EP4163239A1

EP4163239A1 - System for unwinding and quick change of reels in a line for manufacturing a sheet product

Info

Publication number: EP4163239A1
Application number: EP21201834.5A
Authority: EP
Inventors: Carlo Comerio
Original assignee: RODOLFO COMERIO Srl
Current assignee: RODOLFO COMERIO Srl
Priority date: 2021-10-11
Filing date: 2021-10-11
Publication date: 2023-04-12
Anticipated expiration: 2041-10-11
Also published as: EP4163239B1

Abstract

System for unwinding and quick change of reels of a sheet product in a continuous production line, wherein two unwinding trolleys (5, 6) are used respectively in a running and reserve position, each carrying a product reel on a pneumatically tiltable shaft, wherein the pneumatic movement of the shaft brings the running reel in close contact with the reserve reel, so as to form a junction and connect the second reel to the line automatically, leading to the depletion of the inline reel or to the cutting of the tail of the inline reel.

Description

Field of application

The invention relates to the field of industrial lines for the continuous production of laminated sheet products, typically represented by multilayer laminates for various technical uses. The invention relates in particular to a system for the unwinding and quick change of reels.

Prior art

The industry makes extensive use of multilayer technical laminates known as "sheets". An example of considerable industrial interest is represented by so-called rubberised fabrics or, more generally, by products comprising a support layer and an elastomer layer (called "rubber" for simplicity) applied to one or both faces of the support. The sandwich thus obtained is used in the industry mainly for the manufacturing of components of tyres for vehicles, as well as for other applications such as conveyor belts, transmission belts, etc.
It is advantageous to manufacture such products in lines that operate continuously, with clear advantages in terms of productivity. Typically these lines are calendering lines where the process steps include passing the product between pairs of rollers. For example, a calendering operation can be used to couple two layers together, or to apply an elastomer layer on a textile or metal substrate.
The materials used in the process are typically wound in reels and, from them, continuously fed to the line by means of suitable unwinders. An unwinder is generally adapted to support a product reel and to feed the line with the product unwinding from said reel.
When the sheet product has sticky surfaces, for example because it comprises a surface layer of soft elastomer, it is necessary to prevent the product from adhering to itself, which could make the reels useless. For this purpose, it is known to form reels of product using a so-called service wrap, which can be for example a suitable fabric. Each turn of the reel is formed by interposing the service wrap between the adjacent layers of product, so that the product is wound always in contact with said service material and not with itself.
In this context, the problem of speeding up the reels changing operation arises, i.e. the problem of how to replace a depleted reel with a new one, without affecting the production process.
In the prior art the production is interrupted, a new product reel is put in place, a junction is made between the tail of the old reel still fitted into the line and the leading end of the new reel, all with a substantially manual process that is time-consuming. During this time, either production must be stopped, or a buffer accumulator capable of temporarily feeding the line must be provided, said accumulator however must be of a large size to cover the time required for the changing of the reel and therefore represents a considerable cost.
Handling the reels is a complex operation that must be performed with caution because the sheet product is delicate, especially when having a considerable width and/or has a sticky surface. Products of interest for tyre manufacturing, including rubberised fabrics, are notoriously difficult and delicate to handle. The reels have generally a diameter of about 1 metre and, consequently, they have a considerable weight. The junction between the tail end of the depleted reel and the leading end of the new reel is generally performed manually with the aid of a press and takes a considerable amount of time. In addition, for obvious cost reasons, there is a need to recover the service wrap removed from the depleted reel, so that the service wrap can be reused.
The still essentially manual nature of the junction makes the operation relatively time-consuming and prone to errors.

Summary of the invention

The invention addresses the technical problem of how to make the above described reel changing operation easier and quicker. The invention aims to speed up the reel change operation to reduce the impact on the process and, in particular, to reduce the size of the buffer accumulator which is required to avoid interruption of the production process during the change. Furthermore, the invention aims to automate the reel changing operation to make it repeatable and less prone to human error.
The aims are achieved with a system for unwinding and quick change according to claim 1. The invention also relates to a process for the change of a reel according to the claims.
The system of the invention uses at least one pair of unwinders.
A first unwinder is in running position and carries a first product reel that feeds the line. Said first reel can be termed inline reel. A second unwinder is in a standby position and carries a second reel of said product, which is not connected to the line (i.e. not fitted) and can be referred to as a reserve reel.
At least one of said two unwinders, preferably both, comprises a movable reel shaft on which the respective product reel is mounted.
Said two unwinders are placed side by side and positioned with the respective facing product reels, at a distance such that a movement of said movable shaft can bring the inline reel and the reserve reel to contact with each other, so as to form a junction between a tail of the in-ine reel and a head of the reserve reel. Said junction allows the inline insertion of the second reel to replace the first one.
In the invention, the junction between the tail of the inline reel and the head of the reserve reel is achieved thanks to the movable shaft which brings the reels into contact with each other, with adequate pressure. The movable shaft can be, for example, pneumatically driven.
Adhesion between the reels may be provided by an adhesive property of the product itself and/or by an adhesive applied on one of the reels for this purpose. The product may have sufficient adhesive property to create a junction, for example if it has a soft elastomer-coated surface. If necessary or preferred, it may be envisaged to apply an adhesive means, preferably a double-sided tape, on the tail of the first reel and/or on the head of the second reel. If used, said adhesive means is preferably applied on the head of the reserve reel which can be handled while the other one is running, or can be prepared in advance with the adhesive means.
The invention achieves the above-mentioned aims. In particular, the reel change operation can be carried out in a short time and almost automatically, reducing the manual intervention. Note that the inline reel is stopped only for the short time necessary to place it on the new reserve reel and then production is resumed immediately.
The invention provides an automatic joining system by contact, making use of the adhesiveness of the product or, if necessary, of an additional adhesive means, to join the tail of the inline reel to the head of the new reel.
Moreover, in the frequent case in which a service wrap is used, the invention facilitates the recovery thereof as will be explained in more detail below. This is advantageous because the service wrap has a cost and there is an interest in its reuse.

Detailed description of the invention

A particularly interesting application of the invention relates to the lines that produce products for the manufacture of vehicle tyres. Such products may be, for example, plies for manufacturing specific parts of tyre.
In the applications in which the product is wound with interposition of a service wrap, said unwinders each comprise a further shaft to support a reel of collection of the service wrap during the unwinding of the product.
The system includes at least one pair of unwinders. In practice, a larger number of such groups can also be envisaged according to requirements. The line has a suitable feeding zone suitable for receiving at least two unwinders, that is, the unwinder running with the inline reel and a reserve unwinder.
Advantageously, the system of the invention uses two or more interchangeable unwinders, each provided with a movable shaft for supporting the product reel.
The unwinders alternate in the role of running unwinder and reserve unwinder. In other words, after a junction has been performed in the manner described above, the unwinder that was set up as a reserve becomes the running unwinder; similarly, the unwinder that was previously running, which for sake of simplicity is termed depleted unwinder, can be removed from the line, prepared with a new product reel, and repositioned in the line where it will act as a reserve.
The depleted unwinder, after the change has been completed, is advantageously displaced to another area to recover the service wrap, if any, and to prepare the new product reel, then it is brought back in line and placed in the reserve position.
With only two unwinders available, of course, each unwinder will alternate between the position in use and the reserve position. With a greater number of unwinding groups they can be used in rotation.
A pair of unwinders, suitably positioned in line, forms an unwinder group capable of performing an automatic joint by contact.
The term "movable shaft" means that the axis of the shaft has a degree of freedom of movement with respect to a frame of the respective unwinder. This means that the shaft, in addition to rotation around its own axis, can also move with respect to a frame of the unwinder frame. Said movable shaft is preferably tilting. In this case, the axis of the shaft can travel a circular arc-like trajectory with respect to a horizontal fulcrum axis.
The movable shaft is preferably with pneumatic actuation, for example with a suitable cylinder-stem type actuator.
The movable shaft can be made by providing a suitable system for moving the supports of the shaft. In a preferred embodiment, the movable shaft is supported by two shoulders positioned on opposite sides of the unwinder, each of said shoulders having a base hinged to the frame of the unwinder and a head carrying the shaft. In this embodiment, the movable shaft can be effectively controlled with a pair of pneumatic actuators, each having the cylinder hinged to a fixed part of the frame and the stem hinged to one of said shoulders, or vice versa.
The thrust provided by the movable shaft is determined so as to cause the desired junction by adhesion. The unwinders are suitably held in place in the direction of the thrust, so that the force is transmitted to the reels.
An unwinder for use in the system of the invention therefore comprises, in a particularly preferred embodiment: a frame; a first shaft to support the product reel; a second shaft to accommodate the service wrap as the product is being unwound; a pair of supports of the first shaft that are hinged to the frame with a tilting movement; and a pair of pneumatic actuators arranged to control said tilting movement of the supports of the first shaft.
In a preferred embodiment, the unwinders are shaped like trolleys. Preferably, the unwinding trolleys are wheeled to facilitate handling in the production site.
The unwinders can be inserted in the line and removed from the line on dedicated guides. Preferably, said unwinders can be inserted/extracted laterally with respect to a direction of transport of the product, which is the longitudinal direction along which the line itself is predominantly developed.
The unwinders also comprise the motors and transmission groups necessary to rotate the shafts, unwind the product and collect the service wrap.
The reel change process includes positioning two unwinders of the type described above in a suitable feeding zone of the line, one acting as a running unwinder, with inline reel, and one acting as a reserve reel, ready to replace the inline product reel when the latter is close to depletion.
The process for a quick change comprises, in order, the operations of:

temporarily stopping the unwinding of the inline reel;
controlling a displacement of said movable shaft in such a way as to bring said reels to contact with each other and to form a junction by adhesion between the tail of the inline reel and the head of the new reel;
disconnecting the depleted reel from the line and continuing the production by feeding the product from the new reel, which becomes the reel currently in the line, replacing the previous one.

Preferably both unwinders carry the product reel on a movable shaft. Preferably, the junction is made by actuating a movable shaft of the inline reel, i.e. the reel is displaced in line, now almost depleted, causing it to extend towards the new reel. In fact, it is preferable to displace the depleted reel which has a lower mass and inertia. Once the junction has been made and, if necessary, after the tail of the depleted reel has been cut off, the shaft returns to the initial position.
The adhesion between product surfaces may be caused partly or wholly by an adhesive property of the product surface. This adhesive property may be due to a soft elastomer layer present in the product. For example, the applicant has noted that rubberised fabrics used in the field of tyre manufacture lend themselves to the application of the invention and generally have an adhesiveness such as to create a sufficiently stable junction. The adhesion can also be partially or wholly caused with a suitable adhesive means positioned on the product surface of one of the two reels. In this case, it is preferable to position a double-sided tape on the head of the reserve reel.
The operation of disconnecting the depleted reel from the line leads to the depletion of the inline reel or comprises the step of cutting off a tail of the inline reel after forming the junction. The respective unwinder can be separated from the line and taken to the appropriate working area where the service wrap is recovered and a new product reel is mounted. Once this is done, the unwinder may be repositioned as a reserve. It is understood that the invention also improves and rationalises the handling of the unwinders within the production site, and the management of the service wrap.

Description of the figures

The invention is now described with reference to a preferred embodiment and with the aid of the figures, in which:

Fig. 1 shows schematically, in a side view, a production line provided with two unwinders for reel change, in accordance with one embodiment of the invention.
Fig. 2 shows the group of the two unwinders of Fig. 1 in more detail.

Fig. 1 shows, in a simplified manner, a portion of a production line 1 in which a sheet of elastomeric material 2 is intended to be coupled to a product 3 represented by a rubberised fabric, also called "ply" in the technical field. Said product 3 more precisely is formed by a textile support to which an elastomer layer has been applied on one or both surfaces. The sheets 2 and 3 are carried by belts 20 and 21 shown schematically in Fig. 1.
The product resulting from the coupling between the sheet 2 and the rubberised fabric or ply 3 typically serves for the production of parts of tyres. The coupling between the sheets 2 and 3 is achievable with known techniques and is not shown in the figure.
It should be noted that the particular technical application is not limiting to the purposes of the invention. It is relevant, for the understanding the invention, to note that the product 3 is fed by a reel 4 mounted on a first unwinding trolley 5. Adjacent to said first unwinding trolley 5 is located an identical second unwinding trolley 6, which carries a reel 7 for replacing said product 3.
The unwinding trolleys 5 and 6, thus positioned, form an unwinding group provided with an inline reel, which in the example is the reel 4, and with a reserve reel, which in the example is the reel 7. The reel 4 is suitably fitted so that the product 3 unwound from said reel 4 can feed the process through the belt 21.
The line 1 has a zone 8 that is suitably arranged to accommodate said unwinding trolleys 5 and 6. In the example, the trolleys are provided with wheels and can be extracted laterally from the line on guides 9 obtained in the flooring 22 of the installation room.
The product 3 has sticky surfaces, due to the elastomer layers, therefore the reels 4 and 7 are wound on a service fabric. The unwinding trolleys 5 and 6 are consequently structured to collect the service fabric as the product 3 is being unwound.
Fig. 1 shows a condition in which the reel 4 is in line and feeds the process, however it is close to depletion as can be understood by noting the small diameter of the reel.
This condition is better visible by referring to Fig. 2. In said Fig. 2 it can be noted first of all that the unwinding trolley 5 comprises a frame 10; a first support 11 for a shaft 12 of the product reel; a second support 13 for a shaft 14 of the service fabric.
The shafts 12 and 14 are rotated by motors and transmission groups, on board the trolley 5, which for the sake of simplicity are not shown in the figures.
The inline reel 4 is almost depleted, the dashed line 4' which indicates the size of the new reel can be noted for comparison. It should also be noted that the product 3, which is sent to the production line, and the service fabric 15, which is wound on a reel 16 around the shaft 14, are simultaneously unwound from the reel 4.
In the condition of Fig. 2, as the reel 4 is almost depleted, the service fabric 15 is almost all collected in the reel 16 which therefore has a diameter close to the maximum. Note the line 15' which indicates the path of the service fabric under conditions of new product reel. The service fabric 15 is guided by suitable rollers 30, 31 which are positioned to allow a correct winding angle as the diameter of the product reel varies.
The support 11 is tiltable with respect to the frame 10 around a fulcrum 17. Said movable support 11 can substantially follow a circular arc-like trajectory with respect to a horizontal axis passing through the fulcrum 17 and perpendicular to the plane of Fig. 2. The movement of the support 11 with respect to the frame 10 is pneumatically controlled. As a result of this degree of freedom of the support 11, the shaft 12 is also tiltable with respect to the frame 10 of the trolley.
The unwinding trolley 6 does not need to be described because constructively it is the same as the unwinding trolley 5. It should be noted that the trolleys 5 and 6 are positioned opposite each other in a specular arrangement, so that the reels 4 and 7 face each other and at a short distance. As far as the unwinding trolley 6 is concerned, it is sufficient to note that it carries the new product reel 7; the respective reel 18 of the service fabric is at the minimum size since obviously the service fabric is wound in the reel 7 together with the product 3. The line 18' shows the size that the service fabric reel will assume at the end of the unwinding.
In Fig. 2 it can be seen that the pneumatic tilting movement of the shaft 12, to the left in the figure, brings the inline reel 4 into contact with the new reel 7. The contact causes adhesion between respective surfaces of the product 3 with the effect of forming a junction between the tail of the reel 4 and the head of the reel 7. For example in Fig. 2 a junction is formed along the contact line 19.
In Fig. 2 the arrow A indicates the movement of the support 11 around the fulcrum 17. It should be noted that the shaft 12, and with it the reel 4, extend towards the new reel 7 placed frontally, obtaining the desired effect of substantially automatic joint between the depleted reel and the new reel.
Said junction is caused by the pneumatic thrust, which brings the product surfaces into contact with each other with adequate pressure, and by the adhesive properties of the product itself. Alternatively, or in addition to the adhesive properties of the product, a double-sided adhesive can be applied on the surface of the product 3 to facilitate the junction.
Clearly, the junction is formed after temporary stop of the reel 4.
Once the junction is formed, the reel 7 is able to feed the product 3 to the line, i.e. it becomes the new inline reel. The unwinding trolley 5 can be extracted laterally from the line to remove the reel 16 of service fabric, to be recovered for later use, and to prepare a new product reel on the shaft 12. With this set up, the trolley 5 can be moved back into position, opposite the trolley 6. There will therefore be a specular situation with respect to that of Fig. 2, in which, once the reel 7 has been consumed, the pneumatically driven shaft of the trolley 6 is activated to make the junction with the new reel mounted on the trolley 5.
The pneumatic actuators are not shown in the figures for the sake of simplicity. For example, one or more pneumatic actuators can be provided in each of the trolleys having a cylinder pivoted to a suitable fixed part of the frame 10 and a stem pivoted to the support 11.

Claims

System for unwinding and quick change of reels of a sheet product (3) fed to a continuous production line (1), wherein:
said system comprises at least one pair of unwinders of which a first unwinder (5) is in a running position and carries a reel (4) of inline product, and a second unwinder (6) is in a reserve position and carries a reserve reel (7) of said product, which is not connected to the line;

wherein at least one of said two unwinders comprises a movable shaft (12) on which the respective product reel is mounted;

and wherein said two unwinders are placed side by side and positioned so that the respective product reels face one another, at a distance such that a movement of said movable shaft (12) can bring said inline reel (4) and said reserve reel (7) to contact with each other to form a junction (19) between a tail of the inline reel and a head of the reserve reel, so as to allow the inline insertion of the reserve reel to replace the previous one.
System according to claim 1, wherein said product (3) comprises an outer layer having adhesive properties, the adhesion between the surfaces and the consequent junction being caused by said adhesive property of the product, and/or with the addition of an adhesive, particularly a double-sided adhesive, which is preferably positioned on the tail portion of the inline reel.
System according to claim 1 or 2, wherein said product (3) is wound in reels with interposition of a service wrap (15), adapted to avoid adhesion of the product on itself, said first unwinder (5) and second unwinder (6) each comprising a shaft (14) to support a reel (16) collecting the service wrap.
System according to one of the preceding claims wherein said movable shaft (12) is tiltable with respect to a frame (10) of the respective unwinder.
System according to claim 4, wherein said movable shaft (12) is supported by two shoulders (11), positioned on opposite sides of the unwinder, each of said shoulders having a base hinged to the frame of the unwinder and a head supporting said shaft (12).
System according to one of the preceding claims, wherein said shaft (12) is movable with pneumatic actuation.
System according to one of the preceding claims, wherein said two unwinders (5, 6) are interchangeable, each comprising said movable shaft (12) for the product reel, and each of said two unwinders is usable both as a running unwinder for feeding product and as a reserve unwinder.
System according to one of the preceding claims wherein said unwinders (5, 6) are configured as trolleys.
Process for changing a feeding reel of a sheet product (3) to a continuous production line (1), wherein:
in a feeding zone (8) of the line (1), a pair of unwinders (5, 6) is provided, of which:
a first unwinder (5) carries a first reel (4) of said product and acts as a running unwinder, feeding the line with the product unwinding from said first reel;

a second unwinder (6) carries a second reel (7) of said product and acts as a reserve unwinder, said second product reel not being connected to the line;

wherein at least one of said unwinders comprises a movable shaft (12) for the respective product reel;

said first unwinder and second unwinder are placed side by side and

positioned with the respective product reels facing one another, said product reels being at a distance such that a movement of said movable shaft can bring them into contact;

and where the process for a quick changing comprises, in order, the operations of:
i) temporarily stopping the unwinding of the first reel (4) which is inline;

ii) controlling a displacement of said movable shaft in such a way as to bring said reels (4, 7) into contact with each other, with a contact pressure adapted to cause a junction by adhesion between a tail of the first reel (4) and a head of the second reel (7);

iii) disconnecting the first reel from the line.
Process according to claim 9, wherein the first unwinder is provided with a movable shaft and the operation ii) comprises a displacement of said movable shaft so that the inline reel extends towards the reserve reel until it causes the contact and forms the junction.
Process according to claim 9 or 10, wherein during operation ii) the adhesion between surfaces of the product is caused by an adhesive property of the product surface and/or by effect of an adhesive positioned on the product surface of one of the two reels.
Process according to one of claims 9 to 11 wherein the operation iii) leads to the depletion of the inline reel or it comprises the step of cutting a tail of the inline reel.
Process according to one of claims 9 to 12 wherein said two unwinders are constructively interchangeable, each comprising a movable shaft (12) for the respective product reel, and each of said two unwinders is alternatively used as a running unwinder, carrying the inline product reel, and as a reserve unwinder.
Process according to any one of the claims wherein the unwinders are moved laterally with respect to the line with respect to a longitudinal direction of product advancement.
Process according to any one of claims 9 to 14 wherein said sheet product comprises at least a substrate and an elastomer layer applied on at least one face of the substrate, and wherein said production line is a tyre component production line.
Process according to any one of claims 9 to 15, which is performed using a system according to one of claims 1 to 8.