This invention relates to a device for supporting reels of webs with self-adhesive labels, in particular intended to be used in labelling machines equipped with systems for joining the webs.

It is known that labelling machines (or the related labelling units) intended to apply self-adhesive labels are supplied with said labels applied one after another on suitable backing webs which are wound in reels.

Although there are many labels (several thousand) on each reel, the ever increasing productivity of labelling machines has increasingly highlighted the problem linked to the switch from one reel to another, since a reel can be used up within a few dozen minutes.

Where stopping the machine briefly to fit a new reel in the past did not cause particular problems, nowadays that would no longer be possible without drastically reducing productivity.

Consequently, various solutions have gradually been studied and put forward to allow joining of the end of one reel with the start of the next reel without having to stop the machine or which minimise the down time.

In particular, manual solutions were studied (in which joining is performed manually by the operator), as well as semi-automatic solutions and automatic solutions.

In all cases, the machine usually comprises two supports, one for the reel being unwound and one for the new reel, as well as systems for retaining the starting edge of the new reel which already has an adhesive element on it, in a standby position.

In all of the prior art solutions, when a first reel mounted on a support finishes, the starting part of the web of a second reel mounted on the other support is joined to the end part of the first web, then the first reel is substituted with a new one. Similarly, when the second reel finishes the starting part of the web of the reel used to substitute the first is joined to the end part of the second web, and so on.

However, the prior art solutions are all affected by the fact that the webs to be joined are asymmetrical, since the labels are applied on only one side of the web. Consequently, depending on how the two reels of the webs to be joined are positioned and how the reels are positioned, the joining operation may require various even relatively complex operations. In general, it may be the case that the new web to be joined to the web that is about to finish is positioned at the side of the latter on which the labels are located or at the opposite side on which no labels are present.

Consequently, in the prior art apparatuses, if joining of the web of the above-mentioned second reel to that of the first reel can be performed using some methods, joining of the web of the new reel that substituted the first, now finished one, to the web of the second reel that is about to finish must be performed using different methods.

DE 198 18 384 A1 discloses an appliance method for joining strips of adhesive labels. A driven feeder holds the start of the new support strip. The start of the new support strip is held in a stationary position, accelerated to the feeder speed of the old support strip and conveyed between pressure surfaces.

DE 100 63 000 A1 discloses a roll changing system for web-fed printing machine, comprising rotating shafts on which old and new rolls are mounted and can slide in diagonal guides which cross each other, allowing their position to be adjusted.

US 2,000,809 discloses a roll handling mechanism.

In this context, the technical purpose which forms the basis of this invention is to provide a device for supporting reels of webs with self-adhesive labels that overcomes the above-mentioned disadvantages

In particular, the technical purpose of this invention is to provide a device for supporting reels of webs with self-adhesive labels that allows the webs to be joined to always be made available to the labelling machine with the same mutual positioning, in such a way that the join can always be made in the same way.

The technical purpose specified and the aims indicated are substantially achieved by a device for supporting reels of webs with self-adhesive labels as described in the appended claims.

Further features and the advantages of this invention are more apparent in the detailed description, with reference to the accompanying drawings which illustrate several preferred, non-limiting embodiments of a device for supporting reels of webs with self-adhesive labels, in which:

• Figure 1 is an axonometric view of a labelling unit of a labelling machine, equipped with a supporting device in accordance with this invention;
• Figure 2 is an enlarged view of only a joining device and the supporting device of Figure 1;
• Figure 3 is an axonometric view, also showing the reels of web, of the supporting device of Figure 2;
• Figure 4 shows the device of Figure 3 without the reels and the related supports;
• Figures 5 and 6 are respectively an axonometric and a front view of a part of a positioning unit of a reel support of the supporting device of Figure 3;
• Figures 7, 9, 11, 13, 15, 17 and 19 show perpendicularly to a guide of the device, operation of the device of Figure 3 concerning the movement of a support on it;
• Figures 8, 10, 12, 14, 16, 18 and 20 are respectively enlarged views of VIII, X, XII, XIV, XVI, XVIII, XX of Figures 7, 9, 11, 13, 15, 17 and 19;
• Figures 21 to 24 are side views as in Figure 4, of the steps relating to removal of a support from the supporting device of Figure 3;
• Figure 25 shows the supporting device according to this invention with one reel unwinding and one reel standing by;
• Figure 26 shows, with the upper reel transparent, the device of Figure 25 at the moment when the lower reel finishes and unwinding of the upper reel is about to begin; and
• Figures 27 to 29 show the method for inversion of the position of the two supports of the device of Figure 26, with the reels shown transparent.

With reference to the above-mentioned figures the numeral 1 denotes in its entirety a device for supporting reels of webs with self-adhesive labels, made according to this invention. Hereinafter, it will be referred to simply as the device 1.

It should also be noticed that, hereinafter, when reference is made to a line of extension of three-dimensional objects, it will always refer to their main line of extension, that is to say, the one parallel to which the objects have their maximum length.

Figure 1 shows the device 1 connected to a labelling unit 2 of a labelling machine. Obviously, this invention relates to the device 1 in itself, to a labelling unit 2 equipped with the device 1 and to the entire labelling machine equipped with the device 1. However, since the labelling unit 2 visible in the figures is in itself of the known type, it will not be described in further detail herein.

Figure 2 also shows a joining unit 3 associated with the labelling unit 3 which allows the join to be made between two webs arriving from the supporting device. The joining unit 3 may be made in any way. However, being a unit that is in itself known, it will not be described in detail herein.

According to this invention the device 1 always comprises a supporting structure 5, at least two supports 6, each for supporting a reel of web with self-adhesive labels fixed on a first side 7 of it.

The supports 6 are rotatably mounted or mountable on the supporting structure 5, one at a first position (the lower position in the accompanying figures) and one at a second position (the upper position in the accompanying figures).

At least when the device 1 is associated with the labelling unit there are first guide means 8 and second guide means 9 present.

The first guide means 8 define a main feed path for a first web 10 which, in use, extends from a first reel 11 mounted on the support positioned in the first position, to an outfeed section 12 of the joining unit.

The second guide means 9 define a secondary feed path for a second web 13 which, in use, extends from a second reel 14 mounted on the support positioned in the second position, to an operating zone identified along the main feed path in the joining unit 3. Each support 6 is equipped with two idle return rollers 63 which, depending on the position adopted by the support, may be part of the first guide means 8 or of the second guide means 9.

It should be noticed that in the accompanying figures the main feed path and the secondary feed path coincide respectively with the way in which the first web 10 and the second web 13 extend.

Advantageously, along the respective paths, both the first web 10 and the second web 13 are positioned in such a way that their surface, although having a complex shape, is parallel to a reference axis transversal to the main feed path, which in the accompanying figures is horizontal and coincides with the axis of rotation of the reels 11, 14, and with their own sides positioned in the same way. In this way, if seen parallel to the reference axis, the main and secondary feed paths and the first web 10 and the second web 13 substantially appear to be a curved line.

According to the inventive aspect of this invention, on one hand the positions of the two supports 6 on the supporting structure 5 can be inverted, and, on the other hand, a support 6 positioned in the second position can be moved to the first position, allowing, during the entire movement, unwinding of the second web 13 from the second reel 14 and, in use, its free feeding from the second reel 14 towards the operating zone. In this way, when the movement is complete, it is possible to position a new reel on the other support 6 placed in the second position and so be in the starting situation. Consequently, thanks to this invention, in theory it would be possible to keep fitting new reels, joining them to the previous reels, without interruptions.

For that purpose, in the case of the device 1 illustrated in the accompanying figures, the supporting structure 5 comprises a guide 46, advantageously straight, on which the supports 6 are slidably mounted. Therefore, each support 6 can pass from the second position to the first position by sliding along the guide 46.

For the opposite passage of the other support 6, that is to say, from the first position to the second position, the guide 46 advantageously comprises two separate portions, a first portion 47 which defines the first position for the supports 6 and a second portion 48 which defines the second position for the supports 6. At least the first portion 47 is rotatable between an aligned position (Figures 4, 21 and 28) in which it is aligned with the second portion 48 and allows the passage of a support 6 from the second portion 48 to the first portion 47, and a rotated position (Figures 22 and 27) in which it is not aligned with the first portion 47 and allows the removal of a support 6 from it, preferably by simply pulling it off. Advantageously, the first portion 47 pivots at the supporting structure 5 according to an axis of rotation coinciding with that of the first reel 11 positioned on the support 6 in the first position. The second portion 48 in turn, on the opposite side to the first portion 47, is open for allowing one of the supports 6 to be coupled to it (Figure 29).

In the embodiment illustrated, the movement of the first portion 47 may be performed using a manually operated lever 49 connected to an air spring 50. However, in other embodiments it may be performed automatically and/or be motor-driven.

In the preferred embodiment, on one hand the guide 46 is constituted of a rail on which the supports 6 are slidably coupled by means of four V-shaped pulleys 51 which are positioned on both sides of the rail, and on the other hand it comprises at least one vertical component of extension (in the accompanying drawings it is in fact set at an angle of approximately 60° to the horizontal plane).

To facilitate the movement of the supports 6 and holding in the second position, the device 1 advantageously comprises at least one positioning unit 52, movable parallel to the guide 46 between an upper position in which it retains a support 6 positioned in the second position, a lower operating position in which it can support a support 6 positioned substantially in the first position, and a lower non-operating position in which it is positioned lower than the lower operating position and is uncoupled from the support 6 in the first position.

In the preferred embodiment, the positioning unit 52 comprises a body 53 (Figures 5 and 6) comprising a resting portion 54 and a following portion 55. The resting portion 54 (constituted of a cantilever-style pin in the accompanying figures) is designed to interact with a support 6 so as to sustain it.

In contrast, the following portion 55 is slidably associated with a cam portion 56 of the supporting structure 5. Advantageously, the following portion 55 comprises two following rollers 57 which are at a distance from one another and from an axis of rotation of the body 53.

In fact, the body 53 is rotatable about an axis of rotation which translates with the body 53 and which is transversal to a main line of extension of the guide 46. In particular, the body 53 is rotatable between a sustaining position in which the resting portion 54 can interact with a support 6 mounted on the guide 46 so as to sustain it (Figure 8), and a home position in which the resting portion 54 cannot engage with a support 6 associated with the guide 46 (Figure 16). There are also elastic means 58 (a torsion spring in the accompanying figures) associated with the body 53 for pushing it towards the home position. In contrast, the cam portion 56 in turn causes forced positioning of the body 53 in the sustaining position at least at the positioning unit 52 upper position, whilst it allows it to rotate towards the home position at least near to and at the lower operating position and between the lower operating position and the lower non-operating position. In fact, in this way it is possible to perform the translation of the positioning unit 52 from the non-operating home position to the sustaining position even when a support 6 is present in the respective first position.

In the accompanying figures the movement of the body 53 along the cam portion 56 is achieved by means of a cylinder without a rod 59, equipped with a slide 60 to which the body 53 is rotatably connected.

The sequence of steps for the passage of a support 6 from the second position to the first position (once the latter is free) and for preparing the device 1 to receive another support 6 in the second position is illustrated in Figures 7 to 20.

Initially (Figures 7, 8), the body 53 is in the upper position and, thanks to the interaction of the cam portion 56 with the following portion 55, in the sustaining position, with the resting portion 54 interacting with a corresponding resting element 61 fixed to the support 6, sustaining it. During the entire descent of the body 53 to the lower operating position, the weight of the support 6 overcomes the resistance of the elastic means 58 and holds the body 53 rotated with the following portion 55 only partly coupled to the cam portion 56. Relative to a lower following roller 57 of the following portion 55, the resting portion 54 is in fact positioned on the other side of a vertical plane passing through the pivoting point of the body 53. When the body 53 reaches the lower operating position, the support 6 reaches the end of its stroke corresponding to the first position, and it engages in a suitable fork 62 fixed to the guide 46 (Figure 11), and advantageously fixed to the first portion 47 for rotating with it (Figure 22).

At that point, the further descent of the body 53 frees the resting portion 54 and the elastic means 58 can return the body 53 to the home position. At this point, the resting portion 54 is not aligned with the resting element 61 fixed to the support 6 which is in the first position (Figures 13, 14).

Therefore it is possible to return the positioning unit 52 towards the upper position without there being any interaction between the resting portion 54 and the resting element 61 of the support 6 in the first position (Figures 15, 16).

When the body 53 reaches the upper part of the cam portion 56 (Figures 17, 18) the interaction between the latter and an upper following roller 57 of the following portion 55 causes a new rotation of the body 53 towards the sustaining position, so that when the body 53 reaches the upper position it is ready to receive and support a new support 6 (Figures 19, 20).

Regarding overall operation of the device 1 according to this invention, that is to say, the feeding of the webs 10, 13 to the joining unit 3, the figure shows the situation running regularly, with the first web 10 being unwound, and the second web 13 ready for the join to be made in the joining unit (therefore, stationary for the time being).

When the first web 10 finishes (Figure 26), the joining unit is activated and makes the join between a final end of the first web 10 and a starting end of the second web 13. Then unwinding of the second web 13 begins and it is fed to the labelling machine (Figure 27).

At this point, it is possible to start the operations for inverting the positions of the two supports while unwinding of the second web 13 continues.

For that purpose, first the first portion 47 of the guide 46 is rotated into the not aligned position (Figure 22) and the empty support 6 in the first position is removed (Figures 23 and 27). When the first portion 47 has been returned to the aligned position (Figure 24) it is possible to slide the other support 6 from the second position to the first position (Figure 28).

At that point, the other support 6 previously removed, loaded with a new reel, can be fitted on the second portion 48 of the guide 46 (Figure 29) until it rests on the body 53 in the sustaining position, restoring the condition of Figure 25.

This invention brings important advantages.

In fact, thanks to the device according to this invention it has been possible to provide a device for supporting reels of webs with self-adhesive labels, that always allows two webs to be joined to each other to be made available to the labelling machine with the same mutual positioning, in such a way that the join can always be made in the same way, thereby also making the structure of the joining unit that will be used simpler.

Finally, it should be noticed that even the cost linked to implementing this invention is not very high compared with similar prior art devices.

The invention described above may be modified and adapted in several ways without thereby departing from the scope of the inventive concept.

All details of the invention may be substituted with other technically equivalent elements and the materials used, as well as the shapes and dimensions of the various components, may vary according to requirements.