Method for consolidating plastic composites

Abstract

The invention relates to a method for consolidating a plastic (2) with fibres, comprising the steps of (a) placing the plastic (2) with fibres to be consolidated on a carrier plate (10), (b) heating the plastic (2) with fibres on the carrier plate (10), (c) placing the carrier plate (10) with the heated plastic (2) with fibres on a lower part (6), (d) covering the lower part (6) including carrier plate (10) with a consolidating bell (4), wherein the consolidating bell (4) has, on the side facing the lower part (6), a membrane (5) which delimits a cavity, wherein the membrane (5) rests against the heated plastic on the carrier plate (10), (e) heating the membrane (5) and building up an excess pressure in the cavity (8), (f) cooling the carrier plate (10); (g) opening the consolidating bell (4) and removing the consolidated plastic with continuous fibres. The invention also relates to a device herefor.

Description

[0001] METHOD FOR CONSOLIDATING PLASTIC COMPOSITES

[0002] The present invention relates to a device for consolidating a plastic with fibers. The device comprises a lower part with a cooling plate, the lower part being closable with a consolidation bell. The consolidation bell has a membrane on the side facing the lower part, a cavity being formed between the inner wall of the consolidation bell and the membrane. A heat generating device is provided with which the cavity can be heated. Furthermore, the invention relates to a method for consolidating a plastic with fibers.

[0003] BACKGROUND OF THE INVENTION

[0004] Fiber-reinforced plastic composites with fibers are known to have good mechanical properties, but are currently used only in a few technical fields. The rare use of such fiber-reinforced plastic composites is due to the cost and time-consuming nature of their production, especially their consolidation. Therefore, the use of fiber-reinforced plastic composites with fibers is limited to high-tech areas where the mechanical and physical advantages outweigh the cost disadvantage.

[0005] WO 2017 / 129393 A1, DE 102021 000 921 A1 but also DE 3727 926 A1 each describe a device for molding a thermoplastic material, wherein the device has a lower part which can be covered with a bell, wherein the bell has a cavity which can be heated with a heat generating device.

[0006] DE 101 45798 A1 discloses a press for plate-shaped workpieces, such as carrier plates to be pressed with foil material for the production of furniture construction panels. The press comprises an upper and a lower press table, of which the lower press table is stationary and rests on supports. DE 10 2021 000 921 A1, EP 2 189 276 A1, and DE 198 597 98 C1 disclose pressing tools with a membrane between the pressing tools.

[0007] US 11,007,730 B2 discloses an apparatus for curing / solidifying a textile preform pre-impregnated with a polymer, comprising (i) a die without heating or cooling means, comprising a forming surface reproducing the shape of the textile preform and a mounting surface, (ii) a sealed enclosure of the preform on the die; (iii) means for applying a vacuum inside the enclosure comprising the textile preform; and (iv) a heat block comprising means for induction heating and a receiving interface cooperating with the mounting surface of the die to position it and to transfer heat between the die and the heat block.

[0008] US Pat. No. 5,037,599 A describes a process for producing non-planar thermoplastic composites from thermoplastic drapeable prepregs lining a mold cavity. A membrane is formed into the shape of the finished part using pressure and temperature.

[0009] US 5,378,134 A shows a device for molding a composite material with a lower plate and an upper plate, wherein a membrane is additionally provided through which force can be exerted by means of a fluid. Similar devices are disclosed in JP 4 670313 B2 or WO 2014 / 195799 A2.

[0010] BRIEF DESCRIPTION OF THE INVENTION

[0011] Although devices of the type mentioned above are known from the state of the art, they are not suitable for consolidating plastics with fibers to form consolidated fiber-reinforced plastic composites. The known processes for consolidating plastics with fibers are very complex.

[0012] The object of the present invention is therefore to provide a simple and cost-effective method for consolidating plastics with fibers to form consolidated fiber-reinforced plastic composites. A device suitable for this method is also to be provided.

[0013] This problem is solved on the one hand by a method for consolidating a plastic with fibers to form a consolidated fiber-plastic composite, comprising the steps:

[0014] (a) Placing the plastic to be consolidated with fibers on a carrier plate,

[0015] (b) Heating the plastic with fibers on the carrier plate

[0016] (c) Placing the carrier plate with the heated plastic with fibers on a base, (d) Covering the base together with the carrier plate with a consolidating bell, wherein the consolidating bell has a membrane on the side facing the base, which membrane defines a cavity, wherein the membrane rests on the heated plastic with fibers on the carrier plate,

[0017] (e) heating the membrane and applying an overpressure in the cavity,

[0018] (f) cooling the carrier plate;

[0019] (g) Opening the consolidation bell and removing the consolidated plastic with continuous fibers.

[0020] On the other hand, this object is also achieved by a device for consolidating a plastic with fibers, wherein the device has a lower part with a cooling plate, wherein the lower part can be closed with a consolidation bell, wherein the consolidation bell has a membrane on the side facing the lower part, wherein a cavity is formed between the inner wall of the consolidation bell and the membrane, wherein a heat generating device is provided with which the cavity can be heated, characterized in that a carrier plate is provided for the plastic with fibers, wherein the lower part has a support surface for the detachable reception of the carrier plate, wherein the carrier plate is assigned a heating device with which the carrier plate can be heated in a heating position.

[0021] The heating position can be located outside the actual device. In particular, the heating device is neither located on or in the lower part nor on or in the consolidating bell, but rather is spaced apart from the lower part and the consolidating bell. This makes it possible to heat the carrier plate outside the lower part and the consolidating bell.

[0022] The present invention provides a consolidation method and a consolidation device that compress plastics with fibers under pressure and temperature. According to the invention, it is possible to achieve very fast consolidation cycles and, moreover, to produce consolidated fiber-reinforced plastic composites with variable thicknesses without having to invest in geometry-adapted tools or molds.

[0023] At the beginning of the process, the plastic with fibers to be consolidated does not yet have its final physical material properties, such as strength, stiffness, density, etc. The final physical material properties of the consolidated plastic with fibers are only achieved through treatment with the present invention once the consolidated fiber-plastic composite has been produced.

[0024] There are different variants regarding the materials for the plastic and fibers to be consolidated (hereinafter also collectively referred to as the "starting material"): a) The fibers serve to reinforce the plastic that forms the matrix component. The fibers have greater strength and stiffness in the tensile direction than the matrix component. Preferred fibers are carbon fibers, glass fibers, and aramid fibers. Other examples are metal fibers and natural fibers such as flax and hemp. In one embodiment, the fibers are thermoplastic fibers that have a higher melting or softening temperature than the matrix component used (preferably, the melting or softening temperature is at least 30 °C higher than the matrix component). The fibers are short, long, or continuous fibers; continuous fibers whose length is in the range of the component dimensions are preferably used.The fibers can be simple rovings made only of reinforcing fibers or hybrid rovings (i.e. a roving made of reinforcing fiber and a matrix material). b) The plastic to be consolidated is particularly preferably a thermoplastic, since thermoplastics soften when heated. Examples include polyamides or polyolefins, as well as high-performance thermoplastics such as PEEK. Another example of the plastic is waxes, such as low-melting waxes. The plastic can also be in the initial form as a cross-linking reactive resin or as a duromer. Step b) involves heating, preferably to a temperature at which the plastic melts. For amorphous thermoplastics, this can be measured at the softening temperature (glass transition temperature T g ) and for semi-crystalline thermoplastics at the melting temperature (T m), whereby the heating should take place above these temperatures. The temperature lies accordingly in the typical primary forming temperature range of the thermoplastics and is preferably greater than 180 °C. c) The starting material itself can already be in fiber form. For example, plastic and fibers can be present as hybrid fibers (i.e. as semi-finished fiber products made of reinforcing fibers and at least one matrix fiber) which are not yet consolidated. Other starting materials can be thermoplastic unidirectional prepregs (UD prepregs or tapes) or fabric prepregs (so-called organic sheets) which are built up to form a laminate. These starting materials have in common that they are pressed under pressure and at a temperature which is higher than the melting or softening temperature of the matrix material and are then cooled in order to achieve the final strength and stiffness.

[0025] The plastic can preferably also be in the form of a fiber. Polymer fibers with a melting or softening temperature range between 50 and 400 °C are preferred, preferably thermoplastics, as already mentioned above. The polymer fibers can be semi-crystalline or amorphous. In addition to the initial form as a fiber, the matrix component can also be in the form of a polymer powder, melt layer, or film, for example.

[0026] Furthermore, composite structures consisting of at least two individual layers pre-impregnated with a matrix can be used as the starting material. However, there is no full-surface bond between the individual layers; instead, there is only a defined orientation of the fiber angles for reinforcement.

[0027] In the present invention, the starting material is placed on a carrier plate outside the device and heated. The carrier plate is located in a heating position in which a heating device is assigned to the carrier plate so that the carrier plate can be heated in the heating position. The carrier plate can already be heated when the starting material is placed on it or after placement. The carrier plate is preferably already heated before the starting material is placed, but can also be heated after the starting material has been placed. In the heated state, the carrier plate is transferred to the lower part of the device according to the invention with the plastic to be consolidated. This can be done, for example, using a handling device. The device comprises a coolable cooling plate and a heatable consolidation bell.The coolable cooling plate can have cooling channels through which a cooling medium can flow for cooling purposes. Therefore, a handling device can be provided for the device, with which the carrier plate can be moved between the heating position and the support surface of the lower part.

[0028] The carrier plate does not further define the contour or shape of the consolidated plastic with fibers. The actual contouring takes place either through upstream or downstream processes. The carrier plate is preferably used to produce only two-dimensional structures (i.e., sheets or films). Therefore, the carrier plate is preferably essentially planar, i.e., the support surface for the starting material has a flat surface (without curvature). The carrier plate can be designed as a circulating carrier and fed to a heating station in order to consolidate the same composite structure or, due to the geometric freedom, a different one according to the described scheme.

[0029] For process-related reasons, the contour of the deposited fiber composite structure can be raised or recessed in the carrier plate to fix the contour of the introduced unconsolidated plastic with fibers. For example, a recess in the carrier plate can preferably be in the range of 0.5 mm.

[0030] To prevent the heated support plate, which is placed on a support surface of the lower part, from slipping, it is advantageous for the lower part to have a recess in the area of ​​the support surface into which the support plate can be inserted – preferably in a form-fitting manner. Depending on the design, this recess can be inserted directly into the cooling plate or into supports.

[0031] Once the carrier plate is positioned on the base, the consolidating bell is positioned above the base and the device is closed. The consolidating bell is sealed airtight with a membrane, forming a cavity between the inner walls of the consolidating bell and the membrane. The consolidating bell is provided with the membrane on the side facing the base. The inner dimensions of the consolidating bell at least match the outer dimensions of the fiber-enclosed plastic to be consolidated; preferably, the carrier plate is completely covered. The consolidating bell covers the unsolidified, but already melted or activated plastic with fibers.

[0032] A heat generating device is assigned to the cavity in the consolidation bell. The cavity can be heated via the heat generating device. One or more radiant heaters can be provided for this purpose. The radiant heaters can be positioned directly in the cavity for direct heat input. The radiant heater is designed to generate radiant energy, particularly in the infrared spectral range. The heat generating device can directly heat the membrane and thus the underlying carrier plate. The irradiation is maintained for a predefined time, preferably in the range between 10 and 210 seconds. The irradiation ensures that the fiber composite structure maintains its working temperature throughout the entire irradiation time. Alternatively, the radiant heaters can be connected to the cavity via a heat pipe.

[0033] In order to achieve consolidation of plastic with fibers that do not have a uniform thickness, the consolidation bell has the membrane, which is pressed onto the plastic with fibers to be consolidated.

[0034] Because the membrane is clamped onto the consolidation bell, it can exert consolidation pressure upon being placed on the fiber-based plastic to be consolidated. Additionally, a pressure-generating device can be provided, which can be used to pressurize the cavity. Depending on the design, the pressure-generating device has two functions: Firstly, it can accelerate consolidation. Secondly, in designs with thermal decoupling elements between the carrier plate and cooling plate, the variable-length thermal decoupling elements can be compressed, so that after consolidation, the cooling plate and carrier plate are brought into direct contact by a relative movement to achieve cooling at the carrier plate.

[0035] The membrane can be, for example, an entropy-elastic material with high extensibility and reversible behavior, such as elastomers, or an energy-elastic material with low extensibility, such as metal membranes, or a purely energy-elastic material with plastic extensibility, such as polymer films. Combinations of these, such as an elastomer film combined with a polymer film, can also be used. The basic requirement is that the membrane can withstand the operating temperatures and can seal the consolidation bell gas-tight during a cycle. The membrane can be replaced after each cycle, after several cycles, or even remain permanently in the device.

[0036] During the irradiation time, as already explained, an overpressure is preferably additionally and simultaneously generated with a fluid in the consolidating bell. The consolidating pressure can be built up in the cavity of the consolidating bell. This pressure ranges from 0.5 to 200 bar above ambient pressure in the cavity and presses the membrane onto the carrier plate. Due to the duration of exposure to the working temperature and the overpressure, the plastic is consolidated with fibers. In the case of polymer matrix systems with fibers, powder, or film, this causes the matrix to flow and thus ensures good wetting of the reinforcing fibers, as well as the displacement of air. In the case of pre-impregnated laminates, the individual layers are welded together, and air is also displaced. With cross-linking matrix systems, a continuous cross-linking reaction is achieved, as well as the displacement of air.By applying a negative pressure (vacuum) to the lower part, the escape of air can be encouraged.

[0037] The process sequence is as follows: The carrier plate is heated to working temperature outside of the device. The working temperature is understood to be the temperature at which, in the subsequent consolidation process, temperatures are quickly reached at which the viscosity of the matrix component is sufficiently low to achieve good wetting properties or welding. The carrier plate can be heated outside the device by convection, induction, conduction / heat conduction or radiation. The carrier plate is preferably brought to the appropriate working temperature by heat conduction and infrared radiation. This is preferably above the melting or softening temperature of the thermoplastic matrix materials used, preferably in a temperature range between 50 and 400 °C. Specifically, the working temperature should at least be in the range of or above the softening or melting temperature of the polymer matrix orabove the activation temperature for curing a crosslinking matrix and thus within a temperature range of +50°C to +400°C. The carrier plate is preferably preheated to working temperature when the composite structure is deposited, resulting in melting of the matrix component and triggering a crosslinking reaction.

[0038] The heated carrier plate with the placed plastic with fibers is transferred into the device and placed on a support surface on the base. Transfer times should be kept as short as possible to maintain the temperature introduced into the carrier plate as much as possible. Transfer times are in the range of a few seconds. A handling device can be provided for this purpose.

[0039] In addition, the heat generator is in operation, which heats the membrane or heats the starting material through the membrane. The heat generator and the previously heated carrier plate ensure that the starting material maintains or reaches the appropriate temperature until the consolidation process is complete.

[0040] After the irradiation time has elapsed, the heat generation device is switched off or the power is reduced. The overpressure is maintained and acts on the fiber composite structure. In principle, the overpressure can also be increased or reduced. After the irradiation time has elapsed, contact is made with the cooling plate by changing the relative position of the carrier plate and the cooling plate, thus immediately starting the cooling process. When the cooling plate is in contact with the carrier plate, particularly good heat transfer is preferred. The larger the contact area between the cooling plate and the carrier plate, the faster the consolidated fiber composite structure cools down. When the fiber composite structure reaches a certain cooling temperature, the pressure can be released and the consolidation bell is opened again. The cooling temperature depends on the matrix system used and, for polymer matrix systems, should be at least 10 °C below the melting or curing temperature.softening temperature to achieve sufficient stability. After this cycle, the composite structure achieves its final material-specific physical properties, such as strength, elastic modulus, and density. Compared to the starting material, a compaction of the thickness structure is particularly noticeable. The relative position change from carrier plate to cooling plate is preferably reversible, thus repeating the process sequence from (a) to (g). The carrier plate is then moved out of the consolidation bell with the compacted, consolidated composite structure, where the composite structure is removed and can be subjected to further processing steps, such as forming.

[0041] Preferably, a cooling device is provided with which the cooling plate can be cooled. For this purpose, bores can be provided in the cooling device through which a cooling medium can be passed. The cooling plate can be cooled, for example, using water or other media. The cooling temperature is preferably at least 20°C below the operating temperature of the carrier plate.

[0042] The preferably cooled cooling plate is preferably not in direct contact with the carrier plate during step (e) and is therefore thermally separated from the carrier plate by an air gap.

[0043] Cooling the cooling plate enables faster cooling of the consolidated composite material. The simplest type of operation provides for the cooling device to continuously cool the cooling plate. However, to prevent the cooling plate from simultaneously cooling the heated carrier plate, a thermal decoupling device is provided between the carrier plate and the cooling plate in the region of the support surface. Thermal decoupling is understood to mean an interruption or reduction in heat conduction between the carrier plate and the cooling plate. For thermal decoupling, at least one preferably movable thermal decoupling element is preferably provided in the region of the support surface, which is designed such that the distance between the carrier plate and the cooling plate can be changed. The thermal decoupling element preferably has a lower thermal conductivity coefficient than the cooling plate.A relative change in position between the carrier plate, which rests on the thermal decoupling element, and the cooling plate until contact is established results in deactivation of the thermal decoupling. To achieve this, the thermal decoupling element can move, or the cooling plate or individual segments of the cooling plate can move.

[0044] A relative change in position of the carrier plate, which rests on the heat conduction decoupling element, and the cooling plate until contact is made between the carrier plate and the cooling plate, deactivates the heat conduction decoupling. To achieve this, the heat conduction decoupling element can be compressible. When pressure is generated with the pressure generation device in the consolidation bell, the carrier plate, which rests on the heat conduction decoupling element, is pressed against the cooling plate. By compressing the heat conduction decoupling element, the distance between the carrier plate and the cooling plate is reduced until the two are in direct contact. The heat conduction decoupling element can, for example, lie in a recess in the cooling plate of the lower part and reduce the longitudinal expansion. The heat conduction decoupling elements can be designed as supports, which can take on different shapes.Therefore, in one embodiment of the method, the pressure is additionally increased in step (f). Cooling of the carrier plate is achieved by compressing the heat conduction decoupling element.

[0045] Heat conduction decoupling elements can also be telescopic, for example. In this case, the heat conduction decoupling element is additionally moved in step (f) to achieve thermal decoupling between the carrier plate and the cooling plate.

[0046] The heat conduction decoupling can, for example, comprise supports of variable length. These supports of variable length can be compressible. The heat generation device can then be deactivated, for example, after a certain period of time (selectably between 10 and 300 seconds), and the pressure in the cavity of the consolidation bell can be increased relative to the consolidation pressure. This pressure increase compresses the heat conduction decoupling elements of variable length, so that a relative change in position causes the hot carrier plate to rest directly on the cooling plate and cool down quickly. In this embodiment, the heat conduction decoupling elements of variable length can, for example, comprise spring elements and / or compressible elements (e.g., plastics or rubber with empty spaces or the like). The heat conduction decoupling elements have a thermal conduction coefficient that is lower than the thermal conduction coefficient of the cooling plate.The length-adjustable heat conduction decoupling elements decouple the carrier plate from the cooling plate with regard to heat conduction due to their lower thermal conduction coefficient.

[0047] Preferably, several thermal decoupling elements are provided. In a further embodiment, thermal decoupling is activated or deactivated by a relative position change by advancing or moving the cooling plate. The thermally insulating thermal decoupling elements are stationary, and during the consolidation process, the cooling plate has no contact with the carrier plate to prevent heat dissipation as best as possible. After the consolidation process is complete, the pressure in the consolidation bell remains greater than the ambient pressure, and the cooling plate is moved toward the hot carrier plate. This deactivates the thermal decoupling and initiates the cooling process.

[0048] The carrier plate is preferably a two-dimensional plate with a plate thickness of preferably 0.5 to 15 mm, particularly preferably between 1 and 4.5 mm. Steel is preferably used as the plate material, although any material with sufficient temperature resistance to the operating temperature can be used. If necessary, the carrier plate can be coated with a non-stick coating on the side facing the plastic with fibers.

[0049] The device preferably has a pressure increasing device with which the pressure in the cavity can be changed.

[0050] DETAILED DESCRIPTION OF THE INVENTION

[0051] Further advantages and details of the invention are explained with reference to the figures and the description of the figures. Identical components in different figures and embodiments are provided with the same reference numerals; therefore, for reasons of clarity, a complete description of all reference numerals is not provided for each figure. In this regard, reference is made to the description of other embodiments.

[0052] They show:

[0053] Fig. 1a, 1b a device according to the invention in the open state (Fig. 1a) and the heating position (Fig. 1b).

[0054] Fig. 2a, 2b the device from Fig. 1a and 1b in closed state in two operating states.

[0055] Fig. 3a, 3b the carrier plate with lower part of a second embodiment variant.

[0056] Fig. 4a, 4b show the carrier plate with lower part of a third embodiment. In Fig. 1a, a device 1 according to the invention for consolidating a plastic 2 with fibers is shown in the open position. In addition to the lower part 6, the device 1 comprises a consolidation bell 4 (upper part), with which a carrier plate 10, which is arranged on a support surface 12 of the lower part 6, can be covered. The consolidation bell 4 has a membrane 5 on the side facing the lower part 6. A cavity 8 is formed between the inner wall 7 of the consolidation bell 4 and the membrane 5. Furthermore, a heat generating device 9 in the form of two heat radiators is provided, with which the cavity 8 can be heated. The heat generating device 9 is arranged in the cavity 8.

[0057] The cooling plate 3, which has holes 14 for cooling the cooling plate 3, can be seen on the lower part 6. The carrier plate 10 rests on the support surface 12, which is formed in a recess 16 in the lower part 6 in the area of ​​the cooling plate 3.

[0058] The plastic 2 with fibers to be consolidated is placed on the carrier plate 10. In the example of Fig. 1a, the carrier plate 10 is already located in the support surface 12. However, at the beginning of the process, the carrier plate 10 is in a heating position 17 arranged outside the device 1, wherein the plastic 2 with fibers to be consolidated is first placed on the carrier plate 10 in the heating position 17 (Fig. 1b). The plastic 2 to be consolidated, which is placed on the carrier plate 10 in heating position 17, is heated, and then the carrier plate 10 with the plastic 2 placed thereon is removably positioned in the support surface 12 of the lower part 6. The heating of the plastic 2 with fibers to be consolidated can take place by preheating the carrier plate 10 and / or by heating the carrier plate 10 with the plastic 2 with fibers arranged thereon. For this purpose, a heating device 13 is provided, which is assigned to the carrier plate 10.

[0059] In order to achieve consolidation of plastic 2 with fibers that do not have a uniform thickness, the consolidation bell 4 has the membrane 5, which is pressed onto the plastic 2 with fibers to be consolidated after the carrier plate 10 with the plastic 2 including fibers has been positioned in the support surface 12 of the lower part 6.

[0060] The lower part 6 has a recess 16 in the area of ​​the support surface 12, into which the carrier plate 10 is inserted and sits in a form-fitting manner, thus preventing slippage. The cooling plate 3 can be cooled via a cooling device. For this purpose, bores 14 are provided through which a cooling medium can be passed.

[0061] Furthermore, in the area of ​​the support surface 12, heat conduction decoupling elements 15 are provided between the support plate 10 and the cooling plate 3. The heat conduction decoupling elements 15 are movable and designed such that the distance between the support plate 10 and the cooling plate 3 can be changed. The heat conduction decoupling elements 15 of Fig. 1a are compressible.

[0062] Figs. 1a and 2a show the non-compressed heat conduction decoupling elements 15. These are made of a material with low thermal conductivity and thus decouple the cooling plate 3 from the carrier plate 10 with regard to heat conduction. Fig. 2a shows the plastic 2 with fibers, which is covered by the membrane 5, wherein the heat generating device 9 is active and heats the plastic 2 with fibers. Likewise, a pressure p acts in the cavity 8 to compress the plastic 2 with fibers. A pressure generating device 20 is provided for pressure generation. The pressure generating device 20 is only shown in Fig. 1a. In the other embodiments and figures, the pressure generating device 20 is omitted for reasons of clarity.

[0063] If the pressure in the cavity 8 is further increased (Fig. 2b), the heat conduction decoupling elements 15 are compressed and the cooling plate 3 comes into direct contact with the carrier plate 10. This enables heat conduction, and the cooled cooling plate 3 can thus cool the carrier plate 10.

[0064] Alternative embodiments are shown schematically in Figs. 3a, 3b, 4a and 4b. The embodiment of Figs. 3a and 3b differs from the embodiment of Figs. 1a to 2b in that the heat conduction decoupling between the carrier plate 10 and the cooling plate 3 is achieved by immobile, stationary heat conduction decoupling elements 15. In Fig. 3a, the plastic 2 with fibers is again covered with the membrane 5 of the consolidation bell 4, the heat generating device 9 is active and the plastic 2 with fibers is thus heated. A pressure p in the cavity 8 compresses the plastic 2 with fibers. Instead of a further increase in pressure in the cavity 8 as in the example in Fig. 2b, the cooling plate 3 is moved upwards here (Fig. 3b) so that the cooling plate 3 comes into direct contact with the carrier plate 10 in order to enable heat conduction for cooling the carrier plate 10 through the cooling plate 3.

[0065] 4a and 4b, a heat conduction decoupling element 15 in the form of a compressible insert is provided between the carrier plate 10 and the cooling plate 3. As in the example in Fig. 2a and 2b, the plastic 2 fibers are covered by the membrane 5 and the heat generating device 9 is active. A pressure p in the cavity 8 compresses the plastic 2 with fibers, whereby a further increase in pressure occurs in the cavity 8 for cooling (Fig. 4b), so that the insert is compressed. The cooling plate 3 comes into direct contact with the carrier plate 10 at contact surfaces not shown in order to enable heat conduction for cooling the carrier plate 10 through the cooling plate 3. In this embodiment, the heat conduction decoupling between the carrier plate 10 and the cooling plate 3 is again achieved via a compressible heat conduction decoupling element 15, namely a compressible insert.The compressible insert is compressed by applying pressure in the cavity, so that the cooling plate 3 comes into contact with the carrier plate 10. The thermal decoupling element 15 has a lower thermal conductivity coefficient than the cooling plate 3.

[0066] In all examples, cooling of the support plate 10 is achieved by a relative change in the position of the cooling plate 3. The support plate 10 rests on one or more heat conduction decoupling elements 15. The movement of the heat conduction decoupling elements 15 can be achieved actively by a stroke (e.g., hydraulically or electrically driven) or passively by compression of the heat conduction decoupling elements 15. The relative change in the position of the heat conduction decoupling elements 15 is preferably reversible.

[0067] In an embodiment not shown, it is provided that the heat conduction decoupling element 15 is designed, for example, as a mat and has openings through which movable contact elements protrude, which are initially not in contact with the carrier plate 10 and are brought into contact with the carrier plate 10 for cooling.

Claims

CLAIMS 1. A method for consolidating a plastic (2) with fibers, comprising the steps: (a) Placing the plastic (2) to be consolidated with fibers on a carrier plate (10), (b) heating the plastic (2) with fibers on the carrier plate (10), (c) Placing the carrier plate (10) with the heated plastic (2) with fibers on a base (6), (d) Covering the lower part (6) including the support plate (10) with a consolidation bell (4), wherein the consolidating bell (4) has a membrane on the side facing the lower part (6) (5) which defines a cavity (8), wherein the membrane (5) rests on the heated plastic on the carrier plate (10), (e) heating the membrane (5) and applying an overpressure in the cavity (8), (f) cooling the carrier plate (10); (g) Opening the consolidation bell (4) and removing the consolidated plastic with continuous fibers.

2. The method according to claim 1, characterized in that in step (f) the carrier plate (10) is cooled by relative positional change and contacting of the carrier plate (10) with a cooling plate (3).

3. Method according to claim 1 or claim 2, characterized in that the plastic is a thermoplastic.

4. Device (1) for consolidating a plastic (2) with fibers, wherein the device (1) has a lower part (6) with a cooling plate (3), wherein the lower part (6) can be closed with a consolidation bell (4), wherein the consolidation bell (4) has a membrane (5) on the side facing the lower part (6), wherein a cavity (8) is formed between the inner wall (7) of the consolidation bell (4) and the membrane (5), wherein a heat generating device (9) is provided with which the cavity (8) can be heated, characterized in that a carrier plate (10) is provided for the plastic (2) with fibers, wherein the lower part (6) has a support surface (12) for the detachable reception of the carrier plate (10), wherein the carrier plate (10) is assigned a heating device (13) with which the carrier plate (10) can be heated in a heating position (17).

5. Device according to claim 4, characterized in that the lower part (6) has a recess (16) in the region of the support surface (12) into which the carrier plate (10) can be partially inserted.

6. Device according to claim 4 or claim 5, characterized in that a cooling device is provided with which the cooling plate (3) can be cooled.

7. Device according to one of claims 4 to 6, characterized in that in the region of the support surface (12) at least one preferably movable heat conduction decoupling element (15) is provided, which is designed such that the distance between the support plate (10) and the cooling plate (3) is variable.

8. Device according to claim 7, characterized in that the at least one heat conduction decoupling element (15) is compressible.

9. Device according to claim 7 or claim 8, characterized in that the at least one heat conduction decoupling element (15) is telescopic between the support plate (10) and the cooling plate (3).

10. Device according to one of claims 4 to 6, characterized in that in the region of the support surface (12) at least one preferably immovable, stationary heat conduction decoupling element (15) is provided, which is designed such that the distance between the support plate (10) and the cooling plate (3) can be changed by moving the cooling plate (3).

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