Method for manufacturing parts using a heating device in a supply system

Abstract

The present invention relates to a method for manufacturing fiber-reinforced parts, wherein in a base material impregnation process, a fabric made of reinforcing fibers is treated with a thermosetting base material. At least one direct supply system (3) is placed between a storage container (2) and an impregnation unit (1), and the base material reaches the impregnation unit from the storage container through at least one direct supply system. In this method, each of the at least one supply system has at least one heating device (4), and according to the method for manufacturing fiber-reinforced parts, the thermosetting base material is heated by at least one heating device of the at least one supply system to the temperature necessary to impregnate the fabric made of reinforcing fibers with the base material, in at least one supply system only.

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing fiber-reinforced parts, which requires heating only a small portion of the necessary base material. The present invention further relates to a supply system for use in the method, having a corresponding heating device, and equipment for carrying out the method using such a supply system. The present invention further relates to a storage container for the method and equipment.

[0002] Methods for impregnating fabrics to manufacture fiber-reinforced parts are generally known. Equipment used for impregnation is also known. European Patent No. 3390023 proposes an impregnation method in which the base material is present in a frozen state. The base material is partially supplied to an extruder having a heating device, which heats the base material to the impregnation temperature. The objective of the method according to European Patent No. 3390023 is that the base material is not stored at room temperature. German Patent Application Publication No. 102005053690 describes, for example, tools, configurations and methods for manufacturing parts. In this method, storage bags filled with resin are placed in a storage chamber. The storage chamber is in contact with an operating chamber in which the semi-finished product is located. The storage bags are made from thin-walled material and contain the amount of base material required to manufacture the part. The storage chamber can receive compressed air, or the operating chamber can be exhausted. In either case, the resin material heated in the storage chamber enters the operating chamber from the storage bags to manufacture the part by impregnation. A similar method is also known from European Patent No. 29563820, which describes a collapsible bag-type packaging and connection system, where the bag can be filled with, for example, a base material and emptied by manual or pump pressure (positive or negative pressure). European Patent No. 0370564 describes the manufacture of storage bags for plastic materials and the subsequent use of the storage bags. To manufacture the package, the storage bag is placed in or on the molded form such that the outlet opening of the storage bag is within the injection channel. Pressure is then applied to the storage bag so that the material to be processed enters the cavity of the molded form. U.S. Patent No. 6,071,457 discloses an apparatus comprising at least a storage container, a feeding system, and an impregnation tool. In the RTM (Resin Transfer Molding) method, the volume of the storage container can be reduced so that the impregnating material enters the manufacturing cavity from the storage container through the feeding system. A feeding system for liquid resins (e.g., epoxy) is known from U.S. Patent Application Publication No. 2005 / 0023712. The system has a storage bag for storing liquid material, the volume of which can be reduced (e.g., under pressure) to improve material delivery.The improved resin supply system is also described in U.S. Patent Application Publication No. 2019 / 0152111.

[0003] Some drawbacks of the methods and equipment from this prior art are that the material used for impregnation (referred to as resin or base material) is heated as a unit, completely up to the processing temperature (within the corresponding storage container of the material). In the case of a longer impregnation process, the corresponding temperature of the base material must be maintained throughout the entire process, and temperature fluctuations must be prevented. On the one hand, this is associated with high energy costs, and on the other hand, temperature fluctuations of the base material can lead to undesirable side effects that may pose safety risks (uncontrolled exothermic reactions). Furthermore, many reactive base materials must discard the once-heated base material residue and undergo rapid aging at the processing temperature such that they cannot simply be used in another process. Additionally, the complete heating of the entire base material as a unit results in an initial cross-linking reaction of the base material before the impregnation of the fabric, depending on the selected base material. This can lead to contamination (or damage) of the equipment and the production of low-quality components. This can only be prevented by selecting a base material system that cross-links slowly, resulting in an inconvenient increase in the process time for manufacturing the components.

[0004] The method according to European Patent No. 3390023 does not heat the entire base material (only partially) in a single heating operation, but still the base material must exist as a frozen base material, and in a longer process, the material must be cooled so that the base material remains in a frozen state. In either case, this requires energy and time. Then, more energy is required to heat the base material to the impregnation temperature than when using the material at room temperature.

[0005] U.S. Patent Application Publication 2004 / 0070114 discloses a system and method for RTM (Return to Molding) technology in which fibrous materials are processed. The system has two storage containers for resin material, various feeding systems, and a number of heating elements. The heating elements are placed on the storage containers and melt only the upper layer of resin material in the storage containers, so that this layer can be pumped out of the storage containers. This results in the resin material in the storage containers being unevenly heated. The resin material is fed through a first feeding line, through subsequent feeding lines to further feeding lines, and from there into the mold. In all cases, all feeding lines have heating elements. European Patent No. 2 656 991 describes a storage container (e.g., in the form of a bag) and a corresponding method for an apparatus for processing casting resin. According to this document, casting resin is fed into a mold for manufacturing parts via at least one feeding device. Excess casting resin is taken up by storage containers connected to both the feeding device and the mold. Therefore, the storage container functions as a buffer store for reactive casting materials, and excess casting resin can be transported from the storage container into the mold as needed. The reactive mixture can be further guided through a heat exchanger, which is provided in the storage container and / or the supply device. U.S. Patent No. 6,136,236 discloses a method and apparatus for impregnating fiber pellets. The fiber pellets should have a fiber content of more than 58%, and the main focus of the literature is the pressure fluctuations during impregnation. The resin material is placed in a storage container and transported into the mold via a supply line. A heat exchanger is provided in the supply line and is intended to ensure that the resin material has the correct temperature before reaching the mold. U.S. Patent No. 6,168,408 discloses an apparatus for impregnating composite materials, in which the flow rate and pressure of the impregnating matrix can be adapted according to the product to be impregnated. The apparatus comprises at least one storage container, a supply system, and at least one mold. One or more storage containers are placed in a tank also suitable for heating one or more storage containers. The supply system may include a heat exchanger.U.S. Patent No. 5,518,388 discloses an apparatus and method for RTM, in which the resin is supplied from a storage container to a mold via various supply lines. The storage container and mold can be heated by heating elements. The apparatus further includes a preheater, which is also intended to heat the resin.

[0006] However, a drawback of the described method is that the base material is introduced from the storage container to the product to be impregnated via a supply line system, and the temperature required for impregnation must be maintained by a heat source along the way. In particular, highly reactive base material systems cannot be adequately processed by this method due to the high risk of premature crosslinking within the supply system.

[0007] Therefore, the object of the present invention was to eliminate or at least mitigate the drawbacks that occur in the prior art.

[0008] This objective was achieved by the method described in claim 1.

[0009] The present invention proposes a method for manufacturing fiber-reinforced parts, in which a fabric made of reinforcing fibers (so-called high-strength fibers) is processed with a thermosetting base material in a base material impregnation process. The thermosetting base material required for impregnation is stored in a storage container, the fabric made of reinforcing fibers is stored in an impregnation unit, and at least one direct supply system is provided between the storage container and the impregnation unit. The thermosetting base material enters the impregnation unit directly from the storage container via at least one direct supply system, and each of the at least one direct supply system has at least one heating device. In the method for manufacturing fiber-reinforced parts, the thermosetting base material is heated by at least one heating device to the temperature required to impregnate the fabric made of reinforcing fibers with the thermosetting base material, only in at least one direct supply system. In the storage container, the thermosetting base material is present at room temperature during the process, and room temperature is defined as a temperature of 16°C to 26°C. In one embodiment, the base material is present at room temperature of 20°C to 25°C.

[0010] Therefore, according to the present invention, the thermosetting matrix (hereinafter also simply referred to as the matrix) is not completely heated as a unit and does not exist completely frozen as a unit. Advantageously, only the proportion of the matrix that flows into the impregnation unit through at least one direct supply system is heated. Advantageously, less energy is required to heat or cool the matrix, as it is not necessary to maintain a larger amount of matrix at the processing temperature or frozen state throughout the entire process and then heat it to the impregnation temperature. Furthermore, this novel method is also suitable for highly reactive matrixs because the thermal pre-pressure of the material, particularly the time between heating and impregnation, is especially short. Moreover, the thermosetting matrix is ​​intended to reach the impregnation unit via a direct supply line, which also reduces the residence time of the matrix in the supply system. Because the residence time of the matrix in the supply system is short and the time the matrix exists heated to the impregnation temperature is short, so-called highly reactive two-component resin systems can also be used with this system without the need to later add the second component separately. A further advantage of the new method is that the base material, which is not (ultimately) required for impregnation, is generally not heated to the impregnation temperature and can therefore be easily reused in other ways. This reduces the proportion of base material waste.

[0011] According to the present invention, a direct supply system is used between a storage container and an impregnation unit, and the thermosetting matrix is ​​directly transported to the impregnation unit via the direct supply system, where it is heated (to the impregnation temperature). Such a system and such transport explicitly exclude the case where the matrix is ​​guided through multiple supply lines arranged successively (in series). Thus, the matrix can indeed be transported directly from the storage container to the impregnation unit via multiple direct supply systems, but each direct supply system constitutes the shortest connection between the storage container and a selected area of ​​the impregnation unit. Therefore, the transport of the matrix from a first supply system to a subsequent supply system and then to the impregnation unit is not a direct supply system within the scope of the present invention. A system in which the matrix is ​​supplied to the impregnation unit via various storage containers arranged before and after by a supply system is also not within the scope of the present invention. The direct supply system according to the present invention is intended to transport the matrix by the shortest path and as quickly as possible from the storage container to the impregnation unit. Preferably, the residence time of the matrix in the supply system is less than or equal to the time required to heat the matrix in the supply system to the impregnation temperature.

[0012] According to the present invention, the base material is similarly heated to the impregnation temperature within the direct supply system. The impregnation temperature required for impregnation is a temperature at which the base material has sufficiently good flow properties (i.e., low viscosity) for complete impregnation of the fabric within the impregnation unit. The impregnation temperature is between 50 and 140°C, preferably between 70 and 120°C, preferably between 50 and 120°C, preferably between 70 and 140°C. For complete impregnation, the base material must saturate all areas of the fabric. At the impregnation temperature, the base material has a viscosity of less than 1000 mPa*s, preferably less than 800 mPa*s, preferably less than 500 mPa*s, preferably less than 350 mPa*s, preferably less than 200 mPa*s, preferably less than 150 mPa*s, preferably less than 100 mPa*s, and preferably less than 50 mPa*s.

[0013] In one exemplary embodiment, the base material may be further heated within the impregnation unit so that it hardens. In one exemplary embodiment, the impregnation temperature is selected so that the base material hardens as well, and in this case, it is particularly preferable to select a short supply system so that hardening does not occur within the supply system, or the impregnation temperature within the supply system is reached only at the end of the supply system (just before entering the impregnation unit).

[0014] In one embodiment, the supply system is a separate unit. This means that the supply system can be introduced into the impregnation equipment independently of the storage container or impregnation unit, and can be controlled independently of the impregnation unit or storage container. In another embodiment, the supply system is part of the storage container and is inremovably connected to it.

[0015] Preferably, each direct supply system has only a single heating device.

[0016] In one embodiment, the heating device is in detachable contact with at least one direct supply system.

[0017] Hereinafter, at least one direct supply system will also be referred to simply as a supply system. However, it should be understood that one or more direct supply systems may be used in both the method for manufacturing the components and the equipment for manufacturing the components.

[0018] In one embodiment of the method and the apparatus for carrying it, a storage container is used through which multiple supply systems lead to an impregnation unit, and each supply system has at least its own heating device. In another embodiment of the method and apparatus, multiple supply systems and storage containers are used, and each supply system is connected to a different storage container, but all supply systems lead to a single impregnation unit, and each supply system has at least its own heating device. Thus, embodiments relating to storage containers should be understood to also apply to the use of multiple storage containers in the method and / or apparatus. When three or more storage containers are used in the method and / or apparatus, these storage containers can be configured identically or differently from one another. For example, the first storage container may have a pressure device, but the second storage container may not. However, when multiple storage containers are used, the base material is not transferred from the first storage container to the second (or third) storage container, and then to the impregnation unit, but instead, the base material is always led directly from the storage container to the impregnation unit via the supply line.

[0019] For the purposes of describing this invention, the terms matrix and base material, resin and resin material are used synonymously. This is understood to mean a thermosetting material for impregnating a fabric made of reinforcing fibers, the reinforcing fibers being particularly preferably carbon fibers and / or glass fibers. Fabric is understood to mean a cloth, UD layup, nonwoven material, or mixture of the aforementioned materials. Fabric may also be a multiaxial layup, a so-called non-crimped cloth (with or without nonwoven material). Pellets, even if they consist of fibrous material, do not constitute a fabric within the scope of this invention. The term impregnation is intended to encompass any type of part manufacturing in which a fabric made of reinforcing fibers becomes a part by the addition of a base material (and optionally heat and pressure). A part is any portion that forms a final product, either alone or together with other parts.

[0020] Whenever the term "room temperature" is used herein, it is intended to mean a temperature of 16°C to 26°C, preferably 20°C to 25°C.

[0021] According to the present invention, the base material is not heated at all in the storage container. When the base material is not heated at all in the storage container, this means that the base material in the storage container is simply at room temperature, and no additional heating is performed. Therefore, the base material is also not frozen in the storage container. Thus, it is advantageous that heating the base material to the impregnation temperature can be done more quickly and with less energy than when using a frozen base material.

[0022] In one example of the proposed concept, during the entire impregnation process for manufacturing fiber-reinforced parts, less than 30%, preferably less than 20%, preferably less than 10%, of the base material required for impregnation is heated simultaneously in the supply system (or all supply systems together). It is understood that in the process of the impregnation method, the entire base material must generally be heated so that impregnation can take place. However, in the proposed method, only a small amount of material is always heated in the supply system, while the majority of the base material is not heated and therefore remains at room temperature in the storage container.

[0023] In one embodiment of this method, an impregnation base material having a viscosity of 50,000 mPa*s to 120,000 mPa*s, preferably 80,000 mPa*s to 100,000 mPa*s, at room temperature (16°C to 26°C) is selected as the thermosetting base material. Nevertheless, it is understood that this method can be carried out when using thermosetting base materials having different viscosities. For example, even when a non-flowing or nearly non-flowing base material is used at room temperature, the base material can pass from the storage container to the supply system without heating the base material in the storage container. For this purpose, for example, pressure can be applied to the storage container so that its volume is reduced and even non-flowing or nearly non-flowing base materials are forced into the supply system.

[0024] In one embodiment of the concept, the supply system has a control unit that can measure and / or adjust the pressure, flow rate and / or temperature of the base material in the supply system in a method of manufacturing parts. Advantageously, this ensures that the base material reaches the impregnation unit at the correct impregnation temperature and / or correct flow rate and / or correct pressure, so that the quality of part manufacturing is reproducibly high. In a further embodiment, the supply system further includes a degasser so that degassing is possible within the supply system. This prevents bubbles (areas without base material) in the part, even if the base material has not been degassed beforehand in a storage container. However, the base material may already be degassed, and the degassed state of the base material can be maintained until impregnation in the manner of this concept. Thus, storage, heating, supply and impregnation are carried out without contact with gas or gas mixtures such as air, for example.

[0025] In a further embodiment of the concept, the feeding system has at least one sieve that affects the pressure, viscosity, and / or flow rate of the base material. The at least one sieve is preferably located at the transition point from the feeding system to the impregnation unit. Depending on the mesh size and thickness of the mesh wire of the at least one sieve, the base material can pass through the sieve only if it has the appropriate viscosity at a specified pressure. Simultaneously, the at least one sieve may also affect the flow rate. Preferably, the at least one sieve can be reversibly removed from the feeding system. For example, the at least one sieve can be provided on or as part of a connecting piece of the feeding system. Depending on the base material used and / or desired component, the at least one sieve can be replaced to allow for easy setting or monitoring of other process parameters. Preferably, the sieve may also be used additionally or alternatively to mix the base material within the feeding system. For example, the feeding system may have a number of sieves having different functions within the feeding system (for this purpose, also having different mesh sizes and mesh wire thicknesses).

[0026] In embodiments where multiple supply systems are used, the supply systems can also transport different resin materials to the impregnation unit. In particular, when a part is impregnated with a multi-component base material, the various components can be transported through the supply system and then combined only within the impregnation unit or in the end region of the supply system immediately preceding the impregnation unit. For this purpose, the various components are stored in different storage containers, each connected to the impregnation unit via its own direct supply system. In another embodiment, the supply system may have access points from which additives to the base material can be introduced into the supply system.

[0027] In a further embodiment of this concept, the volume of the storage container is reduced by a pressure device during the manufacture of the fiber-reinforced part. As the volume is reduced, the base material is pushed out of the storage container into the supply system, preferably so that little or no base material remains in the storage container at the end of the method. Preferably, the volume of the storage container is reduced reversibly so that, after being emptied, the storage container remains reusable and can be refilled with base material. In one embodiment of the concept, the storage container can also be used to manufacture a number of parts in a number of manufacturing methods (or manufacturing cycles), and therefore can contain a corresponding amount of base material. In each individual method for manufacturing a part, the volume of the storage container is reduced by a specific percentage of the volume of the storage container that existed up to that point.

[0028] In one embodiment of this method, a vacuum unit or a positive pressure unit and / or a mechanical press unit is used as a pressure device to reduce the volume of the storage container. For example, a vacuum pump can be used to slowly evacuate the impregnation unit during the manufacturing of the part. Furthermore, a compression device can be attached to the storage container, thereby reducing the volume of the storage container from above toward the supply system during the process of the part manufacturing method. In both cases, the base material is pressed or drawn out of the storage container toward the supply system, thereby entering the supply system.

[0029] In one embodiment of the method, at least one heat exchanger is used as at least one heating device. Preferably, the heat exchanger is operated using waste heat from other processes. The heat exchanger can be arranged spirally around, for example, a supply system or a part of the supply system and can heat the pipes (or a single pipe) of the supply system. The base material is arranged inside the pipes of the supply system and is in direct contact with them. If a material with good thermal conductivity is used for the pipes, the heat of the pipes is directly transferred to the base material, and heating can be performed without direct contact between the heat source and the base material.

[0030] Of course, the at least one heating device may also (additionally or alternatively) include another heat source such as an infrared radiator or a heating coil. It is also possible to combine different heating devices for heating the base material, and in one embodiment, it is also possible to have a stepwise increase in the heating temperature by different heating devices.

[0031] The supply system is preferably not an extruder.

[0032] A further subject of this concept relates to a supply system for the method described above. Therefore, if necessary, the explanations made so far are intended to be applied to the supply system as well. Conversely, the explanations regarding the supply system described below are also intended to be applied to the method of manufacturing parts using such a supply system.

[0033] A supply system for the method (as described above) will preferably have a tubular structure having two end pieces facing each other. The first end piece can be reversibly or permanently connected to an impregnation unit, and the second end piece can be connected to a storage container. The supply system has at least one heating device that heats a thermosetting matrix having a temperature of 16°C to 26°C, preferably 20°C to 25°C, from the storage container to the impregnation temperature, and the matrix flows from the storage container through the supply system to the impregnation unit. The supply system more preferably has a control unit that can check and / or change the temperature and / or flow rate of the heated thermosetting matrix before it enters the impregnation unit. Through the supply system, the thermosetting matrix is ​​transported directly from the storage container to the impregnation unit, and the supply system constitutes the shortest, preferably only tubular connection between the two components for this purpose. When reversible connections of the end pieces are used, the supply system can be advantageously used for different methods of manufacturing the components, as well as for connecting pieces. Therefore, end pieces are preferably standardized in terms of shape and size, or selected according to the storage container and / or impregnation unit and / or required process parameters used, and a number of end pieces are available that can be reversibly attached to the supply system. In one embodiment, the supply system is fixed to an end piece on the storage container and can be reversibly connected to the impregnation unit by the end piece.

[0034] In one embodiment, the supply system has lengths of less than 15 meters, less than 10 meters, less than 5 meters, less than 3 meters, less than 1.5 meters, and less than 1 meter. The length of the supply system corresponds to the path length between the storage container and the impregnation unit.

[0035] In one embodiment, the supply system and the storage container form a unit that cannot be separated from each other without being destroyed.

[0036] In one embodiment, the supply system is formed by a single tubular connector that constitutes the shortest connection between the storage container and the impregnation unit. In another embodiment, the supply system is formed by a plurality of tubular connectors that extend substantially parallel to each other and in both cases form the shortest connection between the storage container and the impregnation unit.

[0037] In one embodiment of the supply system, the supply system has at least one control unit in the region of at least the first end piece. The control unit is preferably intended to allow the temperature and / or flow properties of the heated base material to be checked and / or modified before it enters the impregnation unit. For example, the control unit may have a thermal element (e.g., a contact thermometer) for measuring the temperature of the base material. If the control unit detects a temperature difference between a set temperature to be achieved (target temperature) and the actual temperature of the base material (actual temperature), the control unit may, for example, act on at least one heating device to raise or lower its temperature. The control unit may further include a device (e.g., a sieving element) for measuring the flow rate of the base material, which compares the actual value with the target value again, and, where appropriate, a device that affects the flow rate of the base material via a pressure device and the volume change of the storage container. Furthermore, temperature measurement can function as a safety monitor for early detection and prevention of undesirable curing reactions and overheating of the system.

[0038] In one embodiment, the supply system has at least one heat exchanger as at least one heating device. In one embodiment, each supply system has only a single heating device, preferably a heat exchanger.

[0039] In one embodiment, the supply system has a material that prevents or reduces the adhesion of the base material to the supply system, at least in the area that comes into contact with the base material. Preferably, the pipes for transporting the base material are made of this material.

[0040] This is advantageous because it allows for better processing of adhesive substrates, even at room temperature.

[0041] A further subject of this concept concerns equipment for manufacturing fiber-reinforced components. With regard to equipment, the description already given regarding the manufacturing method is intended to apply. Furthermore, the description of the supply system is intended to apply to the equipment. To the extent that the description of equipment relates to a method or a form of the supply system, these descriptions are also intended to apply accordingly.

[0042] As described above, the equipment will include at least one impregnation unit for impregnating a fabric made of reinforced fibers, a storage container containing a thermosetting base material for impregnating the fabric, and a direct supply system equipped with at least one heating device.

[0043] In one embodiment of the equipment, the storage container is a flexible bag. A flexible bag exists if the bag can be compressed (preferably reversibly), that is, if its volume can be reduced by, for example, compressing the bag. In one embodiment of the bag, the bag is not only compressible but also expandable, so that it is also possible to increase the volume of the bag within a certain tolerance range without damaging the bag.

[0044] In one embodiment, the bag is made of a heat-resistant polymer material (e.g., as a film bag) and has an outlet opening at one end with a connecting element for the end piece of a supply system. For example, a base material manufacturer may sell and supply base materials in corresponding bags. For part manufacturing, the bag can be inserted into a storage container, or the bag itself constitutes a storage container. By using the bag as a storage container, it is advantageous that the base material does not need to be degassed before part manufacturing. At the same time, the flexible bag allows for improved emptying (by reducing the volume of the bag) and mixing of the base material inside the bag. Preferably, the bag is designed to be resealable so that the bag can also be used as a store for base materials for various manufacturing methods.

[0045] Preferably, the bag has a supply opening that allows an additive, such as a special curing agent, to be supplied to the base material inside the bag.

[0046] In one embodiment, the bags, acting as storage containers, together with the supply system, form a unit that cannot be separated from each other.

[0047] In one embodiment of the equipment, the equipment has a pressure device that can change (preferably decrease) the volume of the storage container (preferably a flexible bag). In one embodiment, the storage container (preferably a flexible bag) itself has a pressure device.

[0048] A further subject of the present invention relates to a storage container for the described method and apparatus. The storage container is a flexible bag and has a mechanical pressure device for changing (preferably decreasing) its volume. Together with the supply system (as already described), the storage container in the form of a flexible bag forms an inseparable unit.

[0049] The descriptions of methods, supply systems, and equipment are intended to apply to storage bags as well, and vice versa.

[0050] The concept will be explained in more detail below with reference to two figures, but these figures are merely illustrative of embodiments of the concept and are not intended to be limiting. [Brief explanation of the drawing]

[0051] [Figure 1] This diagram schematically illustrates equipment for manufacturing parts with a direct supply system, where flexible resin containers are used as storage containers. [Figure 2] This diagram schematically shows another embodiment of the equipment shown in Figure 1, the difference being that it is a type that empties the storage container.

[0052] Figure 1 schematically shows the equipment for manufacturing fiber-reinforced parts. The fabric to be impregnated is placed in the impregnation unit 1. The storage container 2 contains the base material into which the fabric will be impregnated and become the part. A direct supply system 3 is provided between the storage container 2 and the impregnation unit 1, and the base material from the storage container 2 passes directly (and therefore without detours) through the supply system 3 to the impregnation unit 1. The supply system 3 has a heating device 4 designed as an inline heater. The heating device 4 heats the base material from the storage container 2 to the temperature required for impregnation. In the storage container 2 itself, the base material is at room temperature. Therefore, heating of the base material occurs only partially in the supply system 3. Thus, the heating device 4 of the supply system 3 always fully heats only a small portion of the base material that is still present (and has not yet reached the impregnation unit 1), which then flows into the impregnation unit 1 to impregnate the fabric. The base material is not fully heated in the storage container 2, and some or all of the base material in the storage container 2 is not heated to the temperature corresponding to the impregnation temperature of the base material. According to the embodiment of Figure 1, the storage container 2 is a bag that can be acted upon during the manufacturing process by a pressure roller acting as a pressure device 6. The pressure roller 6 can reduce the volume of the bag (by squeezing the bag) so that the base material inside the bag is pushed into the supply system 3 in the direction of the supply system 3. The supply system 3 according to Figure 1 further includes a control unit 5 located immediately adjacent to the impregnation unit 1. In this example, the control unit 5 has sensors that can measure the pressure, volumetric flow rate and / or temperature and / or further characteristic values ​​of the base material. The control unit 5 can also control the pressure device 6 and / or the heating device 4. For example, the control unit 5 can raise or lower the temperature of the heating device 4, move the pressure roller 6 in the direction of the supply system 3 or the opposite direction, and / or change (increase or decrease) the pressure on the storage container 2.

[0053] In the exemplary embodiment shown in Figure 2, a flexible resin container (e.g., bag 7) is placed inside the storage container 2. The impregnation unit and / or supply system 3 can be exhausted during the manufacturing process of the part (i.e., impregnation of the base material into the fabric) so that the base material moves toward the supply system 3. In another embodiment, the storage container 2 can receive compressed air so that the base material moves from the storage container 2 to the supply system 3. The base material receives the temperature required for impregnation only from the heating device 4 (in-line heater) in the supply system 3. However, the base material in the supply system 3 is heated completely to the impregnation temperature. As a result, only a small portion of the base material that is still present (base material that has not yet reached the impregnation unit) is always heated to the impregnation temperature in the supply system 3. This type of heating is more energy-efficient and also beneficial to the base material. Since the base material in the storage container 2 that is not needed is not heated, the relevant crosslinking reaction does not occur within the base material. As a result, the unused base material can be used in other processes and does not need to be discarded (because it is already over-crosslinked). Furthermore, highly reactive matrix systems can also be used without causing undesirable crosslinking of the matrix during the already slow impregnation process in the storage container 2 or supply line. Advantageously, in the proposed equipment and method, the matrix is ​​only brought to the impregnation temperature immediately before impregnation, thereby substantially reducing or completely preventing pre-crosslinking reactions. In the impregnation unit 1, the fabric impregnated with the matrix can be further heated as needed to achieve complete crosslinking and / or curing of the matrix for part manufacturing. Furthermore, the impregnation unit 1 can also be designed to maintain the temperature of the matrix within the impregnation unit 1 until complete impregnation of the fabric is achieved. The impregnation unit 1 can also be subjected to pressure for part manufacturing.

Claims

1. A method for manufacturing fiber-reinforced parts using a thermosetting matrix, wherein, in order to manufacture the fiber-reinforced parts, a matrix impregnation step is performed in which a fabric made of reinforcing fibers is processed with a thermosetting matrix, the thermosetting matrix necessary for impregnation is stored in a storage container (2), the fabric made of reinforcing fibers is stored in an impregnation unit (1), at least one direct supply system (3) is provided between the storage container (2) and the impregnation unit (1), and the thermosetting matrix is ​​supplied from the storage container (2) to the impregnation unit via the at least one direct supply system (3). A method for manufacturing the fiber-reinforced component, wherein (1) passes directly into the at least one direct supply system (3), each of the at least one direct supply system (3) has at least one heating device (4), the thermosetting matrix is ​​heated by the at least one heating device (4) to a temperature necessary to impregnate the fabric made of reinforcing fibers with the thermosetting matrix only within the at least one direct supply system (3), and the thermosetting matrix is ​​present in the storage container (2) at room temperature of 16°C to 26°C.

2. The method according to claim 1, wherein less than 30% of the entire thermosetting matrix is ​​simultaneously heated in the at least one direct supply system (3) during the entire impregnation process for manufacturing the fiber-reinforced component.

3. The method according to at least one of claims 1 to 2, wherein the viscosity of the thermosetting base material at room temperature between 16°C and 26°C is 50,000 mPa*s to 120,000 mPa*s.

4. The method according to at least one of claims 1 to 3, wherein in at least one direct supply system (3), the pressure, flow rate and / or temperature of the thermosetting base material are measured and / or influenced via a control unit (5) of the at least one direct supply system (3).

5. The method according to claim 4, wherein at least one sieve in the at least one direct supply system (3) affects the pressure and / or flow rate of the thermosetting matrix.

6. The method according to at least one of claims 1 to 5, wherein the volume of the storage container (2) is reduced by a pressure device (6) during the manufacture of the fiber-reinforced component.

7. The method according to claim 6, wherein a vacuum unit or a positive pressure unit and / or a mechanical press unit is used as the pressure device (6).

8. The method according to at least one of claims 1 to 7, wherein at least one heat exchanger (4) is used as at least one heating device.

9. A supply system (3) for the method according to at least one of claims 1 to 8, wherein the supply system (3) has a tubular structure having two end pieces, the first end piece being connected to an impregnation unit (1), and the second end piece being connectable to a storage container (2), the supply system (3) having at least one heating device (4), the at least one heating device (4) heating the thermosetting matrix from the storage container (2), which has a temperature of 16°C to 26°C, to an impregnation temperature while the thermosetting matrix flows directly from the storage container (2) through the supply system (3) to the impregnation unit (1), the supply system (3) having a control unit (5) which can check and / or change the temperature and / or flow characteristics of the heated thermosetting matrix before it enters the impregnation unit (1).

10. The supply system (3) according to claim 9, wherein the supply system (3) consists of a single pipe.

11. The supply system (3) according to at least one of claims 9 to 10, wherein the supply system (3) has a heat exchanger as at least one heating device (4).

12. Equipment for manufacturing fiber-reinforced components according to the method of at least one of claims 1 to 8, the equipment comprising: at least one impregnation unit (1) for impregnating a fabric made of reinforcing fibers; a storage container (2) for receiving a thermosetting matrix for impregnating the fabric; and a direct supply system (3) according to at least one of claims 9 to 11, comprising at least one heating device (4).

13. The apparatus according to claim 12, wherein the storage container (2) is a flexible bag (7).

14. The apparatus according to claim 12 or 13, wherein the storage container has a mechanical pressure device for reducing the volume of the storage container.

15. A storage container for the method according to claim 1, wherein the storage container is a flexible bag and has a mechanical pressure device for changing the volume and forms a structural unit together with a supply system having a heating device.

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