FR3108594A1 - Device for supplying film to a shrinkwrapper, with at least two unwinders each provided with a cover casing - Google Patents

Abstract

Title: Device for supplying film to a shrinkwrapper, with at least two reels each provided with a covering casing The invention relates to a device (1) for supplying film (F) to a shrinkwrapper (2), comprising at least two reels (10) each intended to accommodate a reel (B) of film, the reels (10) being side by side and arranged so as to accommodate the reels (B) of film parallel to each other, each reel (10) comprising a frame (11) carrying drive means (12) in rotation about an axis A of a reel (B) of film, characterized in that each reel (10) comprises a cover casing (100) delimiting an internal volume (V) capable of covering the drive means (12) and a reel (B) of film present on the reel (10), the casing (100) being mounted so as to be able to move in translation on the frame according to the axis A between a position covering the reel (B) of film and a free position providing access to the b reel (B) of film. Figure for abstract: Fig. 5

Description

Device for supplying film to a shrinkwrapper, with at least two reels each provided with a covering casing

The field of the invention is that of the design and manufacture of plastic film packaging machines.

More specifically, the invention relates to the design of shrink wrappers and associated equipment.

Remember that the function of a shrink wrapper is to wrap products in plastic film, heat-shrinkable or not. The shrinkwrapper is generally the first element of a packaging line under plastic film and preferably under polyethylene film.

The operating principle of a shrinkwrapper is as follows: an upper plastic film is welded with a lower film to form a substantially vertical film curtain. The product to be packaged is transported by a conveyor in the direction of the previously formed curtain. The conveying of the product causes the product to push against the curtain, then generates an unwinding of the upper and lower films from their respective reels. Photoelectric cells (or any other means) make it possible to detect the rear end of the product to be packaged, the conveying then being stopped. At this stage, a welding device automatically closes on the upper and lower films, behind the product. In general, a double weld and a cut are made, thus completing the wrapping of the product.

At the same time, the film curtain is replenished for the next product.

Of course, each shrinkwrapper is designed and manufactured according to the dimensions and characteristics of the products to be packaged.

According to a classic design of shrinkwrappers, the upper plastic film is unwound from a horizontal reel arranged above the conveyor and transversely to it, while the lower plastic film is unwound from a horizontal reel arranged in below the conveyor, and also transversely to it.

According to another more recent design, the reels are arranged on reels on the ground, positioned alongside the conveyor. In this case, the shrinkwrapper then includes a plastic film angle transmission device to bring the films into a configuration allowing the formation of the curtain mentioned above.

These reels next to the conveyor are generally implemented to save space in height and/or ensure film continuity, by implementing an active reel and reserve reel system. More generally, floor reels are chosen for ergonomic and safety purposes, in that they allow operator intervention on the ground when changing the reel, and not at height.

Moreover, in this second type of shrinkwrapper, the reels are generally implemented in pairs.

Indeed, whether for the lower film or the upper film, two reels, each intended to accommodate a reel of film, are arranged next to each other so as to accommodate the reels of film parallel to each other. Thus, a first reel is used to supply the film to the shrinkwrapper and, when the reel in question is close to being completely unwound, the second reel is manipulated in such a way as to bring the film from the second reel into contact with the film from the first reel with a view to connecting (for example by welding, or by double-sided gluing) the two films together. A cutter bar then cuts the film from the first reel to separate it from the film from the second reel (the cut can alternatively be performed manually). The film from the second reel then becomes the one that feeds the shrinkwrapper.

Of course, this operation is carried out while the shrinkwrapper and the reels are stopped.

However, as soon as the two films are welded and separated from each other, the film supply to the wrapper is resumed as soon as possible, to limit the downtime of the wrapper.

An operator then proceeds to replace the completely unwound reel with a new reel, which will be put on hold, the corresponding reel being stopped, until the reel of the neighboring reel is completely unwound. The operation of welding the films of the two reels, as described above, is then repeated.

However, when replacing a completely unwound reel with a new reel, the neighboring reel is in action (to limit the downtime of the shrinkwrapper as mentioned above). In other words, the drive means associated with the reel rotate the reel of plastic film which feeds the shrinkwrapper.

It should be noted that, to facilitate the connection by connection of the films of the two neighboring reels, these are arranged relatively close to each other. As a result, when the operator replaces a reel on one of the reels, he operates in the immediate vicinity of the other reel which is in action.

The phase of replacing a reel on one of the two reels while the other is in action is therefore not an operation without risk for the operator.

Indeed, the rotational drive of the reel that feeds the shrinkwrapper has a re-entrant angle on each side of the reel, which constitutes a risk. In other words, it is possible that, inadvertently, a part of the operator's body, or a piece of clothing he is wearing, is brought into contact with the means for driving the coil and/or the coil itself. Such a situation can lead to a phenomenon of swallowing of the part of the body and/or of the garment between the reel and the corresponding rotary drive means, with more or less significant consequences if the operator does not manage to release quickly or if the rotating drive means are not stopped quickly.

Of course, such an eventuality is unacceptable.

The object of the invention is therefore to overcome this drawback of the prior art.

More specifically, the object of the invention is to propose a device for supplying film to a shrinkwrapper comprising two reels side by side which eliminates, or at the very least considerably limits, the risk of a re-entrant angle when replacing a reel by an operator.

The invention also aims to provide such a device for supplying film to a shrinkwrapper which entails a reduced number of additional operations to be carried out to ensure the safety of the operator.

The invention also aims to provide such a device for supplying film to a shrinkwrapper which is simple in design, easy and quick to implement.

Another object of the invention is to provide such a device for supplying film to a shrinkwrapper which can easily be attached to an existing shrinkwrapper which does not have one.
These objectives, as well as others which will appear subsequently, are achieved thanks to the invention which relates to a device for supplying film to a shrinkwrapper, comprising at least two reels each intended to accommodate a reel of film, the reels being side by side and arranged so as to receive the reels of film parallel to each other, each reel comprising a frame carrying means for driving in rotation about an axis A of a reel of film, characterized in that that each reel comprises a covering casing delimiting an internal volume capable of covering the drive means and a reel of film present on the reel, the casing being mounted so as to be able to move in translation on the frame along the axis A between a covering position from the film reel and an unobstructed position providing access to the film reel.

Thus, thanks to the invention, the operator who replaces a reel on a reel while the neighboring reel is in operation, is protected from any risk of a nip point with respect to the reel in operation.

Indeed, while the operator proceeds to replace the reel, the reel in the immediate vicinity, in operation, is secured by the casing of said reel which covers both the drive means and the reel, both in rotation, with respect to to the wire feeder in operation. As a result, the operator can only be in contact with the casing of the reel in operation, this casing being, during this phase, fixed, and therefore presenting no risk to the operator.

With regard to the reel which accommodates the reel of film to be replaced, the operator simply has to translate the casing of said reel to bring it into an open position so as to completely uncover the reel of film to be replaced.

Of course, as is conventionally the case, the reel which presents the reel of film to be replaced is stopped prior to the replacement of the reel and throughout the replacement of the reel.

It is noted that the translational mobility of each casing on the frame of the corresponding reel is an advantageous solution compared to other possible movements of the casing, such as for example the implementation of a pivoting cover and in particular of a cover pivoting around a longitudinal hinge which would provide, in the open position, a particularly significant obstacle to access to the coil to be replaced. In addition, due to its relatively large dimensions, a pivoting hood would generate design constraints and/or a risk of falling due to its weight.

According to an advantageous solution, the casing extends between a first end and a second end, the first end having a transverse wall preventing access to the internal volume, the first end forming the front of the casing when the casing moves from the covering position to the released position.

In this way, the casing thus formed provides protection for the operator at the level of the first end of the casing, preventing any contact of the operator with the moving, and in particular rotating, elements present inside the internal volume of the crankcase.

In this case, according to an advantageous solution, the first end has a gripping means.

Thus, it is easy for the operator to grasp the gripping means to tow (the first end constituting the front of the casing when moving the casing from the covering position to the released position) the casing to its position unobstructed to provide access to the film reel. This gripping means can of course also be used to push the casing from its disengaged position to its position for turning the film reel.

Advantageously, the first end has ground connection means.

In this way, we avoid having to design the casing and its connection to the chassis with a possible large overhang. On the contrary, the presence of the means of connection to the ground avoids any cantilever and, moreover, ensures the stability of the casing in all or almost all positions.

In this case, the ground connection means preferably comprise ground rolling means.

Thus, the translational movement of the casing, whether from its disengaged position to its covering position, or vice versa, can take place without effort on the part of the operator, or with a minimum of effort, as regards to pull or push the casing by rolling it on the ground via the rolling means on the ground.

According to a particular embodiment, the second end of the casing is open, the frame having a transverse fixed wall against which the casing bears in the covering position.

This transverse fixed wall completes the protection of the operator moving near the reel, avoiding any contact with the moving parts and in particular in rotation inside the internal volume of the casing.

According to a preferred embodiment, the supply device comprises, for each reel, a position sensor intended to detect the covering position of the casing, and control means connected to the position sensor, the control means authorizing a drive of the drive means in the covering position of the casing.

The protection of the operator vis-à-vis the reel when the casing uncovers, at least partially, the reel and the drive means present on the corresponding reels, is thus made automatic.

Indeed, the combination of the position sensor and the means for controlling the drive means makes it possible to motorize the drive of the drive means only if the casing is in the covering position. In other words, conversely, the control means prohibit the driving of the drive means when the casing is in the disengaged position, insofar as, in this position, it could give access to parts of the moving machine.

According to a preferred solution, the supply device comprises a device for connecting the films of the two side-by-side reels to one another, such a connecting device being advantageously associated with a thread cutting device.

Without departing from the scope of the invention, it is noted that the cut can be performed manually.

Other characteristics and advantages of the invention will appear more clearly on reading the following description of a preferred embodiment of the invention, given by way of a simple illustrative and non-limiting example, and the appended drawings, among which:
- Figure 1 shows schematically and in perspective a shrink wrapper associated with a film supply device according to the invention;
- Figure 2 illustrates schematically, seen from the end, a film supply device according to the invention;
- Figure 3 is a schematic top view of a film supply device according to the invention;
- Figure 4 is a schematic top view of a film supply device according to the invention, with the housing of one of the reels in the disengaged position;
- Figure 5 is a schematic perspective view of a film supply device according to the invention, with the housing of one of the reels in the disengaged position;
- Figures 6 and 7 are schematic views of the devices for connecting the films together and for cutting, according to two successive working steps.

As illustrated by FIG. 1, the invention applies to a device 1 for supplying film intended to supply a wrapping machine 2 of the type described above.

According to the present embodiment, the film supply device comprises a first pair 1A of reels intended to supply, via a bevel gear system, an upper film to the shrinkwrapper. The supply device 1 further comprises a second pair 1B of reel intended to supply, also via an angle transmission system, a lower film to the shrinkwrapper 2.

According to a principle known per se, each pair 1A, 1B comprises two reels 10, as illustrated by FIGS. 2 to 5, each intended to accommodate a reel B of film, the two reels of a pair being side-by-side. side and arranged to accommodate reels of film parallel to each other, each of the reels being able to be driven in rotation about an axis A by drive means 12.

Still in a manner known per se, these drive means 12 consist of a pair of rollers 120 parallel to each other, each having an axis of rotation parallel to the axis A. Thus, a reel B of film is arranged in contact and between the rollers 120, such that the rotational drive of the rollers 120 in the same direction of rotation drives the reel B of film in a direction of rotation opposite to that of the rollers 120.

Of course, controlled motor means are associated with the rollers 120 of the drive means to cause the film reel B to be driven or, on the contrary, to stop the running of the film from the reel.

According to the principle of the invention, each reel 10 comprises a covering casing 100 delimiting an internal volume V capable of covering both the drive means 12 and the reel B of film present on the reel.

In addition, the casing 100 of each reel is mounted so as to be able to move in translation on the frame 11 of the reel, the casing 100 being able to be moved in translation along the axis A between a position covering the reel B of film, as illustrated by FIG. 3 which shows a configuration in which the casing 100 of each reel is in the covering position, and a disengaged position providing access to the reel B of film, as illustrated by FIG. 4 which shows the casing 100 d one of the reels in the released position, in this case the reel in the high position in Figure 4.

The translational guidance of the casing 100 on the frame 11 of the corresponding reel can be ensured by any appropriate means known to those skilled in the art, and in particular:
- Lateral and longitudinal grooves presented by the frame, in which the lower edges of the casing slide;
- running gear (rollers, ball or conical running gear, sliding strips, etc.), motorized or not;
- …

It is noted that the drive of the casing in translation can be manual or motorized. For the purposes of simplification and reduction of manufacturing costs, the drive of the casings is manual according to the present embodiment.

In addition, as shown in Figures 2 to 5, each casing comprises:
- Two longitudinal side walls 1001, preferably transparent, the ends or lower edges of which are mounted movable in translation along the axis A on the frame 11;
- a horizontal upper wall 1002, and connecting the upper end of the longitudinal side walls 1001.

Of course, the height of the longitudinal side walls 1001 is dimensioned so that the casing 100 comes to cover, with a more or less adjusted functional clearance, a “full” coil B whose diameter is known.

As shown in Figure 3, the housing 100 extends along the longitudinal axis A, between a first end 101 and a second end 102 delimiting between them the length of the housing 100. Again, this length separating the two ends of the casing is sized so that the casing is capable of receiving and covering the entire length of a reel B of film whose length is known.

The first end 101 forms, in the configuration illustrated in FIG. 3, the front wall of the casing when the casing moves from the covering position to the disengaged position. This first end 101 is provided with a transverse wall 103 (FIG. 5), preventing access to the internal volume V delimited by the casing.

The transverse wall 103, to prevent access to the internal volume delimited by the casing, extends over the entire surface extending between the longitudinal side walls 1001 and the upper wall 1002 of the casing.

According to the embodiment illustrated by FIGS. 2 to 5, the first end 101 of the casing also has the following characteristics:
- A gripping means 104 is present at the first end of the casing, in this case taking the form of a mechanically welded, or screwed, or even bolted metal handle on the transverse wall 103 of the casing;
- ground connection means 105 (Figure 5) are present at the first end 101 of the housing and take, according to the present embodiment, the form of two side legs, for example in the extension of the longitudinal side walls 1001 of the housing .

In addition, the legs constituting the ground connection means 105 have ground rolling means 106 at their lower end. These rolling means take the form of unidirectional wheels, oriented so as to roll in a direction parallel to the axis AT.

Furthermore, the second end 102 of the casing is open, the frame 11 having a transverse wall 110 against which the casing bears when it is in the covering position. This transverse wall 110 can be pivotally mounted, between a position prohibiting access to the internal volume of the casing, and a position giving access to the internal volume of the casing. Thus, by opening the pivoting wall, it is possible for the operator to take out or insert a reel longitudinally.

According to another feature of this embodiment, each reel 10 incorporates a position sensor 13, for example in the form of a feeler. This sensor is positioned so that a stop 130 carried by the casing 100 comes to press on the position sensor 13 when the casing is brought into the covering position.

In addition, control means 14, mounted in a general control electrical cabinet, are connected to the position sensor 13 so as to:
- Authorize the driving of the drive means 12 when the casing is in the covering position;
- stop the drive of the drive means 12 when the casing leaves the covering position of the casing, which results in the fact that the stop 130 no longer comes to rest on the position sensor 13.

Furthermore, as shown in Figures 6 and 7, a support plate 15 is mounted between the reels of the same pair, this plate having in particular the function of:
- temporarily rest a reel before tilting it to one side or the other on one of the reels; - to access the device for connecting the films between and manually proceed to the connection of the films, this by rotating the support plate around a hinge (not shown).

As illustrated, this support plate 15 has a receiving surface 150 in V, ensuring the lateral stability of a coil resting on the support plate.

According to yet another feature of this embodiment, a connection device 16 is provided to allow the connection between the films of the reels B of the side-by-side reels, this connection device being associated with a cutting device 17 of film .

The connection device can for example be a welding device, comprising a movable member for pressing one end of the film from the new reel (on the left in FIGS. 6 and 7) with the end of the film from the unwound reel (on the right on Figures 6 and 7), this movable member from heating and welding the films against each other. It should be noted that other systems for connecting the films to one another can be implemented.

Then, the cutting device is actuated (in this case pivoted) in the direction of the film from the unwound reel to cut it and separate it from the connection made (figure 7).

With a device for supplying film to a shrinkwrapper as described above, the operations consisting in swapping an unwound reel with a reserve reel can take place in the following way.

When supplying film to the shrinkwrapper, only one reel B among that of the two side-by-side reels is driven in rotation to feed the shrinkwrapper. During this operation, the two casings 100 of the two side-by-side reels are in the covering position.

When the reel B which supplies the shrinkwrapper reaches a stage where it is almost completely unwound (in this case the reel on the right in figure 2 which has a significantly reduced diameter compared to the reel of the reel on the left), the operator causes the drive of the drive means to stop.

This stop can be caused by the simple fact of removing the corresponding casing 100 from its covering position towards its removed position, which results in the absence of abutment of the abutment 130 against the position sensor 13. indeed, the control means connected to the position sensors 13 detect the absence of a signal coming from the position sensor and control the stopping of the drive means of the reel in question.

More specifically, the operator translates the housing of the reel integrating the new reel.

The operator can thus access the film from the new reel (on the left side in FIG. 2) and connect it to the film from the unwound reel (right side in FIG. 2), thanks to the welding device 14. Once the two welded films, the film of the unwound reel is cut to be separated from the weld made.

The casing of the reel with the new reel is brought back to the covering position.

The drive of the reel drive means on the new reel side can be re-engaged.

While the film from the new reel feeds the shrinkwrapper, the operator can replace the unwound reel. To do this, it brings the casing of the corresponding reel into the separated position, this in complete safety since the control means of the corresponding drive means prohibit the drive of the drive means of the reel in question. The operator replaces the unwound reel with a new reel, and replaces the casing 100 in the covering position.

It should however be noted that, for safety reasons, the film supply to the shrinkwrapper may only be authorized if the two casings of the two side-by-side reels are in the overlapping position. In other words, resumption of the film supply to the shrinkwrapper may only be authorized once all the replacement operations have been carried out and therefore the unwound reel is replaced by a new reel, with the corresponding casing replaced in the covering position.

Claims (9)

Device for supplying (1) film (F) to a shrinkwrapper (2), comprising at least two reels (10) each intended to receive a reel (B) of film, the reels (10) being side by side and arranged so as to receive the reels (B) of film parallel to one another, each reel (10) comprising a frame (11) carrying drive means (12) in rotation about an axis A of a reel (B ) of movie,
characterized in that each reel (10) comprises a covering casing (100) delimiting an internal volume (V) capable of covering the drive means (12) and a reel (B) of film present on the reel (10) , the housing (100) being mounted so as to be able to move in translation on the frame along the axis A between a position covering the reel (B) of film and a disengaged position providing access to the reel (B) of film. Device for supplying film to a shrinkwrapper according to claim 1, characterized in that the casing (100) extends between a first end (101) and a second end (102), the first end presenting a transverse wall (103) preventing access to the internal volume (V), the first end (101) forming the front of the casing (100) when the casing moves from the covering position to the disengaged position. Device for supplying film to a shrinkwrapper according to Claim 2, characterized in that the first end (101) has a gripping means (104). Device for supplying film to a shrinkwrapper according to Claim 2, characterized in that the first end (101) has means for connecting to the ground (105). Device for supplying film to a shrinkwrapper according to claim 4, characterized in that the ground connection means (105) comprise ground rolling means (106). Device for supplying film to a shrinkwrapper according to claim 2, characterized in that the second end (102) of the casing is open, the frame (11) having a transverse wall (110) against which the casing (100) comes to rest in recovery position. Device for supplying film to a shrinkwrapper according to any one of Claims 1 to 6, characterized in that it comprises, for each reel (10), a position sensor (13) intended to detect the covering position of the (100), and control means (14) connected to the position sensor, the control means allowing drive of the drive means (12) in the position covering the casing. Device for supplying film to a shrinkwrapper according to any one of Claims 1 to 7, characterized in that it comprises a device (16) for connecting the films of the two side-by-side reels to one another. Device for supplying film to a shrinkwrapper according to Claim 8, characterized in that the connecting device is associated with a film cutting device (17).