FI4330006T3

FI4330006T3 - Improved method and apparatus for continuously winding rubber strips to form reels

Info

Publication number: FI4330006T3
Application number: FIEP22730957.2T
Authority: FI
Inventors: Luc Lassalle; Guillaume Paulet
Original assignee: Spoolex
Priority date: 2021-07-27
Filing date: 2022-05-16
Publication date: 2024-11-01
Also published as: EP4330006A1; FR3125738A1; WO2023007062A1; EP4330006B1; FR3125738B1

Description

IMPROVED METHOD AND APPARATUS FOR CONTINUOUSLY WINDING

RUBBER STRIPS TO FORM REELS

Technical Field

[0001] The invention relates to the technical field of manufacturing patties from rubbery material, particularly rubber, used for manufacturing tires, for example.

[0002] The invention particularly concerns a process and installation for the continuous winding of rubber strips to form such patties from a rubber sheet continuously extracted from an extruder. Unlike winding sheets into a coil, winding strips forms patties due to the narrow width of the wound rubber strips.

[0003] By "rubber," we mean a rubber-based paste used in the manufacturing of a tire. This rubber-based paste can incorporate a reinforcement element, such as fabric, cord, cable, or any other structural component or element.

Prior Art

[0004] In the current state of the art, it is known to manufacture a rubber sheet via an extruder. Upon exiting the extruder, the sheet is conveyed through transit and cooling rollers to a first module where the cooled sheet is deposited on a support film, called a "liner," made of plastic or textile material, and then wound into a coil approximately 1600 mm wide.

[0005] In practice, when the rubber coil is completed, the extruder is stopped, the sheet is transversely cut, and the coil is discharged and transported to other machines for coil unwinding, sheet cutting into strips, and strip winding into patties.

[0006] The current configuration is restrictive and presents several disadvantages, particularly related to various coil manipulations, winding and unwinding operations, coil storage and preservation, yield loss due to extruder stoppage, etc.

[0007] The Applicant has already attempted to address these disadvantages with European patent No. EP 3583060, which discloses an installation and a process for continuously winding rubber strips to form patties from a rubber sheet continuously extracted from an extruder.

[0008] The process described in this document includes steps such as: 1

- Continuously feeding and cooling the sheet exiting the extruder via transit and cooling rollers; - Continuously depositing the cooled sheet onto a continuously unwound support film to form a composite; - Passing the composite through an accumulator; - Cutting the composite at its width into a plurality of strips at the exit of the accumulator; - Winding the strips at an initial speed, each around a support to form patties; - When the patties are finished, stopping the winding of the strips and accumulating the composite from the extruder in the accumulator; - While the composite accumulates, supplying empty supports, transversely cutting the strips upstream of the patties, and attaching the free end of the strips to said empty supports; - Simultaneously, finishing the winding of the free end of the strips around the patties, automatically evacuating said patties, and restarting the winding of each of the strips around the empty supports at a speed higher than the initial speed until completely discharging the accumulator, then resuming winding at the initial speed.

[0009] This process, and the corresponding installation, provides complete satisfaction for the continuous winding of rubber strips to form patties from a rubber sheet continuously extracted from an extruder.

[0010] However, after the sheet is deposited onto the support film, called "liner," made of plastic or textile, the whole is slit into narrow strips of 15 to 50 mm, for example, and then wound into patties approximately 800 mm in diameter.

[0011] This results in several disadvantages, such as the need to handle, cut, and consume liner coils, which will ultimately become waste.

Summary of the Invention

[0012] One of the objectives of the invention is to overcome the aforementioned problems and to provide a continuous winding process and installation for rubber 2 strips, particularly used in tire manufacturing, to form patties from a rubber sheet continuously extracted from an extruder, which is more ergonomic and ecological.

[0013] To this end, a remarkable process has been developed comprising the following steps: - Continuously depositing the sheet exiting the extruder onto a conveyor belt circulating in a closed loop within an accumulator, the accumulator comprising a first zone for accumulating/discharging the conveyor belt alone, and a second zone for discharging/accumulating the conveyor belt receiving the sheet; - Cutting the sheet at its width into a plurality of rubber strips at the exit of the accumulator; - Continuously unwinding support film strip rolls with widths corresponding to those of the rubber strips; - Positioning each rubber strip onto a support film strip and winding them together, at an initial speed, around a support to form rubber patties; - During the formation time of the patties, supplying empty supports intended to receive rubber patties, and supplying full rolls of support film strips, and attaching the support film strips onto the empty supports intended to receive the rubber patties; - When the rubber patties are finished, stopping the winding of the rubber strips and the support film strips, discharging the conveyor belt alone in the first zone of the accumulator, and simultaneously accumulating the conveyor belt receiving the sheet in the second zone of the accumulator; - While the conveyor belt receiving the sheet accumulates, transversely cutting the rubber strips upstream of the rubber patties, and reattaching the rubber strips coming from the extruder to the empty supports; - Simultaneously, finishing the winding of the free end of the rubber strips and the support film strips around the rubber patties, evacuating said rubber patties, and restarting the winding of each of the rubber strips and the support film strips around the empty supports at a speed higher than the initial speed until the conveyor belt receiving the sheet is discharged in the second zone of 3 the accumulator and simultaneously accumulating the conveyor belt alone in the first zone of the accumulator, then resuming the winding at the initial speed.

[0014] This way, the invention allows for the direct and continuous manufacturing of rubber patties from a sheet exiting an extruder. The invention eliminates the need for winding, handling, storing, and unwinding support film coils, making the process more ergonomic. The yield is optimal as the extruder produces a sheet continuously, without stopping, and the rubber strip patties are formed continuously.

[0015] In other words, the invention allows the transfer of the rubber sheet between an extruder and a slitting and winding machine continuously without using a support film during the entire transit phase. The support film is then inserted when rewinding the rubber strips after cutting. The support film is not cut and can be reused, making the process more ecological.

[0016] According to a particular embodiment, the rubber patties are evacuated and replaced by empty supports automatically via a manipulator, making the process of the invention even more ergonomic. These operations are performed in masked time during the winding of the ongoing rubber strip patties.

[0017] Similarly, when the support film strips are transversely cut, the empty rolls of support film strips are automatically evacuated and replaced by new full rolls of support film, preferably via a manipulator. These operations are performed in masked time during the winding of the ongoing rubber strip patties.

[0018] The invention also aims to protect an installation for implementing the described process, comprising successively: - An accumulator with a conveyor belt circulating in a closed loop through which the sheet is intended to pass continuously exiting the extruder, the accumulator comprising a first zone for accumulating/discharging the conveyor belt alone, and a second zone for discharging/accumulating the conveyor belt receiving the sheet; - A cutting module comprising means for cutting the sheet at its width into a plurality of rubber strips; 4

- A winding module for the strips comprising: o Bars for unwinding rolls of support film strips; o A plurality of supports mounted on bars driven in rotation around which the rubber strips positioned on the support film strips are wound together to form the rubber patties; o Sensors detecting that the rubber patties are formed, subjected to evacuation means of the formed rubber patties; o A blade for transversely cutting the rubber strips upstream of the formed rubber patties; o Means for supplying empty supports and winding the cut rubber strips and the support film strips around said empty supports.

[0019] According to the invention, the installation comprises means to subject the rotational speed of the supports to the accumulator so that when the rotation of the supports is stopped or slowed, the conveyor belt alone is discharged in the first zone of the accumulator and the conveyor belt receiving the sheet accumulates simultaneously in the accumulator, and when the winding of the new rubber patties begins, the rotational speed is increased to discharge the conveyor belt receiving the sheet in the second zone of the accumulator and simultaneously accumulate the conveyor belt alone in the first zone of the accumulator, then is slowed to an initial speed.

[0020] Preferably, the installation comprises means for automatic evacuation and supply of rolls of support film strips.

[0021] According to a particular embodiment, the means for supplying empty supports and winding the cut rubber strips and support film strips around said empty supports comprise a rotary flange from which four bars regularly spaced around the flange protrude, the flange being able to be rotated to successively position: - In front of a winding station, a first bar on which the rubber strips positioned on support film strips are intended to be wound; - In front of an unwinding station, a second bar receiving rolls of support film strips;

- In front of a first evacuation/loading station, a third bar on which rolls of rubber strips positioned on support film strips are wound for evacuation and replacement by empty supports; - In front of a second evacuation/loading station, a fourth bar receiving empty supports for evacuation and replacement by rolls of support film strips.

Brief Description of the Drawings

[0022] Other features and advantages of the invention will become clear from the description below, provided as an example and not limited to, with reference to the appended figures in which:

[0023] [Fig. 1] is a perspective view of a continuous winding installation for rubber strips according to the invention.

[0024] [Fig. 2] illustrates in perspective an accumulator with a conveyor belt implemented in the installation, in a resting phase.

[0025] [Fig. 3] is a view similar to that of figure 2, the accumulator being in the phase of accumulating the rubber sheet.

[0026] [Fig. 4] illustrates the exit of the accumulator and the separation of the rubber sheet and the conveyor belt.

[0027] [Fig. 5] is a perspective view illustrating a cutting module for the rubber sheet into a plurality of rubber strips.

[0028] [Fig. 6] is a view similar to that of figure 5, viewed from another angle, and illustrating the means for cutting the sheet into a plurality of rubber strips.

[0029] [Fig. 7] is a perspective view of the winding modules for rubber strips into patties.

[0030] [Fig. 8] is a view similar to that of figure 7, viewed in section along the winding bars of the winding module.

[0031] [Fig. 9] is a detailed view of a winding module, illustrating the transverse cutting means of the rubber strips.

[0032] [Fig. 10] is a view illustrating the means for evacuating the full rubber patties and the empty liner supports. 6

Detailed Description of the Invention

[0033] With reference to figure 1, the invention concerns a process and an installation (1) for the continuous winding of rubber strips (2), particularly used in tire manufacturing. The winding of rubber strips (2) is done around supports, particularly of the sleeve or mandrel type, whose width corresponds to the width of the rubber strip (2), for example from 10 mm to 200 mm. The rubber strips (2) are wound on themselves to form rubber patties (3).

[0034] With reference to figure 1, the invention allows forming patties (3) continuously from a rubber sheet (4) continuously extracted from an extruder (not shown). In practice, an extruder allows the continuous manufacture of a rubber sheet (4) approximately 1600 mm wide.

[0035] With reference to figures 2 and 3, upon exiting the extruder, the rubber sheet (4) is deposited on a conveyor belt (5) circulating in a closed loop within an accumulator (6).

[0036] The accumulator (6) comprises a first zone (6a) for accumulating/discharging the conveyor belt (5) alone, and a second zone (6b) for discharging/accumulating the conveyor belt (5) receiving the sheet (4).

[0037] The first and second zones (6a, 6b) are interdependent. Notably, since the conveyor belt (5) circulates in a closed loop, the accumulation of the conveyor belt (5) in the first zone (6a) leads to the discharge of the conveyor belt (5) in the second zone (6b). By accumulation, it is meant that the length of passage of the conveyor belt (5) and/or the sheet (4) in the corresponding zone is increased. By discharge, it is meant the opposite of accumulation, that is, the length of passage of the conveyor belt (5) and/or the sheet (4) in the corresponding zone is reduced.

[0038] According to figures 2 to 4, the rubber sheet (4) is deposited on the conveyor belt (5) visible in the upper part of the first zone (6a), then the assembly consisting of the sheet (4) and the conveyor belt (5) is directed downwards and passes through an accordion section (6b1) of the second zone (6b), then rises to the upper part where the sheet (4) is separated from the conveyor belt (5) and deposited on motorized transit rollers (7), see figure 4. 7

[0039] The conveyor belt (5) alone returns downward, under the second zone (6b) to pass through an accordion section (6a1) of the first zone (6a) and closes the loop.

[0040] For accumulation or discharge, mobile rollers (8) of the accordion sections (6a1, 6b1) are moved to increase or reduce the length of passage between said rollers.

[0041] With reference to figures 5 and 6, at the exit of the accumulator (6), the rubber sheet (4) alone, deposited on motorized transit rollers, is directed towards a cutting module (9) comprising a plurality of cutting blades (10) arranged to longitudinally cut the rubber sheet (4) at its width to form a plurality of rubber strips (2). The cutting module (9) is well known from the state of the art and will not be described in more detail.

[0042] With reference to figures 7 and 8, at the exit of the cutting module (9), the rubber strips (2) are directed towards a winding module (11) to wind each strip around a support and form rubber patties (3).

[0043] According to the invention, each rubber strip (2) is wound with a support film strip (12), called liner, to form a rubber patty (3). By rubber patties (3), it is meant the winding of rubber strips (2) and liner strips (12).

[0044] Thus, during the unwinding of the rubber strips (2), the liner (12) prevents the strip (2) from sticking and avoids its deterioration.

[0045] In the illustrated embodiment, the installation (1) comprises two winding modules (11) for rubber strips (2), positioned in parallel.

[0046] Each winding module (11) comprises unwinding bars (13, 14) for support film strip rolls (12), and a plurality of supports mounted on bars (15, 16) driven in rotation around which the rubber strips (2) positioned on the support film strips (12) are wound together to form rubber patties (3).

[0047] With reference to figure 9, each module (11) also comprises a transverse cutting blade (17) for the rubber strips (2) upstream of the formed rubber patties (3), and means for supplying empty supports (3a) and winding the cut rubber strips (2) and the support film strips (12) around said empty supports (3a). 8

[0048] The supply of empty supports (3a) can be done manually, but preferably, the means for supplying empty supports (3a) are automatic. The means for supplying and winding the cut rubber strips and support film strips around said empty supports (3a) comprise a rotary flange (18) from which four bars (13, 14, 15, 16) regularly spaced around the flange (18) protrude.

[0049] To be able to, on the one hand, supply empty supports (3a) for winding new rubber patties (3), or full rolls (12a) of liner (12), and on the other hand, evacuate empty liner supports (12b) and full rubber patties (3), the flange (18) can be rotated to successively position the bars (13, 14, 15, 16) as follows: - In front of a winding station (19), a first bar (15) on which rubber strips (2) positioned on support film strips (12) are intended to be wound; - In front of an unwinding station (20), a second bar (13) receiving full rolls (12a) of support film strips (12); - In front of a first evacuation/loading station (21), a third bar (16) on which rolls of rubber strips (2) positioned on support film strips (12) are wound for evacuation and replacement by empty supports (3a); - In front of a second evacuation/loading station (22), a fourth bar (14) receiving empty supports (12b) for evacuation and replacement by rolls (12a) of support film strips (12).

[0050] In practice, motors drive the rotation of the bars (13, 14, 15, 16) in a known manner.

[0051] The empty supports (3a) intended to receive rubber strips (2) are connected to the rubber strips (2) and the support film strips (12) for winding and forming the patties (3). The supports are, for example, fixedly fitted around the bars (13, 14).

[0052] In practice, and with reference to figure 8, the supports on one of the bars (15) are connected to the ends of the rubber strips (2) coming from the extruder and the support film strips (12) coming from the full rolls (12a) of support film strips (12), and are driven in rotation at an initial speed by the bar (15) that supports them.

In this way, winding the rubber strips (2) and support film (12) around the supports forms rubber patties (3). 9

[0053] When the rubber patties (3) are almost formed, meaning they have reached the desired diameter, the flange (18) of the winding module (11) is rotated, for example in the illustrated embodiment, by 180° counterclockwise.

[0054] Thus, for example, when the first bar (15) is full of rubber patties (3) with liner (12), the winding and movement of the strips are stopped, and the accumulator (6) is activated so that the portion of the conveyor belt (5) on which the rubber sheet (4) is deposited accumulates, particularly in the second zone (6b). Simultaneously, the conveyor belt (5) accumulated in the first zone (6a) of the accumulator (6) is discharged. In this way, the extruder remains in operation, and the sheet (4) is continuously produced. In practice, the accumulator (6) can accumulate the rubber sheet (4) for about 1 minute, for example, meaning it can accumulate about 50 meters of sheet (4).

[0055] While the sheet (4) and conveyor belt (5) accumulate in the accumulator (6), the winding module (11) performs a transverse cut of the rubber strips (2) upstream of the patties and automatically attaches the end to said empty supports (3a) of the rubber strips (2) coming from the extruder and, simultaneously, finishes winding the free end of the cut rubber strips (2) and the support film strips (12) around the patties (3), automatically evacuates the formed patties (3), and restarts winding each of the rubber strips (2) and support film strips (12) around the empty supports (3a) at a speed higher than the initial speed until completely discharging the conveyor belt (5) and the rubber sheet (4) in the second zone (6b) of the accumulator (6), and simultaneously accumulating the conveyor belt (5) alone in the first zone (6a), then resumes winding at the initial speed.

[0056] In practice, the support film strips (12) are longer than the rubber strips (2), so by finishing the winding of the strips (2, 12), the rubber strip (2) is protected under several layers of support film strip (12).

[0057] The supply of empty supports (3a) and full rolls (12a) of support film (12) can be performed in masked time while the sheet (4) accumulates in the accumulator. But preferably, the supply is done during the formation time of the rubber patties (3), allowing more time in practice. After supplying full rolls (12a) of support film strips (12), the support film strips (12) are attached to the empty supports (3a) intended to receive the rubber patties (3), particularly during the formation time of the rubber patties (3).

[0058] For the transverse cutting of the rubber strips (2), a pivoting arm (26) with transit rollers (27, 28) for the rubber strips (2) protruding from it is pivoted to position the rubber strips (2) at a cutting system (29).

[0059] Figure 9 shows the pivoted arm (26) and the strips positioned under the mobile blade (17) for the cut. The cut is made with support against a nearby support (30) near one of the transit rollers (28).

[0060] When the rubber strips (2) are cut, the bar (16) supporting the almost formed patties is rotated to finish winding the end of the strips (2, 12) around the patties (3) in combination with a support roller that presses the free end of the strips onto the patties.

[0061] The bar (15) supporting said empty supports (3a) is rotated to start winding the new patties (3).

[0062] Winding the strips around the new supports (3a) is done at a speed higher than the initial speed to completely discharge the accumulator (6) of the conveyor belt (5) with the rubber sheet (4) accumulated in the second zone (6b).

When the second zone (6b) of the accumulator (6) is discharged, and simultaneously the first zone (6a) is accumulated with a portion of the conveyor belt (5), the winding of the strips resumes at the initial speed.

[0063] In parallel, and with reference to figure 10, the formed patties (3) are evacuated, for example by a pusher device (23) that pushes the patties onto a bar (16a) of an evacuation cart (24), and are replaced by empty supports (3a), preferably automatically by a manipulator.

[0064] A pusher device (25) is also installed to push and evacuate the empty liner supports (12b) onto a bar (14a) of the evacuation cart (24), which are replaced by full rolls (12a) of liner (12), preferably automatically by a manipulator.

[0065] In practice, the installation (1) includes sensors that detect when the patties (3) are formed, meaning they have reached the desired diameter. These sensors are subjected to the rotation of the flanges (18) and the rotation of the bars (15, 16) receiving the supports. The rotational speed of the bars (15, 16) is also 11 subjected to the accumulator (6), so when the rotation of the supports (3a) is stopped or slowed, the sheet (4) automatically accumulates in the second zone (6b) of the accumulator (6), and simultaneously the conveyor belt (5) discharges from the first zone (6a), and when winding the new patties begins, the rotational speed of the corresponding bar is accelerated to discharge the accumulated sheet (4) from the second zone (6b) of the accumulator (6) and simultaneously accumulate the conveyor belt (5) in the first zone (6a), then is slowed to the initial speed.

[0066] The installation (1) allows for the automatic winding of rubber strips (2) with support film (12) around supports (3a) to form patties (3) continuously. The extruder does not need to be stopped. The evacuation of the formed patties (3) and the empty liner supports (12b) is preferably automatic, as is the supply of empty supports (3a) for rubber patties (3) and full rolls (12a) of support film (12). The same applies to the operation of cutting the rubber strips to release the patties and attaching the cut rubber strip ends from the extruder to the empty supports (3a) and the support film strips from the full rolls (12a). 12

Claims

EP4330006 PATENT CLAIMS

1. Continuous winding for rubber bands (2), used especially in the manufacture of tires to form rubber patties (3) from a rubber sheet (4) continuously extracted from the extruder, the process comprising the following steps: - Continuous application of the sheet (4) leaving the extruder to the conveyor belt (5) which rotates in a closed circuit inside the battery (6), the battery (6) comprising a first zone (6a) for collecting/unloading the conveyor belt (5) alone, and a second zone (6b) for unloading/stacking the conveyor belt (5) receiving the sheet (4); - Cutting the sheet (4) across its width into several rubber strips (2) at the outlet of the battery (6); - Rolls of support membrane tape (12a) whose widths correspond to the widths of the rubber strips (2) are continuously unrolled; - Place each rubber band (2) on the backing film band (12) and wind them together at initial speed around the support (3a) to form rubber patties (3); - During the formation of steaks (3), supplying empty supports (3a) to receive rubber steaks (3) and supplying rolls (12a) filled with support film strips (12) and attaching support film strips (12) to empty supports (3a) intended to receive rubber steaks (3); - When the rubber patties (3) are ready, stop the winding of the rubber strips (2) and the backing film strips (12), dismantle the transport belt (5) alone in the first zone (6a) of the battery (6) and simultaneously collect the conveyor belt (5) receiving the sheet (4) from the battery (6) for the second zone (6b); - At the same time as the conveyor belt (5) receiving the sheet (4) collects and transversely cuts the rubber bands (2) before the rubber steak (3) and reattaches the rubber bands (2) coming from the extruder to the empty supports (3a); - At the same time, finishing the winding of the free end of the rubber strips (2) and the support film strips (12) around the rubber patties (3), emptying said rubber patties (3), and restarting the winding of each rubber band (2) and the support film strips 12 around the empty supports (3a) at a higher speed than the initial speed, until the conveyor belt (5) receiving the sheet (4) unloads in the second zone (6b) of the battery (6) and at the same time the conveyor belt (5) is collected alone in the first zone (6a) of the battery (6), after which the winding is continued at the original speed. 1

EP4330006

2. The method according to claim 1, characterized in that the rubber patties (3) are emptied and replaced with empty holders (3a) automatically via the manipulator.

3. The method according to claim 1, characterized in that when the support film strips (12) are cut in the transverse direction, the empty rolls (12b) of the support film strips (12) are automatically emptied and replaced with new full rolls (12a) of the support film (12).

4. Installation (1) for a continuously rolling rubber band (2), used in particular in the manufacture of tires, to form rubber patties (3) from a sheet of rubber (4) continuously removed from the extruder, an installation (1) containing in sequence: - Battery (6), with a conveyor belt (5) rotating in a closed loop through which the plate (4) is to pass continuously out of the extruder, an accumulator (6) comprising a first zone (6a) for the batching/unloading of the conveyor belt (5) alone, and a second zone ( 6b) for unloading/stacking the transport belt (5) receiving the sheet (4); - Cutting module (9), comprising means (10) for cutting the plate (4) across its width into several rubber strips (2); - Tape winding module (11), which includes: * Rods (13, 14) for unwinding the rolls (12a) of the backing film tapes (12); + Several supports (3a) mounted on rods (15, 16) which are rotated and around which the rubber bands (2) placed on the support film strips (12) are wrapped together to form rubber patties (3); * The sensors which detect that the rubber patties (3) have been formed are subjected to the evacuation means (23, 24) of the formed rubber patties (3); * Blade (17) for cutting rubber strips (2) transversely before shaped rubber patties (3); + Means for feeding the empty supports (3a) and winding the cut rubber strips (2) and support film strips (12) around said empty supports (3a); the installation (1) comprises the means for aligning the rotation speed of the supports to the charger (6) thus, 2

EP4330006 that when the rotation of the supports (3a) stops or slows down, the transport belt (5) alone is unloaded to the first zone (6a) of the battery (6) and the transport belt (5) receiving the sheet (4) accumulates simultaneously in the accumulator (6), and when the new rubber patties (3 ) winding starts, the rotation speed is increased to unload the conveyor belt (5) receiving the sheet (4) in the second zone (6b) of the battery (6) and at the same time to collect the conveyor belt (5) alone in the first zone (6a) of the battery (6), then slow down to the initial speed.

5. The installation (1) according to claim 4, characterized in that it comprises means (25, 24) for the automatic removal and feeding of the rollers (12a) of the backing film strips (12).

6. Apparatus (1) according to claim 5, characterized in that the means for feeding the empty supports and winding the cut rubber strips and supporting film strips around said empty supports (3a) comprise a rotating flange (18), of which four bars (13, 15, 16) at regular intervals around the flange (18) protrude, so that the flange (18) can be turned one after the other into the position: - In front of the winding station (19), the first bar (15), on which the rubber bands (2) placed on the support film strips (12) are intended to be wrapped; - In front of the winding station (20), a second bar (13) that receives the rolls (12a) of the backing film strips (12); - In front of the first evacuation/loading station (21), the third bar (16) on which the rubber band rolls (2) placed on the supporting film strips (12) are wound, emptying and replacing with empty supports (3a); - In front of the second evacuation/loading station (22), a fourth bar (14) that receives the empty supports (12) for emptying and replacement with rolls (12a) of support film strips (12). 3