ES2595255T3 - Device for winding reels of web material - Google Patents

Abstract

An unwinding device (1) of reels (2, 3) of web material for feeding mainly a packing unit, located on the rear side of said device (1), which has a support structure (4) in the form of two consoles (7,8) and is provided with at least some means (5A) for receiving and rotating support of at least one first coil (2) in a first working position (6A) and of means (5C) for receiving at least one second coil in a waiting position (6C). Said device also has joining means (30) formed by a clamp (31) consisting of a first (32) and a second jaw (33) that extend parallel to the winding axes of the coils (2, 3 ), and transversely to a band (12) of the first coil (2); the first jaw (32) is located on the channeling path of the band (12) in the direction of a machine located at the top, and the second jaw (33) of mobile type and capable of occupying, thanks to the means of adapted drive (34), a position in application on the first jaw (32) and a waiting position (35) in which the band (12A) of the second coil (3), located in the waiting position (6C) on the unwinding device (1), it can be applied and kept on this second jaw (33). With all this, said device is characterized in that it contains: - At least some means (5B) for receiving and rotating support of said first coil (2) in at least a second working position (6B). - Means (14) for moving said first coil (2) from the first working position (6A) to the second working position (6B). - Evacuation means (15) of said first coil (2) from the second working position (6B) located on the support structure in question (4). - Transfer means (16) of said second coil (3) from the waiting position (6C) in the first working position (6A), which are formed by the rails of a guide system (17, 18) arranged between the consoles (7, 8), each of which extending along a horizontal part (25) and allowing the latter to join a mandrel (9) on which a coil (2, 3) is placed. In addition, said device (1) has articulated loading ramps (39) suitable to move from an unfolded position in which they serve as an extension to the horizontal parts (25), to a folded position in which said ramps (39) they disappear between the consoles (7, 8).

Description

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DESCRIPTION

Device for winding reels of web material

[0001] The present invention refers to a device for winding reels of web material for the feeding, principally, of a packing unit, which contains a support structure and is provided with means for the reception and support in rotation of at least one first coil in a first working position.

[0002] The present invention is encompassed within the field of devices for winding reels of web material.

[0003] The invention particularly concerns a bandwidth device.

[0004] It is known in the field of supply of web material the use of film-separating machines for feeding a packaging machine (usually of food products), formed by a film reel that begins to rotate by drive with the aim of taking the film to the packing machine.

[0005] The main problem in this type of machines is the replacement of the coil without interrupting production, which, on the one hand, seems very difficult to carry out with a simple machine or, on the other hand, it is possible but you have to resort to a complex and expensive machine such as those used in the field of printing.

[0006] In addition, the use of such complex machines for the packaging of products entails a significant cost since the packaging companies have a significant number of packing lines and, in the same packing line, there are several types of packaging They are used.

[0007] On the other hand, the same product could be conditioned depending on the type of packaging.

[0008] In fact, in the first place, the product in question is channeled into a first packing station to be arranged in a tray as a result of an embossing operation of a first uniform-shaped web material, which does not have a marking specific. Subsequently, the product in its tray is moved to a second packing station in which the tray is closed by heat sealing using a second band material that, unlike embossed material, presents a specific impression, such as a brand or a picture.

[0009] Depending on the final destination of the product (for example, depending on the distribution warehouse), the second heat-sealed material will change throughout the production. This change is even more frequent in the field of food.

[0010] It is difficult to imagine the construction of such complex winding machines. In addition, it is not conceivable to have to stop production every time to change the film.

[0011] Finally, the devices existing so far in the state of the art have important dimensions, which is problematic quite frequently due to the placement of said device along a packing line.

[0012] The most similar state of the art is represented in DE 90 16 526 U1.

[0013] It is within the framework of an imaginative approach that the creation of a simple, ergonomic and inexpensive machine that allows the operation of the film change without stopping production has been devised. In addition, thanks to the device according to the present invention, the connection between two film reels is facilitated.

[0014] The present invention aims to alleviate the drawbacks of the state of the art by proposing a reel device for reels of web material for the feeding, mainly, of a packaging unit located at the back of said device, which has with a support structure in the form of two consoles and is provided, at least, with means for receiving and rotating support of at least one first coil in a first working position and means for receiving, at less, a second coil in a waiting position. Said device also has joining means formed by a clamp that contains two jaws that extend parallel to the winding axes of the coils and transversely to a band; the first jaw is located in the path of the band in the direction of a machine located below and the second jaw is mobile and capable of occupying, thanks to the adapted drive means, an application position on the first jaw and a

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standby position in which the band of the second coil, located in the standby position on the vending device, can be applied and maintained on this second jaw.

[0015] Said device also has:

- At least some means for receiving and rotating support of said first coil in at least a second working position.

- Means for transferring said first coil from the first working position to the second position.

- Evacuation means of said first coil from the second working position located on said support structure.

- Transfer means of said second coil from the waiting position to the first working position.

- Said transfer means consist of rails in the form of a system of grains arranged between the consoles, each of which extended horizontally, which allow the union of a mandrel on which a coil is located; In addition, said device has articulated loading ramps capable of moving from a deployed position to disappear between the consoles.

[0016] According to another of the features of the present invention, the vending device has grinding means in view of the channeling of the web material in the direction of the use machine, characterized by the fact that it entails a joining table in the band travel path for joining the end of the band of the first coil in the second working position at the beginning of the band of the second coil in said waiting position or in the working position.

[0017] Other features and advantages of the present invention are set out in the detailed description below of the non-limiting embodiments in reference to the attached figures:

- Figure 1 shows a schematic and perspective representation of the dishealing device according to the present invention.

- Figure 2 shows a schematic and elevational representation of a stiffener device as described in Figure 1 in the frame of application to a packaging machine.

- Figures 3 to 10 show, in a schematic way, the steps of changing a reel of web material for the feeding of a packing machine such as the one shown by way of illustration in Figure 2.

[0018] As shown in the attached figures 1 and 2, the present invention refers to a device 1 of coils 2.3 of band materials, of synthetic, cellulose or other type, capable of intervening in the feeding of any transformation unit (for example, a packaging unit). As an example, within the framework of a possible application, the band material may be suitable to participate in an embossing operation for the definition of a continent that can be presented in the form of a film, transparent or not, and may lead to various impressions. and susceptible, for example, to be applied by heat sealing on the continents formed by embossing a band of adapted synthetic material.

[0019] Irrespective of which the delivery device 1 according to the present invention will contain a support structure 4 provided with means 5A for receiving and rotating support of at least a first coil 2 in a first workstation 6A .

[0020] Substantially, said support structure 4 can be presented in the form of two consoles 7, 8 capable of rotating a mandrel 9 on which one of the coils 2,3 is placed.

[0021] Said support structure 4 can also integrate various rewind rollers 10, 11 to channel a band of material 12 in the direction of the unit in which it is to be transformed. Especially, said unit may be formed by a heat sealer.

[0022] In particular, this support structure 4 can also house means for tensioning the band, such as a scale or diabolus system 13, in order to create a reserve stock and ensure the absorption of speed variations in the band 12 offset; This system 13 is particularly useful when the band 12 progresses discontinuously.

[0023] Thus, by way of example with regard to Figure 2, the system 13 (aqrn of scale) has at least one reenvfo roll 131, 132, 133 around which the band of the material 12 is partially wound, and that rewind roller or rollers 131, 132, 133 is positioned at the rotating ends on two support arms 134. Said support arms 134 are themselves pivotally mounted at one end 135 about a rotation axis. 136 transverse to said band 12.

[0024] In addition, said band 12, which is partially wound along the rewind roller or rollers 131

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132, 133, also does it partially and alternately around other rewind rollers 137 and 138 placed on the support structure 4, forming several strips of band 12 that create a reserve stock that allows to compensate for variations in speed in the movement of material band 12.

[0025] In Figure 2, the rotation shaft 136 appears located on the support structure 4 next to the packing unit, whereby the support arm 134 swings on the front of the unwinding device 1. However, it can be positively assessed to reverse said oscillation position of system 13; in other words, the axis of rotation 136 can be placed on the front of the unwinding device 1. An implantation of this type prevents, in case of oscillations of the support arms 134, hitting an operator who intervenes before said unwinding device 1.

[0026] It is also a considerable advantage that the system 13 of scale or diabolo facilitates a management of the size of the band stock and allows to detect, by specific technical means, the exceeding of a maximum stock that may result from an excess of time as for the sealing of two bands of material. Thus, the treatment unit of said band of material 12, located at the bottom of said system 13, can be stopped to allow the operator to finish the sealing. Said sealing stage will be described below.

[0027] As already indicated above, the stiffener device 1 according to the present invention has in its support structure 4 means 5A for receiving and rotating support of at least a first coil 2 in a first position of work 6A. To ensure a certain continuity of the feeding of the lower machine of the web material, either for the final winding of one coil 2, 3 for the replacement of another, or in the case of replacement, with said machine of the web material guarantees its feeding and for this it contains, according to the present invention:

- At least 5B means for receiving and rotating support of said first coil 2 in at least a second workstation 6B.

- Means 5C for receiving and supporting at least one second coil 3 in a waiting position 6C.

- Means 14 for moving said first coil 2 from the first working position 6A to the second position 6B.

- Evacuation means 15 of said first coil 2 from the second working position 6B located on said support structure 4.

- Transfer means 16 of said second coil 3 from the waiting position 6C to the first working position 6A.

[0028] Significantly, the means 5A, 5B, 5C for receiving and rotating support of a coil 2, 3, either in the first working position 6A, the second 6B or in the waiting position 6C, they are formed by support bearings in the consoles 7, 8, of the support structure 4. Subsequently a general description of said bearings will be made.

[0029] Advantageously, said first working position 6A of a coil 2,3 on the support structure 4 is located at a level higher than the second working position 6B. Also in a positive way, the waiting position 6C is positioned substantially at the same level as the first working position 6A but in a vertical plane displaced from the side opposite to the machine for treating the web material from said coils, so as to facilitate the transfer of the coil 2, 3 from the waiting position 6C to the first working position 6A.

[0030] It is clear that this waiting position 6C can also be arranged below or on the same axis as the working position 6A.

[0031] As for the means 14 for moving the first coil 2 from the first working position 6A to said second working position 6b as well as at least the transfer means 16 of the second coil 3 from the waiting position 6C in the first working position 6A, to say that they are mainly formed by a system of grains 17, 18 arranged in the consoles 7, 8 between said working positions 6A, 6B and the waiting position 6C; in the rails of said grating system 17, 18 it is possible that the ends of the mandrels 9 on which the first 2 and the second coil 3 are placed are maintained.

[0032] To take into account that said grating system 17, 18 can be defined by a set of adapted rails, a series of spaces arranged in the support consoles 7, 8.

[0033] In addition, since the second working position 6B is located at a lower level with respect to the first working position 6A, the translation means 14 are completed by means of retention and actuation 19 of the ends of the mandrel 9 along the rails of the tracks 17, 18 between the first working position 6A and the second position 6B.

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[0034] As they appear in figures 1 and 2, these positions are located in the same vertical plane, one under the other. The retention and actuation means 19 are thus advantageously constituted by ascending devices which allow the ends of the mandrel 9 to be retained and guided from said first working position 6A to the second 6B.

[0035] On the other hand, to the extent that the waiting position 6C is located substantially at the same level as the first working position 6A, the transfer means 16 can have, along the rails of the crane system 17, 18 , a simple stop 20 designed to temporarily hold a second coil 3 in said waiting position 6C before allowing it, by suppression, to achieve the first working position 6A.

[0036] As for the evacuation means 15, they are mainly formed by a system of grains 17, 18 that end on one side 21 or on the other 22 of the consoles 7, 8 of the support structure 4.

[0037] Preferably, said rails of the grating system 17, 18, are positioned, between the second working position 6B and the end 23 through which they flow, in a substantially horizontal way, they even have a slight downward slope that facilitates, precisely , the extraction of the coil. To take into account that these evacuation means 15 can, in turn, be completed with a stop 24 along the system of grains 17, 18 suitable for containing before the evacuation, by means of the ends of the mandrel 9, a coil 2, 3 in the second working position 6B.

[0038] In the same way, in the upper part of the waiting position 6C, the rails of the crane system 17, 18 can be extended by a horizontal part 25 which ends on one of the sides 21, 22 of the consoles 7, 8 of the support structure 4 allowing the union of a mandrel 9 on which a new coil is placed to be placed in said waiting position 6C, located on the unwinding device 1, by means of the union at said ends leading to the grid system 17, 18.

[0039] According to a preferable embodiment, the horizontal part 25 of each of the rails of the crane system 17, 18 that allows the union of a mandrel 9 on which a coil 2 or 3 is located, is extended by a articulated loading ramp 39 prepared to move from an unfolded position, in which said horizontal part 25 protrudes partly in front of the unwinding device 1, to a folded position where said ramp 39 disappears between the two consoles 7, 8 as can be seen in figure 2.

[0040] In this way, the operator deploys said ramps 39 when the mandrel 9 that carries the coil 2, 3 must be joined to the horizontal part 25. On the reverse that after loading, the operator folds said ramps 39 to allow a minimum obstruction around said device 1.

[0041] Such a configuration allows positively the withdrawal of the coil in case the operator has placed a coil by mistake on the loading ramps 39, before sealing the coil to the one in the winding phase.

[0042] Preferably, the horizontal portions 25 of the rails of the crane system 17, 18 and, in addition, their extension (the articulated change ramps 39), involve, at least on a part of said rails, zippers intended to cooperate with the sprockets located at the ends of the mandrel 9. This cooperation between the racks and the sprockets allows to ensure the perpendicularity of the axis of said mandrel 9 on which the coil 2 or 3 is mounted with respect to the rails of the crane system 17, 18.

[0043] In addition, the cooperation between the zippers and the gearwheels allows a demultiplication of the movement that prevents the coil 2, 3 from being rejected at high speed in the stripping device 1. In fact, a film-loaded coil can weigh up to one hundred kilos and, coupled at high speed without being braked, it may be capable of causing a degradation of the device 1 assembly. Thus, it is advantageously avoided that the coils 2, 3 are joined transversely in the loading ramps 39.

[0044] However, to allow free rotation of the coil 2 or 3 and its mandrel 9, firstly in the waiting position 6C and then in the working position 6A, it is imperative that, in these different positions, The cooperation between the rack and sprockets is uninterrupted. In this way, according to the present invention, at least immediately before said waiting position 6C, the zippers are interrupted along the horizontal part 25 of the rails of the crane system 17, 18, allowing precisely the free rotation of the ends of the mandrel on said rails 17, 18.

[0045] According to a preferable embodiment, said ends of the mandrel 9 are provided with rolling means, preferably in the form of rollers, allowing, on the one hand, the mandrel and, therefore, the coil, to wait for said waiting position 6C and , on the other hand, the rotation of the mandrel around its axis.

[0046] On the other hand, according to another particular feature of the present invention, at least one of the rails of the crane system 17, 18 is provided, slightly above said waiting position 6C, with a suitable folding stop

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to retain the corresponding end of the mandrel 9 of the coil in this waiting position 6C. Positively, said stop is designed to be foldable, preferably against the action of the elastic rejection means under the impulse of the end of the mandrel 9 in the direction of travel of the latter, in view of changing the coil. On the contrary, this stop is opposed to a reverse load shift.

[0047] However, in order to allow unloading, for example in the case of a loaded coil error, said stop acts in solidarity with the auxiliary retraction means, preferably in the form of a lever pivotally placed on the support structure 4, and that allows, by manual or motorized lifting, to deactivate said stop allowing precisely the withdrawal of the coil.

[0048] The following description refers to the process of placing and replacing a coil on the delivery device 1 according to the present invention.

[0049] In this way, in figure 3 the placement of a first coil 2 on the unwinding device 1 is illustrated. More specifically, the ends of the mandrel 9 on which the first coil 2 is placed appear joined, by means of the parts 25 on the rails of the grating system 17, 18, until said coil 2 is brought to the first working position 6a. Exactly in that first working position 6A, the ends of the mandrel 9 rest on the retention and actuation means 19 that each of the rails of the crane system 17, 18 entails.

[0050] As shown in Figure 4, the web material of said coil 2 then moves through the device until the machine located below is fed.

[0051] When this coil 2 comes to an end, more precisely, when its section 26 reaches a single distinguished diameter thanks to the adapted detection means 27 (of mechanical, optical or other type), the translation means 14 together with the retention and actuation means 19 lower said coil 2 to its second workstation 6B. This entails the displacement of said retention and actuation means 19 along the rails of the crane system 17, 18 involving the ends of the mandrel 9 on which said coil 2 is placed. In this second working position 6B, the stop 24 that completes the receiving and support means 5B retains the ends of the mandrel 9 in this second working position 6B and prevents the mandrel 9 from reaching the ends 23 of the rails of the grating system 17, 18. As can be done appreciate in figure 5, during the descent of the coil 2 from the first working position 6A to the second position 6B, the band 12 continues its winding by feeding the lower machine.

[0052] At the same time, the reception and support means 5C formed mainly by the stops 20 of the rails of the rail system 17, 18 which allow to retain a second coil 3 in a waiting position 6C are activated.

[0053] While this second coil 3 is placed by the union of the end of the mandrel 9 on which it is located in the horizontal parts 25 of the rails of the system of grains 17, 18, and whose end appears in cooperation with the stops 20 , the first coil 2 continues to unwind until the end of the band. Figures 7, 8 and 9 show the end of the band 28 of the first coil 2 next to the beginning of the band 29 of the second coil 3 thanks to the joining means 30 that will be described in more detail below.

[0054] As Figure 10 illustrates, once said union has been made, the second coil begins to be wound while the evacuation of the first coil intervenes through the ends 23 of the rails of the crane system 17, 18, after the disappearance of the stop 24 of the receiving and support means 5B. Obviously, this first evacuated coil and the retention and actuation means 19 on the rails of the crane system 17, 18 are traced so as to collect the ends of the mandrel 9 of the second coil 3 and keep it in the first working position 6A after removing the stops 20 corresponding to the receiving and support means 5C.

[0055] It should be noted that, instead of waiting for the total termination of the first coil 2 placed on the unwinding device 1, the band of said first coil 2 could be cut so as to allow the evacuation of the coil in question and its replacement by a new coil, which may be of a different material or appearance than the first band of the previous coil.

[0056] As regards the joining means 30, they are usually formed by a clamp 31 which has a first jaw 32 together with a second 33.

[0057] It is worth mentioning the advantage that said jaws 32, 33 extend parallel to the winding axes of the coils 2, 3 and transverse to a band 12, whose depression makes it possible to ensure the support of a suction band.

[0058] Preferably, the first jaw 32 will be located in the channeling path of the band 12

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in the direction of the machine located below while the second jaw 33 will be of mobile type and capable of occupying, thanks to the adapted drive means 34, an application position on the first jaw 32 and a waiting position 35 on the band 12A of the second coil 3 located in the waiting position 6C on the unwinding device 1, and may be applied on this second jaw 33 to be maintained and aspirated by the latter to finally reapply on the first jaw 32 below from which the band 12 of the first coil 2 passes.

[0059] It is also desirable, according to the present invention, that the unwinding device 1 is equipped with a safety device designed to prevent the mobility of the jaw 33, for example, when the packaging unit, such as the heat sealer, is in functioning. Such a device may be formed primarily by a stop that will retain the jaw 33 while the heat sealer is in operation; said stop will be retractable to allow its withdrawal when the operator wishes to apply said jaw 33 on the first jaw 32.

[0060] The fact that these joining systems 30 can be associated with cutting means 36 of the bands 12, 12A is also helpful. Said cutting systems 36 can also be associated with the fixed jaw 32 of the clamp 31 as well as with each of the jaws 32, 33.

[0061] In addition, it is considered very useful to associate said jaw or jaws 32, 33 of the clamp 31 corresponding to the joining means 30 with heating means for a heat sealing of the bands 12, 12A in synthetic material.

[0062] It can be thought that, more than a heat seal, it is a solution for the union of the bands. In this case, the joining means 30 may be equipped by gluing means.

[0063] According to another of the features of the present invention, the unwinding device 1 has braking means 37A, 37B, 37C associated, at least, with the first working position 6A and the second working position 6B on the structure of support 4, and even preferably also, to the waiting position 6C.

[0064] Said braking means 37A, 37B, 37C are designed to cooperate with complementary braking means 38 that the mandrel 9 has on which a coil 2, 3 is located. Thus, through said braking means 37a, 37B, 37C, it is possible to control the winding of a coil 2, 3, whatever the position that said coil occupies on the unwinding device 1.

[0065] According to an advantageous embodiment, the braking means 37A in the first working position 6A and the braking means 37B in the second position 6B are the same and are located on the retention and actuation means 19 corresponding to the translation means 14. Ultimately, only the braking means 37c in the waiting position are different from those involved in a coil when it is in its working position 6A and 6B.

[0066] A coil may not be loaded when the braking means 37A, 37B and 37C are open to avoid hitting said braking means.

[0067] In this way, the present device can, for example, entail means of detecting the load of the coil, being able to be mainly associated with the loading ramp 39, thus detecting the moment at which said ramp 39 is presented in An unfolded position.

[0068] These detection means can also be associated with the folding stop, making the order of folding of the stop by the mandrel 9 generate the brake opening thanks to an adapted sensor.

[0069] The advantages obtained from the present invention consist in that, on the one hand, the coils can be moved and evacuated from the unwinding device 1 from the same side 21 of the consoles 7, 8, assuming that on this side 21 the rails of the Grid system 17, 18 to access the waiting position 6C or to ensure evacuation from the second working position 6B.

[0070] The transfer of a coil from its first working position 6A to the second position 6B can be ensured automatically through a detection of the coil section thanks to the adapted means 27. In fact, said transfer can be signaled thanks to the appropriate visual and / or audible signaling means so that the operator rushes to raise a second coil to the racking device 1 and take it to the waiting position 6C.

[0071] Likewise, the visual and / or sound signaling means may be provided to signal to an operator the termination of the winding of a band from a coil in its second working position 6B to guarantee the union of a new band starting from a New coil

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[0072] As can be discerned from the previous description, the unwinding device, although leaving an easy replacement of a band or changing a coil, has a very simple conception so the cost is reduced. Furthermore, said device is particularly ergonomic and can, in fact, be easily disposed without requiring considerable space.

[0073] Accordingly, the present invention allows an effective response to the problem posed.

Claims (12)

5 10 fifteen twenty 25 30 35 40 Four. Five fifty 55 60 65 1. A baffling device (1) of reels (2, 3) of web material for feeding mainly a packing unit, located on the rear side of said device (1), which has a support structure (4) in the form of two consoles (7,8) and is provided with at least some means (5A) for receiving and rotating support of at least a first coil (2) in a first working position (6A ) and of means (5C) for the reception of at least a second coil in a waiting position (6C). Said device also has joining means (30) formed by a clamp (31) consisting of a first (32) and a second jaw (33) that extend parallel to the winding axes of the coils (2, 3 ), and transversely to a band (12) of the first coil (2); the first jaw (32) is located on the path of the band (12) in the direction of a machine located at the top, and the second jaw (33) of mobile type and capable of occupying, thanks to the means of adapted drive (34), an application position on the first jaw (32) and a waiting position (35) in which the band (12A) of the second coil (3), located in the waiting position (6C) on the unwinding device (1), it can be applied and kept on this second jaw (33). With all this, said device is characterized in that it contains: - At least some means (5B) for receiving and rotating support of said first coil (2) in at least a second working position (6B). - Means (14) for moving said first coil (2) from the first working position (6A) to the second working position (6B). - Evacuation means (15) of said first coil (2) from the second working position (6B) located on the support structure in question (4). - Transfer means (16) of said second coil (3) from the waiting position (6C) in the first working position (6A), which are formed by the rails of a grating system (17, 18) arranged between the consoles (7, 8), each of which extending along a horizontal part (25) and the latter allowing the union of a mandrel (9) on which a coil (2, 3) is placed. In addition, said device (1) has articulated loading ramps (39) suitable to move from an unfolded position in which they serve as an extension to the horizontal parts (25), to a folded position in which said ramps (39) they disappear between the consoles (7, 8). 2. An unwinding device (1) according to claim 1 characterized in that at least a section of the horizontal parts (25) of the rails of the crane system (17, 18) and at least a part of the ramps of load (39) that extend in said horizontal parts (25), are provided with zippers intended to cooperate with the sprockets located at each end of the mandrel (9); said cooperation will guarantee the perpendicularity of the mandrel axis (9) in relation to the rails of the crane system (17, 18). 3. An unwinding device (1) according to any one of claims 1 or 2, characterized in that the movable jaw (33) is equipped with a stopper that retains it when the packaging unit is put into operation. 4. An unwinding device (1) according to one of claims 1 to 3, containing grinding means in view of the channeling of the web material in the direction of the use machine, characterized in that it has a travel path of the band for the union of the end of the band (28) from the first coil (2) in said second working position (6B) at the beginning of the band (29) of the second coil (3) in the waiting position (5C) or in the working position (6A) in a joint table. 5. An unwinding device (1) according to one of claims 1 to 4, characterized in that the first working position (6A) of a coil (2, 3) on the support structure (4) is located at a level higher than the second work position (6B) with respect to the latter. 6. An unwinding device (1) according to any one of claims 1 to 4, characterized in that said waiting position (6C) is located slightly at the same level as the first working position (6A), but in a displaced vertical plane on the side opposite to the machine for treating the web material from said coils, so as to facilitate the transfer of the coil (2, 3) from the waiting position (6C) to the first working position (6A). 7. An unwinding device (1) according to any one of claims 1 to 6, characterized in that it has retention and actuation means (19) constituted by ascending devices that allow retaining and guiding the ends of the mandrel (9) from the first working position (6A) to the second position (6B).

 8.

 An unwinding device (1) according to any one of claims 1 to 7, characterized in that said press jaws (32, 33) allow to secure the support of a band (12) by aspiration.

 9. 5

 An unwinding device (1) according to any one of claims 1 to 8, characterized in that it has braking means (37A, 37B and 37C) associated, at least, with the first (6A) and the second working position (6B ) on the support structure (4), even preferably also at the waiting position (6C).

 10. 10

 An unwinding device (1) according to any one of claims 1 to 9, characterized in that it contains a scale system (13) having a stock of the material band (12), which has at least one roller Forwarding (131, 132, 133) around which or which said band is wound (12); said rollers (131, 132, 133) are installed at the rotating ends on two support arms (134). As for the arms (134), they are pivotally placed on one end (135) around a rotation axis (136) transverse to said band (12). Said system (13) shows

 fifteen

 also, at least, a rewind roller (137, 138) located on the support structure (4).

 eleven.

 A spreader device (1) according to claim 10, characterized in that the rotation axis (136) of the scale system (13) is located on the front of the spreader device (1), opposite the rear side at the level of which it is located The packing unit.

 20 12.

 An unwinding device (1) according to claim 10, characterized in that the weighing system (13) is associated with the means of detecting a maximum stock of material band (12) and allows the stopping of the packing unit in case of detection of an exceeding of a limit stock.