INTERIOR TRIM FOR A MOTOR VEHICLE, COMPRISING A HEADLINER AND A STIFFENING FRAME AND METHOD FOR THEIR MANUFACTURE

Abstract

The disclosure provides an interior trim part for a motor vehicle having a sliding or panoramic roof comprising a headliner and a stiffening frame attached to the headliner and enclosing and stabilizing an opening in the headliner enclosing the sliding or panoramic window, the stiffening frame being made of a fiber-reinforced composite material comprising a fiber mat and a textile lattice material, the textile lattice material being applied over a surface of the fiber mat and impregnated together therewith.

Claims

1. An interior trim part for a motor vehicle having a sliding or panoramic roof comprising a headliner (10) and a stiffening frame (14) secured to the headliner (10) and enclosing and stabilizing an opening (12) in the headliner (10) enclosing the sliding or panoramic window, wherein the stiffening frame (14) is made of a fiber-reinforced composite material comprising a fiber mat and a textile lattice material, the textile lattice material being applied flat on a surface of the fiber mat and impregnated together therewith.

2. The interior trim part of claim 1, wherein the textile lattice material is bonded to the fiber mat prior to impregnation.

3. The interior trim part according to claim 2, wherein the bond is a mechanical, thermal and/or chemical bond, in particular by needling, spunlace or thermobonding.

4. The interior trim part of claim 1, wherein the textile lattice material is formed of synthetic fibers, in particular polymer fibers, glass fibers, carbon fibers or natural fibers or mixtures of these fibers.

5. The interior trim part of claim 4, wherein the textile lattice material comprises natural fibers, and the natural fibers comprise cotton, hemp, kenaf, flax, sisal, jute, wood, or mixtures thereof.

6. The interior trim part of claim 4, wherein the textile lattice material comprises synthetic fibers, in particular polymer fiber material made of organic synthetic polymers, such as PET, PP or PA, or other synthetic fibers, such as carbon, aramid, Kevlar or glass fibers polymer fibers.

7. The interior trim part of claim 1, wherein the fiber mat comprises natural fibers, include cotton, hemp, kenaf, flax, sisal, jute, wood or mixtures thereof, and/or comprises synthetic fibers, in particular polymer fiber material of organic synthetic polymers, such as PET, PP or PA, or other synthetic fibers, such as carbon, aramid, Kevlar or glass fibers or mixtures thereof.

8. The interior trim part according to claim 7, wherein the composite material is impregnated with a binder, in particular with a thermosetting binder, in particular epoxy, acrylate, phenol, polyurethane or unsaturated polyester, which is applied or introduced onto and/or into the fiber mat in liquid or powder form, or a thermoplastic binder, in particular a biopolymer, such as PLA, polypropylene, polyester or polyamide, or thermoplastic acrylate, which is introduced into the fiber mat in the form of thermoplastic binding fibers or in liquid form.

9. The interior trim part of claim 8, wherein the composite material of the stiffening frame (14) comprises only the mentioned materials.

10. The interior trim part of claim 1, wherein the textile lattice material comprises meshes or a mesh-like fabric having a circular, elliptical, triangular, rectangular, or other polygonal mesh geometry.

11. The interior trim part of claim 1, wherein the textile lattice material has meshes with a mesh size between 0.5 and 25 mm, in particular 5-12 mm.

12. The interior trim part of claim 11, wherein the textile lattice material is formed with bridges between the meshes, the bridges having a width of 0.5-5 mm.

13. The interior trim part of claim 1, wherein the textile lattice material has an area weight of 30-500 g/m.sup.2.

14. The interior trim part of claim 1, wherein the stiffening frame (14) is composed of a plurality of frame portions fused together in a compression molding process, each frame portion having a fiber mat portion with a textile lattice material on its surface.

15. The interior trim part of claim 1, wherein the stiffening frame (14) is molded or bonded to the headliner (10).

16. A method of manufacturing an interior trim part, comprising: Providing a fiber mat; applying a textile lattice material to the fiber mat; impregnating the fiber mat and the textile lattice material in one process step; manufacturing the reinforcing frame from the impregnated composite of fiber mat and textile lattice material.

17. The method of claim 16, wherein the textile lattice material is mechanically, thermally and/or chemically bonded to the fiber mat prior to impregnation.

18. The method of claim 17, wherein the textile lattice material is needled to the fiber mat prior to impregnation.

19. The method of claim 16, further comprising: cutting the impregnated composite of fiber mat and textile lattice material into frame portions; placing the frame portions in a compression mold so that the frame portions overlap, compression molding the frame portions to form the stiffening frame (14) into a predetermined shape and fuse the frame portions together, and joining the stiffening frame (14) to the headliner (10).

20. The interior trim part of claim 1, wherein the textile lattice material is formed with bridges between the meshes, the bridges having a width of 0.5-5 mm.

Description

DESCRIPTION OF DRAWINGS

[0026] The disclosure is further illustrated below by way of examples with reference to the figures.

[0027] In the figures show:

[0028] FIG. 1 a top view of an interior trim part for a motor vehicle having a headliner and a stiffening frame; and

[0029] FIG. 2 a sectional view through part of the headliner with stiffening frame of FIG. 1 along line A-A.

[0030] FIG. 3 a top view of a portion of a composite material used to make the stiffening frame according to an example;

[0031] FIG. 4 a top view of a lattice material for manufacturing the stiffening frame according to another example;

[0032] FIG. 5 a schematic flow diagram of a process for producing the composite material for the stiffening frame according to an example.

DESCRIPTION OF EXAMPLES

[0033] FIG. 1 shows a headliner 10 for a motor vehicle with an opening 12 which, when the headliner is installed, delimits a sliding or panoramic window. The opening 12 is enclosed and stabilized by a stiffening frame 14. An additional smaller stiffening frame 16 for a front console is molded onto the stiffening frame 14. FIG. 1 further shows fastening elements 18 for fastening the headliner 10 to the inside of a vehicle roof.

[0034] The structure of the headliner 10 and the stiffening frame 14 is shown with further details in the sectional view of FIG. 2. The headliner 10 is constructed as a sandwich with a core layer 20 and a cover or decorative layer 22. The core layer 20 may be a foam layer, e.g., a PU foam layer, and the cover layer 22 may be, e.g., a textile layer, a nonwoven or leather, optionally with a haptic layer, foam, nonwoven or spacer fabric.

[0035] The headliner 10 is curved upward at its edges, which border the opening 12, and is reinforced by the stiffening frame 14. In the example shown, the cover layer 22 is placed around the edge of the core layer 10 and the stiffening frame 14 to form a neat finish. The stiffening frame 14 follows the contour of the headliner 10 and has, for example, a U- or L-profile. It lies flat against the headliner 10. Additional profiling can be provided to stiffen the stiffening frame.

[0036] With regard to the materials for the stiffening frame 14, its manufacture and its connection to the headliner 10, reference is made to the above description and to FIG. 5 and its description.

[0037] FIG. 3 shows a top view of a portion of a composite material for manufacturing the stiffening frame. The composite material comprises, respectively, a fiber mat 30 and a textile lattice material 32 applied to the surface of the fiber mat 30. The fiber mat 30 is made of synthetic fibers, natural fibers or a fiber blend, which may be present in a loose composite or may be mechanically, thermally and/or chemically bonded in advance and optionally compacted. Reference is made to the materials mentioned above, for example. In the examples illustrated herein, the fiber mat 30 comprises natural fibers, for example, flax, jute, hemp or kenaf or blends of these fibers. In various examples, the fiber mat including its binder content may have a nominal area weight of 900-1600 g/m.sup.2 and a thickness of about 2-10 mm in the uncompressed state or 0.8 mm-2 mm when compressed.

[0038] FIG. 3 shows an example of a composite of a bottom fiber mat 30 made of natural fibers and an overlying textile lattice material 32 made of PET, which in the example shown has approximately hexagonal meshes 34 with a mesh size of about 8 mm. In this example, the lattice material is produced by a warp knitting process. The bridge width between the meshes is 1 to 2 mm, in particular 1.2 to 1.7 mm, for example about 1.2 mm, 1.5 mm or 1.7 mm. The meshes have the shape of a polygon, in particular a hexagon. The area weight of the textile lattice material is about 100-300 g/m.sup.2, e.g. about 120 g/m.sup.2, 175 g/m.sup.2, 250 g/m.sup.2 or 300 g/m.sup.2.

[0039] In another example, not shown in the figures, both the fiber mat 30 and the lattice material 32 may be made of natural fibers, for example flax fibers. The lattice material 32 may have, for example, rectangular meshes, particularly square meshes, with a mesh size of approximately 5-15 mm. The lattice material may be made by laying and joining natural fiber threads at the crossing points. The bridge width between the meshes may be, for example, 1 to 2 mm, in particular 1.2 to 1.7 mm, for example, about 1.2 mm, 1.5 mm or 1.7 mm. The area weight of the textile lattice material may be about 150-250 g/m.sup.2, for example about 175 g/m.sup.2 or 220 g/m.sup.2.

[0040] FIG. 4 shows an example of a textile lattice material 32 made of PET that can be used in combination with a natural fiber mat or a synthetic fiber mat. In the example shown, the textile lattice material 32 has approximately circular meshes 34 with a mesh size of approximately 8 mm. In this example, the lattice material is produced by a warp knitting process. The bridge width between the meshes is 1 to 2 mm, in particular 1.2 to 1.7 mm, for example about 1.2 mm, 1.5 mm or 1.7 mm. Meshes have approximately the shape of a circle. The area weight of the textile lattice material is about 100-300 g/m.sup.2, e.g., about 120 g/m.sup.2, 175 g/m.sup.2, 250 g/m.sup.2, or 300 g/m.sup.2.

[0041] Other mesh sizes and shapes are also possible, for example, mesh size in the range of about 1-15 mm, rectangular and round mesh shapes. The textile lattice material may be, for example, warp knitted, knitted, woven or produced as knitted fabric, crocheted fabric or by a similar technique. In other examples, the bridge width between the meshes is, for example, between 0.5 and 2 mm or even between 0.5 and 5 mm. For example, the mesh width may be between 0.5 and 25 mm, and in particular between 5 and 12 mm. The weight per unit area of the textile lattice material is, for example, between 30 and 500 g/m.sup.2. In various examples, the weight per unit area of the composite of fiber mat and textile lattice material may be between 930 g/m.sup.2 and 2100 g/m.sup.2, wherein the weight of 930 g/m.sup.2 may result from using a fiber mat having a weight per unit area of 900 g/m.sup.2 and a textile lattice material having a weight per unit area of 30 g/m.sup.2, and wherein the weight of 210 g/m.sup.2 may result from using a fiber mat having a weight per unit area of 1600 g/m.sup.2 and a textile lattice material having a weight per unit area of 500 g/m.sup.2.

[0042] In preferred embodiments, the fiber mat 30 comprises natural fibers, for example in the form of bast fibers of kenaf, hemp, flax or jute, or a blend of such bast fibers and polyester fibers. The textile lattice material 32 comprises polyamide or polyester fibers or likewise natural fibers in the form of bast fibers of, for example, kenaf, hemp, flax or jute. The binder used is a thermosetting acrylate, which is applied in liquid form to the composite of fiber mat 30 and lattice material 32.

[0043] Bast fibers and thermoset acrylate in fiber mats are already being used successfully in series production today and have the following advantages: they have high specific stiffness, i.e. high rigidity in relation to their weight: they can have similar thermal expansion properties to the headliner with which they are combined in use; and they are easy to process, for example in terms of the equipment required and short cycle times compared with a metal frame.

[0044] Polyester and polyamide fibers are suitable for reinforcing the stiffening frame, for example, because they have good elongation at break properties and can absorb large amounts of energy without tearing. An acrylate binder, in turn, is advantageous in terms of its processing temperature, which is in the range of 160 to 210° C. and does not exceed the melting and/or decomposition temperature of the natural and synthetic fibers proposed here. The natural fibers/bast fibers can be processed at these temperatures. Thus, as described, the proposed materials and combination of materials can be used to significantly increase the energy absorption capacity of the stiffening frame without sacrificing the quality of the stiffening frame in other respects and without increasing the effort required for the manufacturing process.

[0045] In the examples described herein, the fiber mat 30 and the textile lattice material are impregnated together with a thermoset acrylate binder. Other binders may be used, as described above.

[0046] The fiber mat 30 may be produced, for example, by feeding fibers from a staple fiber supply into a mixing chamber, where the fibers are optionally treated with an anti-mold agent, for example, rinsed. In particular, fibers of different origins can be uniformly mixed together in the mixing chamber. Subsequently, the fibers are placed on a conveyor belt, for example, where optionally a weight control can be carried out in the longitudinal direction. The fibers are aligned approximately parallel, for example by carding or an airlay process. Optionally, several layers of fibers can be arranged on top of each other offset from each other, for example by 90°. The resulting fiber mat 30 may be provided on a roll as a precursor to the manufacture of the composite material. Optionally, the aligned fibers may be bonded together intrinsically, for example by mechanical, thermal or chemical bonding and/or consolidation. Processes that may be considered for this include needling, spunlacing, or thermobonding.

[0047] As shown in FIG. 5, the fiber mat 30 thus produced is fed as a precursor to a processing device, at 40, and bonded to a textile lattice material 32, at 42, by placing the textile lattice material 32 on a surface of the fiber mat 30 and bonding it thereto, for example by mechanical, thermal or chemical bonding and/or consolidation. Processes that may be considered for bonding the textile lattice material 32 and the fiber mat 30 include, for example, needling, spunlacing, or thermobonding. Pre-bonding of the directional fibers of the fiber mat 30 prior to their bonding to the textile lattice material 32 is therefore not mandatory, because this bonding (of the fibers within the fiber mat 30) can also take place just when the textile lattice material 32 and the fiber mat 30 are bonded. Subsequently, the composite of fiber mat 30 and textile lattice material 32 is impregnated, for example by immersing the entire composite in an impregnating solution, at 44. Reference is made to the above-mentioned materials for impregnation. This results in a uniform and stable composite of fiber mat 30 and textile lattice material 32.

[0048] The composite thus formed can be stored in rolls or in pieces, at 46. To make the stiffening frame, this composite material can be processed by compression molding, at 48, as described above.