Method for manufacturing a vehicle body component which is made from fibre-reinforced composite material and has an integrated display layer

Abstract

The invention relates to a method for manufacturing a vehicle body component (2) from fibre-reinforced composite material, the vehicle body component having an integrated display layer (25), wherein the display layer (25) comprises at least one electronic display element (3) which, when supplied with electrical energy, undergoes a visually perceptible change of state, the method being characterised by the steps of: a) laying up, in a lower mould part (40), a fibre-material stack (20) comprising a plurality of fibre-material layers (21, 22, 23, 24); b) producing at least one cable feed-through opening (29) extending through the fibre-material stack (20) comprising the fibre-material layers (21, 22, 23, 24); c) providing the display layer (25) with electrical conductors (37) electrically conductively connected to electrical connection points (36) of the at least one electronic display element (3); d) placing the display layer (25) onto the uppermost fibre-material layer (24) of the fibre-material stack (20) and passing the electrical conductors (37) through to the bottom side () of the fibre-material layers (21, 22, 23, 34) of the fibre-material stack (20); e) closing the lower mould part (40) with a upper mould part (42) to form a closed mould (4), wherein the fibre-material layers (21, 22, 23, 24) and the display layer (25) are enclosed in a mould cavity of the mould (4); f) injecting liquid synthetic resin under positive pressure into the mould cavity of the mould to form an integral wall (16) of the body component (2); and g) opening the mould (4) after a predetermined setting time and removing the vehicle body component (2).

Description

[0001] 1 25 - 0173

[0002] Method for manufacturing a vehicle body component made of fiber composite material with an integrated display layer

[0003] The invention relates to a method for manufacturing a vehicle body component made of fiber composite material with an integrated display layer, wherein the display layer comprises at least one electronic display means, according to claim 1. The invention further relates to a vehicle body component preferably manufactured by such a method according to claim 9, and to a vehicle, in particular a motor vehicle, with at least one such vehicle body component according to claim 11.

[0004] Many car buyers desire customization and personalization of their vehicles' exteriors. Furthermore, such customization and personalization should not be static, but rather adaptable. Vehicles with displays mounted on or attached to the bodywork are already familiar. This is demonstrated and described by...

[0005] DE 102022000005 A1 A decorative film designed as an e-paper or e-ink film for application to the outer body of a motor vehicle, the appearance of which can be changed by applying an electrical voltage. The application of such a known decorative film must be done manually and is therefore very time-consuming. Likewise, the contacting of the electrical conductors of this e-paper decorative film and the laying of the cables must be carried out manually in a time-consuming manner.2 25 - 0173

[0006] The object of the present invention is to provide a method for manufacturing a vehicle body component with an integrated display layer, which can be used in series production, at least for small series. Furthermore, a corresponding vehicle body component suitable for series production is to be provided.

[0007] The part of the problem directed to the method is solved by the features of claim 1. The part of the problem directed to the vehicle body component is solved by the features of claim 9.

[0008] A method for manufacturing a vehicle body component made of fiber composite material with an integrated display layer, wherein the display layer has at least one electronic display means that undergoes a visually perceptible change of state when electrical energy is applied, is characterized by the steps:

[0009] a) Stacking a fiber material pile from a plurality of fiber material layers in a mold base;

[0010] b) Providing at least one cable opening penetrating the fiber material stack of fiber material layers; c) Providing the display layer with electrically conductive conductors connected to the electrical connection points of the at least one electronic display device;

[0011] d) Placing the display layer on the top layer of fiber material in the fiber material stack and passing the electrical conductors through to the underside of the fiber material layers in the fiber material stack; e) Closing the lower mold part with a top mold part to form a closed mold tool, wherein the fiber material layers and the display layer are enclosed in a mold cavity of the mold tool; 3 25 - 0173

[0012] f) Injecting a liquid synthetic resin into the mold cavity of the mold tool under overpressure to form an integral wall of the body component;

[0013] g) Opening the mold after a specified setting time and removing the vehicle body component.

[0014] The integration of the display layer with the electronic display element into the wall of the body component, for example, into an element of the vehicle's outer body skin, according to the invention, makes it possible to provide a display element during the manufacturing of the body component itself, thus eliminating the need for time-consuming subsequent application of a display to a finished body element. Furthermore, the method according to the invention offers the advantage that a resin layer applied to the stack of all layers in the mold during the manufacturing of the body component forms a protective layer over the display layer. With conventional subsequent application of a display layer to the vehicle body, such a protective layer must also be applied manually. The method according to the invention is therefore significantly more cost-effective than the prior art approach.The lowest layer of fiber material from the fiber material stack, which is first inserted into the lower part of the mold, is the layer facing the inside of the vehicle body component in the finished vehicle body component, while the last layer placed on top, the uppermost layer of fiber material from the fiber material stack, which carries the display layer, faces the outside of the vehicle, so that the display layer with the electronic display device is visible from the outside.

[0015] For electrically conductive contacting of the electrical connection points of the at least one electronic display element of the display layer with the current conductors formed, for example, by a flexible ribbon cable or a flexible carrier film with a conductor track arrangement4 25 - 0173

[0016] (Anisotropy Conductive Film - ACF) the conductors are soldered or welded to the connection points using the well-known ACF method.

[0017] The inventive method preferably involves placing the individual fiber material layers dry into the mold base; this is therefore a so-called RTM (Resin Transfer Molding) process. However, it is also fundamentally possible to insert at least some of the fiber material layers as so-called prepregs into the mold and bond them together by heating. Alternatively, at least some of the fiber material layers can be bonded together as prepregs in a heated mold in a prior process step, and the prepreg intermediate thus produced can then be bonded to the display layer and, optionally, to further fiber material layers according to the inventive method.

[0018] Further preferred and advantageous embodiments of the method according to the invention are the subject of dependent claims 2 to 8.

[0019] Preferably, the following steps are provided after step g): h) mechanical removal of the free ends of the conductors from the lowest layer of synthetic resin and

[0020] i) Establishing electrical connections between the individual conductors and a control unit for at least one electronic display device.

[0021] The conductors, which are arranged side by side as electrical conductor tracks on a flat, flexible conductor film, are thus guided to the inside of the body component and can be connected there invisibly to a control unit 5 25 - 0173.

[0022] They are connected, from which electrical signals are then sent to the display device during operation.

[0023] Alternatively, the following steps can be carried out after step d) and before step e):

[0024] d1) Placing a control unit for at least one electronic display means in the mold base within or below the stack of fiber material made of fiber material layers and

[0025] d2) Establishing electrical connections between the individual conductors and the control unit for the at least one electronic display device.

[0026] In this embodiment of the method, the control unit is integrated into the body component during its manufacture.

[0027] In all process variants, it is advantageous if at least one fiber material protective layer () is applied to the top of the display layer after step d) or after step d2). This not only protects the display layer with the at least one display element against subsequent external influences, but also mechanically bonds it more effectively to the fiber material stack.

[0028] It is advantageous if at least one fiber material protective layer consists of a fiberglass fabric. Due to the fiberglass it contains, this fiber material protective layer is characterized by particularly high strength and resistance to external mechanical influences.

[0029] A preferred variant of the method and the resulting body element is one in which the majority of fiber material layers are carbon fiber material layers, glass fiber material layers and / or

[0030] Aramid fiber material layers.6 25 - 0173

[0031] It is also advantageous if the liquid resin injected under pressure into the mold cavity in step f) is an epoxy resin or contains one. Using an epoxy resin creates a transparent layer above the display layer, through which the display layer and, in particular, its display element are clearly visible.

[0032] Preferably, at least one electronic display element of the display layer is formed from or incorporates an E-Ink film. An E-Ink film, also known as an E-Paper film, has the advantage that it only requires an electrical signal when its display state is to change. Once the E-Ink film has assumed a display state, it can be switched off again and consumes no electrical energy while maintaining this display state.

[0033] The part of the problem relating to the vehicle body component is solved by a vehicle body component made of fiber-reinforced composite material with a plurality of fiber material layers embedded in a synthetic resin and an integrated display layer comprising at least one electronic display means. This vehicle body component can preferably be provided with a fiber material protective layer above the display layer, as described above in relation to the method. A control unit can also preferably be connected to the vehicle body component. Preferably, such a vehicle body component has been manufactured according to a method according to the invention described above. 7 25 - 0173

[0034] It is particularly advantageous if the control unit for at least one electronic display device is integrated into the wall of the body component.

[0035] Finally, the invention is also directed to a vehicle, in particular a motor vehicle, with at least one such vehicle body component made of fiber composite material with an integrated display layer.

[0036] Preferred embodiments of the invention with additional design details and further advantages are described and explained in more detail below with reference to the accompanying drawing.

[0037] BRIEF DESCRIPTION OF THE DRAWINGS

[0038] It shows:

[0039] Fig. 1 shows a motor vehicle with a vehicle body having an outer skin;

[0040] Fig. 2 shows a greatly enlarged vertical section through a wall of a vehicle body component according to the invention in a first embodiment and

[0041] Fig. 3 shows a greatly enlarged vertical section through a wall of a vehicle body component according to the invention in a slightly modified second embodiment.

[0042] PRESENTATION OF PREFERRED EXECUTION EXAMPLES

[0043] Fig. 1 shows a motor vehicle 1 with a vehicle body 12 having a body outer skin 10 and at least 8 25 - 0173

[0044] The partially enclosed vehicle interior 11. The outer body skin 10 includes, among other things, a front hood 13 and front fenders 14, 15, each of which forms a vehicle body component that may have an integrated display device and that may have been manufactured according to the inventive method described below. The structure of the wall of the vehicle body component and the method are described below by way of example using the front hood 13 of the motor vehicle. These descriptions apply analogously to other vehicle body components.

[0045] The vehicle body component 2 according to the invention, which forms the front hood 13, for example an engine hood, is shown in Fig. 2 in a greatly enlarged vertical section through a wall 16 of the vehicle body component 2. A plurality of fiber material layers 21, 22, 23, 24 form a fiber material stack 20, which is compressed in a mold 4 between a lower mold part 40 and an upper mold part 42 in a manner known per se, and whose fiber material layers are thereby laminated together.

[0046] First, a nonwoven fabric made of recycled carbon fibers is provided as the bottom, first fiber material layer 21. This first fiber material layer 21 has, for example, a thickness in the range of 0.50 mm to 0.65 mm, and preferably 0.57 mm. A second fiber material layer 22, made of a biaxial carbon fiber fabric with a thickness between 0.20 mm and 0.30 mm, preferably 0.25 mm, is then arranged on top. The fiber angle can be 90° (+ / - 45°), but it can also deviate from this, for example, due to crash requirements. A polyester layer with a thickness between 0.20 mm and 0.35 mm, preferably 0.28 mm, is provided as the third fiber material layer 23. On this third fiber material layer 23, a fourth fiber material layer 24 is provided, which again consists of a biaxial carbon fiber fabric of a9 25 - 0173

[0047] The thickness consists of layers between 0.20 mm and 0.30 mm, preferably 0.25 mm. The fiber angle can again be 90° (+ / - 45°), but it can also deviate from this, for example, due to crash requirements. The above dimensions refer to the respective thickness of the individual fiber material layers in the pressed and laminated fiber material stack 20; the dimensions each indicate an average thickness value.

[0048] On the uppermost, fourth fiber material layer 24, a display layer 25 is provided, which, as an electronic display means 3, comprises an E-Ink film 30 with an E-Ink layer 34. Beneath this layer, a conductor mask layer 33 is provided with a plurality of electrical conductor tracks 35, which extend out of the E-Ink film 30 at at least one edge and form electrical connection points 36 there. Below the conductor mask layer 33, i.e., on its side facing the uppermost fiber material layer 24, a background layer 31 is provided, bonded by means of an adhesive layer 32 and formed by an opaque backsheet.

[0049] A fiber material protective layer 26 is applied to the top surface of the display layer 25. This layer forms a transparent cover for the display layer 25, and in particular for the E-Ink film 30, protecting it from mechanical damage. It also connects the display layer 25 to the fiber material stack 20. The fiber material protective layer 26 is made of a woven glass fiber textile, preferably 160 g / m². 2 formed and has a thickness of 0.10 mm to 0.15 mm, preferably 0.12 mm. An epoxy resin layer 27, 28 is formed below the fiber material stack 20 and above the fiber material protective layer 26. At least the upper epoxy resin layer 28 is transparent so as not to obstruct the view of the display layer 25.10 25 - 0173

[0050] The electrical conductors 35 of the conductor mask layer 33 are electrically connected at their electrical connection points 36 to their respective current conductors 37 of an electrically insulated control line 38.

[0051] The control line 38 serves as the electrical connection to a control unit 39 for controlling the electronic display device 3 of the display layer 25. The control line 38 is formed by a flexible carrier film with an arrangement of conductor tracks, each of which forms a current conductor 37 of the control line 38.

[0052] Due to the arrangement of the display layer 25 on the top side of the fiber material stack 20, the contact described above is also located on or slightly above the top side of the fiber material stack 20. From there, the control line 38, formed by the flexible carrier film with the conductor tracks, is guided through a through-opening 29 formed in the fiber material layers 21, 22, 23, 24 of the fiber material stack 20 to the underside of the fiber material stack 20 or into its lower region, for example between the first fiber material layer 21 and the second fiber material layer 22.

[0053] In a simple, first embodiment of the method according to the invention, the layer structure of which is shown in Fig. 2, the control line 38 is only guided as far as the base of the fiber material stack 20 when inserted into the mold, and the lower free end of the control line 38 is enclosed in the lower resin layer 27 during the casting process. After the vehicle body component 2 is removed, the lower free end of the control line 38 and with it the lower free ends 37' of the conductors 37 are mechanically detached from the lowest resin layer 27. They are then subsequently electrically connected to a control unit.11 25 - 0173

[0054] In a second embodiment of the method, the layer structure of which is shown in Fig. 3 and which otherwise corresponds to the layer structure of Fig. 2, the control line 38 leads below the fiber material stack 20 to the control unit 39, and the free ends 37' of the conductors 37 of the control line 38 are connected to connection contacts 39' of the control unit 39. Although the control unit 39 can be located at any point in the vehicle, in the example shown here it is integrally connected to the vehicle body component 2. For this purpose, the control unit 39 is at least partially embedded in the lower epoxy resin layer 27.

[0055] Alternatively, the control unit 39 can be embedded in the fiber material stack 20, for example between the first fiber material layer 21 and the second fiber material layer 22, with the control line 38 preferably also being routed between the first fiber material layer 21 and the second fiber material layer 22.

[0056] The invention is not limited to the above embodiment, which merely serves to generally illustrate the core concept of the invention. Within the scope of protection, the device according to the invention can also assume other embodiments than those described above. In particular, the device can have features that represent a combination of the respective individual features of the claims.

[0057] Reference numerals in the claims, description, and drawings serve only to improve understanding of the invention and are not intended to limit the scope of protection.12 25 - 0173

[0058] List of reference signs

[0059] 1 motor vehicle

[0060] 2 Vehicle body component

[0061] 3 electronic display device

[0062] 4 Forming tool

[0063] 10 Body shell

[0064] 11 Vehicle interior

[0065] 12 Vehicle body

[0066] 13 front hood

[0067] 14 front fender

[0068] 15 front fender

[0069] 16 wall

[0070] 20 stacks of fiber material

[0071] 21 bottom, first fiber material layer 22 second fiber material layer

[0072] 23 third layer of fiber material

[0073] 24 top, fourth fiber material layer 25 display layer

[0074] 26 Fiber material protective layer

[0075] 27 lower epoxy resin layer

[0076] 28 upper epoxy resin layer

[0077] 29 Passage opening

[0078] 30 E-Ink films

[0079] 31 Background layer

[0080] 32 Adhesive layer

[0081] 33 conductor mask layer

[0082] 34 E-Ink layers

[0083] 35 electrical conductors

[0084] 36 electrical connection point

[0085] 37 electrical conductors

[0086] 38 Control line 13 25 0173

[0087] control unit

[0088] 'Connection contacts of 39

[0089] Mold base

[0090] Shape top

Claims

14 25 - 0173 Method for manufacturing a vehicle body component made of fiber composite material with an integrated display layer Patent claims 1. Method for manufacturing a vehicle body component (2) from fiber composite material with an integrated display layer (25), wherein the display layer (25) has at least one electronic display means (3) which, when supplied with electrical energy, performs a visually perceptible change of state; characterized by the steps: a) Stacking a fiber material stack (20) from a plurality of fiber material layers (21, 22, 23, 24) in a mold base (40); b) Producing at least one cable opening (29) penetrating the fiber material stack (20) of fiber material layers (21, 22, 23, 24); c) Providing the display layer (25) with electrically conductive conductors (37) connected to electrical connection points (36) of the at least one electronic display device (3); d) Placing the display layer (25) on the top fiber material layer (24) of the fiber material stack (20) and passing the electrical conductors (37) through to the underside () of the fiber material layers (21, 22, 23, 34) of the fiber material stack (20); e) Closing the mold lower part (40) with a mold upper part (42) to form a closed mold tool (4), wherein the fiber material layers (21, 22, 23, 24) and the display layer (25) are enclosed in a mold interior of the mold tool (4);15 25 - 0173 f) Injecting a liquid synthetic resin into the mold interior of the mold tool under overpressure to form an integral wall (16) of the body component (2); g) Opening the mold (4) after a specified setting time and removing the vehicle body component (2).

2. Method according to claim 1, characterized by the following steps: h) mechanically removing the free ends (37') of the conductors (37) from the lowest layer of synthetic resin (40) and i) making electrical connections of the individual conductors (37) with a control unit (39) for which at least one electronic display means (3) 3. Method according to claim 1 , characterized by that after step d) and before step e), the following steps are carried out: d1 ) Placing a control unit (39) for the at least one electronic display means (3) in the lower part of the mold inside or below the stack of fiber material (20) made from the layers of fiber material (21, 22, 23, 24) and d2) Establishing electrical connections () between the individual conductors (37) with the control unit (39) for the at least one electronic display means (3).

4. Method according to one of the preceding claims, characterized in that, 16 25 - 0173 that after step d) or after step d2) at least one fiber material protective layer (26) is applied to the top of the display layer (25).

5. Method according to claim 4, characterized by that at least one fiber material protective layer (26) comprises a glass fiber fabric.

6. Method according to any one of the preceding claims, characterized by that the majority of fiber material layers (21, 22, 23, 24) consist of carbon fiber material layers, glass fiber material layers and / or aramid fiber material layers.

7. Method according to any of the preceding claims, characterized by that the liquid synthetic resin injected under overpressure into the interior of the mold tool 4 in step f) is or is an epoxy resin.

8. Method according to any one of the preceding claims, characterized by that at least one electronic display means (3) of the display position (25) is formed by or has an E-Ink film (30).

9. Vehicle body component (2) made of fiber composite material with a plurality of fiber material layers (21, 22, 23, 24) embedded in a synthetic resin and an integrated display layer (25) comprising at least one electronic display means (3), preferably 17 25 - 0173 produced according to a method according to one of the preceding claims.

10. Vehicle body component (2) according to claim 9. characterized by that the control unit (39) for the at least one electronic display means (3) of the display position (25) is integrated into the wall (16) of the body component (2).

11. Vehicle with at least one vehicle body component (2) made of fiber composite material with integrated display layer (25) according to claim 9 or 10.

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