Structural component made of thermoplastic plastic material for a motor vehicle, motor vehicle having a structural component and method for producing a structural component

Abstract

The invention relates to a flat structural component (10), in particular an underbody protection element (10), for a motor vehicle (41), in particular an electric vehicle, comprising a flat core element (32) made of a first thermoplastic plastic material, at least one lower covering layer and at least one upper covering layer (34a, 34b) made of a second fiber-reinforced thermoplastic plastic material, wherein the covering layers (34a, 34b) are formed and connected to the core element (32) in a material-fitting manner. The invention also relates to a motor vehicle having such a structural component, in particular an underbody protection element, and a method for producing such a structural component, in particular an underbody protection element.

Description

Technical Field

[0001] The present invention relates to a flat structural component (especially an underbody protection element or a partition wall element or a covering element) made of a thermoplastic plastic material for a motor vehicle (especially an electric vehicle), a motor vehicle having such a structural component (especially an underbody protection element), and a method for producing such a structural component (especially an underbody protection element). Background Art

[0002] Hitherto, flat structural components for motor vehicles, such as underbody protection elements, have usually been produced from metal components, such as aluminum sheets, etc. Such metal sheets can also be arranged in a multilayer structure of the structural component, such as the underbody protection element.

[0003] For example, reference may be made to DE 10 2017 006753 A1, DE 10 2015 103 902 A1 and DE 10 2019 104 883 A1 for underbody protection elements or floor protection plates. Reference may also be made to US 2013 / 0280469 A1 for a structural member designed as a storage box for the interior of a motor vehicle.

[0004] As an example of a structural component under discussion here, underbody protection elements are used in particular to protect pressure vessels or tanks and / or electrical components (e.g. high-voltage batteries etc.), in particular when driving over road irregularities (e.g. railroad ties, road bollards, curbstones etc.). Underbody protection elements made at least partially of metal or sheet metal have the disadvantage that they are permanently deformed when driving over road irregularities, i.e. dents, kinks etc. often remain in the underbody protection element. Furthermore, underbody protection elements containing metal are heavy, which is disadvantageous to the overall efficiency of the motor vehicle.

[0005] This also applies analogously to structural components such as partitions or covering elements, which in motor vehicles, for example, serve as covers for high-voltage batteries or as partitions between vehicle components. Even in such structural components, which do not necessarily form the outer boundary of a motor vehicle, a low weight combined with a high stability is very important. Summary of the invention

[0006] The object of the present invention is to propose a structural component, in particular an underbody protection element, and a method for producing the structural component, in order to avoid the above-mentioned disadvantages.

[0007] This object is achieved by a structural component (for example an underbody protection element) having the following features, a motor vehicle (in particular an electric vehicle) having the following features, and a method having the following features. Advantageous embodiments with effective developments are also given below.

[0008] Therefore, a structural component, in particular an underbody protection element, for a motor vehicle, in particular an electric vehicle, is proposed, which has a flat core element made of a first thermoplastic plastic material, and at least one lower covering layer and at least one upper covering layer made of a second fiber-reinforced thermoplastic plastic material, wherein the covering layers are modified and materially connected to the core element, and the core element is made of an injection-molded blank accommodated between the covering layers or of an extruded blank accommodated between the covering layers.

[0009] By using thermoplastic materials, structural components can be produced cost-effectively and are lightweight. The fiber-reinforced cover layer ensures, in particular, sufficient stability of the structural component. The use of thermoplastic materials also has the advantage that the structural component is more elastic than structural components containing metal. Accordingly, in the case of structural components made of thermoplastic materials, for example in the form of underbody protection elements, no plastic deformations (for example dents or kinks) generally occur when the underbody protection element comes into contact with ground irregularities.

[0010] Since the core element is produced from an injection-molded blank or an extruded blank, the core element, which is initially present as an unshaped plastic material blank, is shaped while being reshaped together with the covering layer.

[0011] In order to further improve the stability of the structural component, the first thermoplastic plastic material can be fiber-reinforced. Here, the first thermoplastic plastic material can contain long fibers made of glass, wherein the length of the glass fibers is preferably about 1mm to 50mm, especially 1mm to 10mm.

[0012] The second thermoplastic material can contain endless fibers, which can especially contain glass fibers and / or carbon fibers and / or aramid fibers and / or natural fibers. Here, the cover layer can be made of a fiber semi-finished product, especially an organic sheet and / or at least one UD tape.

[0013] In order to achieve an optimal material-fit connection during the remodeling, the first plastic material and the second plastic material can be compatible with each other in terms of their material properties. In this case, especially in the case of fiber-reinforced (first and second) plastic materials, the corresponding plastic matrix can be made of the same material, especially made of polypropylene (PP) or polyamide (PA).

[0014] The structural component can have at least one raised section formed jointly in the core element and the covering layer. In this case, the raised region can have a through-opening adapted to receive a connecting element provided for fastening the structural component, in particular the underbody protection element, to the vehicle body. Such a raised section can also be referred to as a disk-shaped section. The raised section can have a substantially flat raised surface which, in the mounted state of the structural component, in particular the underbody protection element, bears against the vehicle body component.

[0015] The structural component can have at least one rib-shaped reinforcement section, wherein the reinforcement section is formed from the first plastic material and wherein the reinforcement section protrudes beyond the cover layer. Such a reinforcement section increases the stability of the structural component, in particular the underbody protection element. The reinforcement section can also be formed on one of the cover layers.

[0016] The reinforcement sections can merge into the raised sections, wherein at least one reinforcement section is formed in particular between two raised sections. In other words, the reinforcement sections can form connecting ribs between adjacent raised sections. Furthermore, the reinforcement sections can have essentially flat rib surfaces which merge into the raised surfaces, so that the structural component, in particular the underbody protection element, rests against the vehicle body in the installed state via the raised surfaces and the rib surfaces.

[0017] The structural component can have at least one edge region which is formed exclusively from the first plastic material and is formed integrally with the core element accommodated between the covering layers. In this case, a plurality of through-openings can be provided in the edge region, which are adapted to accommodate connecting elements which are provided for fastening the structural component, in particular the underbody protection element, to the vehicle body. The edge regions can also be designed in such a way that they form a frame which surrounds or encloses the covering layers.

[0018] A motor vehicle, in particular an electric vehicle, has a body and can have a structural component, in particular an underbody protection element, fastened to the body. The structural component, which is designed as an underbody protection element, can be arranged below an energy storage device, in particular below a high-voltage battery or a pressure tank. As a result, sensitive components such as a high-voltage battery or a pressure tank (for example for gas) can be particularly well protected.

[0019] A method for producing a structural component, in particular an underbody protection element, comprising the following steps:

[0020] introducing a first thermoplastic plastic material provided as an unshaped, in particular injection-moldable or extrudable plastic material blank between a lower cover layer and an upper cover layer made of a second fiber-reinforced thermoplastic plastic material;

[0021] A first plastic material is molded together with the covering layers, wherein during the molding process the first plastic material is distributed between the covering layers in such a way that after the molding it forms a core element which is covered at least regionally on both sides by the covering layers.

[0022] In short, an unformed or non-shaped first plastic blank is placed between covering layers provided as a semi-finished product, and then the initially unformed first plastic blank is formed between the covering layers under pressure so that after the modification, the formed core element is connected to the covering layer material in a fitting manner and essentially has the desired final shape or design of the bottom protection element.

[0023] In the method, long fibers made of glass are added to the first thermoplastic material before it is introduced between the cover layers. Thus, a (glass) fiber-reinforced first plastic blank is provided before the modification, and then the first plastic blank containing (glass) fibers is formed into a core element.

[0024] The introduction of the first plastic material can be carried out by an extrusion process, wherein a plastic blank contained between the covering layers is extruded by means of a pressure effect. In other words, a lower covering layer and an upper covering layer can be provided in or on a corresponding pressing tool, wherein a blank of the first plastic material (for example in the form of an unshaped or unshaped block) is placed between these covering layers. By closing the pressing tool, the initially unshaped first plastic material is extruded between the two covering layers, thereby forming a core element, which is connected to the covering layer material in a matching manner, wherein the covering layer is also reshaped due to the pressure effect.

[0025] The introduction of the first plastic material can also be carried out by an injection molding process, in which an unshaped or non-shaped plastic material is injected between the covering layers. In the injection molding process, the first plastic material can be physically or chemically foamed during or after the injection between the covering layers. By foaming the first plastic material, a foamed, shaped core element can be produced between the covering layers. By foaming the first plastic material, its viscosity can be reduced, which simplifies processing or injection molding. In addition, lightweighting can be achieved by foaming.

[0026] The cover layer can in particular be provided as a fiber-reinforced semi-finished product, for example in the form of an organosheet and / or at least one layer of UD tape.

[0027] In this method, foaming can take place after the injection of the first plastic material by expansion foaming, wherein the associated pressing or casting tool elements, in particular tool halves or tool parts, are moved away from one another after the injection of the first plastic material.

[0028] Here, relevant pressing or casting tool elements can be separated from each other by about 0.5mm to 10mm, especially 1mm to 5mm. Here, the distance that tool elements or tool halves are separated from each other can be larger or smaller, which depends in particular on their movement direction relative to each other and their design.

[0029] In the modified core element, the volume fraction of the cavities produced during the expansion and foaming process can be about 10% to 50% of the volume of the solid plastic material. However, the proportion of the cavity volume can also be greater than the proportion of the solid plastic material volume, in particular the cavity volume can also be two or three times (200% to 300%). The tool elements can also be kept away from each other for a certain period of time, so as to leave enough time for the core material to foam by expansion, including a period of time for cooling and hardening the foam structure if necessary.

[0030] In the method, structural elements protruding from the relevant covering layer, in particular reinforcing elements or sealing elements, can be applied to at least one of the covering layers in a foamed or non-foamed manner by means of an injection molding process.

[0031] In this case, the structural elements applied to the respective covering layer can be produced from the same plastic material as the core element or from a different plastic material therefrom.

[0032] Furthermore, glass fibers or minerals or elastic materials may be added to the plastic material of the applied structural element in a different proportion than that added to the first plastic material of the core element.

[0033] Thus, after or possibly during the so-called shaping of the core element (together with the shaping of the covering layer), additional structures such as reinforcing elements or ribs or sealing elements or protruding edge sections etc. can be applied by injection molding. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Further advantages and details of the invention are given by the following description of embodiments with reference to the accompanying drawings, in which:

[0035] Figure 1 shows a top view of an embodiment of a structural member implemented as an underbody protection element;

[0036] Figure 2 Shows Figure 1 A perspective view of a bottom protection element;

[0037] Figure 3 In the sub-figures A) to D) it is shown that in particular along Figure 1 An enlarged cross-sectional view of section line III-III;

[0038] Figure 4In sub-figures A) and B) are shown respectively Figure 2 Enlarged views of fragments IVA and IVB;

[0039] Figure 5 Shows Figure 3 A simplified sectional view of an underbody protection element in combination with a purely schematically illustrated component of a motor vehicle;

[0040] Figure 6 A schematic diagram showing a method for manufacturing an underbody protection element;

[0041] Figure 7 The sub-figures A) and B or C) and D) respectively show schematically and in simplified form the structural components in the mold during the expansion foaming process. DETAILED DESCRIPTION

[0042] Figure 1 The top view schematically and simplified shows an embodiment as a structural component of an underbody protection element 10. In the state in which the underbody protection element 10 is mounted on a motor vehicle (not shown here), the upper side 12 of the underbody protection element 10 visible in the figure faces the body of the motor vehicle.

[0043] First, refer to Figure 1 and Figure 2 A structural component implemented as an underbody protection element is described.

[0044] The underbody protection element 10 has a central region 14 in which the underbody protection element 10 is reinforced. In this example, the central region 14 is surrounded by a peripheral edge region 16. A plurality of raised regions 18 are formed in the central region 14. The raised regions 18 can each have a through-opening 20. A connecting element (not shown here) can be passed through such a through-opening 20, which connecting element is provided for fastening the underbody protection element 10 to the vehicle body. Figure 1 and Figure 2 As can be seen from the illustration of , the raised areas 18 can have different sizes, in particular different diameters. In addition, these raised areas can be arranged at different positions of the underbody protection element 10 or its central area 14 .

[0045] Furthermore, the underbody protection element 10 can have a plurality of rib-like reinforcement sections 22 . In the example shown, the reinforcement sections 22 extend in the longitudinal direction Y. In particular, they each extend between adjacent raised areas 18 .

[0046] Especially from Figure 2It can be seen in FIG. 1 that the central region 14 is designed as a kind of groove. Here, the groove is delimited by an inclined and / or stepped wall section 24. In this example, the wall section 24 forms a transition from the central region 14 to the surrounding edge region 16. Further through-openings 26 can be arranged in this edge region, which are used to receive connecting elements for fastening the underbody protection device 10 to the motor vehicle. Purely by way of example and for a better understanding, in FIG. Figure 2 1 shows an underbody protection element 10 , wherein a hatched central region 14 is shown in the lower illustration.

[0047] exist Figure 3 In the figure, sub-figures A) to D) show the corresponding Figure 1 A cross-sectional view of the section line III-III. Among them, Figure 3 A shows the entire bottom protection element 10 . Figure 3 B to Figure 3 D shows the corresponding Figure 3 An enlarged fragment of the circled area B to D of A. Figure 3 A to Figure 3 The cross-sectional view D illustrates the configuration of the bottom protection element 10 .

[0048] Figure 3 A shows the entire width (in the X direction) of the bottom protection element 10. Figure 1 and Figure 2 As already described, the edge region 16, the central region 14, the raised region 18 with the through-opening 20, the plurality of reinforcement sections 22 and the inclined or / and stepped wall sections 24 can be seen. In the selected illustration, the upper side 12 of the underbody protection element 10 points downward. The underside 28 of the underbody protection element 10 points upward in the illustration. In the state installed on the motor vehicle, the underside 28 of the underbody protection element 10 faces the foundation or the ground on which the motor vehicle is located.

[0049] Figure 3 B shows by way of example the raised area 18 and the through-opening 20 formed therein. A sleeve 30, in particular a metal sleeve, can be inserted into the through-opening 20. Figure 3 B to Figure 3 The internal structure of the bottom protection element 10 can also be seen in the cross-sectional view D.

[0050] The underbody protection element 10 can have a core element 32, in particular in its central region 14. The core element 32 can be arranged between an upper cover layer 34a and a lower cover layer 34b.

[0051] In this case, the core element 32 can be made of a first thermoplastic plastic material. The first plastic material of the core element 32 can be fiber-reinforced and can contain, for example, long glass fibers having a length of approximately 1 mm to 50 mm, in particular 1 mm to 10 mm.

[0052] The cover layers 34a, 34b can be made of a second fiber-reinforced thermoplastic material. Here, the second thermoplastic material can contain endless fibers, especially glass fibers and / or carbon fibers and / or aramid fibers and / or natural fibers. The cover layers 34a, 34b can be made of a fiber semi-finished product, especially an organic sheet and / or at least one layer of UD-Tape.

[0053] The first plastic material of the core element 32 and the second plastic material of the covering layers 34a, 34b can be compatible with each other in terms of their material properties. Here, especially when fiber-reinforced plastic material is used for the core element 32 and the covering layers 34a, 34b, the corresponding plastic matrix can be made of the same material. Thermoplastic polypropylene (PP) or polyamide (PA) are particularly suitable as plastic material. Of course, other thermoplastics can also be used, and it is also conceivable that suitable polymer blends or polymer alloys are used for the core element 32 and / or the covering layers 34a, 34b.

[0054] from Figure 3 C shows that in the region of the rib-shaped reinforcement sections 22, the cover layers 34a, 34b are modified together with the core element 32. The individual reinforcement sections 22 or reinforcement ribs protruding from the (upper) cover layer 34a can be made of the same plastic material as the core element 32.

[0055] from Figure 3 As can be seen from D, the covering layers 34a, 34b end in the transition region from the central region 14 to the edge region 16, in particular in the region of the inclined or / and stepped wall section 24. In other words, the edge region 16 and / or the wall section 24 are formed from the first thermoplastic material. They are therefore made of the same material as the core element 32 of the underbody protection element 10. Figure 3 D shows that the core element 32 and the wall section 24 and / or the edge region 16 are formed integrally with each other. Figure 3 An optional sealing element 23 is shown in D. The sealing element 23 may be made of the same plastic material as the core element 32. Alternatively, the sealing element 23 may be made of the same basic plastic but contain other additions, such as fibers, minerals or elastomeric components.

[0056] Combination Figures 1 to 3From this point of view, it can also be said that the cover layers 34a, 34b and the core element 32 are formed in the central region 14 of the underbody protection element 10. Furthermore, the cover layers 34a, 34b are jointly formed with the core element 32 and are materially connected.

[0057] Figure 4 In sub-figures A) and B) it is shown Figure 2 1 and 10. The two figures show that the reinforcement section 22 or the reinforcement ribs merge into the raised area 18. The raised section 18 can have a substantially planar raised surface 36, which in the installed state of the underbody protection element 10 rests against the vehicle body component. The reinforcement section 22 can have substantially planar rib surfaces 38, which merge into the raised surface 36, so that the underbody protection element rests against the vehicle body in the installed state via the raised surface 36 and the rib surfaces 38. It should be pointed out that the rib surface 38 does not necessarily have to rest over its entire surface, but its support or abutment on the vehicle body component can also be limited to the region or periphery where the raised area 18 is formed.

[0058] exist Figure 4 A and Figure 4 In the example shown in B, the corresponding rib surfaces 38 of the central reinforcement section 22 merge into the raised surface 36. The reinforcement sections arranged to the left or right of the central reinforcement section 22 respectively have rib surfaces 38 which are designed to be continuous in the region of the raised area 18 as well.

[0059] Figure 5 A purely schematic and simplified cross-sectional view of an underbody protection element 10 in the installed position is shown. The underbody protection element 10 faces with its upper side 12 a body component 40 of a motor vehicle 41 which is indicated only by a dashed rectangle. In the example shown, the central region 14 of the underbody protection element is arranged below a high-voltage battery 42 which is shown simplified as a rectangular block and without further details. The high-voltage battery 42 is connected to the body 40 of the motor vehicle via a support structure 44 (e.g. a trough-shaped floor element or the like). As can be seen from the illustration, the raised region 18 (or raised regions 18) of the underbody protection element 10 abuts against the lower side of the support structure 44 and is connected thereto (e.g. screwed). The underbody protection element 10 is arranged on the motor vehicle in such a way that, in particular, the high-voltage battery 42 is protected from impacts from below.

[0060] The underbody protection element 10 is therefore particularly adapted for protecting a high-voltage battery 42 of an electric vehicle. Alternatively, the underbody protection element 10 can also be used for protecting a pressure tank or pressure container (eg a CNG tank or the like).

[0061] The structural component used as underbody protection element 10 in the above-described embodiment can also be used for other purposes. In particular, the structural component can be used as a partition wall or as a covering element or as a cover plate in a motor vehicle or a motor vehicle component. For example, it is conceivable to use the structural component in the form of a cover plate in the housing of a high-voltage battery. Furthermore, the structural component in the form of a partition wall can be used, for example, to separate different areas or compartments of a motor vehicle from one another, for example to separate a luggage space from a passenger space or an engine space from a passenger space, etc.

[0062] As referenced above Figure 3 As already mentioned, the structural component embodied as an underbody protection element is formed by a core element 32 and cover layers 34a, 34b. Here, the structural component, in particular as an underbody protection element 10, can be produced according to the method described below, which is Figure 6 It is shown as a schematic diagram in FIG.

[0063] In the method 500 for producing a structural component, in particular an underbody protection element 10, according to step S501, a first thermoplastic plastic material is provided as an unshaped, in particular injection-moldable or extrudable plastic material blank. According to step S502, the plastic material blank is introduced between a lower cover layer and an upper cover layer 34a, 34b made of a second fiber-reinforced thermoplastic plastic material. In step S503, the first plastic material and the cover layers 34a, 34b are jointly reshaped, wherein during the joint reshaping, the first plastic material is distributed between the cover layers 34a, 34b, so that after the reshaping, the first plastic material forms a core element 32, which is covered at least regionally on both sides by the cover layers 34a, 34b.

[0064] According to optional step S504, long fibers made of glass can be added to the first thermoplastic plastic material before it is introduced between the cover layers 34a, 34b. This step S504 can also be performed before step S501, so that the provided first plastic material blank already contains corresponding glass fibers.

[0065] The introduction (S503) of the first plastic material may be performed by an extrusion process S503a, wherein a plastic blank contained between the cover layers 34a, 34b is extruded by means of pressure.

[0066] Alternatively or additionally, the introduction of the first plastic material ( S503 ) may be performed by an injection molding process S503 b , wherein the plastic material is injected between the cover layers 34 a , 34 b .

[0067] In the injection molding process according to step S503b, the first plastic material may be physically foamed or chemically foamed during or after being injected between the cover layers 34a, 34b.

[0068] In method 500, according to step S505, foaming can be performed by expansion foaming after the first plastic material is injected. Here, expansion foaming is a physical foaming. In the case of such expansion foaming, the relevant pressing or casting tool elements (especially tool halves or tool parts) move away from each other after the first plastic material is injected (S506). In step S506, the relevant pressing or casting tool elements can be moved away from each other by about 0.5 mm to 10 mm, especially 1 mm to 5 mm. After the expansion foaming (S505, S506) is performed, in the core element after the modification is completed, the volume fraction of the voids generated during the expansion foaming process can be about 10% to 50% of the volume of the solid plastic material.

[0069] In the method 500, according to step S507, structural elements protruding from the relevant cover layers 34a, 34b, in particular the reinforcing elements 22 ( Figure 3 C. Figure 4 ) or sealing element 23 ( Figure 3 D) is applied to at least one of the covering layers 34a, 34b. Here, the structural element applied to the relevant covering layer 34a, 34b, in particular the reinforcing element 22, can be made of the same plastic material as the core element 32 or of a different plastic material therefrom. In this method, the applied structural element (for example, the reinforcing element 22, see Figure 3 C. Figure 4 ) is added to the plastic material of the core element 32 in a proportion different from that added to the first plastic material of the core element 32.

[0070] By foaming the first plastic material, a foamed, shaped core element can be produced between the cover layers. If the above-mentioned expansion foaming (S505, S506) is not used, the viscosity of the first plastic material can be reduced by foaming, thereby simplifying processing or injection molding.

[0071] Any type of foaming will save weight.

[0072] In the step S503 of introducing the first plastic material, a first plastic material blank, which is initially unshaped, is reshaped together with the covering layer, which is provided, for example, as a UD-Tape or an organic sheet. Here, the first plastic blank is so-called shaped (urgeformt), that is, it is brought from a substantially unshaped state into a final shape, which is achieved in particular by introducing the material under pressure. Of course, in order to shape the first plastic material and then form the core element 32 therefrom, a corresponding molding tool or / and pressing tool or / and injection molding tool is used, which is capable of carrying out the above-mentioned extrusion molding process or injection molding process using the covering layers 34a, 34b.

[0073] In other words, an unmolded first plastic blank is placed between the covering layers 34a, 34b provided as a semi-finished product, and then the first plastic blank is molded between the covering layers 34a, 34b under pressure, so that after the modification, the molded core element 32 is materially connected to the covering layers 34a, 34b and basically has the desired final shape or design of the bottom protection element 10.

[0074] As already pointed out above with reference to step S507, the extrusion molding process and the injection molding process can also be used in combination, which can be done, for example, in Figure 3 C. While the first plastic material for the core element 32 has been distributed between the covering layers 34a, 34b by means of extrusion and the core element and the covering layers 34a, 34b have been jointly molded and materially connected to one another, the reinforcing section 22 or reinforcing ribs made of the same plastic material as the core element 32 can be injection molded onto the upper covering layer 34a.

[0075] Alternatively, it is also conceivable that the relevant covering layer 34a is split in the region of the reinforcement section 22 or a predetermined breaking point or slit may have been introduced in advance so that the first plastic material can escape during the extrusion process. In this case, the reinforcement section 22 will not be arranged on the covering layer 34a, but will be connected integrally to the core element 32.

[0076] Refer to the following Figure 7 The above-mentioned steps S505 and S506 of the method related to expansion and foaming are explained in more detail.

[0077] exist Figure 7 In the figure, sub-figures A) and C) respectively show the state where the tool elements or tool halves 50a, 50b are pressed against each other. Two covering layers 34a, 34b are arranged in the cavity or mold space formed by the tool elements 50a, 50b, and the first plastic material of the core element 32 has been injected between the covering layers 34a, 34b, as described above with reference to step S503b ( Figure 6 ) as already explained.

[0078] exist Figure 7 , sub-figures B) and D) respectively show a state in which the tool elements or tool halves 50a, 50b have been moved away from each other, which is indicated by the corresponding double arrow 52. By moving the tool halves 50a, 50b relative to each other, the injected plastic material of the core element 32 can expand. In this case, bubbles or cavities are formed in the core element 32. The (expanded) foamed state of the core element 32 is shown in FIG. Figure 7 B) and Figure 7 D) is shown in a simplified manner by vertically intersecting hatching.

[0079] from Figure 7 It can be seen that the distance AB formed between the tool elements or tool halves 50a, 50b when moving away from each other can be smaller ( Figure 7 B) or larger ( Figure 7 D).

[0080] exist Figure 7 In the A / B example, the tool halves 50a, 50b may, for example, only move slightly away from each other (eg, in the order of 0.5 mm to 2 mm) so that little or no plastic material escapes into the resulting gap between the tool halves 50a, 50b.

[0081] exist Figure 7 In the example of C / D, the tool lower half 50b is implemented as having an upwardly protruding mold section, which in the pressed state ( Figure 7 C) Insert the tool into the upper half 50a. Figure 7 D, the two tool halves 50a, 50b can be spaced apart from each other or away from each other by a greater distance AB or path. Figure 7 In the C / D example, a distance of up to 10 mm is allowed. Figure 7 The design of the tool halves 50a, 50b of C / D makes expansion and foaming of the core element 32 possible while preventing plastic material from escaping into the gap between the tool halves 50a, 50b.

[0082] It should be noted that when additional structural elements, such as the reinforcement section 22 ( Figure 3 C. Figure 4 ), the above-mentioned expansion foaming technology can also be used optionally, of course, a mold designed for this purpose should be used.

Claims

1. A flat structural component (10) for a motor vehicle (41), which is an underbody protection element (10) of a motor vehicle (41), the structural component comprising: a flat core element (32) made of a first thermoplastic plastic material, at least one lower covering layer and at least one upper covering layer (34a, 34b) made of a second fiber-reinforced thermoplastic plastic material, wherein the covering layers (34a, 34b) are molded and materially connected to the core element (32), the core element being made of an injection-molded blank accommodated between the covering layers (34a, 34b) or of an extruded blank accommodated between the covering layers (34a, 34b), It is characterized in that The structural member (10) has at least one edge region (16) formed only from the first thermoplastic material and formed integrally with the core element (32) received between the cover layers (34a, 34b), and A plurality of through-openings (26) are provided in the edge region (16), the through-openings being adapted to receive connecting elements which are provided for fastening the structural component (10) to a vehicle body (40), The structural component (10) has at least one rib-shaped reinforcement section (22), wherein the reinforcement section (22) is formed from the first thermoplastic plastic material and wherein the reinforcement section (22) protrudes beyond a covering layer (34a).

2. The structural component (10) according to claim 1, characterized in that The first thermoplastic material is fiber reinforced.

3. The structural component (10) according to claim 2, characterized in that The first thermoplastic material comprises long fibers made of glass.

4. The structural component (10) according to claim 3, characterized in that The length of the long fiber made of glass is 1 mm to 50 mm.

5. The structural component (10) according to claim 4, characterized in that The length of the glass long fibers is 1 mm to 10 mm.

6. The structural component (10) according to any one of claims 1 to 5, characterized in that The second thermoplastic material comprises endless fibers.

7. The structural component (10) according to claim 6, characterized in that The second thermoplastic plastic material comprises glass fibers and / or carbon fibers and / or aramid fibers and / or natural fibers.

8. The structural member (10) according to claim 6, characterized in that The covering layers (34a, 34b) are made of a fiber semi-finished product and / or at least one layer of UD tape.

9. The structural component (10) according to claim 8, characterized in that The fiber semi-finished product is an organic sheet.

10. The structural component (10) according to any one of claims 1 to 5, characterized in that The first thermoplastic plastic material and the second thermoplastic plastic material are compatible with each other in terms of their material properties.

11. The structural component (10) according to claim 10, characterized in that In the case of fiber-reinforced plastic materials, the respective plastic matrix is ​​produced from the same material.

12. The structural component (10) according to claim 11, characterized in that In the case of fiber-reinforced plastic materials, the corresponding plastic matrix consists of polypropylene (PP) or polyamide (PA).

13. The structural component (10) according to any one of claims 1 to 5, characterized in that There is at least one raised section (18) formed jointly in the core element (32) and the cover layers (34a, 34b).

14. The structural component (10) according to claim 13, characterized in that The raised section (18) has a through-opening (20) which is adapted to receive a connecting element which is provided for fastening the underbody protection element (10) to a vehicle body (40, 44).

15. The structural member (10) according to claim 1, characterized in that The reinforcement section (22) is formed on one of the covering layers (34a).

16. The structural member (10) according to claim 13, characterized in that The reinforcement section (22) merges into the raised section (18).

17. The structural component (10) according to claim 16, characterized in that At least one reinforcement section (22) is formed between two raised sections (18).

18. A motor vehicle (41) having a vehicle body (40, 44) and a structural component (10) according to any one of claims 1 to 17, fastened to the vehicle body (40, 44).

19. The motor vehicle (41) according to claim 18, characterized in that The structural component is arranged as a bottom protection element (10) below the energy storage device.

20. The motor vehicle (41) according to claim 19, characterized in that The structural component is arranged as an underbody protection element (10) below a high-voltage battery (42) or a pressure tank.

21. A method (500) for producing a structural component (10) as an underbody protection element for a motor vehicle, comprising the following steps: introducing (S502) a first thermoplastic plastic material provided (S501) as an unshaped plastic material blank between a lower cover layer and an upper cover layer (34a, 34b) made of a fiber-reinforced second thermoplastic plastic material; The first thermoplastic plastic material is modified together with the covering layers (34a, 34b) (S503), wherein during the modification, the first thermoplastic plastic material is distributed between the covering layers (34a, 34b) in such a way that after the modification, the first thermoplastic plastic material forms a core element (32) which is at least regionally covered on both sides by the covering layers (34a, 34b), wherein the introduction (S503b) of the first thermoplastic plastic material is carried out by an injection molding process, wherein the plastic material is injected between the cover layers (34a, 34b), wherein the first thermoplastic plastic material is physically foamed or chemically foamed (S505) during or after being injected between the covering layers (34a, 34b), characterised in that the foaming (S505) is performed by expansion foaming after the injection of the first thermoplastic plastic material, wherein the associated pressing or casting tool elements are moved away from each other after the injection of the first thermoplastic plastic material (S506), In which, at least one rib-shaped reinforcement section (22) protruding from the relevant covering layer (34a, 34b) is applied (S507) to at least one of the covering layers (34a, 34b) in a foamed or non-foamed manner by means of an injection molding process, wherein the reinforcement section (22) is formed by the first thermoplastic plastic material.

22. The method (500) of claim 21, wherein: The unformed plastic material blank is an injection-moldable or extrusion-moldable plastic material blank.

23. The method (500) of claim 21, wherein: The tool halves (50a, 50b) or tool parts of the associated pressing or casting tool element are moved away from each other after the injection of the first thermoplastic plastic material (S506).

24. The method (500) of claim 21, wherein: Before the first thermoplastic plastic material is introduced between the cover layers, long fibers made of glass are added (S504) to the first thermoplastic plastic material.

25. The method (500) according to any one of claims 21 to 24, wherein: The introduction (S503a) of the first thermoplastic plastic material is carried out by an extrusion process, wherein the plastic blank contained between the cover layers (34a, 34b) is extruded by means of pressure.

26. The method (500) according to any one of claims 21 to 24, wherein: The associated pressing or casting tool elements (50a, 50b) are spaced 0.5 mm to 10 mm apart from each other.

27. The method (500) of claim 26, wherein: The associated pressing or casting tool elements (50a, 50b) are spaced 1 mm to 5 mm apart from each other.

28. The method (500) of claim 21, wherein: Glass fibers or minerals or elastic materials are added to the applied plastic material of the reinforcement section (22) in a different proportion than that added to the first thermoplastic plastic material of the core element (32).

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