METHOD AND DEVICE FOR IMPACTING A FIBER SEMI-FORMET WITH A LIQUID MATRIX SYSTEM

Description

Area of ​​application and state of the art

[0001] The invention relates to a method for impregnating a semi-finished fiber product with a liquid matrix system, as well as a device designed for this purpose. In particular, a textile or a fiber composite or a textile preform made of technical fibers or natural fibers is impregnated and impregnated with a liquid matrix system or with liquid resin, and then cured to form a fiber composite part.

[0002] A fundamentally similar process is known from DE 10 2017 206 999 A1, in which a semi-finished fiber product is impregnated with a liquid matrix system in a flexible and sealable sheath. After the liquid matrix system and the semi-finished fiber product are introduced into the sheath, the sheath is evacuated or suctioned off. The matrix system then expands essentially automatically due to the negative pressure in the sheath and impregnates the semi-finished fiber product. This allows the effort required to impregnate a single semi-finished fiber product to be kept relatively low. At the same time, in some cases, there is a need to be able to carry out the process more precisely and possibly influence it.

[0003] State-of-the-art VARI and VAP vacuum infusion processes utilize a wide range of film materials, membranes, hoses, sealing tapes, and, above all, flow aids. This is known, for example, from EP 1420940 B1 and DE 10013409 C1. Using vacuum films and sealing tapes, vacuum chambers are constructed on molds, into which the semi-finished fiber products to be impregnated are placed. Sprues are fed from reservoirs containing the liquid matrix system within the vacuum chambers via hoses. Flow aids are used to control the impregnation process, allowing the flow resistance to be influenced and ensuring uniform impregnation. Perforated release films and peel plies are used to separate the process aids from one another after the matrix system has cured.

[0004] Another method for impregnating semi-finished fiber products is the so-called prepreg process. Numerous variants are described in the literature. All variants largely have in common that the impregnation of the semi-finished fiber products is carried out openly over resin baths, by spraying and rolling, and then stripping off excess matrix system. These are open and continuous processes. Examples include AU 30864 / 89 A and EP 0363794 A.

[0005] State-of-the-art prepreg systems can only impregnate large fiber quantities in the form of individual rovings and textile web-like semi-finished products such as fabrics, scrims, or tapes. Near-net-shape semi-finished products cannot be processed. Due to the system size and complexity, varying the matrix system is very costly. Customization of the matrix system and small and very small quantities are not possible, or only possible with very high costs.

[0006] US Pat. No. 6,207,002 B1 discloses a method and device for impregnating a semi-finished fiber product with a liquid matrix system or a liquid resin. The semi-finished fiber product is flat and enclosed in a casing. A compression roller runs across the casing to distribute the liquid resin as widely as possible and to press it into the semi-finished fiber product. However, it cannot be guaranteed in every case that the liquid resin is distributed across the entire width of the semi-finished fiber product. Task and solution

[0007] The invention is based on the object of creating a method as mentioned above and a device as mentioned above, with which problems of the prior art can be solved and in particular it is possible to carry out the impregnation of a semi-finished fiber product in a targeted and controllable manner and to optimize it, in particular with regard to the proportion of liquid matrix system in the semi-finished fiber product.

[0008] This object is achieved by a method having the features of claim 1 and by a device having the features of claim 12. Advantageous and preferred embodiments of the invention are the subject of the further claims and are explained in more detail below. Some of the features are described only for the method or only for the device. However, they are intended to be able to apply independently and independently of one another to both the method and a corresponding device. The wording of the claims is incorporated into the description by express reference.

[0009] The semi-finished fiber product is intended to be provided in flat form, advantageously already cut to size, in net shape / near-net shape, or as a textile preform. Alternatively, the semi-finished fiber product impregnated with the liquid matrix system can later be cut and / or generally shaped as required. The semi-finished fiber product is introduced in flat form into a flexible and sealable casing. The casing is advantageously a tube, for example made of film or a film tube, which can be open at one or both ends. It can also consist of two interconnected layers. For flexibility, it can be made thin, thus saving material. The casing can also be adapted to the contour of the textile semi-finished fiber product. It is advantageous to adapt the contour to the semi-finished fiber product. This leads to less loss of matrix system and to more precisely controllable flow behavior of the matrix system.Furthermore, the semi-finished fiber product arranged therein can be processed in this way, and if necessary, advantageous shaping in a press, mold, or the like. Sealing or closing the casing is known per se from the prior art and can be done either by gluing or welding, which is very simple. Alternatively, connections such as suction valves or the like can be arranged or will be arranged. The liquid matrix system is also introduced into the casing. This can take place independently of the introduction of the semi-finished fiber product, so that the order is essentially arbitrary. Advantageously, the liquid matrix system is introduced into the casing separately from the semi-finished fiber product and at a distance from it, wherein a distance can particularly advantageously be between 2 cm and 30 cm or between 5 cm and 15 cm.

[0010] In a next step, pressure is applied continuously and without gaps from above and / or below to the casing, in which the semi-finished fiber product and the liquid matrix system are located, across the entire width of the casing, creating a compression process according to the invention, as described in more detail below. This compression process can begin at one end region of the casing. The compression pressure should be at least 0.1 N / cm² or, if the pressure is applied in stripes or lines, at least 0.5 N / cm based on the length of the compression process. This compression process is carried out continuously, or at least without interruption, along one running direction of the process at least far enough that it extends over the entire length of the semi-finished fiber product. In this way, the entire semi-finished fiber product, including the liquid matrix system, is, so to speak, compressed once.The said running direction extends from a first end region of the casing to a second end region of the casing, whereby this refers to the direction. The compression does not necessarily have to take place from one outermost end at one end region of the casing to the other outermost end opposite. However, it can essentially be done from just before the end to the other end region. In any case, the compression should begin at an area of ​​the casing which is selected such that the liquid matrix system is located between the beginning of the compression and the semi-finished fiber product. This ensures that the liquid matrix system is moved from one end of the semi-finished fiber product in a compressed manner or, with the casing compressed, towards the semi-finished fiber product and over it along the running direction.On the one hand, the liquid matrix system is pressed into the semi-finished fiber product with force or pressure by compression, which assists the impregnation process. On the other hand, any excess liquid matrix system is pressed out of the semi-finished fiber product, so that not too much of it remains, which would be undesirable. Overall, the compression process ensures that a defined or definable amount of liquid matrix system remains in the semi-finished fiber product. This allows the fiber volume content of a finished component to be adjusted as precisely as possible, which is very advantageous for its weight and strength, as well as for the material consumption during its production.

[0011] By compressing the casing, in addition to the semi-finished fiber product possibly partially absorbing the liquid matrix system on its own, the impregnation can be specifically influenced, in particular to ensure that the semi-finished fiber product is impregnated with the liquid matrix system as completely and optimally as possible. One of the main objectives is to influence the content of liquid matrix system in the finished impregnated semi-finished fiber product or the ratio of the two proportions in an impregnated semi-finished fiber product, i.e. the fiber volume content. In particular, it can be achieved that although the semi-finished fiber product is completely impregnated with the liquid matrix system, this may have been at least partially removed again by compression. In this way, the lowest possible proportion of liquid matrix system in the finished impregnated semi-finished fiber product can be achieved.Setting a specific fiber volume content is especially important when using natural fibers for semi-finished fibers. The problem here is that natural fibers can absorb significantly more liquid matrix system or fluid than the aforementioned technical fibers. Some of this must be pressed out again.

[0012] In an embodiment of the invention, it can be provided that a compression pressure across the width of the casing or along the compression, which advantageously takes place perpendicular to the aforementioned running direction, varies by a maximum of 20% of a maximum compression value. Preferably, the compression takes place as uniformly as possible or completely uniformly, so that the proportion of liquid matrix system in the impregnated semi-finished fiber product is as uniform as possible across the width of the compression. At the same time, a compression pressure or, so to speak, a type of height profile can also be adapted to whether a support for the casing on which the compression is carried out, as well as the casing itself, are flat or planar or not. The support on which the casing lies and on which the process is carried out can possibly be profiled orhave a type of depression or indentation through which at least partial shaping of the semi-finished fiber product can take place when impregnated with a liquid matrix system. Providing a type of bed or depression in the support in which the semi-finished fiber product lies at least partially can help to adjust the compression pressure more precisely and precisely. For example, it is possible to manufacture or provide the support at least partially from a so-called shape memory material, in particular a shape memory plastic. In this way, the shape of a depression can be varied to adapt to different conditions. An alternative is a so-called vacuum mattress in the form of a bag filled with bulk material, for example sand or Styrofoam balls. This can be vacuumed or suctioned off and then retains exactly the shape that was specified for it.

[0013] In a corresponding manner, the compression itself could also be carried out with a specific profile, i.e., not consistently straight or flat, but, for example, with a flat support profile. The profile can reflect the opposite thickness distribution of the semi-finished fiber product to ensure constant pressure across the length or homogeneous pressure across the width.

[0014] In an advantageous embodiment of the invention, a negative pressure can be applied to the interior of the casing, in particular to extract air from it. This greatly improves the impregnation of the semi-finished fiber product with the liquid matrix system, as is also known from the aforementioned prior art. A further advantage of applying a negative pressure to the casing is that in the areas outside the semi-finished fiber product, where only the layers of the casing lie on top of one another, these lie firmly and, so to speak, tightly against one another. This prevents any matrix system from penetrating them, and thus the entire matrix system is available for impregnating the semi-finished fiber product. Furthermore, by applying a negative pressure, the position of the semi-finished fiber product in the casing can be fixed, and no further complex aids are required.

[0015] Advantageously, the negative pressure is applied or the air is sucked out at the second end region. Both the liquid matrix system and the semi-finished fiber product should have been introduced into the casing beforehand. At the latest after this and before suction removal, the casing can and should be closed and sealed in this second end region. To introduce the liquid matrix system, it can be provided that an already closed casing is cut open again at one layer, advantageously at an upper layer, over a certain width, for example with a knife or a blade. After the matrix system has been introduced, this cut can be closed again, for example using suitable adhesive tape or the like. A suction connection or the aforementioned suction valve can already be present or can still be attached.At the start of the suction process, the entire casing can be tightly sealed at the second end, including at the first end. For this purpose, it may be advisable to introduce the liquid matrix system into the casing at the first end, which is still at least partially or completely open there, for example if the casing is a long tube with a constant cross-section and open ends before it is closed. The liquid matrix system can be introduced into an area between the first end and the semi-finished fiber product. By introducing the semi-finished fiber product at the opposite second end, the respective processes can be carried out very effectively and, above all, independently of one another. In particular, it is not necessary to reach too far into the casing in each case, which is advantageous both for the semi-finished fiber product and, above all, for the introduction of the liquid matrix system.However, the introduction of both the semi-finished fiber product and the liquid matrix system can be carried out in a manner known per se.

[0016] The liquid matrix system can be introduced into the casing, for example, using an elongated tube or hose that is at least partially inserted into the casing. In an advantageous embodiment of the invention, it is sufficient if the liquid matrix system is applied all at once in one area. This should be done with a width that is less than the width of the semi-finished fiber; however, the width should particularly advantageously be no less than 10% to 30% of the semi-finished fiber. Thus, in a semi-finished fiber that is very wide in the direction of travel, the liquid matrix system can be introduced into at least two areas adjacent to one another, i.e., it can be introduced in a somewhat distributed manner, so to speak.

[0017] In an advantageous embodiment, the compression is not only carried out across the width of the semi-finished fiber product or the casing in a direction perpendicular to the running direction, but is carried out in strips or lines. This ensures that the pressure of the compression affects the entire semi-finished fiber product as well as the entire liquid matrix system. A compression roller is particularly advantageously used for the compression. This can rotate and thus essentially roll over the casing and does not have to drag or be pulled over it. This can help prevent damage. Furthermore, it can be provided that either the casing together with the semi-finished fiber product remains stationary during compression, and the compression or a rotating compression roller is moved over it. Alternatively, the compression can take place in a stationary manner and the casing is pulled through.In particular, a rotating compression roller, such as in a type of press or similar, can pull the wrapping through, possibly comparable to a laundry mangle, in which the liquid matrix system is also to be removed from a textile.

[0018] In the invention, an additional pre-compression takes place in the direction of travel before the compression, i.e., slightly before it. This is also carried out across the entire width of the semi-finished fiber product or the covering. Similar to the compression, the pre-compression also takes place continuously and without gaps. The interval between the pre-compression and the compression can be several centimeters, preferably 2 cm to 10 cm. The pre-compression should therefore precede the compression by this amount.

[0019] The pre-compression can be performed in strips or lines, similar to the compression described above. It should also be at least as wide as the compression, preferably extending at least across the entire wrapper. Furthermore, it should also be performed in a direction perpendicular to the direction of travel or parallel to the compression. A similar device can be provided for the pre-compression as for the compression, possibly including a rotating roller. Alternatively, a simple profile or a simple rod may suffice, and these do not necessarily need to rotate.

[0020] Advantageously, the pre-compression is carried out less forcefully than the compression itself. The primary purpose of the pre-compression is to ensure that the liquid matrix system, which is pushed forward by the compression, does not move too far from the compression point and is then possibly only present in a central region or extends in the direction of travel from the original location of the liquid matrix system's introduction into the casing. Finally, if desired, the semi-finished fiber product should be completely and as evenly as possible saturated with the liquid matrix system across its entire width, so that a sufficient amount of liquid matrix system should always be present or, so to speak, pushed forward before the compression.However, the pre-compression is not intended to force the liquid matrix system into the semi-finished fiber product or to force it back out again in order to remove excess matrix system. Therefore, the pressure for pre-compression can be between 5% and 70% of the pressure for compression. Alternatively or additionally, the distance for pre-compression, for example, between the aforementioned pre-compression roller and a support or the like, can be larger. For example, the distance can be as large as the loose semi-finished fiber product plus the height or thickness of the covering, so that no permanent pressure needs to be applied.

[0021] In a further embodiment of the invention, the compression should be carried out so far across the semi-finished fiber product or the covering that the covering is pressed against the semi-finished fiber product from both opposite sides. This can advantageously be achieved with two opposing compression rollers or by means of a single compression roller and an opposing support on which the covering is located or rests. The same can also apply to the pre-compression.

[0022] In a further development of the invention, the compression and / or pre-compression begin in a region of the casing which also contains the semi-finished fiber product and where there is no liquid matrix system. The liquid matrix system is particularly advantageously located between the two at the start of the pre-compression and the compression, so that the pre-compression begins on one side of the liquid matrix system towards the second end region, and the compression itself begins on the other side of the liquid matrix system towards the first end region. The compression and pre-compression can generally begin at the same time. It is also possible for the pre-compression to begin before the compression in order to avoid the liquid matrix system having already moved too far towards the second end region due to the compression, so that it no longer runs between the two pressures.

[0023] The amount of liquid matrix system that is moved through the casing or across the semi-finished fiber product by compression along the running direction decreases along this running direction. Ultimately, a portion of the liquid matrix system remains in the semi-finished fiber product. However, in the aforementioned embodiment of the invention, it becomes all the more important that the liquid matrix system is distributed across the width of the semi-finished fiber product or the casing by compression, particularly advantageously supported by pre-compression. To prevent the problem of liquid matrix system overflowing too far, which is intended to be avoided by pre-compression, from becoming too great, the distance between compression and pre-compression, measured along the running direction, should not increase during the process. Under certain circumstances, it can even be provided that this distance decreases, for example linearly.Care should be taken to ensure that a distance of at least 1 cm is maintained until the compression has taken place across the semi-finished fiber product and the entire semi-finished fiber product is saturated with the liquid matrix system to the desired extent.

[0024] In general, the stated distance between compression and pre-compression can be a maximum of 20 cm or a maximum of 20% of the length of the semi-finished fiber product in the running direction. It is advantageously between 3 cm and 10 cm or between 3% and 15% of the length of the semi-finished fiber product. In an embodiment of the invention, the distance can be changed or be variable and adapted to the amount of fluid. It can therefore change during the process. Through suitable manipulation, a defined or desired pressure can be set in the liquid reservoir. The distance advantageously decreases as the impregnation or the compression of the semi-finished fiber product progresses, since the amount of liquid matrix system in the liquid reservoir also decreases.

[0025] In a preferred embodiment of the invention, the pre-compression may not occur above the semi-finished fiber product, but rather in front of it or toward the first end region of the sheath. The distance between the pre-compression and the front end of the semi-finished fiber product may be between 1 cm and 10 cm, or only 5 cm, or between 2% and 20%, preferably between 4% and 10%, of the length of the semi-finished fiber product. For the sequence between compression and pre-compression, reference is made to the above explanations.

[0026] In general, the process can be carried out in a continuous run with continuous lateral sealing of two film layers to form a laterally closed wrapping. A very long or even a virtually endless semi-finished fiber product is introduced into this. The supply of matrix system or liquid resin or liquid in general can take place continuously, just as the compression can take place continuously. By means of at least one pressure roller, the wrapping can be closed or sealed towards the front or against a running direction of the process, and the negative pressure according to the invention can be applied in the region thus formed. For this purpose, a line can be introduced into the wrapping from the front. A groove or the like can be used to seal off the aforementioned pressure roller.In a similar way, a line for supplying the matrix system can be routed past the pressure roller and sealed against it. This allows large quantities or a long length of semi-finished fiber, fiber fabric, or fiber composite to be impregnated according to the invention.

[0027] A device according to the invention, with which the aforementioned method can be carried out, has a flat or planar support for the casing. This can be flat or profiled, as described above, in particular recessed or profiled towards the bottom. Further possible designs have been described above. Furthermore, means for introducing the liquid matrix system into the casing are provided, advantageously with an elongated tube or hose. Preferably, the device itself also has means with which the casing can be closed. These are advantageously means for welding the casing if it is made of plastic, for example film. The device has means for extracting air from the casing, advantageously also with a known extraction hose and optionally a valve or check valve introduced into the casing.Means for compressing the wrapping are provided, as described in detail above, in particular in the form of a compression roller. Furthermore, means are provided for generating a relative movement along the running direction between the wrapping and the means for compressing the wrapping. This is advantageously a type of displacement device, but is also known per se from the prior art. For example, the wrapping can be pulled through two oppositely arranged compression rollers, thus generating the aforementioned relative movement. Thus, the support for the wrapping can also be supplemented or replaced by an additional compression roller or a counter-compression roller.

[0028] Overall, the process can also be carried out with a running direction that is not in a horizontal plane, but rather diagonal or possibly even vertical. In this way, the implementation of the process can also be influenced, particularly with regard to the arrangement of the liquid matrix system in an area before compression. For example, it can also be provided that the process begins with an essentially flat running direction and then, only as it progresses, particularly as soon as the liquid matrix system has reached the semi-finished fiber, is the process carried out diagonally or vertically, i.e. the semi-finished fiber is no longer running horizontally, but diagonally or vertically. Due to the adhesive forces, the semi-finished fiber is then, so to speak, fixed in the casing by means of the liquid matrix system and can no longer slip or slide downwards in an undesired manner.For this purpose, the support can be tilted or bent upwards.

[0029] If a compression roller arranged above the covering and a counter-compression roller arranged below are used for compression, a nip is created between them. The covering, possibly with the semi-finished fiber product inside it, runs within this nip. The nip or distance can be adjusted so that at a given point it is as large as the thickness of the semi-finished fiber product when it is saturated with the desired amount of liquid matrix system or when a portion of the liquid matrix system has been pressed out again. The thickness of the covering is also added to this.

[0030] The rollers can be made of either relatively hard or non-compliant materials, such as hard plastic or steel. Alternatively, they can be made of elastic materials such as rubber, foamed materials, or similar, in certain areas or over their entire surface. This can apply to a compressed roller or its counter-compressed roller, or alternatively or additionally to a pre-compression profile or a counter-pre-compression profile.

[0031] The pre-compression can be performed from above onto the casing using a pre-compression profile or similar. Either the aforementioned flat or planar support for the casing can be used as a counter-support, or alternatively, a counter pre-compression profile arranged below the casing. However, as explained above, these can be of relatively simple design and do not need to be movable relative to one another or driven to rotate or even rotate at all.

[0032] The process according to the invention can also be used for higher-viscosity matrix systems / liquids, particularly when implemented with the application of negative pressure. Viscosities of approximately 350 mPas (at room temperature) are typical for such processes for impregnating a semi-finished fiber product with a liquid matrix system, also known as VARI processes. A process according to the invention allows the use of matrix systems with a viscosity of up to 1100 mPas (at room temperature). This makes the use of significantly higher-viscosity matrix systems possible.

[0033] These and other features emerge not only from the claims but also from the description and the drawings. The individual features may be implemented individually or in combination in one embodiment of the invention and in other fields, and may represent advantageous and protectable embodiments for which protection is claimed here. The division of the application into individual sections and subheadings does not limit the generality of the statements made therein. Brief description of the drawings

[0034] Embodiments of the invention are illustrated schematically in the drawings and explained in more detail below. The drawings show: Fig. 1 a side view of a device according to the invention for carrying out the method, wherein a hose as a covering is still open at the end regions, Fig. 2 the device from Fig. 1 after the process has begun, in which part of a semi-finished fibre product in the hose has already been impregnated with a liquid matrix system, Fig. 3 an oblique view of a slightly differently designed device with compression from above and below, Fig. 4 an enlarged detailed view of Fig. 3 in the area of ​​compression and Fig. 5 a right end section of the hose with suction valve and suction hose as well as flow aid, Figs. 6 and 7 a modification of a device according to the invention with a differently designed profile for pre-compression at the beginning of the process and at the end of the process, Figs. 8 and 9 a further modification of a device according to the invention with a displacement body in the bubble of matrix system at the beginning of the process and at the end of the process, Fig. 10 a further modification of a method according to the invention with rolling up the hose at the end for compression, Fig. 11 a further modification of a method according to the invention with increasingly oblique guidance of the hose, Fig. 12 a modification of a method according to the invention according to Fig. 11 with vertical hose routing, Fig. 13 a side view of an apparatus according to the invention for continuously carrying out the method and Fig. 14 a top view of the device Fig. 13 . Detailed description of the implementation examples

[0035] In the Fig. 1 a device 11 according to the invention is shown in side view, with which the method according to the invention can be carried out, as will be apparent from the synopsis of the Fig. 1 and 2becomes clear. The device 11 has a support 12, which can be flat and planar, here as the top side of a work table 13 or the like. A tube 30, which consists of an upper layer 31 and a lower layer 32, is placed on this support 12. The two layers 31 and 32 are closed on the long sides, while a left-hand first end region 34 and a right-hand second end region 35 are open, thus forming the aforementioned wrapping. The tube 30 is advantageously made of thin plastic film, for example a composite film with PE / polyamide. It can be produced by folding it over and welding it along one long side. It is advantageously essentially transparent in order to be able to better observe and monitor the processes taking place therein. So-called air flow aids can be introduced into the film by local embossing, so that the embossing protrudes slightly inwards on the inside of the tube 30.Thus, thin air channels are formed when the two layers 31 and 32 of the hose 30 lie on top of each other, making complete air extraction easier and more effective. The liquid matrix system or a corresponding liquid resin, etc., cannot flow through these thin air channels.

[0036] The hose 30 can be a finished hose, open only at the ends. Alternatively, two separate films, or the lower layer 32 and the upper layer 31, can be placed on top of each other and welded together lengthwise, which is easily done. After the lower layer 32 is placed on the support 12, a semi-finished fiber product can be placed on top, onto which the upper layer 31 is then placed. This is then welded, making it very easy to insert the semi-finished fiber product into the thus formed hose 30.

[0037] In the second end region 35, in the upper layer 31, a suction valve 36 is attached, designed as a one-way valve or a check valve. Furthermore, the suction valve 36 can also contain a membrane and thus be semi-permeable, whereby the membrane prevents air from flowing back into the tube 30. This allows air to be suctioned through the suction valve 36, but not the liquid matrix system. This membrane can thus be impermeable to the liquid matrix system. This can prevent contamination of a suction pump. By means of a suction hose 37 leading from it, air can be suctioned from the interior of the tube 30. The suction valve 36 then closes automatically and automatically, so that a permanent negative pressure does not necessarily have to be applied. On the one hand, it is possible to provide a single suction valve 36. On the other hand, multiple suction valves can be provided or suction can take place at multiple points.

[0038] In the Fig. 1With the upper layer 31 and lower layer 32 spaced far apart, it can be seen how a flat and planar semi-finished fiber product 40 is inserted, for example made of glass fibers, alternatively of carbon fibers or natural fibers such as flax, hemp, sisal or kenaf. The semi-finished fiber product can also consist of several separate or individual layers of fibers. After impregnation with the liquid matrix system, these can either remain on top of each other and together form a component. Alternatively, they can also be separated from each other and further processed separately. When using the aforementioned natural fibers, it should be noted that they are partially hollow and can therefore also absorb additional matrix system or liquid resin or the like in a hollow space. However, this increases the overall proportion of matrix system, which is viewed as a negative.With such natural fibers, it can be particularly advantageous to squeeze out some of the liquid by applying additional pressure.

[0039] It can be seen that the semi-finished fiber product 40 is only approximately half as long in the running direction L for the subsequent process as the hose 30 as the sheathing according to the invention, or is significantly shorter. In fact, the hose 30 projects 20 cm beyond the semi-finished fiber product 40 on both sides. The running direction L runs from the left first end region 34 to the right second end region 35. The semi-finished fiber product 40 can be woven, laid, braided, or the like. Below its right end region is a strip of a flow aid 42 of a known design, which should extend a few centimeters below the semi-finished fiber product 40. At the same time, it should also extend a few centimeters beyond it to the right in the running direction L. The flow aid 42 can advantageously extend as far as the suction valve 36.

[0040] To the left of, or in front of, the semi-finished fiber product 40 in the direction of travel L is a certain amount of liquid matrix system 45, which can advantageously be a liquid resin or another liquid impregnating agent with which the semi-finished fiber product 40 can be turned into a solid component. The liquid matrix system 45 is introduced in a predetermined amount from the left through the open first end region 34 using an introduction tube 16. It is already provided with a hardener, although heat can also be used to activate it. Any system can be used as the liquid matrix system and as the hardener, possibly even tailored to the specific material of the semi-finished fiber product 40. This is irrelevant for the process itself.To introduce the liquid matrix system 45 into the hose 30, the introduction tube 16 is guided from the left through the open first end region 34, then the liquid matrix system 45 is dispensed, and finally the introduction tube 16 is pulled out again to the left. It can be seen that the introduced quantity of liquid matrix system 45 is a considerable distance from the left end of the semi-finished fiber product 40. This distance can be, for example, 5 cm to 20 cm. In practice, at the latest after the introduction tube 16 has been pulled out, the upper layer 31 of the hose 30 will lie on the lower layer 32, i.e., on the liquid matrix system 45 and the semi-finished fiber product 40 as well as the flow aid 42. This will of course become even more pronounced as soon as the air is sucked out of the hose 30.

[0041] The semi-finished fiber product 40 is introduced either before or after the introduction of the liquid matrix system 45 into the tube 30, possibly even simultaneously. This can advantageously be done from the right through the second end region 35, which is open to the right, either manually or with a suitable machine or robot. The flow aid 42 is advantageously introduced after or before this, pushed slightly under the right end of the semi-finished fiber product 40. Alternatively, the flow aid 42 could be placed on the right end of the semi-finished fiber product 40, which would be easier to implement.

[0042] In the next step, a first cut-and-weld tool 18 is pressed onto the hose 30 from above in the left end region 34, moving in the direction indicated by the vertical arrow. The first cut-and-weld tool 18 presses the upper layer 31 of the hose 30 against the lower layer 32, and these two are then heat-welded. A protruding end of the hose 30 may also be cut off. This seals the first end region 34 in an airtight and liquid-tight manner.

[0043] A similar procedure is followed in the right-hand second end region 35, although this can be done simultaneously or one end region at a time. Here, a second cut-and-weld device 19 is brought in from above, which seals the hose 30 as a liquid-tight and airtight covering in the second end region 35 as well. Thus, the entire hose 30, including the semi-finished fiber product 40, flow aid 42, and liquid matrix system 45, is sealed within it.

[0044] Since, as expected, there is still air in the tube 30, this air is sucked out by means of the suction hose 37 through the suction valve 36, advantageously using a connected vacuum pump. Due to the pressure that consequently acts from above on the tube 30 and thus primarily on the bladder 46 containing the liquid matrix system 45 between the layers 31 and 32, the liquid matrix system 45 will spread out over a large area. However, since this spreading out over a large area is intended to be particularly well controlled with the invention, a compression roller 23 and a pre-compression profile 26 are simultaneously lowered from above, as shown by the vertical arrows. They press, so to speak, from above on the tube 30 and its contents. A pressure or compression Z on the compression roller 23 can be as large as explained above, for example at least 0.1 N / cm 2< or at least 0.5 N / cm 2< and up to 10 N / cm 2<.In relation to the length, this can be a pressure of 0.1 N / cm up to 10 N / cm for a length of the compression roller 23 between 0.5 m and 1 m. As an alternative to setting a specific pressure, it is possible to operate at a specific geometric value, for example, a distance of 1 mm to 10 mm between the compression roller 23 and the support 12 can be set. This can also be adapted to the respective properties of the semi-finished fiber product 40 and the liquid matrix system 45. Through this set or resulting compression pressure Z, which is determined based on the . Fig. 2 As is easy to imagine, it is also ensured that the liquid matrix system 45 can under no circumstances reach the left of the compression roller 23 or in front of the compression roller 23, contrary to the running direction L.

[0045] The pre-compression profile 26 is also moved downward, but presses significantly less forcefully on the hose 30 or downwards. A pressure or pre-compression V can, for example, be 5% to 70% of the compression pressure Z by the compression roller 23. Thus, the pre-compression profile 26 can press downwards with a force of only 0.01 N / cm to 1 N / cm over a length between 0.5 m and 1 m. For example, it can also simply rest on the hose 30 due to its weight or have a constant gap.

[0046] As soon as the compression roller 23 presses down and compresses the tube 30 and its contents, and the pre-compression profile 26 has also moved down, the compression roller 23 and the pre-compression profile 26 are moved together, advantageously at a constant distance, along the running direction L over the tube 30 and its contents. Alternatively, they could also remain stationary, while the work table 13 underneath is moved counter to the running direction L. The relative movement between the two is important. Then the compression roller 23 and the pre-compression profile 26, as the Fig. 2As is easily recognizable, the forming bubble 46 with the liquid matrix system 45 within it moves forward across the entire width of the semi-finished fiber product 40 and the tube 30. This is only possible when a negative pressure is applied. Across this width, the bubble 46, as a liquid reservoir, is approximately the same size, so that a constant impregnation of the semi-finished fiber product 40 by means of the liquid matrix system 45 occurs from above. This impregnation of the semi-finished fiber product 40 is greatly assisted by the fact that the compression roller 23 presses the liquid matrix system 45, so to speak, from top to bottom into the semi-finished fiber product 40.

[0047] By varying or adjusting the pressure of the compression roller 23 in the thickness direction, which should advantageously remain constant throughout the entire process, not only can the matrix system 45 be pressed into the semi-finished fiber product 40, so to speak, thereby ensuring the best possible impregnation. Furthermore, as explained at the beginning, the compression roller 23 can also, similar to a mangle, press the liquid matrix system 45 out of the saturated semi-finished fiber product 40 and, so to speak, push it forward as part of the bubble 46. This ensures that the semi-finished fiber product 40 is not saturated with too much matrix system 45, so that the fiber content is as high as possible. This saves a quantity of matrix system 45 and improves the strength or other desired material properties of a finished fiber-reinforced component. The aforementioned pressure for compression Z can then also be set accordingly higher.The applied negative pressure and, above all, the pressure from the compression roller 23 ensure that no more liquid matrix system 45 can subsequently enter the semi-finished fiber product 40 to the left of or in front of the compression roller 23.

[0048] The process is carried out until the compression roller 23 has pushed or distributed the liquid matrix system 45, present in the form of the bubble 46, once over the entire semi-finished fiber product 40 along the running direction L. For special applications, the process may also be terminated earlier, so that a portion of the semi-finished fiber product toward the right-hand second end region 35 of the tube 30 is not impregnated with the liquid matrix system 45. However, this will remain a special case.

[0049] In contrast to the aforementioned flat and level upper side of the support 12 of the work table 13, this support can also have a certain profiling. This can serve to vary the counterpressure created by the support 12 in the case of a round-cylindrical and straight compression roller 23, and thus also to vary the overall compression Z. In this way, it can be achieved that, drawn across the width, some width areas of the semi-finished fiber product 40 are impregnated with more and some width areas with less liquid matrix system 45. Instead of profiling the upper side of the support, the compression roller 23 and / or the pre-compression profile 26 can also be profiled. They can, for example, have a reduced diameter in the area in which the semi-finished fiber product 40 is moved over. This is particularly true when the pre-compression profile 26 is not rotating orIf it does not rotate, it can also be bent slightly upwards so that it extends further above the semi-finished fiber product 40 than in an adjacent area. Thus, it can be provided that any residual liquid matrix system after impregnation is minimized, in particular less than 10% or less than 5% of the originally introduced amount.

[0050] Furthermore, it can be provided that the entire process is not carried out horizontally. For example, the work table 13 or the support 12 could be tilted as soon as the liquid matrix system 45 reaches the semi-finished fiber product 40 or has been pressed against it by the compression roller 23. For example, the right-hand second end region 35 can be raised or lowered relative to the left-hand first end region 34, thereby influencing the spread of the liquid matrix system 45 in the semi-finished fiber product 40. Lateral tilting is also possible, with a similar effect on the spread of the liquid matrix system 45 in the semi-finished fiber product 40.

[0051] In an alternatively designed device 111, in which the same hose 30 as in the Fig. 1 and 2with semi-finished fiber product 40, flow aid 42, and liquid matrix system 45 therein, an upper compression roller 123 and a precisely opposite lower counter-compression roller 124 are provided. They are advantageously identical and have an adjustable distance from each other. This can serve, according to the step of Fig. 1 to Fig. 2 to begin the compression Z of the tube 30 and its contents. Alternatively, the tube 30, closed at the end regions 34 and 35, and its contents therein, can be guided with the end region 34 toward stationary compression rollers 123 and 124. These compression rollers 123 and 124 can then rotate, thus pulling the tube 30 through, similar to a mangle, thereby effecting the compression Z according to the invention.

[0052] In the running direction L, slightly in front of the compression rollers 123 and 124, an upper pre-compression roller 126 and a lower counter-pre-compression roller 127, which acts as a counter roller, are provided. The distance can be similar to that shown in the Fig. 1 and 2 . The mobility of the pre-compression rollers 126 and 127 should also correspond to that of the compression rollers 123 and 124. Therefore, the compression Z and also the pre-compression V are not carried out against a support corresponding to Fig. 1exerted, but against correspondingly designed counter-rollers. This also allows a better or more precise adjustment of the distance between the rollers, in particular a so-called nip between the upper compression roller 123 and the lower compression roller 124, i.e. their distance from one another. This may allow an even more precise adjustment of the content of liquid matrix system 45 in the subsequently soaked or impregnated semi-finished fiber product 40, i.e. the fiber volume content. Furthermore, a structural design may be simpler, especially in the manner of a mangle. It is not necessary to provide that according to the Fig. 1 and 2 the compression roller 23 together with the pre-compression profile 26 can be moved along the running direction L over the tube 30 together with its contents.

[0053] In the enlarged side view of the Fig. 4It can be seen how a quantity or bubble 46 of liquid matrix system 45 is present both on the top side of the semi-finished fiber product 40 and on its underside between the upper layer 31 and the lower layer 32 of the tube 30. This enables, especially with somewhat thicker semi-finished fiber products 40, a precisely uniform and similar saturation of the semi-finished fiber product 40 with liquid matrix system 45, namely from above as well as from below. The saturation then also takes place through the entire semi-finished fiber product 40. In the design of the Fig. 2 The liquid matrix system is located, so to speak, only on the upper side of the semi-finished fiber product 40. In a corresponding manner, as previously described, a distance between the pre-compression rollers 126 and 127 can also be adjusted, but preferably it remains the same. Fig. 4As is also clearly shown, their distance from one another is greater than that of the compression rollers 123 and 124. In particular, a clear width or a so-called nip between them amounts to the height of the loose, unloaded semi-finished fiber product 40 together with the two layers 31 and 32 of the tube 30. This can possibly also be the height of the semi-finished fiber product 40 that is achieved when the tube 30 has been vacuumed off using a provided negative pressure. This may result in the height of the loose semi-finished fiber product 40 being reduced somewhat again. Then, under certain circumstances, it may happen that a small portion of the matrix system 45 reaches, so to speak, in front of the pre-compression rollers 126 and 127 in the running direction L. However, in doing so, it will essentially already saturate the semi-finished fiber product 40, which is overall desired, so that this is not necessarily to be regarded as a negative.However, an excessive amount of matrix system 45 should not reach the pre-compression rollers 126 and 127, since then there may be too little matrix system 45 across the width of the compression to be pressed into the semi-finished fiber product 40 by the compression rollers 123 and 124.

[0054] In the Fig. 5 It also shows how the right end of the semi-finished fiber product 40 slightly overlaps the flow aid 42. Here, the flow aid 42 extends below the suction valve 36. This shows a state without strong suction by means of the suction hose 37, since otherwise the two layers 31 and 32 of the hose 30 would lie much more closely against the semi-finished fiber product 40 and the flow aid 42. Furthermore, the closed right second end region 35 can also be seen here.

[0055] In practice, a vacuum of approximately 400 mbar to 20 mbar can generally be used or applied, preferably 300 mbar to 40 mbar. This can be achieved without too much effort and ensures sufficient suction of air from hose 30. The vacuum should ideally be maintained permanently. If this is not possible with the aforementioned one-way valve alone, a vacuum pump used for suction should be operated repeatedly or even continuously.

[0056] In the Fig. 6 is based on the representation of the Fig. 4shown how the process is carried out with an upper compression roller 223 and a lower compression roller 224, which are unchanged. A hose 30 with a semi-finished fiber product 40 therein is processed. In the running direction L, just before the rollers 223 and 224, there is a bladder 246 with a matrix system 245 therein. This is the case above and below the hose 30 and the semi-finished fiber product 40, respectively. Here, an upper pre-compression profile 226 and a lower pre-compression profile 227 are tapered towards the rollers 223 and 224. With the large distance between them according to Fig. 6 This does not yet play a role. In advanced procedures according to Fig. 7It can be seen that shortly before reaching the end of the semi-finished fiber product 40 in the tube 30, the distance is very small. The left-pointing tip of the upper pre-compression profile 226 has moved almost up to the upper compression roller 223. The same applies below for the lower pre-compression profile 227 and the lower compression roller 224. Thus, the possible space for a bubble of the matrix system 245 is greatly reduced or almost completely disappears. Since the right end of the semi-finished fiber product 40 has almost been reached and the impregnation is almost complete, the consumption of liquid matrix system 45 can be optimized. For example, with a very small bubble, the remaining matrix system 245 is located directly in front of the gap between the two rollers 223 and 224.

[0057] In the Fig. 8is shown with a support 312, how a displacement body 348 inserted in a bubble 346 of matrix system 345 can be used. The bubble 346 is formed between a compression roller 323 and a pre-compression roller 326 similar to the Fig. 2 The displacement body 348 can, for example, be a tube or a balloon, filled with air, and be elastic. If the bubble 346 is still relatively large because the distance between the compression roller 323 and the pre-compression roller 326 is still relatively large and the impregnation of the semi-finished fiber product 40 has just begun, the displacement body 348 is also somewhat larger. Fig. 9When the end of the semi-finished fiber product 40 is reached, it is shown that the distance between the compression roller 323 and the pre-compression roller 326 has been significantly reduced. As a result, the bubble 346 has essentially disappeared, and the displacement body 348 is also significantly compressed. However, it can still easily fill the space between the compression roller 323 and the pre-compression roller 326, since the matrix system 345 has been pressed into the semi-finished fiber product 40 or has been sufficiently saturated.

[0058] In the Fig. 10For a further variant, it is shown that the pressure can be exerted not only by moving a roller 423 similar to rolling it over a semi-finished fiber product 40 arranged on a support 412 in a hose 30, wherein the hose 30 contains a liquid matrix system 445. Here, the hose 30 is wound onto the roller 423, which rotates clockwise and is moved to the right along the running direction L of the process over the support 412. In this way, not only a short-term linear pressure is exerted on the hose 30 and the semi-finished fiber product 40 therein, including the matrix system 445, but also a permanent pressure when wound up. For winding up, it is advantageous if, as is usual, a pre-compression profile 426 is located slightly in front of the roller 423, so that a bubble 446 of the matrix system 445 is formed in the hose 30 between the two.Here, too, air is advantageously sucked out of the hose 30 via a drain valve 436, thus creating a negative pressure therein.

[0059] Another advantage of winding onto the roller 423 may be that the finished impregnated semi-finished fiber product can be transported and delivered immediately, or alternatively, stored. Alternatively, the tube 30 with the impregnated semi-finished fiber product 40 inside can be unwound, and the semi-finished fiber product 40 can be removed from the tube 30 and further processed.

[0060] In the Fig. 11shows how the method can be carried out with an upper compression roller 523 and a lower compression roller 524 without a pre-compression profile or roller. For this purpose, a curve along which the two compression rollers 523 and 524 are moved or along which a hose 30 or a casing 539 formed thereby with a semi-finished fiber product 40 and liquid matrix system 545 is guided therein is bent continuously upwards from horizontal along the running direction L. Here, the running direction L therefore forms a curve and is not straight as in the previous exemplary embodiments. Due to gravity alone, a bubble 546 of the liquid matrix system 545 forms in front of the upper compression roller 523. Such a bubble could also be formed in the hose 30 below the semi-finished fiber product 40.

[0061] In yet another embodiment of the Fig. 12the running direction L runs vertically upwards, either as the final phase of the process Fig. 11 or exclusively and vertically upwards from the beginning. Here, a left compression roller 623 and a right compression roller 624 are provided, between which a hose 30 with a semi-finished fiber product 40 is located. On both sides of the semi-finished fiber product 40, above the compression rollers 623 and 624 and practically adjacent to them, a bubble 646 with a liquid matrix system or liquid resin is formed. This allows for even impregnation of the semi-finished fiber product 40 from both sides, which can be advantageous, for example, with particularly thick semi-finished fiber product 40. Here too, and in the Fig. 11 Again, what is not shown is that a negative pressure should be applied to the hose 30 or air should be sucked out as previously described.

[0062] In the Fig. 13 is in side view and in the Fig. 14A further embodiment of a device 711 is shown from above, with which a semi-finished fiber product 740 as a fiber composite or non-woven fabric can be soaked or impregnated with a liquid resin 745 as a matrix system. The special feature here is that, as described above, the semi-finished fiber product 740 is soaked with the liquid resin 745 over a long length or, so to speak, endlessly in a continuous process. The semi-finished fiber product 740 comes as a long, wide material from a supply roll 741 and runs to the right into the device 711. From above come a wide upper film layer 731 and a similarly wide lower film layer 732, each also from corresponding supply rolls. The film layers 731 and 732 are fed, so to speak, flat against the semi-finished fiber product 740 via corresponding deflection rollers 733 and applied from below and above, respectively.By means of an upper side welder 755 and a lower side welder 756, which press against each other and are, for example, rotating heated wheels, as is known from film packaging machines, the two film layers 731 and 732 are welded together in an airtight manner. This forms a covering 739 or a tube 730. This welding takes place laterally outside the semi-finished fiber product 740 enclosed between them. Alternatively, the side welders 755 and 756 can also be arranged further to the right in the direction of travel L, as shown in FIG. Fig. 14 is shown in dashed lines.

[0063] The aforementioned side welders 756 and 755 thus form a film tube 730 as the aforementioned wrapping 739. At the beginning of the process, the wrapping 739 can be closed at the end by transverse welding, as already described above. An upper compression roller 723 and a lower compression roller 724 are provided fairly far to the right in the running direction L, similarly configured to the one above. These are arranged in relation to one another in the same way as described above; moreover, they can be configured in the same way. Slightly in front of or to the left of these in the running direction L are an upper pre-compression roller 726 and a lower pre-compression roller 727, which are configured and arranged in relation to one another in the same way as described above. Liquid resin 745, for example, is provided in a bubble 746 between them, both above the semi-finished fiber product 740 and below it, i.e., on the top and bottom sides.Thus, by means of the compression rollers 723 and 724, the semi-finished fiber product 740 is particularly well impregnated with the liquid resin 745 or the liquid matrix system.

[0064] The only special feature is that the upper pre-compression roller 726 has a circumferential roller groove 728, which can also be designed differently, as can the lower pre-compression roller 727. The roller groove 728 allows a rigid feed pipe 716 coming from the left to run virtually above the semi-finished fiber product 740 or laterally next to it in the film wrapping. This allows the liquid resin 745 to be dispensed from the free end of the feed pipe 716, advantageously continuously, or possibly also in intervals. The aforementioned roller groove 728 is provided to prevent this liquid resin 745 from escaping from the bladder 746 in front of the pre-compression rollers, in particular past the feed pipe 716. It is intended to ensure that the upper pre-compression roller 726 or both compression rollers seal the area above or next to the introduction pipe 716, so to speak, so that no liquid resin 745 can get in front of it.Shown here is a substantially rounded roller groove 728, in which the insertion tube 716 is also correspondingly rounded. Advantageously, the insertion tube 716 can have a rectangular cross-section, possibly also a cross-section that is semicircular or triangular at the top, which is easier to seal. Thus, in the continuous process shown here, the liquid resin 745 can be applied to the semi-finished fiber product 740, in particular also to the area where the sheath 739, which is formed from the two film layers 731 and 732, is compressed.

[0065] To achieve the second effect of creating negative pressure in the wrapping, particularly before the impregnation area, i.e., in the running direction L, in front of the pre-compression rollers 726 and 727, a suction pipe 738 extends from the side into the wrapping. Similar to the insertion pipe 716, the suction pipe 738 also extends in the running direction L in front of the side welders 755 and 756 into the wrapping 739, i.e., between the two film layers 731 and 732. It is connected to a previously described vacuum pump via a suction hose 737. A negative pressure is thus generated in the wrapping via the suction pipe 738. Since the wrapping is closed at the end as seen in the running direction L and also at the sides by means of the side welders 755 and 756, it is only open to the left. Welding is not possible here.For this purpose, however, an upper push-off roller 758 and a lower push-off roller 759 are provided, which bear against each other with relatively high pressure and, so to speak, seal the enclosure across its width, largely airtight. Since the suction pipe 738 projects beyond this in the running direction L, a largely enclosed space is formed in which the negative pressure desired and required according to the invention can be generated. However, since both the suction pipe 738 and the previously described insertion pipe 716 must extend into this space past the push-off rollers, at least the upper push-off roller 758, possibly also both mirror-images of each other, has a roller groove 760a for the insertion pipe 716 and a roller groove 760b for the suction pipe 738. Due to the required sealing properties, particular attention must be paid to the coordination of the cross-sections.If the roller grooves 760a and 760b, which can also apply to the roller groove 728 on the upper pre-compression roller 726, are divided between both pressure rollers 758 and 759, problems caused by a lateral shortening of one of the film layers 731 or 732 can be avoided. Furthermore, even pipes with a circular cross-section can be sealed effectively. Finally, it can advantageously be provided that the feed pipe 716 and the suction pipe 738 are formed as a structural unit, so that only a single area needs to be sealed. The two pipe cross-sections can then be arranged side by side or coaxially surrounding each other.

[0066] For the pressure rollers 758 and 759, it can advantageously be provided that, apart from roller grooves 760, they not only have a constant cross-section or diameter, but are also adapted or adaptable to the thickness and width of the introduced semi-finished fiber product 740. Then, the pressure rollers 758 and 759 can seal as effectively as possible in order to create the best possible negative pressure inside the casing 739. However, an increased pumping capacity is expected to be provided on the suction hose 737, at least more than in the previously described embodiments.

[0067] Behind the compression rollers 723 and 724, the fully impregnated semi-finished fiber product 740 can be wound onto a roll supply 750. This roll supply can, for example, contain 10 m to 50 m or even 100 m of liquid resin-impregnated semi-finished fiber product 740 and can then be transported to another location for processing. The resulting, nearly endless and impregnated semi-finished fiber product 740 can be cut into individual pieces, possibly also shaped or punched.

Claims

1. Method for impregnating a semi-finished fibre product (40, 740) with a liquid matrix system (45, 745), in particular a textile or a fibre composite (40, 740) of technical fibres with a liquid resin (45, 745), wherein the following steps are carried out: - the semi-finished fibre product (40, 740) in flat form is provided and is placed in flat form in a flexible and sealable envelope (539, 739), - the liquid matrix system (45, 745) is introduced into the envelope (539, 739), preferably separately from and at a distance from the semi-finished fibre product (40, 740), before or after introduction of the semi-finished fibre product (40, 740) into the envelope (539, 739), - pressure is applied to the envelope (539, 739) from above and / or from below, preferably at least 0.1 N / cm2, as compression (Z), starting at one end region of the envelope (539, 739) over the entire width of the envelope (539, 739), continuously and without gaps, - the compression (Z) is carried out continuously or without interruption along a direction of travel (L) of the process, which runs from a first end region (34) of the envelope (539, 739) to a second end region (35) of the envelope (539, 739), at least over the entire length of the semi-finished fibre product (40, 740), wherein the compression (Z) begins at a region (34) of the envelope (539, 739), and wherein the liquid matrix system (45, 745) is located in the direction of travel (L) between the beginning compression (Z) and the semi-finished fibre product (40, 740), characterised in that an additional pre-compression (V) is carried out continuously and without gaps over the entire width of the envelope (539, 739) in the direction of travel (L) before the compression (Z).

2. Method according to claim 1, characterised in that a negative pressure is applied to the inside of the envelope (539, 739), preferably at the second end region (35), in particular all air is sucked out of the envelope (539, 739), the liquid matrix system (45, 745) and the semi-finished fibre product (40, 740) having preferably been introduced into the envelope (539, 739) before the application of the negative pressure and the envelope (539, 739) having been closed and sealed except for a suction connection (36, 436) in the second end region (35).

3. Method according to claim 2, characterised in that the envelope (539, 739) is closed and sealed except for at least one suction connection (36, 436), preferably the envelope (539, 739) being closed and sealed after the introduction of the liquid matrix system (45, 745), wherein preferably the liquid matrix system (45, 745) has been introduced in a region between the first end region (34) and the semi-finished fibre product (40, 740), has been closed at a further previously open region, in particular at the second end region (35).

4. Method according to one of the preceding claims, characterised in that the compression (Z) is carried out in a strip-like or line-like manner, in particular at least as wide as the envelope (539, 739) in the direction perpendicular to the direction of travel (L), wherein the compression (Z) is preferably carried out by means of at least one compression profile (23, 24, 123, 124, 223, 224, 323, 324, 423, 424, 723, 724), in particular with a rotating compression roller (23, 24, 123, 124, 223, 224, 323, 324, 423, 424, 723, 724).

5. Method according to one of the preceding claims, characterised in that the pre-compression (V) takes place at a distance of 2 cm to 10 cm in the direction of travel (L) before the compression (Z).

6. Method according to one of the preceding claims, characterised in that the pre-compression (V) is carried out in a strip-like or line-like manner, in particular at least as wide as the envelope (539, 739) in the direction perpendicular to the direction of travel (L), the pre-compression (V) preferably being carried out by means of at least one pre-compression profile (26, 27, 126, 127, 226, 227, 326, 327, 426, 427, 726, 727).

7. Method according to claim 5 or 6, characterised in that the pre-compression (V) is carried out less strongly than the compression (Z), in particular with a pressure between 5% and 70% of the compression (Z) or with more distance.

8. Method according to one of the preceding claims, characterised in that the compression (Z), in particular also the pre-compression (V) according to one of claims 5 to 7, is carried out to such an extent that the envelope (539, 739) is pressed against the semi-finished fibre product (40, 740) from both opposite sides.

9. Method according to one of claims 6 to 8, characterised in that the compression (Z) and / or the pre-compression (V) begins at a region (34, 35) of the envelope (539, 739) together with the semi-finished fibre product (40, 740) therein, at which no liquid matrix system (45, 745) is located, wherein preferably at the beginning of the pre-compression (V) and the compression (Z) the liquid matrix system (45, 745) is located between the pre-compression (V) and the compression (Z).

10. Method according to any one of claims 6 to 9, characterised in that during the compression (Z) and the pre-compression (V), the distance in the direction of travel (L) between the compression (Z) and the pre-compression (V) does not increase as soon as and as long as the compression (Z) onto the semi-finished fibre product (40, 740) takes place, preferably the distance becomes smaller.

11. Method according to claim 10, characterised in that the pre-compression (V) begins at a distance from the front end of the semi-finished fibre product (40, 740) counter to the direction of travel (L), the distance preferably being at most 5 cm, the compression (Z) in particular being started first along the direction of travel (L) before the pre-compression (V) takes place and / or is moved along the direction of travel (L).

12. Device for carrying out the method according to one of the preceding claims, wherein it comprises - a flat / surface support (12, 312, 412, 512) for the envelope (539, 739), - means (16, 716) for introducing the liquid matrix system (45, 745) into the envelope (539, 739), - means (37, 738) for extracting air from the envelope (539, 739), - means (23, 24, 123, 124, 223, 224, 323, 324, 423, 424, 723, 724) for compressing the envelope (539, 739), - means for producing a relative movement between the envelope (539, 739) and the means (23, 24, 123, 124, 223, 224, 323, 324, 423, 424, 723, 724) for compressing the envelope (539, 739) relative to one another, characterised in that for the pre-compression (V) it has at least one pre-compression profile (26, 126, 226, 326, 426, 726) on at least one side of the envelope (539, 739), wherein the pre-compression profile (26, 126, 226, 326, 426, 726) has a width which corresponds at least to the width of the envelope (539, 739) or is as wide as the pre-compression profile (26, 126, 226, 326, 426, 726). as wide as the compression (Z), wherein a counter-pre-compression profile (27, 127, 227, 327, 427, 727) is arranged opposite the pre-compression profile (26, 126, 226, 326, 426, 726) on one side of the envelope (539, 739) on another opposite side of the envelope (539, 739).

13. Device according to claim 12, characterised in that it has at least one compression roller (23, 24, 123, 124, 223, 224, 323, 324, 423, 424, 723, 724) for the compression and the envelope (539, 739) during the process or, as the case may be, during the compression (Z). during the compression (Z) between the support (12, 312, 412, 512) and the compression roller (23, 24, 123, 124, 223, 224, 323, 324, 423, 424, 723, 724), wherein the compression roller (23, 24, 123, 124, 223, 224, 323, 324, 423, 424, 723, 724) is at least as wide as the envelope (539, 739), wherein this compression roller (23, 24, 123, 124, 223, 224, 323, 324, 423, 424, 723, 724) is rotatable along the direction of travel (L) during compression (Z), in particular is rotatable without slippage between the compression roller (23, 24, 123, 124, 223, 224, 323, 324, 423, 424, 723, 724) and the envelope (539, 739).

14. Device according to claim 13, characterised in that the compression roller (23, 123, 223, 323, 423, 723) is arranged above the envelope (539, 739) and a counter-compression roller (24, 124, 224, 324, 424, 724) is arranged opposite the latter below the envelope (539, 739) in such a way that in a nip between the compression roller (23, 123, 223, 323, 423, 723) and the counter-compression roller (24, 124, 224, 324, 424, 724) the envelope (539, 739), if necessary with the semi-finished fibre product (40, 740) extending therein, wherein the compression roller (23, 123, 223, 323, 423, 723) and the counter-compression roller (24, 124, 224, 324, 424, 724) are rotatable in opposite directions, wherein preferably the nip is set such that at a predetermined point it is the thickness of the semi-finished fibre product (40, 740) impregnated with liquid matrix system (45, 745) plus the thickness of the envelope (539, 739).

15. Device according to one of claims 12 to 14, characterised in that the pre-compression profile (26, 27, 126, 127, 226, 227, 326, 327, 426, 427, 726, 727) is a round rod or a round roller.