Structural cladding part

Abstract

Structural cladding part for a vehicle with an inner shell (12) and an outer shell (16), in which the inner shell (12) is made of a thermoplastic plastic in sandwich construction, the outer shell (16) is made of a plastic and is arranged relative to the inner shell (12) in such a way that an inner surface (18) of the outer shell (16) bears at least partially against an outer surface (20) of the inner shell (12).

Description

The invention relates to a structural trim part for a vehicle, in particular for a motor vehicle.Structural trim parts are components on the vehicle that perform both optical and mechanical functions. Such trim parts typically do not serve as load-bearing components, but must nevertheless be suitable for absorbing mechanical loads.Roof spoilers, wind deflectors, hoods or comparable planar components in the exterior or exterior region of vehicles are examples of structural trim parts. These have the task of concealing underlying structures, covering cavities and / or positively influencing the aerodynamic properties of the vehicle. These are therefore subjected to fluid-mechanical forces and, as a result, must neither fail nor be they allowed to deform to a great extent. For this reason, the construction of these components requires a certain structural stability. Secondly, exterior components must meet high requirements with respect to their optical appearance. This must not be too severely impaired even under weather conditions.A customary manner of production is the so-called LFI method (LFI: Longfiber-injection), in which a deep-drawn plastic shell is sprayed with a resin-glass fiber mixture and back-fed in a second process step. A disadvantage of this method is, for example, the lack of sustainability of the thermosetting-plastic-based plastic. Because of its chemical cross-linking during production, there is no reversion. The material can therefore not be fed back to any further process. Consequently, this is special waste which can be used as filler in road construction in the best case. On the other hand, there is little light-weight potential due to the massive construction.The publication DE 10 2008 039 406 A1 describes a method for producing hollow bodies from two or more half shells of different sizes fused together from thermoplastic plastics. In the method, a deep-drawn film web is fused with one or more smaller deep-drawn elements.The publication DE 10 2018 131 722 A1 discloses a molding tool for joining trim parts to sheet-like decorative materials and a corresponding method. The molding tool has a first and a second mold half, which can be positioned relative to one another in an open position and a closed position and between which a joining gap is provided. In addition, a holding frame is provided which is releasably fixed to one of the mold halves adjacent to the joining gap.Against this background, a structural trim part having the features of claim 1 is presented. Embodiments will be apparent from the dependent claims and from the description.The structural cladding part presented is designed for use in or on a vehicle, in particular a motor vehicle, and has an inner shell and an outer shell. The inner shell is made of a thermoplastic material in sandwich construction, i.e. the inner shell has a sandwich structure.The outer shell is likewise manufactured from a plastic and is arranged with respect to the inner shell in such a way that the inner surface of the outer shell abuts at least in sections against the outer surface of the inner shell.The structural trim component presented should be capable of supporting itself and should be relatively rigid and should not break under load.In sandwich construction, materials with different properties are assembled in layers to form a component. The sandwich structure of the inner shell is typically characterized by two mutually opposite outer layers, between which a core layer is provided. The outer layers regularly have high mechanical properties, i.e. they can absorb high mechanical loads without these being impaired.The core layer spaces the two outer layers apart. Usually, the core layer is particularly light, i.e. it has a low density, in particular a lower density than the outer layers. Although the same material as in the outer layers can in principle be used as material for the core layer, this material then has a different morphology.Thermoplastics are distinguished in that they become soft and moldable when heated and cure again when cooled without their chemical structure being changed.In one embodiment, the structural cladding part is designed as a planar component and is configured for use in the outer region of the vehicle. This planar component is provided to give an optical impression and must also be suitable for absorbing mechanical loads or loads.It should be noted that the trim part and the associated manufacturing method are suitable for many applications. This includes, for example. Vehicle interiors, boat hulls and façades of buildings. In summary, it can be stated: wherever lightweight and rigidity are functional requirements made possible by sandwich materials. Aesthetic requirements are met by exterior plastics.In one embodiment, the trim part is designed as a component selected from a group consisting of: roof spoiler, wind deflector, hood.The outer shell can be designed as a deep-drawn component.Furthermore, the outer shell can be manufactured from a thermoplastic material.For the inner shell and the outer shell, polymers of the same type can be used, which then typically have different morphologies and thus different properties.The inner shell can be stamped at least in sections, for example on the end face. This is merely an option.In addition, further functional elements can be integrated on the inner shell.In a further embodiment, the inner shell has a recess in at least one region.In the case of the proposed structural cladding part, in one embodiment only thermoplastic-based plastics are used, which can generally be recycled.The realization of lightweight construction and structural stability is to be made possible by the use of thermoplastic-based sandwich materials which are distinguished in that they have outer or outer layers which are kept at a distance by means of a structured core layer and thus ensure a high overall structural rigidity with a relatively low overall density. A second component in the same type of polymer configuration coats the structural sandwich material and provides a weather-resistant and visually appealing outer skin.The thermoplastic outer shell deep-drawn in configuration meets the requirements for visual appearance and weathering resistance. However, this cannot provide the required rigidity alone. However, the outer shell presented can allow complex geometries, degrees of deformation or drawing depths, which cannot be produced with the sandwich material of the inner shell.The sandwich structure of the inner shell behind the outer shell basically ensures the required rigidity, which is frequently necessary due to aerodynamic loads. In addition, carrier or holding elements can be fastened to it, by means of which forces are introduced or removed into or from the component. This structural element can either support the outer surface over the entire surface or else only partially. This depends on the complexity of the outer shell, complex regions are optionally cut out on the sandwich material in order to simplify the forming thereof. On the other hand, it depends on the mechanical requirements. In areas in which mechanical loads occur, sandwich material reinforces, areas not subject to stress are intentionally left out. In addition, the morphology of the sandwich material, in particular with regard to material and wall thickness distribution, can be adapted to the corresponding structural requirements.It is understood that the features mentioned above and those still to be explained below can be used not only in the respectively specified combination, but also in other combinations or alone, without departing from the scope of the present invention.Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawing.BRIEF DESCRIPTION OF THE DRAWINGFIG. 1 shows two representations of an embodiment of the presented structural cladding part. FIG. 2 shows a flow chart of a possible embodiment of the method for producing the presented structural cladding part.Embodiments of the InventionThe invention is schematically illustrated in the drawing on the basis of embodiments and is described in detail below with reference to the drawing.FIG. 1 shows in two representations an embodiment of the presented structural cladding part, which is denoted overall by the reference numeral 10. The illustration on the left side shows the structural cladding part 10 in a perspective view. On the right side, the structural cladding part 10 is shown in a schematic sectional illustration.FIG. 1 shows an inner shell 12 which is made of a sandwich material made of thermoplastic material. This inner shell 12 can have recesses 14, in particular in complex regions. Furthermore, an outer shell 16 is shown, which is designed as a deep-drawn outer shell 16.The inner shell 12 and the outer shell 16 are arranged with respect to one another such that an inner surface 18 of the outer shell 16 bears almost largely against an outer surface 20 of the inner shell 12.The complete construction of the component shown in FIG. 1 consists of thermoplastic-based materials. In this way, the possibility for recycling can also be preserved.A two-shell, monomaterial composite construction is thus realized, in which a structural inner shell 12 and an outer shell 16, which is particularly optically appealing and which additionally protects against weather influences, are provided.As the illustration shows, on the inner side of the component in the invisible area is the structural, thermoplastic-based sandwich material, which is formed and optionally stamped in a thermoforming process. In this step, the inner shell 12 receives its basic shape, which in principle corresponds to the component surface. However, this can also be omitted in certain areas.For lateral sealing or consolidation, the sandwich material can be stamped on the end face. This can likewise be done in areas which are later provided with screw connections. The solid material structure ensures a secure screwing event in this region. For further functionalization, further functional elements can be fastened in the inner shell 12 by welding methods.The outer shell 16 of the structural trim part 10 is usually based on the same polymer as the inner shell 12 and is generally produced by a deep-drawing process. The outer surface 20 of the inner shell 12 and the inner surface 18 of the outer shell 16 are almost congruent. The outer shell 16 may be manufactured separately and subsequently connected to the inner shell 12. This can optionally also be drawn directly over the inner shell 12.FIG. 2 is a flow chart illustrating one possible sequence of the method for manufacturing a structural trim part of the type described herein.In a first step 50, the inner shell is manufactured and shaped with a sandwich structure, wherein a thermoplastic material is used. This inner shell then substantially already has the shape of the structural cladding part to be produced. In a further step 52, the outer shell is then applied to the inner shell in a deep-drawing process, wherein after this step 52, the outer shell largely covers the outer surface of the inner shell. Finally, in a step 54, functional elements are attached to the inner shell. The attachment of the functional elements can also take place before the deep-drawing of the outer shell.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2008 039 406 A1

[0005] DE 10 2018 131 722 A1

[0006]

Claims

Structural cladding part for a vehicle having an inner shell (12) and an outer shell (16), in which the inner shell (12) is produced from a thermoplastic material in sandwich construction, the outer shell (16) is produced from a plastic material and is arranged with respect to the inner shell (12) in such a way that an inner surface (18) of the outer shell (16) abuts at least in sections against an outer surface (20) of the inner shell (12).Structural trim part according to claim 1, which is designed as a planar component and is designed for use in the outer region of the vehicle.Structural trim part according to claim 2, which is formed as a component selected from a group consisting of: roof spoiler, wind deflector, hood.Structural cladding part according to one of Claims 1 to 3, in which the outer shell (16) is designed as a deep-drawn component.Structural trim part according to one of Claims 1 to 4, in which the outer shell (16) is produced from a thermoplastic material.Structural cladding part according to one of Claims 1 to 5, in which polymers of the same type are used for the inner shell (12) and the outer shell (16).Structural cladding part according to one of Claims 1 to 6, in which the inner shell (12) is stamped at least in sections.Structural trim part according to claim 7, in which the inner shell (12) is stamped on the trim side.Structural trim part according to one of Claims 1 to 7, in which further functional elements are integrated on the inner shell (12).Structural cladding part according to one of Claims 1 to 9, in which the inner shell (12) has a recess (14) in at least one region.

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