Protective device for protecting a movable laydown belt, device for producing a nonwoven fabric, and method for protecting the movable laydown belt

Abstract

The present disclosure relates to a protective device (1) for protecting a movable laydown belt (2) for laying down drawn filaments (3) in order to form a fabric (4), the protective device comprising a belt (5) which can be rolled up on a collecting shaft (6) and which, if necessary, can be laid down on the laydown belt (2) and positioned below a spinneret (7) which extrudes the filaments (3) from a melt so that the melt extruded from the spinneret (7) falls onto the belt (5). The present disclosure further relates to a device for producing a nonwoven fabric (4) having such a protective device (1) and to a method for protecting a movable laydown belt (2) of such a device for producing a nonwoven fabric (4).

Description

[0001] Protective device for protecting a movable conveyor belt, device for producing a non-woven fabric and method for protecting the movable conveyor belt

[0002] The present invention relates to a protective device for protecting a movable depositing belt for depositing stretched filaments to form a nonwoven fabric, a device for producing a nonwoven fabric with such a protective device, and a method for protecting the movable depositing belt of this device for producing a nonwoven fabric.

[0003] In the prior art, devices for the production of nonwoven fabrics are known which operate according to the spunbond process or the meltblown process.

[0004] From DE 102019004969 A1, a device for producing nonwoven fabrics is known, comprising a tool with a spinneret for extruding a plurality of filaments and a lay-up belt designed as a screen belt, onto which the filaments can be laid down to form a nonwoven fabric. The device for producing nonwoven fabrics has a drip guard with a drip tray, which can be moved from a waiting position to a protective position between the spinneret and the screen belt to protect the screen belt. The drip guard thus forms a protective device for the movable lay-up belt. Positioning the drip tray in the protective position is particularly necessary if, for example, due to problems in the extrusion process, no more filaments are extruded, but rather droplets that would reach the screen belt in liquid form.This must be avoided, as such drops will stick to the wire belt and are difficult to remove, potentially only at the cost of damaging the belt. The drip tray, positioned in the protective position, catches any drops in front of the wire belt. It is designed so that the drops can be easily removed. The drip guard is attached to the side of the tool facing the wire belt. The drip tray itself is made of serrated and perforated sheet metal. It is guided in two drip tray guides on opposite sides. The movement of the drip tray from the waiting position to the protective position between the wire belt and the spinneret is achieved by actuators, which are automatically operated by a control unit.

[0005] The known drip guards, especially the drip tray with its associated drip tray guides and actuators, are very complex in design, which entails corresponding costs. Furthermore, when designing the drip guard, it is crucial to ensure that the drip guard, particularly the drip tray guides, does not impede the proper operation of the nonwoven fabric production equipment or any maintenance or conversion work on this equipment. Additionally, such a complex drip guard requires a correspondingly large installation space, specifically a clearance of at least 100 mm above the conveyor belt if the drip guard is not in place.

[0006] The present invention is therefore based on the objective of providing a protective device for protecting a movable depositing belt, a device for producing a non-woven fabric with such a protective device, and a method for protecting the movable depositing belt, which reduce or eliminate the problems of the prior art, in particular reducing the design and control engineering effort.

[0007] This problem is solved by a protective device according to claim 1.

[0008] More precisely, the task is solved by a protective device for protecting a movable depositing belt for depositing stretched filaments to form a nonwoven fabric, which has a belt that can be wound onto a collecting axis and, if necessary, placed on the depositing belt and positioned below a spinneret that extrudes the filaments from a melt, so that the melt extruded from the spinneret falls onto the belt.

[0009] Such a protective device is particularly simple and can be implemented with minimal design effort, especially because the belt is flexible and can therefore perform complex movements without the need for elaborate actuators. For example, after being placed on the discharge conveyor, the belt can be moved along with the conveyor, i.e., moved into the desired position or brought into the desired state. The belt of the protective device is preferably air-permeable, but the openings formed in the belt for this purpose are so small that the melt, which is to be captured by the belt, cannot pass through them. This is possible due to the viscosity difference between the air and the melt.The belt is very thin, so that it can also be arranged below the spinneret if there is a low-height free space above the depositing belt in its depositing area.

[0010] Preferably, the protective device includes a release mechanism. The belt, wound onto the collecting axis, can be unwound towards the discharge conveyor by activating the release mechanism. The release mechanism is designed to unwind the belt from the collecting axis until a specific section of the belt rests on the discharge conveyor, at which point further transport of the belt can occur through contact with the moving discharge conveyor. The release mechanism is preferably activated by an automatically controlled actuator. However, manual activation of the release mechanism would also be conceivable.

[0011] In an advantageous embodiment of the protective device, the belt is connected to the collecting axle at an inner end of the belt when wound up. The belt is connected to the collecting axle by at least one connecting element, e.g., a screw connection. The collecting axle preferably has a hollow cylinder and / or is designed as a hollow cylinder. The belt is then connected to the hollow cylinder.

[0012] Preferably, the release device comprises a spring element, in particular a torsion spring, and a retaining element. The collecting shaft can be locked to the belt in the wound-up state by means of the retaining element. The spring element is pre-tensioned when the belt is wound up. Activating the release device then involves releasing the retaining element. The belt can be unwound towards the discharge belt by means of a rotation of the collecting shaft generated by the spring element. The spring element and the retaining element make the release device particularly easy to design. The retaining element is particularly designed as a brake, which is released by activating the release device. The brake can be released, in particular, by means of an actuator, wherein preferably, in a de-energized state of the actuator, the collecting shaft is locked to the belt in the wound-up state by means of the brake, and the actuator can be energized to release the brake.

[0013] The problem underlying the invention is also solved by a device for producing a non-woven fabric according to claim 5.

[0014] More precisely, the task is then solved by a device for producing a non-woven fabric with a protective device described in advance, with a spinneret for extruding filaments from a melt and with a depositing belt for laying down stretched filaments to form a non-woven fabric.

[0015] Therefore, protecting the movable discharge conveyor in the event of problems during melt extrusion from the spinneret can be implemented with minimal effort in terms of design, control, and / or regulation. In particular, any remaining liquid droplets can be intercepted by the protective device's belt before they reach the discharge conveyor.

[0016] Preferably, the collecting axis of the protective device is arranged in front of the spinneret in the direction of the conveyor belt's placement, specifically in the direction of movement of the conveyor belt within a placement area for the filaments and / or the melt. This ensures that the belt can be transported or conveyed under the spinneret by means of the conveyor belt. The distance between the spinneret and the protective device is sufficient to ensure that the nonwoven production is not disrupted during normal operation of the machine for manufacturing this nonwoven fabric.

[0017] Preferably, the belt is designed to be long enough that, in its unwound state, it extends from the end connected to the collecting axis to beyond the deposit area formed on the discharge belt. In its unwound state, the belt projects beyond the deposit area on the side facing away from the collecting axis with a safety margin of a certain length. This avoids, or at least reduces, the risk of melt extruded from the spinneret, particularly droplets, escaping the unwound belt and reaching the discharge belt. Within or adjacent to the discharge area, the discharge belt and the belt in its unwound state lie parallel to each other. The discharge belt and the belt in its unwound state are in contact with each other within or adjacent to the discharge area, preferably across the entire discharge area. In particular, the belt in its unwound state also makes contact with the discharge belt within the safety margin.

[0018] Preferably, a clearance of 4 mm to 6 mm, and in particular 5 mm, is formed above the lay-up belt in its lay-up area. The height of this clearance corresponds to the distance between the lay-up belt and an adjacent component, which is located first above the lay-up belt, i.e., in the direction of the spinneret, when viewed from the lay-up belt. This first adjacent component can be, besides the spinneret itself, the blowing device for supplying air to the freshly extruded filaments or the walls of a filament duct. Greater clearance heights are also conceivable if the process or the desired nonwoven properties require it.

[0019] Advantageously, a control and / or regulating device is provided, wherein the control and / or regulating device is connected to the protective device, in particular the release device, especially the holding element, via control technology. The control and / or regulating device is configured to detect a malfunction of the device for producing a nonwoven fabric, in particular the spinneret and / or the lay-up belt, and thereafter to trigger the unwinding of the belt, in particular to activate the release device, in particular to release the holding element.

[0020] Malfunctions can include, for example, incorrect temperatures and / or mass flow rates of the melt, particularly in the spinneret. Furthermore, a failure or undesired operating condition of an air supply system for the freshly extruded filaments could be detected as a malfunction. Such air supply systems are located on the side of the spinneret facing the lay-up belt. A failure or undesired operating condition of an extraction system, located on the opposite side of the lay-up belt below the lay-up area, can also be detected as a malfunction. Other process conditions that lead to droplet extrusion are conceivable and can likewise be detected by the control system, thus also causing the belt to unwind.In principle, any undesired combination of parameters of the device for producing a non-woven fabric, which in particular leads to the extrusion of droplets, can be detected as a malfunction. Corresponding sensors of this device are connected to the control and / or regulating unit, so that data acquired by these sensors is available in the control and / or regulating unit.

[0021] The problem underlying the invention is also solved by a method for protecting a movable storage belt according to claim 9.

[0022] More precisely, the problem is solved by a method for protecting a movable depositing belt of a previously described device for producing a non-woven fabric, in which the following steps are preferably carried out in the stated order:

[0023] • Detecting a malfunction of the device for producing a nonwoven fabric, in particular the spinneret and / or the lay-up belt,

[0024] • Unwinding of the belt from the collecting axle,

[0025] • Placing the tape on the discharge conveyor belt,

[0026] • Conveying the belt into the unwound state by means of the discharge belt through contact with the discharge belt, wherein the belt in the unwound state covers the discharge area formed on the discharge belt.

[0027] The release mechanism is preferably activated upon detection of a malfunction, initiating the unwinding of the belt. Specifically, the holding element is then released. Unwinding initially occurs primarily by means of the energy applied to the collecting shaft by the spring element, particularly the torsion spring. After the belt has been placed on the discharge conveyor, further unwinding occurs via the discharge conveyor, with the belt being transported from the conveyor by static friction. Unwinding ends when the discharge conveyor has been braked to a standstill or when the belt has been completely unwound from the collecting shaft. It is conceivable that the discharge conveyor continues to move even after the belt has been completely unwound, resulting in a relative velocity between the belt and the discharge conveyor.The discharge belt is then moved in contact with the belt which is in its unrolled state, resulting in sliding friction between the belt and the discharge belt.

[0028] Preferably, the collecting axis rotates in the opposite direction to the discharge belt, which is then guided around the circumference by means of a discharge belt drive machine having two or more rollers, when the belt is unrolled.

[0029] It can be advantageous if, after detecting a malfunction of the device for producing a non-woven fabric, in particular a malfunction of the spinneret and / or the lay-up belt, the lay-up belt is braked to a standstill, the braking of the lay-up belt being monitored, the unwinding of the belt being triggered and / or the triggering device for unwinding the belt being activated, in particular the holding element being released, if, due to the then current speed of the lay-up belt, the belt is subsequently unwound by contact with the lay-up belt until the belt is in the unwound state and the achievement of the unwound state of the belt essentially coincides in time with the standstill of the lay-up belt.

[0030] This prevents sliding friction between the belt and the discharge belt, and the associated wear on the discharge belt and / or the belt. The discharge belt is preferably decelerated by reducing the speed of a preferably electrically driven motor used to power the discharge belt. Deceleration using a braking device is also conceivable. The speed profiles of the discharge belt during deceleration are generally known and, in particular, stored in the control and / or regulating device. Furthermore, the profiles of the belt's unwind speed from the collecting axis, from the wound-up state to the unwound state, are known and, in particular, stored in the control and / or regulating device.The unwinding of the belt is then triggered, in particular by means of the control and / or regulating device, at a specific time in which the time span until the discharge belt comes to a standstill corresponds to the time span for transferring the belt from its coiled to its uncoiled state.

[0031] Preferred embodiments are described in more detail below with reference to the accompanying figures.

[0032] Fig. 1 schematically shows an embodiment of the device for producing a non-woven fabric with an embodiment of the protective device for protecting a movable conveyor belt in a side view during fault-free operation.

[0033] Fig. 2 schematically shows the embodiment of the device for producing a non-woven fabric with the embodiment of the protective device from Fig. 1 in a side view during the unwinding of a strip of the protective device towards the discharge belt.

[0034] Fig. 3 schematically shows the embodiment of the device for producing a non-woven nonwoven fabric with the embodiment of the protective device from Fig. 1 in a side view during the conveying of the belt into the unwound state by means of the discharge belt.

[0035] Fig. 4 schematically shows the embodiment of the device for producing a non-woven fabric with the embodiment of the protective device from Fig. 1 in a side view with the tape in an unwound state during an extrusion of drops.

[0036] Figures 1 to 4 each show a protective device 1 for protecting a movable depositing belt 2 for depositing stretched filaments 3 to form a nonwoven fabric 4. The protective device 1 includes, among other things, a belt 5 that can be wound onto a collecting axis 6 and, if necessary, placed onto the depositing belt 2 and positioned below a spinneret 7 that extrudes the filaments 3 from a melt, so that the melt extruded from the spinneret 7 falls onto the belt 5.

[0037] This preferably polymeric melt can be supplied by an extruder and fed under pressure to the spinneret 7 via pipelines. The pressurized melt can be forced through the spinneret 7 and thus extruded into the space below the spinneret 7, specifically in the direction of the deposit conveyor 2, towards the filaments 3. The melt exits the spinneret 7 primarily in the direction of gravity. When this document refers to "below" or "above," it refers to the direction of gravity. If problems occur during this process, the melt may still be in liquid form or as droplets at the level of the deposit conveyor 2. To prevent such liquid melt from reaching and contacting the deposit conveyor 2, the conveyor belt 5 can be positioned below the spinneret 7 to protect the deposit conveyor 2. In such a case, the conveyor belt 5 can be positioned between the spinneret 7 and the deposit conveyor 2.

[0038] The protective device 1 has a release mechanism 8. The belt 5 can be unwound from a state Z1, shown in Fig. 1, which is wound up on the collecting axle 6, towards the discharge belt 2 by activating the release mechanism 8.

[0039] The protective device 1 is therefore only required in the event of problems during extrusion, particularly droplet extrusion, in which case the belt 5 is positioned below the spinneret 7. Using the release device 8, the belt 5 can then be unwound towards the discharge belt 2 as needed, namely in the event of the aforementioned problems during extrusion.

[0040] The strip 5 is connected to the collecting shaft 6 at an inner end of the strip 5 in the coiled state Z1. Specifically, the strip 5 is connected to an outer circumference of the collecting shaft 6. The collecting shaft 6 has, in particular, a hollow cylinder and / or is designed as a hollow cylinder to which the strip 5 is connected. Such a hollow cylinder could also have a slot through which the strip 5 is passed, in which case the strip 5 is connected to the hollow cylinder at its inner circumference. The width of the strip 5 and the length of the collecting shaft 6 are matched to each other, with the strip 5 contacting the collecting shaft 6 over its entire width in the coiled state Z1.

[0041] The release device 8 comprises a spring element (not shown), in particular a torsion spring, and a retaining element (not shown). The collecting axle 6 with the belt 5 in the wound-up state Z1 can be locked by means of the retaining element. The spring element is pre-tensioned when the belt 5 is wound up Z1. Activating the release device 8 involves releasing the retaining element, whereby the belt 5, in particular after this release, can be unwound towards the discharge belt 2 by a rotation of the collecting axle 6 generated by the spring element.

[0042] The release device 8, in particular the spring element and / or the retaining element, is arranged, at least partially, within the collecting shaft 6, which then has a hollow cylinder. When the band 5 is wound onto the collecting shaft 6, the spring element can be tensioned to reach the wound state Z1 and is held in this pre-tensioned state by the retaining element. The retaining element locks the collecting shaft 6 by frictional and / or positive locking. The retaining element could be designed as a brake, in which case the collecting shaft 6 can be locked to the retaining element, in particular by frictional locking. The retaining element could also be designed as a pawl, which interacts with a toothed ring formed or arranged on the collecting shaft, in which case the collecting shaft 6 can be locked to the retaining element, in particular by positive locking.

[0043] Figures 1 to 4 each show a device for producing a nonwoven fabric 4 with the previously described protective device 1, a spinneret 7 for extruding filaments 3 from a melt, and a lay-up belt 2 for depositing drawn filaments 3 to form a nonwoven fabric 4. The melt can be supplied, for example, by means of an extruder and fed to the spinneret 7 under pressure, for which a spinneret pump may also be provided. The spinneret 7 has nozzle bores corresponding to the number of filaments 3.

[0044] The collecting axis 6 of the protective device 1 is located upstream of the spinneret 7 in the direction RA of the layup belt 2, i.e., in the direction of movement of the layup belt 2, within a layup area 9 of the layup belt 2 for the filaments 3 and / or the melt. Layup area 9 of the layup belt 2 is the area of ​​the layup belt 2 below the spinneret 7, in which the filaments 3 are laid down onto the layup belt 2 during operation of the device. The layup area 9 does not change its position, even though the layup belt 2 moves in the direction RA and thus the filaments 3 laid down on the layup belt 2 are transported away from layup area 9. An extraction device 12 is arranged on the side of the layup belt 2 opposite the spinneret 7, by means of which air can be extracted through the layup belt 2 in layup area 9 to influence the layup of the filaments 3.

[0045] The belt 5 is designed to be such that, in its unwound state Z2 as shown in Fig. 4, it extends from the end connected to the collecting axle 6 beyond the discharge area 9 formed on the discharge belt 2. In its unwound state Z2, the belt 5 projects beyond the discharge area 9 on the side facing away from the collecting axle 6, with a safety margin 10 of a specific length. Fig. 4 shows that in its unwound state Z2, the belt 5 is completely unwound from the collecting axle 6. Conversely, it is also conceivable that the unwound state is already reached when several layers of the belt are still wrapped around the collecting axle.

[0046] Above the discharge conveyor 2, in its discharge area 9, a clearance with a height H of 4 mm to 6 mm, particularly 5 mm, is formed. Due to the small thickness of the conveyor 5, such a small clearance is sufficient to position the conveyor 5 below the spinneret 7. The clearance is formed, in particular, between the discharge conveyor 2 and an air supply unit connected to the spinneret 7 for supplying air to the freshly extruded filaments 3 and / or the walls of a filament channel for the filaments 3. The clearance is then formed between the end faces of such units facing the discharge conveyor 2 and the discharge conveyor 2 itself.

[0047] A control and / or regulating device 11 is provided, which is connected to the protective device 1, in particular the release device 8, especially the holding element. The control and / or regulating device 11 is designed to detect a malfunction of the device for producing a nonwoven fabric 4, in particular the spinneret 7 and / or the lay-up belt 2, and subsequently trigger the unwinding of the belt 5, in particular by activating the release device 8, in particular by releasing the holding element. The control and / or regulating device 11 is connected to sensors (not shown here) for measuring operating parameters of the device for producing a nonwoven fabric 4 and to actuators for influencing this device. A multitude of malfunctions are conceivable.In particular, the control and / or regulating device 11, which includes a digital processing unit, contains a program that can evaluate the data provided by the actuators and sensors and detect malfunctions based on specific combinations of this data. The combinations that lead to malfunctions are known primarily through experience and are stored in the control and / or regulating device 11.

[0048] By means of the device for producing a non-woven nonwoven fabric 4, a method for protecting the movable depositing belt 2 can be carried out, in which the following steps are preferably carried out in the order mentioned:

[0049] • Detecting a malfunction of the device for producing a nonwoven fabric 4, in particular the spinneret 7 and / or the lay-up belt 2,

[0050] • Unwinding of the belt 5 from the collecting axle 6,

[0051] • Placing tape 5 on conveyor belt 2,

[0052] • Conveying the belt 5 into the unwound state Z2 by means of the discharge belt 2 by contact with the discharge belt 2, wherein the belt 5 in the unwound state Z2 covers the discharge area 9 formed on the discharge belt 2.

[0053] The unwinding of the belt 5 from the collecting axis 6 is preferably effected by means of the spring element. The energy stored in the pre-tensioned spring element is sufficient to lay the belt 5 onto the discharge belt 2 with an area large enough to allow subsequent conveying of the belt 5 by the discharge belt 2. This area is large enough that static friction between the belt 5 and the discharge belt 2 is sufficient for conveying the belt 5. After detecting a malfunction of the device for producing a non-woven fabric 4, in particular a malfunction of the spinneret 7 and / or the discharge belt 2, the discharge belt 2 is braked to a standstill. The braking of the discharge belt 2 is monitored.The unwinding of the belt 5 is triggered and / or the triggering device 8 for unwinding the belt 5 is activated, in particular the holding element is released when, due to the then current speed of the storage belt 2, the belt 5 is subsequently unwound by contact with the storage belt 2, until the belt 5 is in the unwound state Z2 and the reaching of the unwound state Z2 of the belt 5 essentially coincides in time with the standstill of the storage belt 2.

[0054] Conversely, it is also conceivable that the discharge conveyor 2 continues to run even after the conveyor belt 5 has completely unwound from the collecting axis 6, resulting in sliding friction between the conveyor belt 5 and the discharge conveyor 2 until the discharge conveyor 2 comes to a standstill. The discharge conveyor 2 will only come to a standstill when the conveyor belt 5 is positioned below the spinneret 7 in such a way that all extruded melt, especially droplets, falls onto the conveyor belt 5 and not onto the discharge conveyor 2.

[0055] The device for producing nonwoven fabrics 4 is specifically designed for carrying out a spunbond process or a meltblown process. The protective device 1 effectively protects the conveyor belts 2 of this device, thus extending their service life. Additionally, the duration of production downtimes due to problems caused by the protective device 1 can be minimized.

[0056] Reference symbol list

[0057] 1 protective device

[0058] 2. Filing belt

[0059] 3 filaments

[0060] 4 fleece

[0061] Volume 5

[0062] 6 Collector axle

[0063] 7 Spin nozzle

[0064] 8 Triggering device

[0065] 9 Storage area

[0066] 10 Security area

[0067] 11 Control and / or regulatory device

[0068] 12 Extraction system

[0069] Z1 rolled-up state of the band 5

[0070] Z2 unrolled state of the tape 5

[0071] RA Filtration direction

[0072] H Height of a free space above the conveyor belt 2

Claims

Patent claims 1. Protective device (1) for protecting a movable depositing belt (2) for depositing stretched filaments (3) for forming a nonwoven fabric (4), comprising a belt (5) that can be wound onto a collecting axis (6) and, if necessary, laid down on the depositing belt (2) and positioned below a spinneret (7) that extrudes the filaments (3) from a melt, so that the melt extruded from the spinneret (7) falls onto the belt (5).

2. Protective device (1) according to claim 1, characterized in that the protective device (1) has a release device (8), wherein the belt (5) can be unwound from a state (ZT) wound on the collecting axis (6) to the discharge belt (2) by activating the release device (8).

3. Protective device (1) according to claim 1 or 2, characterized in that the band (5) is connected to the collecting axle (6) at an inner end of the band (5) in the rolled-up state (ZI).

4. Protective device (1) according to one of the preceding claims, characterized in that the release device (8) has a spring element, in particular a torsion spring, and a retaining element, wherein the collecting axle (6) with the belt (5) can be locked in the wound-up state (ZI) by means of the retaining element, wherein the spring element is pre-tensioned in the wound-up state (ZI) of the belt (5), wherein activating the release device (8) includes releasing the retaining element, wherein the belt (5) can be unwound towards the discharge belt (2) by means of a rotation of the collecting axle (6) generated by means of the spring element.

5. Device for producing a nonwoven fabric (4) with a protective device (1) according to one of the preceding claims, with a spinneret (7) for extruding filaments (3) from a melt and with a depositing belt (2) for depositing stretched filaments (3) to form a nonwoven fabric (4).

6. Device according to claim 5, characterized in that the collecting axis (6) the protective device (1) in a storage direction (RA) of the storage belt (2) seen, namely in a direction of movement of the depositing belt (2) in a depositing area (9) of the depositing belt (2) for the filaments (3) and / or the melt, is arranged in front of the spinneret (7).

7. Device according to claim 5 or 6, characterized in that the belt (5) is designed to be long such that, in an unwound state (Z2), it extends from the end connected to the collecting axis (6) to beyond the storage area (9) formed on the discharge belt (2), wherein, in the unwound state (Z2), the belt (5) projects beyond the storage area (9) on the side facing away from the collecting axis (6) with a safety area (10) of a certain length and / or that a clearance with a height (H) of 4 mm to 6 mm, in particular 5 mm, is formed above the discharge belt (2) in its storage area (9).

8. Device according to one of claims 5 to 7, characterized in that a control and / or regulating device (11) is provided, wherein the control and / or regulating device (11) is connected to the protective device (1), in particular the release device (8), in particular the holding element, in a control-technical manner, wherein the control and / or regulating device (11) is configured to detect a malfunction of the device for producing a non-woven fabric (4), in particular the spinneret (7) and / or the lay-up belt (2), and thereafter to trigger an unwinding of the belt (5), in particular to activate the release device (8), in particular to release the holding element.

9. Method for protecting a movable depositing belt (2) of a device for producing a non-woven fabric (4) according to any one of claims 5 to 8, in which the following steps are preferably carried out in the order mentioned: • Detecting a malfunction of the device for producing a nonwoven fabric (4), in particular the spinneret (7) and / or the lay-up belt (2), • Unwinding of the belt (5) from the collecting axle (6), • Placing the tape (5) on the discharge tape (2), • Conveying the belt (5) into the unwound state (Z2) by means of the discharge belt (2) by contact with the discharge belt (2), wherein the belt (5) in the unwound state (Z2) covers the discharge area (9) formed on the discharge belt (2).

10. Method according to claim 9, characterized in that after detecting the malfunction of the device for producing a nonwoven fabric (4), in particular a malfunction of the spinneret (7) and / or the discharge belt (2), the discharge belt (2) is braked to a standstill, the braking of the feed belt (2) being monitored, the unwinding of the belt (5) is triggered and / or the release device (8) for unwinding the belt (5) is activated, in particular the holding element is released, if, due to the then current speed of the discharge belt (2), the belt (5) is subsequently unwound by contact with the discharge belt (2) until the belt (5) is in the unwound state (Z2) and the achievement of the unwound state (Z2) of the belt (5) essentially coincides in time with the standstill of the discharge belt (2).

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