IT201900001197A1 - Hooding machine with film change - Google Patents

Description

Description of the patent application for industrial invention entitled "Hooding machine with film change"

The present invention refers to a machine of the type called "hooding machine", that is, a machine that packs a package by inserting a plastic film cap from the top (generally of extensible or heat-shrinkable material).

Known hooding machines take the film from a feed reel and cyclically cut it transversely, weld it to form a piece of tube or "cap" and drag it along a feed path until it is brought with the mouth facing downwards. an insertion head. The insertion head radially expands the cap over the pack to be packaged and then translates vertically downwards so as to fit the cap onto the pack and complete the packaging.

In a particular type of these machines, the insertion head can also curl the cap along its longitudinal axis to accommodate it all on the head and then unroll it on the pack as the head is lowered. To facilitate the production of the cap, the film is often already shaped in the form of a continuous flattened tube rolled up on the supply reel, so that to form the cap it is sufficient for the machine to cut and transversely weld a piece of the unwound film and expand the tube radially.

In known machines, the change of film (i.e. the replacement of one reel of film with another) involves a rather long machine stop. If frequent changes have to be made, due for example to the need to pack limited sequences of packs with the same film and then switch to a different film (for example, a film different in color, format, physical characteristics, surface printing, etc. ), it often becomes advantageous, from a time point of view, to use different machines with the various films, rather than a single machine in which to replace the film reel.

This naturally entails considerable additional costs both for the need for additional machines and for the complication of the lines for transporting the packs to and from the various machines.

The general purpose of the present invention is to provide a hooding machine which allows to use different reels of film in a simple and rapid way.

In view of this purpose, according to the invention, it was thought to produce a hooding machine comprising a receiving area for a pack to be hooded and a hooding head to which a strip of film, intended to form a hood to be fitted on the package , is fed starting from an initial zone of a feeding path towards the capping head, characterized in that it comprises: a magazine with a carousel which supports a plurality of film reels and which is movable to alternatively carry one of the film in an operational position; a dispensing device associated with each reel of film and which receives a free end of the film of the associated reel, the carousel comprising receiving seats for each dispensing device; a transfer device which moves between a first and a second position and is suitable:

- in the first position to withdraw from one of said reception seats a dispensing device with the free end of the associated reel film which is in the operating position;

- in the second position to move said dispensing device in correspondence with the initial zone of the feeding path to feed the film of the reel in said operative position to said path.

To clarify the explanation of the innovative principles of the present invention and its advantages with respect to the known art, an exemplary embodiment applying these principles will be described below, with the help of the attached drawings. In the drawings:

-figure 1 represents a partially sectioned schematic side elevation view of a hooding machine according to the invention;

figure 2 represents an enlarged schematic view of an area of the machine of figure 1 with a transfer device;

figure 3 represents a schematic lateral and partially sectioned view of a device for dispensing the film of the machine of figure 1; figure 4 represents a schematic front elevation view of the dispensing device of figure 3 in a rest position;

figure 5 represents a partial, enlarged, lateral schematic view of the transfer device of figure 2 in a position for withdrawing the dispensing device from its rest position;

figures 6 and 7 show schematic front elevation views of the transfer device during movement of the dispensing device;

figure 8 represents a view of the machine of figure 1 during an operation phase;

Figures 9 and 10 show schematic views of a possible engagement / disengagement mechanism, respectively in engagement and disengagement position. With reference to the figures, figure 1 shows a hooding machine, generically indicated with 10, made according to the invention.

The machine 10 comprises a system 11 for forming a cap 60 starting from a strip of film wound on a reel and arriving from a magazine 12.

Preferably, the film strip can already be formed in the form of a tube in a flattened condition, which is transversely extended in the machine so that it can be fitted onto a pack to be packaged.

Usually, the film tube in its flattened condition has side edges that are folded inwards like a bellows, so as to form four lateral edges on the edges. This conformation of the tube of film rolled on a reel is well known in the art and will therefore not be further described or shown here.

Alternatively, the film tube can be formed directly in the machine by folding and longitudinal sealing of a film strip wound on a reel, again according to a technique well known to the expert and which will therefore not be further described or shown here. In this case, the cap forming system 11 will comprise known means for folding the film strip in half along its longitudinal extension to face its lateral edges and means for sealing together said two lateral edges, so as to obtain the tube of movie. These means are also well known to those skilled in the art and will not be further described or shown here.

In any case, the cap formation system 11 advantageously comprises gripping and drawing devices 13 which move along a feed path 14 starting from an initial zone 15 of the path, where the film arriving from the magazine 12 has a its initial flap, as will be clear from the following.

The gripping and dragging devices can for example comprise suitable grippers for gripping the film and a motorized chain conveyor system for moving these grippers along the path 14.

The feed path 14 has a final zone 16 where there is a head 17 for fitting the cap onto a pack 18 and which is arranged over a zone 19 of the machine which receives the pack 18 to be capped.

The package can arrive in the reception area 19 transported manually or a known transport system 20 such as for example a conveyor belt can be provided.

As can be seen in Figure 1, the path 14 is preferably shaped generically as an inverted L or J, with a first vertical section upwards, a second horizontal section and, preferably, a third short vertical section downwards which reach the head 17.

The head 17 is of a per se known type and will not be shown or described in detail, as it can be easily imagined by the technician on the basis of the description made here. For example, the head 17 is suitable for receiving the cap from the gripping and pulling means, expanding it transversely and fitting it onto a package located in the receiving area 19.

The head 17 can advantageously be of the known type which curls and accumulates the film tube on itself, cut into a segment of sufficient length to cover the pack, before moving downwards and unrolling it along the height of the pack (such as schematically shown in broken lines in figure 1).

For example, the head 17 may comprise a horizontal rectangular frame 21 intended to be arranged on the sides of the pack and with at least four edges that can be removed on command to fit inside the cap and spread it transversely to be able to fit it on the pack. Motorized rollers (not shown in detail) can curl the cap along its longitudinal extension to bring it all over the frame and then unwind it onto the pack as the frame moves down around the pack.

In the initial area 15 of the path 14 there is a known device 33 for transversal cutting of the film strip and for possible transversal sealing of the tube downstream of the cut, to form a tube segment which constitutes a cap.

The machine can also have the cap forming system 11 and the head 17 suitable for adapting to different film formats (i.e. transversal dimensions of the cap) fed to the initial zone 15. In particular, the transverse dimensions of the path 14 may vary for example by means of the transversal distancing of the guides and the head will be able to expand accordingly, as per se known to the skilled person

By way of example, the parts of the cutting and sealing, film transport and capping machine 10 can be generically of the known type and described in patent application EP 3,335,998, even if other known systems can always be used.

According to the present invention, the magazine 12 comprises a carousel 22 which supports a plurality of film reels 23 and which is movable to alternatively bring one of the reels into an operative position. For example, the carousel is advantageously rotating around a horizontal central axis 24 by means of an electric motor 25. As can be seen in figure 1, the film reels (for example three) are supported with their axis 26 arranged horizontally and are equally distributed on the carousel (for example around the rotation axis 24). A motor device 27 is operable to rotate a reel which is brought into the operating position by means of the movement of the carousel 22. For example, in the machine shown the reel in the operating position is the one at the top right in Figure 1.

The motor device 27 may comprise for example a motorized roller 28 which is pushed on command by means of an actuator 29 against the periphery of the reel which is in the operative position.

In figure 1 the motor device is shown in its rest position, that is to say with the motorized roller which is moved away from the periphery of the reel.

A film delivery device 30 is associated with each reel 23 and receives the free leading edge of the film rolled up in the associated reel, as will be further clarified below. Each dispensing device 30 has its own receiving seat 31 on the carousel.

The machine 10 also comprises a transfer device 32 which is motorized to move on command between a first position close to the initial area 15 of the path 14 of the film towards the head 17 and a second position close to the seat 31 for receiving the dispensing device 30 of the film. coil at that time in the operating position. Figure 2 shows in greater detail the area of the machine with the transfer device 32. In this figure, a possible embodiment of the transfer device with its movement system is shown between the position (shown in solid line) next to the zone 15 and the position (shown in broken lines) close to the seat 31 for receiving the dispensing device 30 of the reel 23 which is at that moment in the operative position.

In the embodiment shown, the transfer device 32 comprises a gripping head 35 for the dispensing device 30 and a motorized mechanism 36 (for example a motorized parallelogram mechanism) for moving the head 35 between said two positions.

The gripping head 35 also comprises an actuator 37 (for example formed by two lateral linear actuators) for the vertical movement of the head 35 and for hooking and vertically moving the dispensing device, as will be clear from the following.

Figure 2 also shows in greater detail the transversal cutting and sealing device 33 and the grippers 34 of the gripping and dragging means 13 which are designed to grip a leading edge of the film to transport it along the path 14 to the head 17.

For greater clarity, Figure 3 shows a possible embodiment of a dispensing device 30. In this embodiment, the device 30 comprises a body 40 with a return roller 41 placed at a lower inlet end and onto which the strip 42 reaches. of film coming from the corresponding reel 23. The strip of film 42 deflected by the roller 41 passes into a guide passage 43 in the body of the device 30 and exits from the opposite upper end 44 with the two faces 42a and 42b of the film tube slightly offset one from the other so that they can be taken in proximity of their lateral edges by corresponding four grippers 34 of the gripping and dragging means 13 when the dispensing device 30 is carried by the transfer device 32 in correspondence with the initial area 15 of the power supply 14.

As shown schematically in Figure 3, in the rest position of the dispensing device 30, that is to say when it is in its seat 31 in the magazine, the strip 42 protrudes only slightly above the device 30 with a leading edge of the film.

In figure 4 the dispensing device 30 is shown schematically from the front (that is to say from the right in figure 3) and inserted in its seat 31 in the carousel 22. The seat 31 includes on the carousel some couplings 45 to removably accommodate the opposite ends 46 , 47 of device 30.

Figure 5 shows in greater detail the interaction between a dispensing device 30 in its seat 31 on the carousel and the transfer device 32. Figure 5 also shows a film blocking pad 50 which is present in the seat 31 to stop the flap free of the film when the dispensing device 30 is in its seat 31.

As can also be seen in Figure 5, when the transfer device is moved to its position close to the seat 31, the head 35 is located under the delivery device. In this way, when the head 35 is moved upwards by the actuator 37 it engages the dispensing device, releases it from its seat 31 and removes it from the carousel. This is also visible in the front view of figure 6, where the dispensing device 30 is shown unhooked from the couplings 45 of its seat 31 and taken over by the head 35 of the transfer device 32 which supports the dispensing device 30 from its two opposite ends. 46 and 47.

Figure 7 shows the front of the dispensing device 30 moved by the transfer device 32 to the position close to the initial zone 15 of the feed path 14 of the cap.

Once the transfer device has brought the dispensing device 30 to this position under the initial zone 15 (as shown with a solid line in figure 7), the actuator 37 raises the dispensing device so as to bring it closer to the initial zone 15 (as shown in solid line in figure 7). shown in broken line) and thus allow the grippers 34 of the transport system to grasp the free edge of the film to transport it towards the capping head 17.

Figure 8 shows the machine during an operating phase of capping.

To facilitate the unwinding of the film during its dragging along the path 14, the motor device 27 is moved to its operative position and controls the rotation of the reel.

Once the amount of film necessary to form a cap has passed through the means 33, these means are operated to separate the cap and possibly seal the bottom thereof. A new initial edge of the film is thus ready in the initial area 15 for a subsequent capping operation.

The hood formed by the separated film strip is taken over by the hooding head 17, which opens it and fits it on the pack, as shown in figure 8. The head 17 can also employ suitable air jets to inflate the hood and facilitate it. introduction onto the pack, according to a per se known technique.

Once the pack is hooded and the head has returned to its raised position, the pack can be removed from the receiving area 19 of the machine and replaced by a new pack to be hooded and the capping operations can be repeated with the new pack. The cap can also possibly be heat-shrunk by means of the head 17, if this function is provided (for example with thermal heaters on the head 17 which retract the cap during the upward return movement of the head).

If it is necessary to use a film of a different reel among those in the magazine 12, then the transfer device 32 will return the dispensing device 30 in use to the corresponding seat 31 on the carousel 22 and re-attach it to the seat and then withdraw.

The motor device 27 will be moved to allow the carousel 22 to rotate and bring the desired different reel 23 into the operative position. The loading operations of the new film will then be repeated the same as described above for the previous reel and the capping operations will be able to resume with the new film.

By way of example, figures 9 and 10 schematically show in greater detail a possible embodiment of the clutches 45, made with a spring and with an unlocking actuator 61 arranged on the pick-up head 35 for controlling their disengagement. For simplicity, the coupling on the left side of the dispensing device and of the withdrawal head 35 is shown, but the same structure will advantageously also be present on the opposite side. In particular, as can be seen in figure 9, the couplings 45 can comprise on each of the two ends 46 and 47 of the delivery device 30 at least one coupling bolt 62 elastically pushed outwards by springs 63.

Each seat 31 on the carousel comprises corresponding housings 64 for receiving the coupling latches 63, so that each bolt 62 enters the corresponding housing 64 when a dispensing device 30 is placed in its corresponding seat 31 and the dispensing device 30 is thus constrained to its seat 31, as can always be seen in figure 9.

If a locking of this type is also desired for the dispensing device in the operative position in the zone 15, corresponding housings 64 can also be provided in the zone 15 which receives the ends 46, 47 of the dispensing device 30 in operating condition. When the head 35 receives and supports the dispensing device 30, the release actuator 61 is brought in correspondence with the bolt mechanism and is operable to move the bolt towards the disengagement position against the action of the springs and release it from the corresponding housing 64, as shown in figure 10. The transfer device can thus freely move the dispensing device as already described above.

At this point it is clear how the purposes of the invention have been achieved. With a machine according to the invention it is possible to quickly and automatically switch from one film reel to another so as to be able to use different films (by color, size, print, physical characteristics, etc.) according to the needs of the moment. For example, reels with films of different formats can be inserted in the magazine so that the machine can quickly adapt to the format of the pack to be capped, selecting the suitable film from those present in the magazine 12. For example, a suitable known sensor can also be provided. that detects the format of the package and commands the machine to prepare for that format.

Furthermore, the change of a reel in the magazine (for example because it is exhausted or because it is necessary to use a new type of film not in the magazine) is facilitated by the fact that the plurality of reels in the magazine can be kept at a relatively low and comfortable height for the extraction and re-insertion of reels, reducing fatigue and risks for an operator who has to perform the change and also making the operation faster. The mobile (and in particular rotating) carousel also allows the reel to be moved to a convenient position for extraction and re-insertion. For example, in the case of a rotating carousel as shown by way of example in the drawings attached hereto, the position for the change can be that of the top left reel in figure 1.

Naturally, the above description of embodiments applying the innovative principles of the present invention is given by way of example of these innovative principles and must therefore not be taken as a limitation of the patent scope claimed herein.

For example, the magazine can also be dimensioned for a greater number of reels than that shown, by increasing the dimensions and / or varying the shape of the carousel, as can now be easily imagined by the technician.

The transfer device can also be made with a movement kinematics different from that shown. For example, instead of a parallelogram kinematics, a carriage sliding on rails (advantageously but not necessarily horizontal) can be used to move between the first and second positions of the transfer device.

A machine according to the principles of the invention can of course be made suitable for treating films of any type used for packaging packs. For example, the film may or may not be heat-shrinkable, elastic, etc. Depending on the type of film, the machine may have suitable known devices for treating the particular film used (for example heat-shrinking frames or ovens, guiding and handling systems for the elastic film, winding systems, etc.) as easily imagined by the skilled technician. .

Furthermore, the machine may comprise other known mechanisms and systems for this type of machine, such as for example systems for lifting the pack towards the head above the hooding area, for example to allow the hood to be fitted up to under the base of the package.

The dimensions and proportions of the various parts of the machine may also vary according to specific practical needs. For example, the vertical section of the path will be made suitable for the maximum height of the packages that you want to treat, as well as the length of the horizontal section will depend on the corresponding maximum horizontal dimension of the packages you want to treat, etc.

Claims (12)

Claims 1. Hooding machine (10) comprising an area (19) for receiving a package (18) to be hooded and a hooding head (17) to which a strip of film (42), intended to form a hood (60) to be hooded fit on the pack, it is fed starting from an initial area (15) of a feeding path (14) towards the capping head (17), characterized in that it comprises: -a magazine (12) with a carousel (22) which supports a plurality of film reels (23) and which is movable to alternatively bring one of the film reels (23) into an operative position; -a delivery device (30) associated with each reel of film (23) and which receives a free end of the film of the associated reel (23), the carousel (22) comprising seats (31) for receiving each delivery device ( 30); - a transfer device (32) which can move between a first and a second position and is suitable: - in the first position to withdraw from one of said reception seats (31) a dispensing device (30) with the free end of the film of the associated reel (23) which is in the operating position; - in the second position to move said dispensing device (30) in correspondence with the initial area (15) of the feeding path (14) to feed the film of the reel (23) in said operative position to said path (14). Hooding machine (10) according to claim 1, characterized in that the film in reel is in the form of a film tube in a folded and flattened condition to be stretched transversely by the hooding head (17). Hooding machine (10) according to claim 1, characterized in that the carousel (22) is movable by rotation around its central horizontal axis (24) to alternatively bring one of the reels of the plurality into said operating position. 4. Hooding machine (10) according to claim 3, characterized by the fact that the reels (23) are arranged horizontally with parallel axes around the central horizontal axis (24) of the carousel (22). Hooding machine (10) according to claim 1, characterized in that the transfer device (32) has a head (35) which is vertically movable by means of an actuator (37) and which is adapted to accommodate the dispensing device ( 30) to be moved between said first and second position. 6. Hooding machine (10) according to claim 1, characterized in that the transfer device (32) is movable between first and second position by means of a parallelogram kinematic mechanism (36). Hooding machine (10) according to claim 1, characterized in that the seats (31) have couplings (45) for gripping and removably supporting the corresponding dispensing device (30) from its opposite lateral ends (46, 47). Hooding machine (10) according to claim 1, characterized in that each seat (31) has an associated pad (50) to block the film of the dispensing device (30) when it is in the seat (31). Hooding machine (10) according to claim 1, characterized in that it comprises a motor device (27) which engages the reel (23) in the operative position to rotate it on command. 10. Hooding machine (10) according to claim 2, characterized in that in the initial area (15) of the feeding path (14) there is a device (33) for transversal cutting of the film strip and possibly for transversal sealing downstream of the cut to form a tube segment forming a cap (60) to be fed to the capping head (17). 11. Hooding machine (10) according to claim 1, characterized in that each dispensing device (30) comprises a body (40) with a return roller (41) placed at an inlet end and on which the strip (42) reaches ) of film coming from the corresponding reel (23) to then pass into a guide passage (43) in the body (40) and exit from an upper end (44) of the body (40). Hooding machine (10) according to claim 2, characterized in that the dispensing device (30) is suitable for moving two facing faces (42a and 42b) of the free end of the film tube (42) away from each other in it, so that when the dispensing device is moved in correspondence with the initial area (15) of the feed path (14), these two faces can be gripped near their lateral edges by pincers (34) which are motorized to slide along the feed path (14).