of workstations configured to perform respective phases of the aforesaid production cycle so that the sheet (or a portion thereof) passing through them in succession gradually takes on the conformation of a pre-formed or formed box.

The sheet is transported between workstations by means of special handling systems which, in order to ensure that the boxes are of good quality and correctly made, must be able to pick it up from one workstation and place it accurately in the next.

The importance of the correct and precise positioning of the work sheet is of particular importance between the printing station and the cutting station.

In this regard, it should be specified that it is often required to create graphic indications in predetermined regions of the box such as, for example, barcodes, content indications, aesthetic motifs and trademarks. In order for this information to be easily identified or quickly read by automatic systems, it is essential that its placement on the box is as precise as possible in relation to the design.

The sheet handling system between the workstations plays a fundamental role for the correct implementation of the graphic indications on the boxes. In fact, if the printed sheet is incorrectly or not precisely arranged in the cutting station, there is a real risk that the graphic indications will be in the incorrect region of the blank from which the box is obtained.

Disadvantageously, the known handling systems are not able to guarantee an accurate handling of the sheet between the workstations and, in particular, do not allow the sheet to be positioned precisely in the cutting station.

In detail, the known handling systems have a micro-perforated plane placed in fluid-dynamic connection with special vacuum generation members. The latter, when operated, generate a depression on the micro-perforated plane suitable for retaining the sheet adhered to it so as to allow its movement.

To deposit the printed sheet on the work plane of the cutting station, known handling systems require that the micro-perforated plane with the sheet adhered to it be brought into close proximity with the work plane so that the sheet is in abutment with the micro-perforated plane at the top and with the work plane at the bottom. Once this position is reached, the suction unit is deactivated and the micro-perforated plane raised with respect to the work plane.

It should be noted that, despite the deactivation of the suction unit, when the micro-perforated plane is moved away from the work plane, the sheet will tend to remain adhered to it and follow its ascending motion and then fall back on the underlying work plane. This inevitably affects the positioning of the sheet on the work plane and, consequently, the accurate placement of the graphic indications on the box.

It should also be noted that known handling systems necessarily require the perimeter regions of the work plane of the cutting station to be free, since the microperforated plane must be able to be brought into close proximity to the latter without encountering any geometric interference. This, in addition to involving an inconvenient oversizing of the cutting region, complicates its design and organization.

A further disadvantage of the known handling systems is that, in order to generate a sufficient depression on the entire micro-perforated plane, in particular if the sheet is smaller than the suction plane and therefore does not obstruct all the microholes of the aspiration plane, they require the use of suction units with high powers which therefore present a significant space requirement and cost.

Finally, it is noted that, although known handling systems are able to retain the sheet adhered to the aspiration plane in the direction orthogonal to the latter, due to the poor adhesion, unwanted displacements of the sheet on the aspiration plane could occur which, inevitably, would negatively impact the positioning accuracy of the sheet.

Since the known movement systems do not make it possible to guarantee sufficient handling precision, the lines for the production of boxes in which they are integrated have high production waste due, for example, to the incorrect positioning of the graphic indications.

Object of the invention

In this context, the technical task underlying the present invention is to propose a system for handling a sheet for packaging which obviates the drawbacks in the prior art as described above. In particular, an object of the present invention is to provide a system for handling a sheet for packaging capable of guaranteeing greater positioning accuracies than those of the systems known in the state of the art.

It is also an object of the present invention to provide a system for handling a sheet for packaging that is capable of moving the sheet by acting on only one of its faces without damaging it, in particular without deforming it.

A further object of the present invention is to provide a box production line with reduced production waste.

SUMMARY OF THE INVENTION

The technical task mentioned and the objects specified are substantially achieved by a system for handling a sheet for packaging in accordance with one or more of the appended claims.

In particular, the present invention proposes to provide a system for handling a sheet for packaging between successive workstations of a line for the production of boxes provided with offset members configured to arrange the sheet both in abutment and in raised position with respect to an abutment plane.

On the one hand, the arrangement of the sheet in abutment against the abutment plane allows it to be transported keeping it planar (i.e. without deforming/damaging it), on the other hand, the raised position of the sheet allows its precise deposition without running the risk of it remaining partially adhered to the abutment plane.

Therefore, the handling system that is the object of the present invention is able to achieve handling accuracies greater than those of the systems known in the state of the art and at the same time guarantee the flatness of the sheet.

The handling system that is the object of the present invention also makes it possible to reduce the dimensions and to simplify the construction/design of the cutting station. In fact, the offset members allow the sheet to be deposited on the work plane of the cutting station without the need to bring the main body into close proximity with the latter. In use, it will be sufficient to arrange the main body above the work plane and operate the offset members to move the sheet closer to the work plane so as to place it precisely on the latter.

The installation of the handling system that is the object of the present invention in a line for the production of boxes makes it possible to precisely move the sheets for packaging between the printing and cutting stations, thus minimising production waste due to incorrect positioning of the graphic indications on the boxes.

LIST OF FIGURES

Further characteristics and advantages of the present invention will become more apparent from the indicative, and therefore non-limiting, description of a system for handling a sheet for packaging and a line for the production of boxes employing such a system, as illustrated in the attached drawings in which:

- Figure 1 shows a top view of a line for the production of boxes according to the present invention;

- Figure 2 shows a perspective view of a system for handling a sheet for packaging (more simply, "handling system") according to the present invention, while supporting the sheet at a first station of the line of Figure 1;

- Figure 3 shows a side view of the handling system of Figure 2;

- Figure 4 shows a perspective view of the handling system of Figure 2 while depositing the sheet in a second station of the line of Figure 1;

- Figure 5 shows a perspective view of the handling system of Figure 2 in which the sheet is in an abutment position;

- Figure 6a shows a side view of the handling system with the sheet in the abutment position and with vacuum gripping members in a release configuration in which they do not retain the sheet;

- Figure 6b shows a sectional view of the handling system of Figure 6a taken along the section plane A-A,

- Figure 6c shows an enlargement of some details of Figure 6b;

- Figure 7a shows a side view of the handling system while placing the sheet in the abutment position and with the vacuum gripping members in a gripping configuration in which they retain the sheet along a gripping direction;

- Figure 7b shows a sectional view of the handling system of Figure 7a taken along the section plane B-B;

- Figure 7c shows an enlargement of some details of Figure 7b;

- Figure 8 shows a perspective view of the handling system of Figure 2 in which the sheet is in a raised position;

- Figure 9a shows a side view of the handling system while placing the sheet in the raised position and with the vacuum gripping members in the gripping configuration;

- Figure 9b shows a sectional view of the handling system of Figure 9a taken along the section plane C-C,

- Figure 9c shows an enlargement of some details of Figure 9b;

- Figure 10a shows a side view of the handling system while placing the sheet in the raised position and with the vacuum gripping members in the release configuration;

- Figure 10b shows a sectional view of the handling system of Figure 10a taken along the section plane D-D,

- Figure 10c shows an enlargement of some details of Figure 10b;

- Figure I la shows a side view of the handling system as shown in Figure 9a at the moment just before depositing the sheet;

- Figure 1 lb shows an enlargement of some details of Figure I la;

- Figure 11c shows a side view of the handling system as shown in Figure 10a when it has deposited and released the sheet;

- Figure l id shows an enlargement of some details of Figure 11c;

- Figure 12a schematically shows a side view of a second embodiment of the handling system according to the present invention while placing the sheet in an abutment position;

- Figure 12b shows schematically a side view of the second embodiment of Figure 12a while placing the sheet in a raised position;

- Figure 12c schematically shows a side view of a third embodiment of the handling system according to the present invention while placing the sheet in the abutment position;

- Figure 12d schematically shows a side view of the third embodiment of Figure 12c while placing the sheet in the raised position.

DETAILED DESCRIPTION

With reference to the attached figures, the present invention relates to a system 1 for handling (movement of) a sheet F made of a packaging material such as, for example, cardboard or paper.

Such a system 1 can for example be installed in a line 100 for the production of boxes so as to handle/transport the sheet F from which one or more boxes are obtained between successive workstations SI, S2.

In the context of the present invention, the terms "handling" and "movement" are used synonymously and include within their meaning various operations such as, for example, picking/depositing and transporting/overtuming of the sheet F. Furthermore, in the context of the present invention, "sheet" means a body with a predominantly two-dimensional (i.e. planar) extension, delimited on opposite parts by a first and a second face Fl, F2.

Referring to Figures 2 and 3, the system 1 that is the object of the present invention comprises a movable main body 2 that defines an abutment plane 20 on which the sheet F can be received in abutment.

This abutment plane 20 has a planar geometric conformation so that, when the sheet F is laid on it, it maintains its planar conformation.

In use, the abutment plane 20 is configured to receive in abutment the first face Fl of the sheet F and, at the same time, leave the second face F2 accessible. It should be noted that the abutment of the first face Fl on the abutment plane 20 allows the flatness of the sheet F to be guaranteed, while the access to the second face F2 allows one or more machining operations to be carried out on it (e.g. printing) and the sheet F to be deposited overturned on a working plane P (e.g. cutting plane).

The handling system 1 further comprises movement members 4 configured to move the main body 2 between successive workstations SI, S2 of the line 100 for the production of boxes.

In the embodiment shown in Figures 2 and 3, the movement members 4 comprise one or more guides 40 extending along a longitudinal direction X-X between successive workstations (e.g. from a printing station SI to a cutting station S2) and on which the main body 2 is slidably mounted. In use, the main body 2, sliding on the one or more guides 40 along the longitudinal direction X-X, moves between the workstations SI, S2 carrying the sheet F with it.

According to one aspect, the movement members 4 are configured to rotate the main body 2 around an axis of rotation R-R directed transversely to the longitudinal direction X-X so as to overturn the abutment plane 20. In use, by rotating the main body 2 around the axis of rotation R-R, the abutment plane 20 changes its orientation so that it can be selectively turned upwards (Figure 2) or downwards (Figure 4).

The rotation of the main body 2 about the axis of rotation R-R allows the sheet F to be supported with the second face F2 facing the upward so as to be able to perform a predetermined processing on it (e.g. printing) in a workstation SI (e.g. printing station) and deliver it overturned (i.e. with the second face F2 facing downward) in the next workstation S2 (e.g. cutting station).

In the embodiment shown in Figures 2 and 3, the movement members 4 comprise one or more support elements 41 on which the main body 2 is rotatably mounted. Preferably, each support element 41 is slidably mounted on the guides 40 along the longitudinal direction X-X.

According to one aspect, the movement members 4 comprise a first motor 43 configured to actuate the movement of the main body 2 along the longitudinal direction X-X and/or a second motor 44 configured to actuate the rotation of the main body 2 around the axis of rotation R-R.

The handling system 1 also comprises vacuum gripping members 3, mounted on the main body 2, configured to grip the sheet F so as to constrain it to the main body 2 and allow its movement with the latter.

Specifically, the vacuum gripping members 3 are configured to act on the first face Fl of the sheet F generating vacuum (i.e. reduction in pressure below atmospheric pressure) on it adapted to retain the sheet F along a gripping direction P-P directed transversely, preferably perpendicularly, to the abutment plane 20.

It should be noted that the suction generated by the vacuum gripping members 3 retains the sheet F not only along the gripping direction P-P directed orthogonally to the sheet F but, by friction, also along directions orthogonal to the gripping direction P-P lying in the plane of the sheet F. The vacuum gripping members 3, when operated, constrain the sheet F to the main body 2 so as to be integrally movable with the latter.

The vacuum gripping members 3 are switchable between a gripping configuration (Figures 7c and 9c), in which, generating vacuum, they are configured to grip the first face Fl of the sheet so as to retain it constrained to the main body 2 along the gripping direction P-P, and a release configuration (Figures 6c and 10c), in which they allow the detachment of the sheet F from the main body 2.

In use, the vacuum gripping members 3 are maintained in the gripping configuration both to allow the transport of the sheet F to the movement of the main body 2 and during a predetermined processing (e.g. printing) to ensure that the sheet F remains stationary.

Otherwise, after the sheet F has been transported from one workstation SI to the next S2, the vacuum gripping members 3 are switched from the gripping configuration to the release configuration to allow the deposit/delivery of the sheet F (Figure 11c), for example, on the work plane P of the next station S2.

It should be specified that, in the gripping configuration, the vacuum gripping members 3 are configured to generate a suction effect at least such as to prevent the detachment of the sheet F by the effect of the force of gravity when the main body 2 is overturned, i.e. it faces the abutment plane 20 downwards.

According to an aspect, the vacuum gripping members 3 comprise a plurality of gripping elements 30 configured to grip - or rather, exert a suction - on respective portions of the first face Fl. Advantageously, this makes it possible to distribute in several regions of the sheet F the force adapted to constrain it to the main body 2, thus reducing the risk of damaging the first face Fl of the sheet Fl during gripping.

Preferably, the gripping elements 30 are homogeneously distributed on the abutment plane 20 so as to exert a substantially homogeneous action on the sheet F regardless of its size and its placement on the abutment plane 20. In the embodiment shown in Figures 6c, 7c, 9c and 10c, each gripping element 30 comprises a suction cup 30a configured to abut against the first face Fl along the gripping direction P-P and, compressing, to grip on it generating a depression.

The use of the suction cups 30a is particularly advantageous as it allows the sheet F to be retained firmly both along the gripping direction P-P and along directions oriented perpendicular to the gripping direction P-P.

Each suction cup 30a has a cavity 30b configured to be brought to a pressure lower than atmospheric pressure and accessible through a mouth 30c. In use, the first face Fl of the sheet F is arranged to close the mouth 30c so as to be able to generate a depression inside the cavity 30b.

In the gripping configuration the suction cup 30a is compressed (contracted) along the gripping direction P-P, in the release configuration the suction cup 30a is instead relaxed along the gripping direction P-P so as to increase the volume of the cavity 30b with respect to the gripping configuration.

The handling system 1 also comprises offset members 5 configured to reciprocally move the vacuum gripping members 3 and the abutment plane 20 of the main body 2 so as to be able to retain the sheet F by arranging it at different distances (levels) from the abutment plane along the gripping direction P-P.

In particular, the offset members 5 are configured to retain the sheet F by arranging it in a abutment position, in which the first face Fl of the sheet F abuts against the abutment plane 20 along the gripping direction P-P, and a raised portion, in which the first face Fl of the sheet F is (at least in part) raised from the abutment plane 20 along the gripping direction P-P. In other words, in the abutment position the first face F 1 of the sheet F is arranged on the same level as the abutment plane 20 along the gripping direction P-P, while in the raised position the first face Fl of the sheet F is detached and spaced from the abutment plane 20 along the gripping direction P-P. When the sheet F is in the abutment position (Figures 7a, 7b and 7c), the abutment plane 20 provides an abutment that guarantees the flatness of the sheet F while the vacuum gripping members 3 fix the position thereof. This makes it possible to accurately perform one or more predetermined processes (e.g. printing) on the second face F2 and to transport the sheet F without the risk of damaging it.

When the sheet F is instead in a raised position (Figures 9a, 9b and 9c), being detached from the abutment plane 20, it is easily and precisely available on a working plane P of, for example, a cutting station S2. In fact, in the raised position, the sheet F, in addition to being brought into abutment on the work plane P, has the first face Fl separated from the abutment plane 20 and therefore is not affected by the adhesion forces with the latter.

It should be specified that the sheet F in both the abutment and raised positions is arranged parallel to the abutment plane 20.

It is also important to distinguish the raised position of the sheet F shown in Figures 8 and 9a-9c from the position of the sheet shown in Figures 6a-6c. In the latter, due to the physical bulk of the gripping elements 30 (of the suction cup type) in the release configuration, the sheet F is in fact raised from the abutment plane by a negligible amount which, in addition to making it difficult to grasp, does not make it possible to cancel the effects of the adherence condition due to the proximity of the abutment plane 20 to the first face Fl. The position of the sheet shown in Figures babe, different from that shown in Figures 8 and 9a-9c, is therefore considered comparable to the abutment position for the purposes of the present description.

Purely as an indication and example, in the condition shown in Figures ba-bc the first face Fl of the sheet F is spaced apart from the abutment plane 20 by an amount in the order of 0.5-1 cm, unlike the condition shown in Figures 8 and 9a-9c (raised position) the first face Fl of the sheet F is spaced apart from the abutment plane 20 by an amount greater than 5 cm, preferably between 10 and 30 cm.

It should be specified that the vacuum gripping members 3 can switch between the gripping and release configuration regardless of whether the sheet F is in the raised position or abutment position.

According to an aspect, the offset members 5 are configured to move the gripping elements 30 along the gripping direction P-P with respect to the abutment plane 20.

In particular, preferably, the offset members 5 are configured to switch the gripping elements 30 between a first position, in which they are substantially flush with the abutment plane 20 along the gripping direction P-P (Figures 6a-6c and Figures 7a-7c), and a second position in which they are spaced apart from the abutment plane 20 along the gripping direction P-P.

The gripping elements 30 in the first and second position are respectively configured to retain the sheet F by arranging it in the abutment and in the raised position.

According to one embodiment, the abutment plane 20 has a plurality of openings 20a associated with a respective gripping element 30.

In the first position the gripping elements 30 are arranged in the respective openings 20a.

In the second position the gripping elements 30 are extracted from the respective openings 20a so as to be spaced apart from the abutment plane 20 along the gripping direction P-P.

In the embodiment in which the gripping elements 30 are of the suction cup type, in the first position the gripping elements slightly protrude from the abutment plane 20 when the vacuum gripping members 3 are in the release configuration (Figures 6a-6c), and are arranged flush with the abutment plane 20 when the vacuum gripping members 3 are in the gripping configuration (Figures 7a-7c). The position slightly protruding from the abutment plane 20 makes it possible to ensure the full contact of the gripping elements 30 with the first face Fl of the sheet F and therefore the gripping thereof when the vacuum gripping members 3 switch from the rest configuration to the gripping configuration.

In the embodiment in which the gripping elements 30 are of the suction cup type, upon switching the vacuum gripping members 3 from the rest configuration to the gripping configuration, the suction cups 30a contract in the respective openings 20a along the gripping direction P-P until they are flush with the abutment plane 20 to arrange the first face Fl in contact with the latter.

In a first embodiment shown in Figures 6a-6c, 7a-7c, 9a-9c, and lOa-lOc, the offset members 5 comprise a plurality of actuators 50 each associated with a respective gripping element 30 and configured to move the latter along the gripping direction P- P so as to switch it between the first and second position.

Each actuator 50 can be pneumatically, hydraulically, electrically or similarly operated and, according to one embodiment, comprises a rod 50a movable along the gripping direction P-P and on the end portion 50b of which a respective gripping element 30 is mounted. Each actuator 50, by moving the rod 50a along the gripping direction P-P, switches the respective gripping elements 30 between the first and the second position to arrange the sheet F in the abutment position or raised position.

According to an aspect, the rod 50a has an internal channel configured to place a vacuum generation unit (not shown in the figures) in fluid communication with the relative gripping element 30. When the vacuum gripping members 3 are in the gripping configuration, the vacuum generation unit induces a depression in the gripping element 30 so that the latter can grip on the first face Fl of the sheet F in accordance with the above. It should be noted that in the first embodiment shown in Figures 6a-6c, 7a-7c, 9a-9c, each gripping element 30 is individually actuated by a respective actuator 50. In use, to move the sheet F parallel to the abutment plane 20 and thus avoid the formation of folds when switching from the abutment position to the raised position, it is important that the actuators 50 are operated simultaneously.

In a second embodiment shown schematically in Figures 12a and 12b, the offset members 5 comprise a movable crosspiece 51 on which the gripping elements 30 are mounted, and actuation means 52 configured to move the movable crosspiece 51 from and towards the abutment plane 20 along the gripping direction P-P.

It should be noted that the displacement of the movable crosspiece 51 from and towards the abutment plane 20 simultaneously moves the gripping elements 30 with respect to the abutment plane 20, switching them synchronously between the first and second position described above. Advantageously, this makes it possible to avoid the formation of folds or tears on the sheet F caused by the asynchronous movement of the gripping elements 30 which would tend to arrange different portions of the sheet F at different levels along the gripping direction P-P.

In a third embodiment shown schematically in Figures 12c and 12d, the offset members 5 are configured to move the abutment plane 20 with respect to the gripping elements 30.

The movement of the abutment plane 20 places the gripping elements 30 in different positions with respect to the latter. Thus, the movement of the abutment plane 20 along the gripping direction P-P simultaneously switches the gripping elements 30 between the first and second position.

It should be noted that in the third embodiment the gripping elements do not vary their position with respect to the main body 2 on which they are mounted. Therefore, advantageously, also the second embodiment makes it possible to avoid the formation of folds or tears on the sheet F caused by the asynchronous movement of the gripping elements 30.

According to one aspect, in the third embodiment the main body 2 comprises a first body 21 on which the gripping elements 30 are mounted and a second body 22 defining the abutment plane 20. In use, the offset members 5 are configured to move the second body 22 along the gripping direction P-P so as to change the position of the abutment plane 20 with respect to the gripping elements 30 and then switch the gripping elements 30 between the first and second positions.

In the second and third embodiments, the offset members 5 comprise, for example, actuation means 52 expandable/contractible along the gripping direction P- P.

In the second embodiment shown in Figures 12a and 12b, the actuation means 52 are interposed between the main body 2 and the movable crosspiece 51 along the gripping direction P-P so as to move the gripping elements 30 mounted on the movable crosspiece 51 with respect to the abutment plane 20 upon their expansion/contraction.

In the third embodiment shown in Figures 12c and 12d, the actuation means 52 are instead interposed between the first and second bodies 21, 22 along the gripping direction P-P so as to move the abutment plane 20 defined by the second body 22 with respect to the gripping elements 3 mounted on the first body 21 upon their expansi on/ contract! on .

It is also an object of the present invention to provide a line 100 for the production of boxes, for example according to the Box On Demand logic, employing the aforesaid handling system 1.

The line 100 that is the object of the present invention comprises a plurality of workstations S0-S3 arranged in succession to each other and configured to perform respective machining. The line 100 is configured to receive as input a sheet F made of packaging material and return as output a pre-assembled (pre-formed) or assembled (formed) box.

It should be specified that in the packaging sector, as in the context of the present invention, a pre-assembled/pre-formed box is intended to indicate the state of a "collapsed" box, which has a predominantly two-dimensional shape that facilitates its storage and handling before being filled.

It should also be noted that in the packaging sector, as in the context of the present invention, an assembled/formed box is intended to indicate the state, obtained from that of a pre-assembled box, in which the box has a predominantly three- dimensional shape to define an internal cavity suitable for accommodating one or more products.

With reference to Figure 1, the line 100 comprises a printing station SI configured to receive as input the sheet F, for example, from a magazine SO where a plurality of sheets F are stacked, and print on it predetermined graphic indications such as bar codes, indications of the contents of the box, instructions for transporting the box, logos, marks or any other graphic sign.

The sheet F is supplied at the entrance to the printing station with the first face Fl facing downwards and the opposite second face F2 facing upwards. Specifically, the sheet F is arranged on the main body 2 of the handling system 1 with the first face Fl resting on the abutment plane 20 and retained by the gripping members 3 in the gripping configuration. The second face F2 facing above is left accessible so that printing means 6 can act on it to make the aforesaid graphic indications.

According to one aspect, the printing means 6 comprise a printer 60 configured to make graphic indications on materials for packaging, and a printer movement system 61 configured to move the printer 60 in different regions of the second face F2.

The line 100 is provided with a control unit (not shown) configured to control the printer 60 and the movement system of the printer 61 to realize the graphic indications in specific regions of the second face F2.

Also with reference to Figure 1, the line 100 further comprises a cutting station S2 arranged downstream of the printing station SI and configured to cut from the sheet F one or more flat blanks representing the flat development of a box.

It should be specified that the cutting unit S2, upon command of the control unit, is configured to cut from the sheet F blanks of different form and geometry depending on the geometric characteristics of the box it is intended to make.

In use, the handling system 1 transports the sheet from the printing station S 1 to the cutting station S2, in which it is arranged with the first face Fl oriented above and the second face F2 oriented below (i.e. overtumed/inverted with respect to the printing station SI).

According to one aspect, the cutting station S2 is provided with a work plane P on which the handling system 1 is configured to arrange the sheet F with the second face F2 (the printed face) in abutment thereon.

The cutting station S2 comprises cutting means (not shown) and a cutting means movement system (not shown) controlled by the line control unit 100. In use, the control unit operates the cutting means and the relative movement system so that the blanks obtained from the sheet show the graphic indications made in the printing station SI in predetermined regions.

Still with reference to Figure 1, the line 100 further comprises a folding station S3, arranged downstream of the cutting station, adapted to receive the blank of the cutting station S2 and configured to realize the relative pre-assembled or assembled box by means of folding machining.

According to one aspect the folding station S3 comprises folding members (not shown in the figures) controlled by the control unit to act on the blank and fold predetermined portions thereof.

Clearly, in order to satisfy contingent and specific needs, a person skilled in the art may make numerous modifications and variants to the configurations described above. Such modifications and variations are all encompassed by the scope of protection of the invention, as defined by the following claims.

Claims

1. System (1) for handling a sheet (F) for packaging between successive workstations (SI, S2) of a line (100) for the production of boxes, said system (1) comprising:

- a main body (2) that is movable and defines an abutment plane (20) configured to receive in abutment a first face (Fl) of the sheet (F) and leave accessible a second face (F2) of the sheet (F) opposite the first face (Fl);

- vacuum gripping members (3), mounted on the main body (2), switchable between:

- a gripping configuration in which, generating a depression, the vacuum gripping members (3) are configured to grip the first face (Fl) so as to constrain the sheet (F) to the main body (2) along a gripping direction (P-P) directed transversely to the abutment plane (20);

- a release configuration in which the vacuum gripping members (3) allow the detachment of the sheet (F) from the main body (2);

- movement members (4) configured to move the main body (2) between the successive workstations (SI, S2) of the line (100) for the production of boxes; characterized in that it comprises offset members (5) configured to reciprocally move the vacuum gripping members (3) in the gripping configuration and the abutment plane (20) of the main body (2) along the gripping direction (P-P) so as to be able to retain the sheet (F) by arranging it in:

- an abutment position in which the first face (Fl) of the sheet (F) abuts against the abutment plane (20) along the gripping direction (P-P);

- a raised position in which the first face (Fl) of the sheet (F) is raised by the abutment plane (20) along the gripping direction (P-P).

2. System (1) according to claim 1, wherein:

- the vacuum gripping members (3) comprise a plurality of gripping elements (30) configured to grip respective portions of the first face (Fl);

- the offset members (5) are configured to switch the gripping elements (30) between:

- a first position in which they are substantially flush with the abutment plane (20) along the gripping direction (P-P) so as to be able to retain the sheet (F) by arranging it in the abutment position;

- a second position in which they are spaced apart from the abutment plane (20) along the gripping direction (P-P) so as to be able to retain the sheet (F) by arranging it in the raised position.

3. System (1) according to claim 2, wherein:

- the abutment plane (20) has a plurality of openings (20a) associated with a respective gripping element (30);

- in the first position the gripping elements (30) are arranged in the respective openings (20a);

- in the second position the gripping elements (30) are extracted from the respective openings (20a) so as to be spaced apart from the abutment plane (20) along the gripping direction (P-P).

4. System (1) according to any one of the preceding claims, wherein the offset members (5) are configured to move the gripping elements (30) along the gripping direction (P-P) with respect to the abutment plane (20).

5. System (1) according to claim 4, wherein:

- the offset members (5) comprise a plurality of actuators (50) each associated with a respective gripping element (30);

- each actuator (50) is configured to move the respective gripping element (30) along the gripping direction (P-P).

6. System (1) according to claim 4, wherein the offset members (5):

- comprise a movable crosspiece (51) on which the gripping elements (30) are mounted;

- actuation means (52) configured to move the movable crosspiece (51) from and towards the abutment plane (20) along the gripping direction (P-P) to jointly move the gripping elements (30) relative to the abutment plane (20).

7. System (1) according to claim 2 or 3, wherein the offset members (5) are configured to move the abutment plane (20) with respect to the gripping elements (30).

8. System (1) according to Claim 7, wherein:

- the main body (2) comprises;

- a first body (21) on which the gripping elements (30) are mounted;

- a second body (22) identifying the abutment plane (20);

- the offset members (5) are configured to move the second body (22) along the gripping direction (P-P) so as to change the position of the abutment plane (20) with respect to the gripping elements (30) along the gripping direction (P-P).

9. System (1) according to any one of claims 2 to 8, wherein each gripping element (30) comprises a suction cup (30a) configured to abut against the first face (Fl) along the gripping direction (P-P) and grip the first face (Fl) of the sheet (F) compressing and thus generating a depression on the first face (Fl).

10. Line (100) for the production of boxes, said line comprising at least: - a printing station (SI) adapted to receive as input a sheet (F) for packaging with a first face (Fl) facing downward and an opposite second face (F2) facing upward, said printing station (SI) being configured to print graphic indications on the second face (F2); - a cutting station (S2) arranged downstream of the printing station (SI) adapted to receive from the printing station (SI) the sheet (F) with the first face (Fl) facing upward and the second face (F2) facing downward, said cutting station (S2) being configured to cut said sheet (F) and obtain a flat blank representing the plane development of a box; - a folding station (S3) arranged downstream of the cutting station (S2) adapted to receive the blank from the cutting station (S2) and configured to make a pre-assembled or assembled box by means of folding machining; characterized in that it comprises a handling system (1) in accordance with any one of the preceding claims configured to move the sheet (F) between the printing station (SI) and the cutting station (S2) by changing the orientation of the faces.