WO2025257863A1 - Apparatus and method for joining a strip having an adhesive face onto a film - Google Patents

Abstract

An apparatus (10) for feeding strip material (11; 12) and a method for feeding the strip, providing the presence of two distinct spools (B1, B2) of the same strip material.

Description

“APPARATUS AND METHOD FOR JOINING A STRIP HAVING AN ADHESIVE FACE ONTO A FILM”

FIELD OF THE INVENTION

The present invention concerns an apparatus for joining a strip having an adhesive face onto a film, and a corresponding method.

BACKGROUND OF THE INVENTION

Automatic packaging equipment containing one or more units for feeding strip material with an adhesive face, in which this material is unwound from a spool, has long been known. To optimize the productivity of this equipment, one objective is to have as few interruptions as possible in the feed of the strip material. This issue is especially relevant when the spool is about to run out and needs replacing.

For this purpose, feed units and spool replacement methods are known which provide that the feed unit is equipped with two spools of strip material. A first spool is in operation, that is, the material is unwound therefrom, while the second spool is not in use, but it is ready for use so that it can be used as soon as the first spool runs out.

To maintain continuity in the feed of material, the initial end of the ready-to-use spool is taken and connected to the material unwound from the first spool during the equipment’s operation. There is therefore continuity between the first strip and the second strip of material, so that when the first one runs out, the second strip is already present. This replacement mode is known as “on-the-fly changeover”.

A peculiarity of the state of the art is that this spool changeover mode requires the intervention of an operator who has to prepare the join, which is then performed automatically, at the appropriate time, by the machine.

A disadvantage of the known method and equipment is that this is very difficult to perform if the unwound material has an adhesive face. The presence of an adhesive face, in fact, makes the operations of connecting the material of the new spool to the material of the first spool much more difficult, because the adhesive face makes connecting the strips of the two spools, while at the same time keeping the effectiveness of the adhesive face’s adhesion, complex. One aspect to consider is also the orientation of the adhesive face that has to be kept so that it can interface correctly with the elements to which the strip needs to adhere.

Another disadvantage of the known method and equipment is that they require an operator’s manual intervention, which can result in a slowing down of the material feed.

JP-B2-4699315 discloses an apparatus and method for providing a protective film having an adhesive face on a base film. The apparatus comprises two distinct protective film application stations so as to apply two such protective films, each one on a respective surface of the base film. The two application stations are not equipped with a respective application device capable of applying the respective protective film directly onto the base film.

GB-A-1146141 discloses an apparatus provided with two stations for applying two respective paper films onto a strip of flexible and adhesive material. The two paper films are to be applied each onto a respective face of the flexible strip.

There is therefore the need to perfect an apparatus for joining a strip having an adhesive face onto a film and a method for joining a strip having an adhesive face onto a film that can overcome at least one of the disadvantages of the state of the art.

In particular, one purpose of the present invention is to provide an apparatus for joining a strip having an adhesive face onto a film and to perfect a method for joining a strip having an adhesive face onto a film that allow to apply the second strip directly onto the film, instead of onto the first strip.

Another purpose of the present invention is to provide an apparatus and to perfect a method that allow to start applying the second strip automatically, without requiring an operator’s intervention.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims. The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.

In accordance with the above purposes and to resolve the technical problem described above in a new and original way, also achieving considerable advantages compared to the state of the prior art, an apparatus according to the present invention for joining a strip having an adhesive face onto a film advancing along a feed direction comprises a film unwinding station from which the film is fed along the feed direction, a first and a second strip feed stations configured to respectively feed a first and a second strips having a respective adhesive layer on one of their faces.

In accordance with one aspect of the present invention, the apparatus further comprises a first and second application stations distinct from one another and configured to alternatingly attach the first and second strips onto the film advancing along the feed direction, the first and second application stations comprising a respective first and second application devices which have a respective first and second application members configured to be movable between a respective active position in which the respective strip is brought in contact with the film, and a respective inactive position in which the respective strip is kept away from the film.

The apparatus further comprises a controller operatively associated with the first and second application devices and programmed to operate the first and second application devices in a synchronized manner in order to move the first application member from the active position to the inactive position, when the first strip has run out, and the second application member from the inactive position to the active position, in order to replace the application of the first strip with the application of the second strip to the film.

In accordance with the above purposes and to resolve the technical problem described above in a new and original way, also achieving considerable advantages compared to the state of the prior art, a method according to the present invention for joining a strip having an adhesive face onto a film advancing along a feed direction, by means of an apparatus as disclosed above, comprises applying onto the film either the first strip unwound from a first spool at the first application station, or the second strip unwound from a second spool at the second application station.

According to one aspect of the invention, when the first or second strip runs out, the method comprises a step of commanding the respective application device which is in the active position to move in the inactive position, and the other application device which is in the inactive position to move in the active position.

DESCRIPTION OF THE DRAWINGS

These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of an embodiment, given as a non-restrictive example with reference to the attached drawings wherein figs. 1- 3 are front schematic views of a feed unit according to the present invention for feeding strip material unwound from a spool, shown in three successive operating steps of the spool change method according to the present invention.

We must clarify that the phraseology and terminology used in the present description, as well as the figures in the attached drawings also in relation as to how described, have the sole function of better illustrating and explaining the present invention, their purpose being to provide a non-limiting example of the invention itself, since the scope of protection is defined by the claims.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can be conveniently combined or incorporated into other embodiments without further clarifications.

DESCRIPTION OF AN EMBODIMENT OF THE PRESENT INVENTION

With reference to the drawings, an apparatus 10 according to the present invention is provided for joining a strip 11, 12 unwound from a respective spool Bl, B2 onto a film F.

The strip is of the type having an adhesive face so as to adhere to the film F, fed continuously, from a respective spool B3, along its own advance path that passes through the feed unit 10, following its own feed direction A.

For example, the strip can be provided to act as a tearing or opening member on a package, for example known as a “tear tape”.

The apparatus 10 can be part of a packaging plant equipped with various operating stations, wherein the film F of base material, typically a wrapping material, is fed along the feed direction A, in succession through the various operating stations, which include the feed unit 10 (fig. 1). The apparatus 10 comprises an unwinding station G, which comprises means for supporting the spool B3 and allowing it to be unwound along the feed direction A.

The feed unit 10 comprises a first station 13 for feeding the first strip 11 and a second station 14 for feeding the second strip 12. These first and second feed stations 13, 14 each consist of a respective spool support member, configured to rotatably support a corresponding spool Bl, B2. In particular, the spool support member can be a roller.

In a known manner, the apparatus 10 comprises a first strip application station S 1 at which a first strip 11 , fed from the first spool B 1 , is applied to the film F, in particular adhered thereto by placing its adhesive face in contact with the film F. The first application station S 1 is realized with a first counter-roller 15 on which the film F rests while it advances.

For this purpose, at the aforementioned first application station S 1 , the apparatus 10 comprises a first application device 100, to which the first strip 11 is fed, configured to apply, that is, press, the strip 11 against the film F. The first application device 100 comprises a first lever 101 pivoted to a support block 102 so as to be pivotable about a rotation axis R1 in a longitudinal plane, or a plane aligned with the feed direction A of the film F. A drive member 103 is provided in the support block 102, connected to the first lever 101 so as to drive its rotation about its rotation axis Rl.

The first lever 101, which in the example shown is in the form of an arm pivoted at a first end 101 A thereof, comprises a member 104 for applying the strip 11 onto the film F, configured to bring the first strip 11 in contact with the film F at the first application station SI, in particular at the first counter-roller 15.

The application member 104 comprises a first roller 105 pivoted to the first lever 101 and rotatable about its rotation axis R2, parallel to the rotation axis Rl .

The first roller 105 is configured to retain the first strip 11, and for this purpose it is connected to a suction system 106 that defines means for retaining the first strip 11. The retention by suction allows the strip 11 to be retained in a simple and effective manner, without the risk of damaging it.

Advantageously, the first roller 105 is pivoted in proximity to a lateral edge of the first lever 101, so as to have at least a part of its perimeter surface protruding with respect to the first lever 101, toward the first counter-roller 15. This guarantees that the first roller 105 contacts the film F and the first counter-roller 15, without the body 101 abutting against the film F.

The first application device 100 also comprises a return member 107, which comprises a return roller 108 rotatable about its own rotation axis R3, parallel to the rotation axis R2 of the first roller 105 and to the rotation axis R1 of the first lever 101. The return roller 108 is preferably pivoted at the second end 10 IB of the first lever 101. In other embodiments, not shown, the return roller 108 can also not be associated with the first lever 101, providing it is still positioned between the first feed station 13, or the first spool Bl, and the application member 104.

In this way, the return roller 108 allows to guide the first strip 11, arranged downstream of the application member 104, in a direction consistent with the advance of the film F.

In an intermediate position between the first feed station 13, which comprises the first spool Bl, and the first application device 100 there is provided a cutting device 109 configured to cut the strip 11. This allows to have better control during the phase in which the strip 11 is running out, thus being able to facilitate the spool changeover without interrupting the application onto the film F.

In accordance with the present invention, the apparatus 10 comprises a second station S2 for applying the strip onto the film F. The second application station S2 is realized with a second counter-roller 16 which, in the example shown, is located along the advance path of the film F, so that the latter rests on it during the advance, and upstream of the first application station S 1 with respect to the feed direction A of the film F.

Alternatively, a single counter-roller can also be provided on which two distinct application positions of the strips 11, 12 are obtained.

A second application device 200, similar to the first 100, is provided at the second application station S2, configured to apply a second strip 12 of material, wound from a second spool B2, onto the film F. Obviously, the material of the first 11 and the second strip 12 is the same, in order to guarantee the continuity of its application onto the film F.

The second application device 200 comprises a second lever 201, preferably in the form of an arm, or in any case oblong, which is pivoted, at a first end 201 A thereof, on a support block 202. The second lever 201 is pivotable about a rotation axis R4 parallel to the rotation axes Rl, R2, R3 described in relation to the first application device 100.

We must clarify that the second application device 200 is equipped with its own drive member 203, independent of the drive member 103 of the first application device 100. The second drive member 203 is housed in the support block 202.

The second application device 200 comprises, as an application member 204, a second roller 205 pivoted to the second lever 201 and rotatable about a rotation axis R5 parallel to the rotation axis R4. The second roller 205 is suitably pivoted in proximity to a lateral edge of the second lever 201, so that at least part of its perimeter edge protrudes laterally from the second lever 201 in the direction of the second counter-roller 16.

This application member 204 is also connected to a suction system 206, which defines means for retaining the strip 12 on the perimeter edge of the second roller 205. Given that, in this example, the second feed station 14, which comprises the second spool B2, is located upstream of the second application device 200, with respect to the feed direction A of the film F, the second strip 12 reaches the second application device 200 already correctly oriented to be applied onto the film F. The suction system 206 therefore allows to keep the second strip 12 in position against the roller 205 until it is to be applied onto the film F.

The second application device 200 is also provided with a cutting device 209 located in an intermediate position between the second feed station 14 and the application member 204 with respect to the feed of the second strip 12.

Both the first application device 100 and also the second application device 200 are movable between an active position, in which each of them is configured to apply the corresponding strip 11, 12 onto the film F, and an inactive position, in which the respective strip 11, 12 is kept away from the film, at the corresponding application station SI, S2.

In particular, in the active position, the respective application member 104, 204 brings the respective strip 11, 12 in contact with the counter-roller 15, 16, and therefore with the film F. In the inactive position, on the other hand, the corresponding application member 104, 204 is away from the counter-roller 15, 16 or from the film F, and therefore does not bring the respective strip 11, 12 in contact therewith.

In particular, the active position is obtained by making the first 101 and second 201 levers rotate about the respective rotation axis Rl, R4, toward the corresponding counter-roller 15, 16, that is, by bringing the body 101, 201 into a lowered position. On the contrary, the inactive position is obtained by making the first 101 and second 201 levers rotate about the respective rotation axis Rl, R4, away from the corresponding counter-roller 15, 16, that is, bringing it into a raised position, considering the example shown in the drawings.

From the above description, it can be concluded that the apparatus 10 comprises two strip application devices 100, 200, each application device being placed at a respective one of the two application stations SI, S2. Each application device 100, 200 is fed with the strip of a respective spool of either the first spool B 1 or the second spool B2. Each application device 100, 200 defines a respective feed path for its strip, starting from the corresponding first or second spool Bl, B2.

It can also be concluded that each application device 100, 200 comprises a respective lever 101, 201 pivoted and cantilevered in a plane aligned with, or longitudinal to, a feed path of the film F. Advantageously, each application device 100, 200 comprises an application member 104, 204 configured to apply the strip against the film F, in particular at a respective application station SI, S2. The application member 104, 204 is preferably equipped with a suction system 106, 206 for retaining the strip material against it, more precisely against its perimeter edge.

The apparatus 10 further comprises a controller 20, or control unit, operatively connected to both the application devices 100, 200. The controller 20 is programmed to command the application devices 100, 200 so as to move them in a synchronized manner between their respective active position and their respective inactive position. In particular, the control unit 20 is associated with the two drive members 103, 203 of the application devices 100, 200.

In particular, the controller 20 can be programmed to move the first application member 104 from the active position to the inactive position when the first strip 11 runs out, and the second application member 204 from the inactive position to the active position when the first strip 11 runs out, or when the first application device 100 is moved from the active position to the inactive position. Obviously, the controller 20 is programmed to move the two application devices 100, 200 in the opposite direction when the second strip 12, applied by the second application device 200, runs out.

In the example shown, the controller 20 is further operatively associated with the first 109 and second 209 cutting device so as to perform the cut respectively of the first 11 and second 12 strip, before moving the respective first 104 and second 204 application member from the respective active position to the inactive one.

The operation of the apparatus 10 described heretofore, which corresponds to the method according to the present invention, comprises the following steps.

The method provides to apply onto the film F of base material, the strips 11, 12 unwound from the two spools Bl, B2 in a synchronized manner, each at a respective application station SI, S2.

In particular, the method provides to apply the first strip 11 , unwound from the first spool Bl, onto the film F at the first application station SI (fig. 1). In this step of applying the first strip 11, the first application device 100 is in the active position, while the second application device 200 is kept in the inactive position.

When the first spool Bl runs out, as shown schematically in figs. 1 and 2, a corresponding end-of-strip signal is emitted. This signal is emitted by the apparatus 10 itself or by the packaging machine on which it is mounted. The running out of the spool, and thus the emission of the signal, is evaluated on a case-by-case basis, on the basis of the strip consumption speed and the amount of strip remaining, which can be evaluated on the basis of its weight or its length, for example.

When the first spool B 1 has run out, therefore when the end-of-strip signal has been emitted, the application of the second strip 12 onto the film F at the second application station S2 is commanded. To do this, the second application device 200 is driven so as to bring it into its active position. Before performing this movement, it is advisable to ensure that the second strip 12 is engaged by the corresponding application member 204, and retained thereby through the suction system 206 (figs. 1 and 2).

When the second strip 12 is ready to be applied, the movement of the second application device 200 into the active position is commanded, advantageously in a synchronized manner with the end of the feed of the first strip 11 , so as to keep the continuity of the strip material along the film F, while preventing any overlap of material.

In order to synchronize the movement of the second application device 200, it is possible to wait for the first strip 11 to run out on its own, or it can be provided to operate a cut of the first strip, by means of the cutting device 109, so as to cause the feed of the first strip 11 to end.

It can be provided to operate the cut of the first strip 11 and, simultaneously, bring the second application device 200 into the active position (and therefore start applying the second strip 12 onto the film F), in particular if the length of the first strip between the cutting means 109 and the first application station S 1 corresponds to the distance between the two application stations SI, S2.

More generally, the beginning of the application of the second strip 12 is synchronized with the arrival of the end of the first strip 11 at the first application station S 1 , which is downstream of the second application station S2 with respect to the film feed direction A.

After the second application device 200 has been brought into the active position, a transient phase occurs in which the application of the second strip 12 begins and the application of the first strip 11 ends. In this transient phase, both application devices 100, 200 are in the active position (fig. 2).

Once the feed of the first strip 11 has finished, the first application device 100 is commanded so as to move it into the inactive position (fig. 3), while the strip material is unwound from the second spool B2 and applied at the second application station S2.

In the meantime, the first spool B 1 can be changed, by removing the recently finished spool from the respective feed station 13 and inserting a new one.

Vice versa, when the second spool B2 has run out, the first application device 100 is prepared, bringing the free end of the first strip 11 in contact with the application member 104, making it pass around the return member 107 if necessary, and retaining it in contact with the perimeter edge of the application member 104, thanks to the suction system 106.

The first application device 100 is then moved into its active position, in a manner synchronized with the running out of the second strip 12. The feed can cease due to the second spool B2 running out completely, or it can occur after the second strip 12 has been cut by means of the cutting device 209.

Since the second strip 12 is applied onto the film F in a position upstream of the first application station S 1 , it is possible that there is a waiting time between the application of the second strip 12 ending and the feed of the first strip 11 beginning. In this case, the synchronization between the two can be achieved by monitoring the arrival of the end of the second strip 12 at the first application station SI. It can therefore be concluded that the start of the feed of one strip 11, 12 has to be synchronized with the passage of the end of the other strip 12, 11 in the application station S 1 downstream of the other application station S2, with respect to the feed direction A of the film F.

It is clear that modifications and/or additions of parts may be made to the joining apparatus 10 and method as described heretofore, without thereby departing from the field and scope of the present invention, as defined by the claims.

It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art will be able to achieve other equivalent forms of apparatus and method for joining a strip having an adhesive face onto a film, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

In the following claims, the sole purpose of the references in brackets is to facilitate their reading and they must not be considered as restrictive factors with regard to the field of protection defined by the claims.

Claims

1. Apparatus (10) for joining a strip (11; 12) having an adhesive face onto a film (F) advancing along a feed direction (A), said apparatus (10) comprising a film unwinding station (G) from which said film (F) is fed along said feed direction (A), a first (13) and a second (14) strip feed stations configured to respectively feed a first (11) and a second (12) strips having a respective adhesive layer on one of their faces, said apparatus (10) being characterized by further comprising a first

(51) and second (S2) application stations distinct from one another and configured to alternatingly attach said first (11) and second (12) strips onto the film (F) advancing along the feed direction (A), said first (SI) and second (S2) application stations comprising a respective first (100) and second (200) application devices which have a respective first (104) and second (204) application members configured to be movable between a respective active position in which the respective strip is brought in contact with the film (F), and a respective inactive position in which the respective strip is kept away from the film (F), and by further comprising a controller (20) operatively associated with the first (100) and second (200) application devices and programmed to operate said first (100) and second (200) application devices in a synchronized manner in order to move the first application member (104) from the active position to the inactive position, when the first strip (11) has run out, and the second application member (204) from the inactive position to the active position, in order to replace the application of the first strip (11) with the application of the second strip (12) to the film (F).

2. Apparatus (10) as in claim 1, characterized in that said first (104) and second (204) application members respectively comprise a first (105) and a second (205) rollers rotatable mounted on a respective first (101) and second (201) levers, said first (101) and second (201) levers being pivotable mounted to respectively move the first (105) and second (205) roller between the inactive position and the active position.

3. Apparatus (10) as in claim 2, characterized in that said first (SI) and second

(52) application stations (100, 200) further comprise a respective first (15) and second (16) counter rollers configured to be contacted by the respective first (105) and second (205) rollers in said active position with the film (F) therebetween.

4. Apparatus (10) as in claim 2 or 3, characterized in that said first (105) and second (205) rollers are connected to a respective suction system (106, 206) to retain the respective first (11) and second (12) strip when in the inactive position.

5. Apparatus (10) as in any of the claims 2 - 4, characterized in that said first (101) and second (201) levers are rotatable about a respective first (Rl) and second (R4) axes of rotation parallel to each other.

6. Apparatus (10) as in any of the preceding claims, characterized in that said controller (20) is configured to operate said first (100) and second (200) application devices independently from one another.

7. Apparatus (10) as in any of the preceding claims, characterized by further comprising a first (109) and a second (209) cutting devices configured to cut the respective first (11) and second (12) strips upstream of the respective first (100) and second (200) application devices.

8. Apparatus (10) as in claim 7, characterized in that said controller (20) is further operatively associated with the first (109) and the second (209) cutting device so as to perform the cut respectively of the first (11) and second (12) strip before moving the respective first (104) and second (204) application member from the respective active position to the inactive one.

9. Apparatus (10) as in any of the preceding claims, characterized in that said first (SI) and second (S2) application stations are arranged along the feed direction (A) next to each other.

10. Method for joining a strip (11 ; 12) having an adhesive face onto a film (F) advancing along a feed direction (A) with an apparatus (10) as in any of the previous claims, said method comprising applying onto the film (F) either the first strip (11) unwound from a first spool (Bl), at the first application station (SI), or the second strip (12) unwound from a second spool (B2) at the second application station (S2), characterized in that, when said first (11) or second (12) strip runs out, the method comprises a step of commanding the respective application device (100, 200) which is in the active position to move in the inactive position, and the other application device (100, 200) which is in the inactive position to move in the active position.