Method and device for separating a fabric made of plastic fibers

Abstract

The invention relates to a method and a device for thermally separating a fabric (10) made of plastic fibres (9). According to the invention, an impact pulse acts on the fabric (10), the fabric (10) being arranged in at least one layer between a pair of unheated impact elements (2, 4) such that the fabric separates and forms a separating edge (12), the plastic of the plastic fibres (9) melted during the impact pulse being confined to the region of the separating edge (12).

Description

[0001] The present invention relates to a method and an apparatus for thermally separating fabrics composed of plastic fibers, such as woven fabrics, knitted fabrics, nonwoven fabrics, ropes, cords and threads, all of which are made of meltable synthetic fibers.

[0002] Known methods for processing flat material webs, such as separating films by impact pulses using a film punch according to publication DE 10 2015 211 622 A1, are not suitable for separating fabrics in such a way that a separation edge is formed which protects the fabric or rope from abrasion at the edges after separation.

[0003] Publication JPS58-78605A provides a solution for fabric separation using impact pulses. A continuously generated tear line is divided into sections of desired length by individual impact pulses. However, a continuous, high-speed process is not described.

[0004] The impact device and process according to publication US Pat. No. 4,747,455 A are capable of producing individual impacts, but a continuous process is not described.

[0005] The object of the present invention is therefore to thermally separate textiles based on or consisting of plastic fibers and to provide a reliable, simple and rapid method for continuous use while protecting the textiles from wear. A further object of the present invention is to provide an energy-saving and simple device for separating textiles having the corresponding properties.

[0006] The object of the present invention is achieved by a method for thermally separating textiles based on or consisting of plastic fibers, wherein the plastic fibers must be meltable and have a melting point below the temperature reached during the impact pulse.

[0007] A shock pulse is applied to the fabric, which is arranged in at least one layer between a pair of unheated impact elements, the shock pulse being an impact movement of at least one of the impact elements extending perpendicular to the fabric, wherein the time for at least one of the impact elements to penetrate the fabric is less than 10 milliseconds. When one impact element is working against a base (anvil), a pair of unheated impact elements is also present. The base or anvil then forms the second impact element of the pair. The impact element does not need to be heated. On the contrary, this is quite disadvantageous, especially if heating as an external heat supply leads to softening of the fabric. Therefore, preheating of the fabric is also excluded. Therefore, "unheated" means that the temperature of the impact element and the fabric remains below the softening temperature of the fabric. If the impact element or the fabric is slightly heated for other reasons, this does not affect the method according to the invention, and within the meaning of the present invention, the impact element or the fabric is considered to be unheated or not preheated.

[0008] According to the present invention, opposing impact elements are used in high-speed, continuous processes. The method for thermal separation is preferably integrated into a high-speed, continuous process or a high-speed machine or system. This is particularly suitable for continuous web-guided processes with continuous feed, for example, in systems for producing technical textile products such as face masks. Such systems operate, for example, at 100 cycles per minute.

[0009] The separating edge on a fabric made of plastic fibers, such as a woven, knitted, or nonwoven fabric, or even a rope, cord, or thread, consists of fused plastic fibers. This is produced by or during the thermal separation of the fabric. Thermal separation is defined as follows: the fabric is first compressed or otherwise deformed at a significant point, thereby generating the heat required for separation, and in particular for forming the separating edge, in the fabric. This heat fuses the plastic fibers together.

[0010] For this purpose, a shock pulse is applied to at least one layer of fabric arranged between a pair of unheated impact elements. The effect of the shock pulse occurs between the unheated impact elements. In any case, it is not necessary to heat the impact elements; on the contrary, this would be quite disadvantageous, especially if heating, as an external heat supply, would lead to premature softening of the fabric, thereby reducing the heat generation during forming. Therefore, preheating of the fabric is also excluded. Therefore, in the sense of the present invention, "unheated" means that the temperature of the impact elements and the fabric remains below the softening temperature of the fabric. If, for other reasons, the impact elements or the fabric are slightly heated, this does not affect the method according to the present invention, and the impact elements or the fabric are considered to be unheated or not preheated within the meaning of the present invention. A pair of unheated impact elements is also present if the pair of unheated impact elements is an unequal pair, and one impact element is operated against a base or anvil, which then forms the second impact element of the pair.

[0011] The impact pulse is an impact motion of at least one of the impact elements perpendicular to the fabric layer, wherein the penetration time of at least one of the impact elements into the fabric is less than 10 milliseconds. In this case, the impact pulse, preferably generated mechanically, acts on the fabric, causing it to separate and form a separation edge. This is achieved by directly fusing the separated plastic fibers of the fabric together, as the material reforms with the development of heat during the separation process. This secures the plastic fibers and prevents undesirable unraveling of the fabric from the edge, i.e., wear. The separation edge is formed by the impact pulse penetrating the fabric, deforming it, and thereby briefly heating and melting its fibers, with the heating being limited to the immediate active area, i.e., the region of the separation edge.

[0012] The separating edge can be applied to, for example, woven, knitted, warp-knitted, or nonwoven fabrics, or the fabric can be a rope, thread, or string. Therefore, the plastic melted during the impact pulse is limited to the area directly at the separating edge, whereas conventional melting processes heat and melt a much larger area due to the lack of targeted heating. This results in a larger hardened area and, in some cases, an unsightly appearance.

[0013] The direct confinement of the separating edge to a narrow area is particularly advantageous when the woven, knitted, warp-knitted or nonwoven fabric is cut into finished parts according to the invention and simultaneously edged with the separating edge. By limiting the separating edge to a minimum, there are no hardened areas that could scratch the garment or impair its visual appearance, unlike with conventional melting processes.

[0014] The greater significance of the separating edge and, in this context, its production process lies in the field of technical textiles, such as filter nonwovens or nonwovens for battery production. In large-scale production, shape-based processes are clearly superior to incremental processes such as laser cutting. Additional advantages of the present invention are low energy consumption and simple, fail-safe system technology.

[0015] It has been shown that, in addition to cutting, it is also possible to create embossing in the fabric by means of impact pulses, when the impact element strikes the fabric according to its contour. This effect can be exploited for further applications, such as for curing materials, for imprinting information or for design purposes.

[0016] The surface is solidified using a relatively flat impact element. This can be applied, for example, to wide edges to which other elements are attached (such as the elastic bands on a filtering mask). According to the invention, connections (e.g., to elastic bands) can also be made using the impact pulse, using welding or meltable adhesives. The brief heating required in each case is then also introduced into the material by the impact pulse and the resulting deformation.

[0017] The solidification surface also creates the edge of the eyelet, and the desired opening of the eyelet can be cut beforehand or afterwards. Solidification then occurs similarly to the formation of the separation edge through melting caused by one or more impact pulses. The application of impact pulses can also be performed selectively, in which case multiple solidification points arranged in a row create the desired surface. While linear punches are used for separation with a formed separation edge, relatively flat shapes are advantageous for melting to form the surface or for thermal joining.

[0018] Furthermore, due to the rapid temperature increase, the material temperature has virtually no effect, unless it adversely softens. This also applies to the impact element, which requires no preheating, as the temperature required for bonding is generated within the fabric itself within a very short time during the impulse process. Consequently, heating and melting of the fabric are advantageously limited to the immediate active area and the short contact time. Due to the high deformation speed, adiabatic heating of the fabric occurs in the active area, with minimal energy input and no heat exchange with the surrounding air or adjacent areas of the fabric. Only the amount of plastic fiber material required to form the separation edge by melting the fiber ends together is liquefied. This also prevents liquid material from the molten fibers from being forced out of the joining area and unnecessarily thickening the separation area.

[0019] Preferably, the impact pulse is generated by a mechanical drive. When the impact pulse acts on the fabric, the fabric separates at this point and a compression area and / or a separation edge is formed, followed by a return stroke of the at least one impact element. The impact pulse has at least a first intensity F i1 Acting on the fabric so as to plastically compress the fabric. If the shock pulse has a second intensity F i2 Acting on the fabric, the fabric then separates between the impact elements and, depending on the contour of the impact elements, compressed or at least partially melted separation edges made of melted plastic fibers remain on both sides of the separation line.

[0020] Furthermore, time is saved and energy input is reduced. This narrow heat-affected zone is not achievable with conventional methods for melting fabric edges or ends, as the heat dissipates too quickly, increasing the area of ​​fabric heated and softened. It has been shown that the melting width during separation is limited to no more than twice the thickness of the fabric layer.

[0021] In the step before the impact pulse, the fabric is stretched between a pair of impact elements with a pre-tension force F v The two pieces are pressed against each other. Subsequently, a shock pulse from at least one of the driven impact elements is applied to the fabric, or the shock pulse is transmitted by at least one of the impact elements and ultimately acts on the fabric. Thus, instead of the tool dropping directly onto the fabric, the stacked fabrics are initially pressed together. This partially compensates for the roughness of the tool (and especially the fabric) surfaces. In all cases, a temperature effect occurs in the active area forming the separating edge, leading to localized heating. During the penetration time and due to the mechanical stresses that occur when the shock pulse penetrates at a correspondingly high deformation speed, this causes the plastic of the plastic fiber to melt within a very short time.

[0022] It has proven to be advantageous if, in a step preceding the shock pulse, the fabric is subjected to a pretensioning force F v , preferably by means of at least one pretensioning roller subjecting the fabric to a pretensioning force F v, after which an impact pulse of at least one of the driven impact elements acts on the fabric. In order to carry out the process continuously in this way, the pretensioning device is designed as a rotating pretensioning roller, under which the web can move.

[0023] At least one driven impact element may be movable within the pretensioning roller and execute an impact pulse each time it is aligned perpendicularly to the fabric.

[0024] According to an alternative embodiment, the impact pulse generated by at least one of the driven impact elements is indirectly transmitted to the fabric via at least one pretensioning roller. To this end, the impact pulse is first applied to the at least one pretensioning roller by the at least one impact element. The pretensioning roller is designed to transmit the impact pulse, taking into account that the at least one impact element initially applies the impact pulse to the pretensioning roller. The impact pulse is then indirectly introduced into the fabric via the pretensioning roller. To this end, the pretensioning roller can have a suitable profile on its circumferential surface or a diameter that allows for the application of a shock pulse with an appropriate profile and intensity.

[0025] According to another alternative, the impact drive can also act on the pretensioning roller or on an additional correspondingly profiled roller. In this case, it serves only as an impact element. The additional impact element can then be omitted.

[0026] Melting remains confined to the active area. As a result, surrounding areas are neither affected by undesirable heat input (e.g., burning of the area around the separation edge in the fabric as with conventional melting methods) nor dissipated as energy loss to surrounding areas.

[0027] The impact pulse is preferably generated by a mechanical or magnetic drive, whereby the mechanical drive of the impact element is direct, or the impact pulse is transmitted indirectly via a spring force, a drop weight, a magnetic drive, or a cam drive. The cam drive allows particularly fast movements to be controlled without delay and with precise amplitudes. In particular, the spring force and the drop weight can be manually brought into their force-generating position, allowing the method according to the invention to be performed without an external energy supply.

[0028] If the pair of unheated impact elements is an unequal pair and one impact element rests against a passive, flat base, then there is also a pair of unheated impact elements, with the passive, flat base then forming the second impact element of the pair. The impact pulse is an impact movement of at least one of the impact elements extending substantially perpendicular to the fabric, wherein the time for at least one of the impact elements to penetrate the fabric is less than 10 ms. Preferably, the penetration time is less than 5 ms, particularly preferably less than 1 ms, depending on the thickness of the fabric. To generate the impact pulse, the tool is preferably dropped onto the fabric at a starting speed of 1 m / s to 5 m / s and is braked to a standstill during the penetration time. The impact pulse is preferably generated by a mechanical drive or by an electromagnetic drive.

[0029] The impact pulse is applied via an upper impact element or, as an alternative, via two opposing impact elements. In particular in the case of opposing impact elements, these are used in high-speed, continuous processes or high-speed machines or systems, in particular in continuous web-guided processes with continuous feed, for example in systems for the production of technical textile products such as face masks, which operate, for example, at 100 cycles per minute and are integrated into the system. The impact element can be designed as a roller, which can also serve as a feed roller, for example, which applies the pretensioning force F v , while the pulse force F i The impact on the roller is transmitted to the fabric.

[0030] The object of the present invention is also achieved by a device for separating a fabric composed of plastic fibers by thermal separation. According to the invention, thermal separation is defined as the fabric being initially compressed or otherwise deformed by the penetration-effective area of ​​the impact element, thereby generating the heat required for separation, in particular for forming a separation edge, in the fabric and fusing the plastic fibers together.

[0031] For this purpose, the device comprises a pair of unheated impact elements, between which the fabric is arranged in at least one layer during the separation process; the device for generating pulses introduces impact pulses into at least one of the impact elements during thermal separation, the impact pulses then acting on the fabric, separating the fabric at the separation point and forming separation edges on both sides of the separation point.

[0032] If one impact element is operating against a base (flat anvil), a pair of unheated impact elements is also present, with the base then forming the second impact element of the pair. The pulse generating device is designed to introduce an impact pulse into at least one of the impact elements. The impact pulse is an impact movement of at least one of the impact elements perpendicular to the fabric layer, wherein the impact pulse has a time to penetrate multiple layers of fabric and a time to penetrate a single layer of fabric of less than 10 milliseconds. The impact pulse acts on the fabric and, by melting the plastic fibers at the fabric edge, forms a separating edge in the active area of ​​the impact element. The impact pulse is preferably generated by a drive device.

[0033] According to the invention, the first and / or second impact element is designed to function in a high-speed, continuous process, in particular in a web-guided process with continuous feed, as described above for the method according to the invention.

[0034] According to advantageous embodiments of the method and apparatus, the first and / or second impact elements are designed as rolling tools to function in web-guided processes with continuous feed. Alternatively, the first and / or second impact elements are designed as tools that rotate toward the active point or as tools that temporarily follow the web during the separation or embossing process, as is customary and well-known in web-guided processes for specific process stages, so that the impact pulses can be applied while the web is in motion. The following tools can be composed of additional fixed impact elements, which are, however, guided at the web speed during the impact pulse and then return to their starting position more quickly.

[0035] The device according to the present invention is therefore suitable for installation in complex systems, thereby also replacing existing separation technologies. Advantageously, the pair of impact elements are made of hardened steel with a ground surface. Furthermore, each impact element includes a means for attachment to a drive device.

[0036] According to an advantageous further development, a method for applying a pre-tensioning force F is provided. v A device by means of which, before the impact pulse is applied, the impact element is prestressed by a pretensioning force F v Press against each other.

[0037] In a preferred embodiment, the pair of impact elements includes at least a first impact element having an active area with a profile cross section. It has also proven advantageous if the pair of impact elements includes a second impact element with a wedge-shaped active area. Advantageous profile cross sections have a wedge-shaped profile defined by two radii R2, of any profile shape, and a width a that covers at least the separating edges of the active areas. According to a first alternative, the profile cross section is formed with a radius R1. According to a second alternative, the profile cross section is wedge-shaped, with an angle α relative to the flat active area of ​​the second impact element, and the wedge tip is formed with a radius R3. Generally, regardless of the configuration of the profile cross section (main profile), it is advantageous if it is defined by a radius to prevent undesirable tangling of the fabric at the edges of the profile. It has also proven advantageous if the pair of impact elements includes a second impact element (usually the lower one) with a flat active area or a profile cross section.

[0038] According to a first embodiment, the drive acts on the first impact element, or according to a second embodiment, on both the first and second impact elements. The drive for generating the impact pulse comprises a spring, a drop weight, or a mechanical gear. According to an advantageous embodiment, the mechanical gear is a cam drive, the advantages of which have already been described above. A magnetic drive is also provided that directly drives the impact element or the associated punch.

[0039] Compared with established separation processes, the sealing process proposed by the present invention provides the following advantages:

[0040] Very cost-effective and reliable system and tool technology;

[0041] Possibility of implementing purely mechanical and manually operated solutions (spring pre-tensioning);

[0042] Extremely short process time;

[0043] Specific separation and / or embossing patterns can be achieved by using contour patterns on the tool;

[0044] Very low energy requirements, resulting in very high energy efficiency;

[0045] • It is advantageous as a shape-based process because it is faster than using large volume incremental processes such as laser.

[0046] The above advantages lead to the following favorable application areas:

[0047] Used in continuous processes due to high process speeds;

[0048] For applications where separation is achieved by spring pre-tensioning without electrical energy for mobile use.

[0049] Technical fabrics, such as filter nonwovens and nonwovens for battery production.

[0050] The invention is explained in more detail below based on the description of exemplary embodiments and their illustration in the associated drawings. The drawings show:

[0051] Figure 1 : A schematic diagram of the process sequence of the method for separating fabrics according to the present invention;

[0052] Figure 2 : Schematic perspective views of three embodiments of impact elements having different effective areas according to the present invention;

[0053] Figure 3 : A schematic perspective view of an embodiment of a first percussion element according to the invention having an active region with a flat profile cross section;

[0054] Figure 4 : A schematic perspective view of an embodiment of a second impact element having a flat effective area according to the present invention;

[0055] Figure 5 : Schematic side view of an embodiment of a continuous web guiding process;

[0056] Figure 6 : A schematic side view of another embodiment of a continuous web guiding process;

[0057] Figure 7 : A schematic diagram of an embodiment of a device with separated fabrics according to the present invention;

[0058] Figure 8 : A schematic enlarged view of a separated fabric with a separated edge;

[0059] Figure 9 : A schematic enlarged view of separated plastic fibers of a fabric with separated edges; and

[0060] Figure 10 : Schematic enlargement of the plastic fiber of the fabric with compression-active area.

[0061] Figure 1 A schematic diagram shows an embodiment of the process sequence of the method according to the invention for separating a fabric 10 using impact pulses, which is inserted into the device 1 in two layers. Starting from the left, the process sequence is shown in three steps. First, in the first step, the first impact element 2 is moved along the feed path S. zThe first impact element 2 is moved in the direction of the arrow to the surface of the fabric 10 until the effective contour 6' contacts the fabric 10. The two fabrics 10 to be separated, which should also receive the separation edge 12, rest on the surface of the second impact element 4, which is designed as a flat anvil. The effective contour 6' of the first impact element 2 is wedge-shaped.

[0062] In the second step, the pre-tensioning force F v The first impact element 2 is pressed against the fabric 10. Under the preload thus generated (which compensates for the roughness and elasticity of the fabric 10), in a third step, the impulse force F i Applied to the separating fabric 10 , the fabric 10 melts in the process within a very short time, which also results in the formation of the separating edge 12 .

[0063] As provided by the present invention, when used in a high-speed, continuous process, the described process sequence is repeated in rapid succession.

[0064] Figure 2 Views a), b), and c) schematically illustrate three perspective views of respective embodiments of an impact element 2 according to the invention, each with a different profile cross-section. View a) shows a flat cross-section with a flat working area bounded by two radii R2. In the exemplary effective profile 6, the preferred radius R2 is 1 mm to 4 mm, and the flat profile has a width a of 0.1 mm to 0.5 mm. These and similar, particularly wider, profiles are primarily used for compression.

[0065] In view b), the cross section is wedge-shaped, particularly suitable for separation and forming an effective profile 6, such as Figure 1 In view c), the cross section is designed as a radius and is also suitable for separation, although the separation edge 12 is compressed and is wider overall.

[0066] Figure 3 A perspective view schematically shows an embodiment of a first percussion element 2 according to the invention having an active region 6 with a flat profile cross section, as shown in FIG. Figure 2 The mounting opening 8 is provided for inserting a clamping bolt (not shown here), with which the first impact element 2 is fastened to the impact element holder 26 of the machine (see Figure 5 ), the machine will pre-tension F v and pulse force F i Applied to the first impact element 2 .

[0067] Figure 4A perspective view of an embodiment of a second striking element 4 according to the invention with a flat, anvil-shaped active area is schematically shown.The second striking element 4 is attached to a striking element holder 28.

[0068] Figure 5 A schematic side view of an embodiment of a continuous web guiding process is shown, in which a web 10 is fed from two web rolls 40 and supplied to an apparatus 1 in a double layer. In the apparatus 1 for separating the web 10, the web 10 is fed in a double layer between a first impact element 2 and a second impact element 4, where separation and formation of a separating edge 12 occur (in the illustration, the separating edge 12 has not yet been formed and separation is still to occur). However, precautions must be taken to ensure the continuity of the web guiding process, even during the application of pretensioning forces, in particular during the application of pretensioning forces and impact pulses. This can be achieved, for example, by cyclically moving and returning the apparatus 1 in and against the web guiding direction, or by using a web accumulator after the web rolls 40 and before the apparatus 1 (both not shown, but known from the prior art).

[0069] Figure 6 A schematic side view of another embodiment of a continuous web guiding process is shown. Pretensioning force is applied by pretensioning rollers 42, between which the web 10 is run as two webs. A device 30 for generating pulses, in particular an impact gear, acts on one or both pretensioning rollers 42, so that the web 10 is separated and the separation edge 12 is maintained at the separation point.

[0070] Figure 7 Schematically shown is a side view of an embodiment of a device 1 according to the invention, with simultaneous formation of a separation edge 12 during separation of a fabric 10. Figure 8 The device 1 comprises the impact elements 2 , 4 shown after the return stroke, which release the separated fabric 10 after separation, with the separated fabric 10 having separation edges 12 on the two remaining parts of the fabric 10 .

[0071] Figure 8 A schematic diagram shows an enlarged view of a separated fabric 10 with a separating edge 12. It illustrates how the plastic fibers 9 fuse together, thus forming the separating edge 12. Crucially, this ensures that the fabric 10 remains protected from unwanted wear and tear even after separation, and prevents the individual plastic fibers 9 from detaching. Examples include woven, knitted, or nonwoven fabrics, in which the separating edge can replace the hem. In other examples of the use of the method according to the invention, the fabric is a rope, thread, or string, and the separating edge forms the end that is secured to prevent wear. Without this protection, the plastic fibers 9 can detach from the edge after cutting without further measures, and the fabric 10 gradually unravels.

[0072] Figure 9 Schematically, an enlarged view of plastic fibers 9 belonging to a separated fabric 10 with a separation edge 12 is shown. The heat-affected zone 13 is indicated by a dashed line. This shows that the heat generated in the material by the impact pulse is limited to the separation edge 12.

[0073] Figure 10 A schematic diagram shows an enlarged view of a compression point (compressed area 11 of plastic fibers 9). Textile material 10 is formed from a plurality of plastic fibers 9. The area of ​​plastic fibers 9 adjacent to compressed area 11 does not thicken, as is the case with other thermal separation or welding methods according to the prior art, where liquid plastic material is forced out of the melted area. This clearly indicates that no excess plastic material is melted and displaced.

[0074] In contrast, the heat-affected zone 13 (whose boundary with the unaffected area of ​​the plastic fiber 9 is shown by a dashed line) is limited to the area of ​​the compression connection 14. The plastic fiber 9 and any area outside thereof are not affected by the undesired heating.

[0075] Reference Signs List

[0076] 1 device

[0077] 2 First impact element

[0078] 4 Second impact element

[0079] 6,6' effective range and effective profile

[0080] 8 Mounting opening

[0081] 9 Plastic Fiber

[0082] 10 fabrics, multiple fabrics, fabric materials

[0083] 11 Compression Area

[0084] 12 Separation Edge

[0085] 13 Heat-affected zone

[0086] 20 Impact press

[0087] 22 Stand

[0088] 24 joystick

[0089] 26 First impact element retainer

[0090] 28 Second impact element retainer

[0091] 30 (device for) generating pulses

[0092] 32 Feeding device

[0093] 40 Coil Roll

[0094] 42 Rolling tool, pre-tensioning roller

[0095] a Effective profile width

[0096] R1 First effective contour radius

[0097] R2 Second effective contour radius

[0098] R3 third effective contour radius

[0099] F v Pretension

[0100] F i Pulse force and shock pulse strength

[0101] S z Feed path

Claims

1. A method for thermally separating a fabric (10) consisting of plastic fibers (9), wherein: Impact pulses are applied to a fabric (10) arranged in at least one layer between a pair of unheated impact elements (2, 4), the impact pulses being an impact movement of at least one of the impact elements (2, 4) extending perpendicularly to the fabric (10), wherein the time for at least one of the impact elements (2, 4) to penetrate the fabric (10) is less than 10 ms, whereby the fabric (10) is separated between the impact elements (2, 4) and a separation edge (12) of bonded plastic fibers (9) is formed, characterised in that the opposing impact elements (2, 4) are used for a high-speed, continuous process.

2. The method according to claim 1, wherein The first and / or the second impact element (2, 4) is configured as a rolling tool (42), and the rolling tool (42) is moved in a coil-guided process with continuous feed.

3. The method according to claim 1, wherein The first and / or the second impact element (2, 4) is configured as a tool that pivots towards an effective point and acts in a web guiding process with continuous feed.

4. The method according to claim 1, wherein The first and / or the second impact element (2, 4) is configured as a tool which follows the web during the separation process and functions in a web guiding process with continuous feed.

5. The method according to any one of claims 1 to 4, wherein In a step preceding the shock pulse, the fabric (10) is subjected to a pretensioning force F by means of at least one pretensioning roller (42). v The impact pulse of at least one of the driven impact elements (2, 4) then acts on the fabric (10).

6. The method according to claim 2, wherein: The impact pulse transmitted by at least one of the driven impact elements (2, 4) acts on the fabric (10) via at least one pretensioning roller (42), wherein at least one impact element (2, 4) initially applies the impact pulse to at least one pretensioning roller (42) for transmission to the fabric (10).

7. The method according to any one of claims 1 to 6, wherein The mechanical drive for generating the impact pulse is provided by a spring force, a drop weight, a magnetic drive or a cam plate transmission mechanism.

8. The method according to any one of claims 1 to 7, wherein: The impact pulse is applied by the upper impact element (2) alone or by two opposing impact elements (2, 4).

9. Device for thermally separating a fabric (10) consisting of plastic fibers (9), wherein: The device (1) comprises a pair of unheated impact elements (2, 4), between which the fabric (10) is arranged in at least one layer during the separation process, and further comprises a device (30) for generating pulses, the device (30) being configured to introduce impact pulses into at least one of the impact elements (2, 4); characterised in that the first and / or second impact elements (2, 4) are configured and arranged to function in a high-speed, continuous process.

10. The device according to claim 9, wherein The first and / or the second impact element (2, 4) is configured as a rolling tool (42) according to a first embodiment, as a tool pivoting towards an effective point according to a second embodiment, or as a tool moving with the web during the separation process according to a third embodiment.

11. The device according to claim 9 or 10, wherein: A pre-tensioning device is included, which applies a pre-tensioning force (F v ) and before the shock pulse by means of the pre-tensioning force (F v ) presses the impact elements (2, 4) against each other.

12. The device according to claim 11, wherein The pretensioning device is configured as a pretensioning roller (42).

13. The device according to claim 12, wherein At least one of the impact elements (2, 4) applies the impact pulse to the pretensioning roller (42), and the pretensioning roller (42) is configured to transmit the impact pulse, wherein the impact pulse is introduced into the fabric (10) through the pretensioning roller (42).

14. The device according to any one of claims 9 to 13, wherein The pair of impact elements (2, 4) comprises at least a first impact element (2) having an active area with a profile cross section (6').

15. The device according to claim 14, wherein The profile cross section (6') is designed with a radius R1.

16. The device according to claim 14 or 15, wherein The profile cross section (6') is wedge-shaped and has an angle α relative to the flat effective area of ​​the second impact element (4), and the wedge tip of the profile cross section (6') is designed with a radius R3.

17. The device according to any one of claims 9 to 16, wherein The pair of impact elements (2, 4) comprises a second impact element (4) having a flat active area (6) or having a contoured cross section (6').

18. The device according to any one of claims 9 to 17, wherein The means (30) for generating pulses are configured to act on only one percussion element (2, 4) or on both the first and the second percussion element (2, 4) simultaneously.

19. The device according to any one of claims 9 to 18, wherein The means (30) for generating a pulse comprises a spring, a falling weight or a mechanical gear.

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