TITLE: SHEET PLACING APPARATUS AND RELATED FEEDING DEVICE AND METHOD

FIELD OF APPLICATION OF THE INVENTION

This invention fits into the field of the sheet placing apparatuses for laying a cover sheet on palletized loads, in particular in a position higher than the load.

In particular, said sheet placing apparatus is arranged to operate in combination with automated winding machines for wrapping a palletized load.

BACKGROUND

Automatic winding machines for the packaging and the stabilization of palletized loads, i.e. articles stacked on loading pallets, are known to the state of the art.

This allows preserving the integrity of the load and facilitates the transport and storage of the articles.

The known winding machines can be of various types, for example with a rotating arm and fixed palletized load or with a fixed arm and rotating palletized load, or of another type.

The winding machines generally use stretch-type films to protect all or part of the vertical surface of the load.

When a more complete protection is required, these winding machines are combined with devices that apply cover sheets on the top of the palletized loads to be wrapped, so as to preserve them from external agents such as water or dust that could otherwise deposit and/or penetrate inside.

Furthermore, depending on the type of wrapping of the palletized load that can be of the anti-dust or waterproof type, the film is wound around the load in different ways, and also the cover sheet can consequently be applied at different moments.

Said devices that apply cover sheets can be integrated into the winding machine, or be autonomous and generally inserted before or after the load winding station.

In fact, a known anti-dust type winding mode involves first, the application of the cover film on the top of the palletized load, and then the winding of the film on the lateral surface of the entire load, in particular starting from the top and then descending towards the base.

On the contrary, an anti-water winding mode, provides that the film is wound from the base of the load and then ascending up to the top, and subsequently the cover film can be applied.

The film that laterally surrounds the load must be applied in such a way as to block the upper cover sheet firmly in place to prevent the penetration of external agents.

In fact, immediately after the application of the cover sheet, the load reaches the wrapping position inside the winding machine and on the top of the same load a presser integral with the load is positioned, which keeps the cover sheet in the correct position to block it.

Subsequently, a winding head, which supports a film reel suitable for wrapping the load sideways, is placed next to the load itself; the relative rotation between the winding head and the load causes the film, suitably pre-stretched, to be wound around the load according to the desired manner.

When the sheet placing apparatus is autonomous with respect to the winding machine, a reduction in working times is possible as it allows the times for inserting the cover sheet to be masked in the time for wrapping the palletized load preceding or following it.

In machines of known type, the upper cover sheet placing apparatus may comprise a portal structure or an anthropomorphic robot, capable of being placed over the palletized load, along the advancement line of said load through the machine.

The sheet placing apparatus is configured to unwind a sheet of predetermined length from a special reel generally supported in an elevated position, from which it cuts it to size and lays it on the top of the load itself.

For example, document EP0336517 describes a sheet placing apparatus supported by the frame itself of the winding machine itself and placed at a higher height than the palletized load. In particular, the film reel is positioned over the load, as well as the devices for feeding and towing the film always work in a position overlying the palletized load. This means that the maintenance, as well as the reel change, are in an uncomfortable position for the operator.

Furthermore, the replacement of the exhausted reel requires the complete stop of the machine generating long reel change times, with consequent reduced production efficiency of the sheet placing apparatus and of the entire wrapping cycle.

To this it must be added that the installation of the application device on a bulky portal structure imposes various restrictions from the point of view of the design of the machine layout.

In other machines of known type such as that described in EP 1717149, the cover sheet application device is mounted on a portal structure that provides that the film reel is over the movement means of the palletized load, but not over the palletized load itself.

With this solution, the maintenance and the replacement of the exhausted reel is at the height of the operator, therefore partly simplified.

This solution entails, however, safety problems due to the fact that the operator must perform these operations by walking on the movement means, such as roller conveyors or catenaries and not directly on the ground.

This solution also involves greater encumbrances on the ground in the layout of the machine: in more detail, in the event that the sheet placing device is installed over the transport line of the movement means, it is necessary to provide for sufficient spaces in the plant, and this obviously binds the plant designer to mandatory choices.

Furthermore, this solution does not make it possible to realize a transport line in which the palletized load can advance in both directions, since its path is blocked by the presence of the reel on the movement means.

Furthermore, even in this solution, the replacement of the exhausted reel requires the complete stop of the machine, generating long reel change times with consequent reduced production efficiency of the sheet placing apparatus and of the entire wrapping cycle.

EXPOSURE AND ADVANTAGES OF THE INVENTION

The technical problem underlying the present invention is to make available a sheet placing apparatus configured to lay a protective cover sheet over the palletized load that is structurally and functionally conceived to overcome one or more of the above limitations with reference to the above-mentioned prior art.

In the context of the aforesaid problem, a main aim of the invention is to develop a sheet placing apparatus that allows a solution accessible to the operator for maintenance and reel change that does not weigh on the overall dimensions of the apparatus and on its layout, allowing optimum management of the space available in the production plant.

It also allows the installation on existing packaging lines. A further object of the invention is also to make available to the technique a sheet placing apparatus within a simple, rational and efficient solution that allows a reel change that does not require stopping the working cycle of the apparatus itself.

These and other objects are reached by the features of the invention as set forth in the independent claims. The dependent claims outline preferred and/or particularly advantageous aspects of the invention.

In particular, the sheet placing apparatus object of the invention is configured to lay a protective cover sheet over the palletized load.

Said apparatus preferably comprises movement means suitable for supporting and/or moving the palletized load, a device for picking up and positioning the cover sheet and a feeding device.

Said feeding device in particular comprises a reel assembly configured to rotatably support a film reel.

A plurality of sheets can be obtained from said reel, by unwinding and cutting the film.

According to a preferred embodiment, said reel assembly is configured to be positioned in an operating position below the palletized load along the advancement line of said palletized load, by making available an edge of the film which comes out of the movement means to be grasped by the picking and positioning device which lifts said film from below to the top of the palletized load.

Thanks to this solution, the feeding means do not create encumbrances outside the advancement line of the palletized load. They are also at a height that is easily reachable by the operator.

Additionally, to facilitate the operator, the reel assembly is preferably configured to be extractable in an extracted position external to the movement means, preferably to the side of said movement means in which to perform the reel change.

Preferably, the feeding device is arranged such that the reel assembly is configured to have the reel with its axis of rotation orthogonal to the advancement direction of the palletized load.

Preferably, the feeding device cooperates with the picking and positioning device, so that said sheet is unwound, cut and picked up in a position in front of and/or behind the palletized load along its advancement line.

In a preferred embodiment, the feeding device comprises an additional reel assembly configured to rotatably support an additional film reel from which a plurality of said sheets can be obtained, by unwinding and cutting the film of said additional reel. Preferably the additional reel assembly is positioned in an operating position below the movement means and preferably in a position adjacent to the reel assembly.

In particular, the additional reel assembly is also configured to be extractable in an extractable position external to the movement means, preferably to the side of said movement means in which to perform the reel change.

Preferably the reel assembly and the additional reel assembly are configured to cooperate with the picking and positioning device one at a time.

In this way, the reel change does not affect the cycle time of the film placing apparatus, because a reel is always ready to be used when the one working is exhausted. In particular, also the replacement of the exhausted reel does not require the stop of the film placing apparatus as it is configured to continue to operate by means of the additional reel of the additional reel assembly placed in the operating position when the reel assembly is placed in the extracted position and vice versa.

To achieve the aforesaid aim in an easy way for the operator, preferably the reel assembly and the additional reel assembly comprises a carriage for moving from the operating position to the extracted position.

The feeding device installable on a sheet placing apparatus configured to lay a protective cover sheet over the palletized load is also the object of the invention.

The working method of the sheet placing apparatus is also the object of the invention. In particular, said method for laying a protective cover sheet over palletized loads provides for picking said cover sheet from a film reel placed below the palletized load along its advancement line; in particular, said reel being placed below the movement means suitable for supporting and/or moving the palletized load.

In particular, said method provides for grasping an edge of the film to make and lift the cover sheet to a position in front of and/or behind the advancement of the palletized load.

Preferably, the method provides for picking the film from a reel or from an additional reel placed side-by-side below the movement means. Said purposes and advantages are all achieved by the sheet placing apparatus and respective method for laying a protective cover sheet over the palletized load, object of the present invention, which is characterized by the provisions of the following claims.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features will be more apparent from the following description of certain embodiments illustrated by way of non-limiting example in the accompanying drawings.

- Figure la: Illustrates an axonometric view of a sheet placing apparatus with a reel assembly in the extracted position and a reel assembly in the operating position; - Figure lb: Illustrates an axonometric view of a reel assembly with detail of the retaining device;

- Figure 2a: illustrates a side view of the reel assemblies in the operating position with the swapping device in the working position and in the out-of-way position;

- Figure 2b: illustrates a detailed view of the swapping device in the working position with only one reel assembly in the operating position;

- Figure 3: illustrates a side view of a reel assembly in the operating position with a film retaining and cutting device in the working position;

- Figure 4: illustrates an axonometric view of a reel assembly in the operating position with a device for retaining and device for picking and positioning the film in the working position;

- Figure 5: illustrates a different axonometric view of a picking and positioning device of the sheet placing apparatus.

DESCRIPTION OF THE INVENTION

With particular reference to the figure, there is represented a sheet placing apparatus 100 configured to lay a protective cover sheet 510 over the palletized load 500.

The palletized load 500 also referred to as pallet, generally comprises a support pallet 501 on which a plurality of products are stacked.

Said apparatus 100 preferably comprises movement means 10 suitable for supporting and/or moving the palletized load 500.

As is known to a person skilled in the art, said movement means 10 can be, for example, roller conveyor or catenary type. The type of the movement means 10 generally depends on the conformation of the type of pallet 501, as well as on the type of stacked products and on their stability. In the figures and in the description, we will often refer to roller conveyor-type movement means 10. It is understood, however, that the same considerations can be developed in relation to movement means 10 of a different type, such as with catenary.

Said sheet placing apparatus 100 may comprise a picking and positioning device 20 for the cover sheet 510.

Said device 20 can be configured in different ways. In fact, it can provide a portal structure, a column structure, or alternatively an anthropomorphic robot structure.

Said device 20 must be able to place itself over the palletized load 500 on which the cover sheet 510 is to be placed.

Said sheet placing apparatus 100 may further comprise a feeding device 30 comprising a reel assembly 31 configured to rotatably support a reel 520 of film 530.

A plurality of said sheets 510 can be obtained from said reel 520, by unwinding and cutting the film 530. In fact, the reel assembly 31 is configured to allow the film 530 to be unwound from the reel 520 by exerting a traction on an edge 511 of the film 530; once a length of film 530 sufficient to cover the load 500 has been unwound, the film 530 is cut, for example by cutting means 40.

Said cutting means 40 may, for example, comprise a glow wire 41 which, by coming into contact with the film 530, cuts it, as represented in the figure.

Said cutting means 40 may, for example, comprise means for translating the glow wire 41 between a position in which it contacts the film 530 to make the cut and a position away from said film 530 once the cut is made.

The cover sheet 510 thus made can be picked up by the picking and positioning device 20 for depositing it on the palletized load 500. A preferred embodiment provides that said reel assembly 31 is configured to be positioned below the palletized load 500, when in the operating position O.

In fact, the operating position O refers to the position of the reel assembly 31 such as to ensure that the apparatus 100 is in working condition.

The position of the reel assembly 31 in particular provides that it is positioned below the palletized load 500 and along the advancement line of said palletized load 500.

In particular, the reel assembly 31 is preferably positioned below the movement means 10, as represented in the figure.

This makes it possible to hide the encumbrance of the feeding device 30 in the encumbrance of the movement means 10 without creating additional encumbrances of the apparatus 100.

From said position of the reel assembly 31, below the palletized load 500, the edge 511 of the film 530 that comes out of the movement means 10 is made available.

In the figure, for example, the edge 511 comes out between one roller and the other of the roller conveyor on which the pallet 500 moves.

Said edge 511 in particular comes out in a position suitable for being grasped by the picking and positioning device 20 arranged to lift said film 530 from below to the top of the palletized load 500.

According to one aspect of the invention, the feeding device 30 is arranged such that the reel assembly 31 is configured to have the reel 520 with its axis of rotation X orthogonal to the direction of advancement of the palletized load 500.

In particular, the feeding device 30 cooperates with the picking and positioning device 20 so that said sheet 510 is unwound, cut and picked in a position in front of and/or behind the palletized load 500 along its advancement line

Preferably, the picking and positioning device 20 is suitable for grasping said edge 511 of the film 530 and cooperates with the feeding device 30, so that said sheet 510 is unwound, cut and picked in a position in front of and/or behind the palletized load 500 along its advancement line.

The figures represent a palletized load 500 that advances on the movement means 10. In the representation, the feeding device 30 is placed downstream of the load 500 that enters the working area of the apparatus 100.

Therefore, in the operating step said load 500 stops before passing past the feeding device 30.

The picking and positioning device 20 grasps said edge 511 from the reel 520 in a position in front of the load 500 and unwinds the film 530 cooperating with the feeding device 30 in order to make the sheet 510.

The picking and positioning device 20 lifts the sheet 510 as far as the edge 511 is brought over the load. At this point the relative translation towards each other of the picking and positioning device 20 and of the load 500 causes the sheet 510 to be rested on the top of the load.

In the figures there is represented a preferred embodiment that provides for the load 500 to be translated and not the picking and positioning device 20.

Once the load 500 is in the correct position, the picking and positioning device 20 thus releases the edge 511 by depositing the sheet 510 on the top of the load 500.

In order to facilitate the reel change 520, a preferred embodiment provides that the reel assembly 31 is configured to be extractable in an extracted position E external to the movement means 10.

Preferably said extracted position E is to the side of said movement means 10 in which to perform the reel change 520.

In this way, the operator does not have to climb up to a raised position to perform the reel change or he must not climb onto the movement means 10, but he can remain on the ground which makes the reel change 520 comfortable and easy.

In particular, the feeding device 30 may comprise an additional reel assembly 32 configured to rotatably support an additional reel 521 of film 530.

A plurality of said sheets 510 can also be obtained from said reel 521, by unwinding and cutting the film 530 of said additional reel 521.

Like for the reel assembly 31, preferably the additional reel assembly 32 is positioned in an operating position O below the movement means 30 and preferably in a position adjacent to the reel assembly 31.

Similarly preferably, also the additional reel assembly 32 is configured to be extractable in an extracted position E external to the movement means 10 and preferably to the side of said movement means 10 in which to perform the change of the reel 520.

For example, the additional reel assembly 32 may be in the extracted position E, while the reel assembly 31 is in the operating position O, or vice versa. Said groups 31, 32 may also be both in the extracted position E or both in the operating position O.

In accordance with a formulation of the present invention, the additional reel assembly 32 is configured to be operational alternately with the reel assembly 31, i.e., they are configured to cooperate with the picking and positioning 20 one at a time.

Thus, the two reel assemblies 31 and 32 can both be in the operating position O, but only one at a time is enabled to cooperate with the picking and positioning device 20, as will be better described below. A preferred embodiment provides that the film placing apparatus 100 is configured to continue to operate through the additional reel 521 of the additional reel assembly 32 placed in the operating position O when the reel assembly 31 is placed in the extracted position E and vice versa.

Thanks to this solution, it is possible for the apparatus 100 to continue working with, for example, the reel assembly 31, while the additional reel assembly 32 is in a phase of reel change or in a maintenance phase. Conversely, the apparatus 100 can continue to work with the additional reel assembly 32, while the reel assembly 31 is in a phase of reel change or in a maintenance phase. This solution allows the apparatus 100 not to be affected by the time for changing the reel 520 or 521 and to continue working without being detrimental to its efficiency.

Preferably, the sheet placing apparatus 100 comprises protection elements 36 that can be configured to allow during the extraction of the reel group 31 or of the additional reel group 32 that the apparatus 100 remains safe and continues the work cycle.

These protection elements 36 can be, for example, more or less shaped casings that prevent the operator from being able to come into contact with the moving parts of the apparatus 100 during its operation.

In accordance with possible embodiments, the reel assembly 31 and the additional reel assembly 32 each comprise at least one carriage 310, 320 for moving from the operating position O to the extracted position E.

In particular, said carriages 310, 320 may comprise wheels 311, 321, to facilitate sliding and correct positioning.

Said wheels 311, 321 preferably cooperate with guide elements 312, 322. In the figure there is represented a possible embodiment that provides for pairs of wheels 311a, 321a, placed at the two ends of the reel assembly 31, 32.

Preferably said pairs of wheels 311a, 321a, are configured to cooperate with tubular-shaped guide elements 312, 322 fixed to the ground below the movement means 10.

A preferred embodiment provides that said carriages 310, 320 comprise a further pair of additional wheels 311c, 321c arranged to the side of extraction of the reel assembly 31, 32.

Thanks to said additional pair of wheels 311c, 321c, the carriages 310, 320 can be pulled out while remaining in a horizontal position even when the first pair of wheels 311a, 321a is no longer resting on the guide elements 312, 322.

Said pair of additional wheels 311c, 321c is for example configured to rest on the ground or for example to cooperate with guide elements 312, 322 made of bent sheet metal, which is arranged on the ground and which acts both as a sliding plane and as a guide for the wheels 311c, 321c.

In particular, as represented in the figure, said guide elements 312, 322 made of bent sheet metal are positioned in the area outside the movement means 10.

However, it is understood that alternative solutions known to a person skilled in the art and any variations in detail that may be necessary for technical and/or functional reasons, are considered as of now to fall within the same protective scope.

A preferred form also provides that the carriages 310, 320 comprise gripping means 313, 323, e.g. grips or handles that help the operatorto intervene on the reel assemblies 31, 32 when moving from the operating position O to the extracted position E. Therefore, said carriages 310, 320 define reel assemblies 31, 32 that are configured as real guided carriages.

Said reel assemblies 31, 32 may further comprise blocking elements for blocking them in the operating position O and having the certainty of having correctly positioned the reel 520, 521.

According to one aspect of the invention, the reel assembly 31 and the additional reel assembly 32 respectively comprise a first and a second retaining device 33, 34 of the film 530.

Preferably said first and second retaining devices 33, 34 are configured to cooperate with the respective reel 520 or the additional reel 521 to retain the edge 511 of the film 530.

In the figures there is represented a possible embodiment of said first and second retaining devices 33, 34 comprising respectively a first and a second support element 333, 343 on which a plurality of wheels 331, 341 and counter wheels 332, 342 are mounted. Preferably said wheels 331, 341 are opposed to the counter wheels 332, 342 and are preferably kept in contact with them by elastic means so as to retain the film 530 interposed between said wheels 331, 341 and counter wheels 332, 342.

In accordance with a feature of the invention, said first and second retaining devices 33, 34 are configured to assume at least a working position LI and an out- of-way position L2.

In particular, said working position LI provides that the edge 511 of the film 530 is in a position in which it can be grasped and lifted by the picking and positioning device 20.

In particular, when the first retaining device 33 is in the working position LI, the second retaining device 34 is in the out-of-way position L2 and vice versa.

Thus the first and second retaining devices 33, 34 do not interfere with each other. This allows to always have a reel in use. Therefore, when the reel assembly 31 is in the operating position O and the reel 520 is working, the reel assembly 32 may be in the operating position O, but the additional reel 521 is not working; said additional reel 521 may be ready to be used as an alternative to the previous one, for example when the reel 520 is exhausted.

Conversely, in the case in which the additional reel 521 is working.

The picking and positioning device 20 is operatively connected to the retaining device 33, 34 for lifting the sheet 510 by grasping the edge 511.

For example, a column-type picking and positioning device 20 is shown in the figure comprising a lifting column 21 configured to translate vertically an arm 22 on which a plurality of hooking elements 23 are installed which are positioned so as to be interposed between said wheels 331, 341 to grasp the edge 511.

Said edge 511 can be grasped, for example, by hooking elements 23 of a type known to a person skilled in the art, such as pneumatic or electrical grippers, or by means of suction systems that work with the vacuum.

The arm 22 is configured to be able to be inserted between the movement means 10 for example between one roller and the other.

As represented in the figure, preferably the support element 333, 343 is movable between the out-of-way position L2 and the working position LI by rotation about an axis X' parallel to the axis X of rotation of the reel 520, 521.

In accordance with a feature of the invention, a preferred form provides that the feeding device 30 comprises a swapping device 35 configured to cooperate, when the reel groups 31, 32 are in the operating position (O), with the first and/or the second retaining devices 33, 34.

In particular, said swapping device 35 is configured to bring the first and/or second retaining devices 33, 34 simultaneously from the out-of-way position L2 to the working position LI.

Thanks to said swapping device 35, it is possible to have one or the other reel 520, 521 work depending on the operational needs.

Said swapping device may provide actuation means 351 such as of the motorized, pneumatic, hydraulic type, etc. configured to act on the retaining devices 33, 34.

A possible embodiment represented in the figure provides that said swapping device 35 further comprises a translating element 352 driven by the actuation means 351 configured to cooperate with the support elements 333, 343 for their rotation about the axis X'. The feeding device 30 made according to the previous features is also the object of the invention.

Said feeding device 30 is installable on a sheet placing apparatus 100 configured to lay a protective cover sheet 510 over the palletized load 500.

Therefore, it is also possible to install the feeding device 30 in already existing sheet placing devices 100.

The working method of the sheet placing apparatus 100 is also the object of the invention.

In particular, said method for laying a protective cover sheet 510 over palletized loads 500 provides for picking said cover sheet from a reel 520, 521 of film 530 placed below the palletized load 500 along its advancement line; in particular, said reel 520, 521 being placed below the movement means 10 suitable for supporting and/or moving the palletized load 500.

Said method provides for grasping an edge 511 of the film 530 to make and lift the cover sheet 510 to a position in front of and/or behind the advancement of the palletized load 500.

Preferably, the method provides for picking the film 530 from a reel 520 or from an additional reel 521 placed side-by-side below the movement means 10.

This allows not to stop the work operations of the apparatus 100, when one of the two reels 520, 521 runs out.

In fact, said method provides at the end of the film 530 of the reel 520 or of the additional reel 521, for replacing said empty reel by pulling it out to the side of the movement means and preferably without stopping the work cycle. It is understood however that what is described above has a value of non-limiting example, therefore, possible variants of detail that may be necessary for technical reasons and / or functional, are considered as of now falling within the same protective scope defined by the claims indicated below.