Composite fiber mat for producing a support plate for a motor vehicle component and method for manufacturing the same

Abstract

This disclosure pertains to a composite fiber mat for producing a support plate for a motor vehicle component, wherein at least a first subarea of the composite fiber mat is provided with at least one reinforcing seam.

Claims

1. A composite fiber mat to form a support plate of a motor vehicle component, comprising: an upper surface and a bottom surface; and at least a first subarea of the composite fiber mat is provided with at least one reinforcing seam; wherein the reinforcing seam penetrates the composite fiber mat from the upper surface to the bottom surface; wherein the composite fiber mat is a compression deformable composite fiber mat which comprises fibers disposed in a matrix resin, wherein the fibers comprise natural fibers, synthetic fibers, glass fibers, carbon fibers or a combination thereof; wherein at least a second subarea of the composite fiber mat is not provided with a reinforcing seam; wherein the composite fiber mat is deformable from a planar form into a form having a three-dimensional shape; and wherein the at least one seam is arranged to allow deformation of the composite fiber mat from the planar form into the three-dimensional shape form while counteracting and/or absorbing loads encountered by the composite fiber mat arising from the deformation.

2. The composite fiber mat according to claim 1, wherein the reinforcing seam borders, fills and/or traverses the at least one subarea.

3. The composite fiber mat according to claim 1, wherein the reinforcing seam is produced in the form of one or more loops, circles or other closed ring shapes, in the form of open or closed polygons, in the form of a star, in the form of a sinuous line or a zigzag line or in a combination of these shapes.

4. The composite fiber mat according to claim 1, wherein the reinforcing seam is produced of a reinforcing yarn that comprises carbon fibers, glass fibers, E-glass, synthetic fibers such as polyamide fibers or polyester fibers, basalt fibers, metal, aramide or a combination thereof.

5. The composite fiber mat according to claim 1, wherein the reinforcing seam is produced of a reinforcing yarn that contains a thermoplastic elastomer in order to locally increase the elastomer content of the composite fiber mat.

6. The composite fiber mat according to claim 1, wherein the reinforcing seam is produced of an electrically conductive reinforcing yarn.

7. The composite fiber mat according to claim 1, wherein no additional reinforcing material is attached to the composite fiber mat by means of the reinforcing seam.

8. The composite fiber mat according to claim 1, wherein an additional reinforcing material is fastened on the composite fiber mat by means of the reinforcing seam.

9. The composite fiber mat according to claim 1, wherein the composite fiber mat comprises a mixture of natural fibers and synthetic fiber.

10. The composite fiber mat according to claim 1, wherein the composite fiber mat comprises a fleece material, a formed fabric, a woven fabric, a non-woven fabric, a stitch-bonded fabric, a knitted fabric, a multilayer mat material or combinations thereof.

11. The composite fiber mat according to claim 1, wherein the composite fiber mat is applied onto a honeycomb structure material.

12. A support plate of a motor vehicle component comprising: a composite fiber mat; wherein at least a first subarea of the composite fiber mat is provided with at least one reinforcing seam, and wherein at least a second subarea of the composite fiber mat is not provided with a reinforcing seam; wherein the composite fiber mat is a compression deformed composite fiber mat which comprises fibers disposed in a matrix resin, wherein the fibers comprise natural fibers, synthetic fibers, glass fibers, carbon fibers or a combination thereof; and wherein the support plate is one of three-dimensionally shaped in the region of the first subarea, in which the reinforcing seam is provided, when the support plate forms part of the motor vehicle component; and three-dimensionally shaped, and the first subarea, in which the reinforcing seam is provided, has a contour that at least partially extends along the contour of the three-dimensional shape when the support plate forms part of the motor vehicle component; and wherein, in response to a localized stress applied to an area of the support plate, the at least one seam acts to distribute the localized stress to a larger area of the support plate.

13. The support plate according to claim 12, which is part of an interior trim part, a car body part, an acoustically effective trim part or another structural part of the motor vehicle.

14. A composite fiber mat, comprising: an upper surface, a bottom surface and an area; and at least one reinforcing seam, wherein the at least one reinforcing seam is disposed only in a subarea of the composite fiber mat, the subarea of the composite mat being a localized area of the composite fiber mat less than the area of the composite fiber mat; wherein the reinforcing seam penetrates the composite fiber mat from the upper surface of the mat to the bottom surface of the mat, and is disposed only in the mat; and wherein the composite fiber mat is a compression deformable composite fiber mat which comprises fibers disposed in a matrix resin, wherein the fibers comprise natural fibers, synthetic fibers, glass fibers, carbon fibers or a combination thereof.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) Different examples are described in greater detail below with reference to the figures.

(2) FIG. 1 schematically shows three successive production steps of a composite fiber mat according to an example;

(3) FIG. 2 shows an example of a formed composite fiber mat according to another example;

(4) FIG. 3 schematically shows three successive production steps of a support component with a composite fiber mat according to another example; and

(5) FIG. 4 schematically shows a sequence of processing steps for producing a support component with a composite fiber mat according to another example t.

DESCRIPTION OF EXAMPLES

(6) FIG. 1 shows different processing steps of a composite fiber mat according to an example. The composite fiber mat may have the above-described structure. It may consist of a single-layer mat or a multilayer mat. In the example shown, it comprises a polymer or resin matrix and natural fibers, glass fibers or synthetic fibers, but is not restricted to any of these materials. Any of the above-described materials and combinations thereof can be used. In a first processing step (1), the composite fiber mat 10 is cut to size such that its outer contour corresponds or approximately corresponds to the support component to be produced.

(7) In a second processing step (2) of the example shown, the composite fiber mat is provided with reinforcing seams in the region of two subareas 12, 12. In the context of this application, the subareas 12, 12 are also referred to as first subareas, in which the reinforcing seam is provided. The composite fiber mat 10 also comprises other regions or subareas that lie outside the first subareas 12, 12 and are not provided with a reinforcing seam. The first subareas 12, 12 are chosen and arranged in such a way that they reinforce the composite fiber mat 10 at locations, at which particularly high mechanical stresses are expected during the course of the further processing of the mat and during the use of the support component produced thereof, for example due to tensile forces, compressive forces and bending stresses.

(8) The reinforcing seam 14 may be composed of one or more seam sections in each subarea 12, 12, wherein the seam sections may be shaped differently depending on the expected forces applied to the composite fiber mat 10, for example, in the form of one or more loops, circles or other closed ring shapes, in the form of a star, in the form of a sinuous line or a zigzag line or in combinations of these shapes as illustrated in FIG. 1.

(9) For example, a reinforcing yarn that contains or consists of carbon fibers, glass fibers, synthetic fibers, basalt fibers or metal fibers may be chosen for the reinforcing seam 14. Several interconnected and/or intertwined reinforcing threads can be used. It is likewise possible to use any of the above-described materials and their combinations. The stitch width and the seam density can vary within the first subareas 12, 12 depending on the expected stresses of the composite fiber mat. For example, the stitch widths may lie in the range between 0.2 and 5 mm or in the range between 0.5 and 2 or 3 mm. Depending on the respective requirements, several seams or one looped seam may be provided at small intervals of only 1 or 2 mm or even less and at greater intervals of 2 mm to 2 cm, at intervals of 5 cm to 10 cm or even more. Regardless of the stitch width, the reinforcing seam and the composite fiber mat act as a unit after compression processing of the composite fiber mat.

(10) The reinforcing seam may penetrate the composite fiber mat from its upper surface to its bottom surface. It may be produced, for example, by means of an automated sewing machine or a sewing machine with a two-thread system, in which an upper thread and a lower thread are intertwined. For example, two-thread lock stitching machines or chain stitching machines or other sewing machines or automated sewing machines may be used. The reinforcing seam may be produced in the form of a straight line or in the form of a zigzag stitch.

(11) In one example, the reinforcing seam is produced in the first subareas 12, 12 in the form of an embroidery seam. However, it also is possible to sew onto the composite fiber mat 10, in one or more first subareas 12, 12, an additional reinforcing material such as a mat, woven fabric, non-woven fabric, stitch-bonded fabric, knitted fabric, etc., by means of the reinforcing seam 14. This additional reinforcing material is then only provided in one or more first subareas 12, 12, but not over the surface of the entire composite fiber mat.

(12) In the next processing step (3), the composite fiber mat provided with the reinforcing seam 14 is compressed and thereby compacted. This can be realized in one step in a heating press, in which the composite fiber mat is also heated. The composite fiber mat may also be preheated and subsequently compressed with or without additional heating of the mat. During this process, the material of the composite fiber mat may be compressed, for example, to 10-50% of its original density. In a few examples, a composite fiber mat with an initial thickness between 5 and 20 mm or between 6 and 15 mm is during the compression step (3) compressed to a thickness of a few millimeters, for example to 1-5 mm or 1-2 mm or 1.2-2 mm. In an example, the final thickness amounts to approximately 1.5 mm. The composite fiber mat 10 is also three-dimensionally deformed during the compression step as schematically indicated in FIG. 1. The three-dimensional deformation may take place in the region of the first subareas 12 and 12, as well as outside these subareas. In this case, the subareas 12, 12 with the reinforcing seam 14 are arranged in such a way that they reinforce the mat in the region, in which particularly high mechanical stresses are expected during the shaping or during the subsequent use of the composite fiber mat in a motor vehicle.

(13) Subsequently, the preformed composite fiber mat can be trimmed or cut to its final shape in a punching process in order to furnish the preform for the support plate of the motor vehicle component. The punching process may also take place in the pressing tool.

(14) FIG. 2 shows an example of a composite fiber mat that was formed into a preform 20, wherein reinforcing seams 14 are schematically indicated in this figure. The component illustrated in FIG. 2 is a support component for an interior door panel, which is three-dimensionally deformed in order to produce a curved, three-dimensional geometry in accordance with the design requirements and to thereby provide, e.g., a contour for an armrest or a base for the attachment of a separate armrest, a receptacle for a map pocket, a receptacle or base for the attachment of a door handle or door pull handle or a receptacle for a loudspeaker or other electrical components such as switches or lighting elements.

(15) Reinforcing seams 14 are produced at locations, at which particularly high stresses are expected during the three-dimensional deformation and/or during the use of the support component in the motor vehicle. The reinforcing seam 14 can be produced in the form of several loops or circles, in the form of a sinuous line, in the form of a star and/or along the contour of the subarea to be reinforced as illustrated in FIG. 2. In this case, the reinforcing seam 14 is arranged and aligned in such a way that it allows a desired shaping of the support component and simultaneously counteracts and absorbs peak loads. The reinforcing seam can absorb and/or distribute loads, e.g., upon a side impact as in the example shown, in which an efficient load distribution or absorption is particularly desirable at the H-point (hip point) in order to protect passengers from potentially penetrating sharp-edged objects during the impact. The reinforcing seam can also fulfill this function.

(16) FIG. 3 shows a sequence of processing steps of a support plate for a motor vehicle comprising a composite fiber mat according to another example. In the example according to FIG. 3, the support plate comprises a honeycomb core 28 with a cover layer 26 consisting of a fleece or a film applied onto one or both surfaces of the core 28. The honeycomb core 28 may have a sandwich structure with two cover layers and different core materials, wherein synthetic and natural materials such as paper can be used, and wherein the honeycombs may be filled with air or foam to cite just a few examples. One more layers of a composite fiber mat 30 can be applied onto the honeycomb core 28 or the cover layer(s) 26, wherein the fibers in a multilayer structure may be aligned differently. As in the preceding example, different synthetic fibers and/or natural fibers may be connected to a polymer or resin matrix, wherein the fibers may comprise, for example, polypropylene, polyethylene, polyamide, polyester, glass fibers, carbon fibers or metal. The composite fiber mat can be produced with different techniques and may comprise formed fabrics, woven fabrics, stitch-bonded fabrics, knitted fabrics and the like. Formed fabrics or fleeces in the form of needle-punched fabrics can be produced, for example, by means of carding or aerodynamically.

(17) The composite fiber mat 30 applied onto the honeycomb core 28 comprises first subareas 32, within which reinforcing seams 14 are produced, wherein said reinforcing seams are schematically illustrated in the form of straight and sinuous seams 14 in the second processing step (2) according to FIG. 3. The reinforcing seams 14 are produced in the subareas 32 at locations, at which particularly high mechanical stresses of the support plate are expected. As in the preceding embodiment, they may contain or consist of carbon fibers, glass fibers, synthetic fibers such as, e.g., polyester fibers, metal fibers or basalt fibers.

(18) The example in FIG. 3 also shows that the reinforcing seam 14 can be used for sewing on an additional reinforcing fabric 34 in a subarea of the composite fiber mat. Other subareas of the composite fiber mat are not provided with an additional reinforcing material.

(19) The structure consisting of the honeycomb core 28, the cover layer 26 and the composite fiber mat 30 illustrated in the processing step (2) according to FIG. 3 can then be compressed and, if applicable, deformed in a subsequent processing step (3). In the example shown, the complete structure is compressed into a flat support plate 36 such that the composite fiber mat and the honeycomb core 28 are compacted and their thickness is reduced. However, it is also possible to three-dimensionally deform the structure illustrated in FIG. 3 during the compression process. Further, the thus formed support plate can be trimmed, punched and optionally laminated.

(20) In the example according to FIG. 3, the composite fiber mat 30 can be bonded to the cover layer 26 of the honeycomb core 28. In this example, the reinforcing seam is only produced in the composite fiber mat, but not in the cover layer 26.

(21) FIG. 4 shows a sequence of processing steps for producing a support plate for a motor vehicle component of a composite fiber mat according to an example. The composite fiber mat may be furnished, for example, in the form of a rolled material as indicated with the reference symbol 38 in FIG. 4. It may contain natural or synthetic fibers and have any of the above-described compositions. The matrix or the composite material may consist of a thermoplastic or thermosetting polymer or a resin as described above. The composite fiber mat may have an initial thickness on the order of 3-20 mm or 5-50 mm or approximately 10 mm. The rolled material 38 is trimmed in a first processing step in order to furnish the mat-shaped composite fiber mat 40. This composite fiber mat 40 is in subareas provided with a reinforcing seam 44 in an automated sewing or embroidery machine 50, wherein the reinforcing seam 44 may be sewn or embroidered, and wherein different sewing/embroidering techniques can be used as described above. It is also possible to sew on an additional reinforcing fabric (that is not illustrated in FIG. 4) in the subarea by means of the reinforcing seam 44. The reinforcing seam may be produced with any of the above-described reinforcing threads or reinforcing yarns.

(22) The composite fiber mat 40 provided with the reinforcing seam 44 is placed into a pressing tool 52, wherein the composite fiber mat 40 is heated before it is placed into the pressing tool 52 and/or in the pressing tool 52. The pressing tool 52 is designed in such a way that it compresses and, if applicable, three-dimensionally deforms the composite fiber mat 40. For this purpose, the pressing tool 52 with the composite fiber mat 40 placed therein is closed and held closed with a predefined pressure for a defined time period, for example about one minute. The composite fiber mat also may be formed to its final shape in the pressing tool 52 by means of punching or pinching.

(23) The pressing tool 52 is then opened such that the preformed and, if applicable, the three-dimensionally shaped and trimmed support plate 46 can be removed. The support plate 46 can subsequently be further processed, for example, by means of laminating, by attaching other components or the like. In contrast to the illustration in FIG. 4, it is also possible to heat and pre-compact the composite fiber mat before it is placed into the pressing tool 52 and to three-dimensionally shape the composite fiber mat subsequently in an additional production step. It further is possible to shape the composite fiber mat with other techniques such as, for example, vacuum forming or back injection-molding. In addition, a cover layer can be laminated onto the composite fiber mat and/or other components can be integrated, for example injection-molded, with the composite fiber mat during its deformation.

(24) If the support plate 46 has an initial thickness on the order of 5-15 mm, it may have a thickness on the order of 1-3 mm or, in particular, 1-2 mm or about 1.5 mm after the deformation or shaping process.

(25) The composite fiber mat can be used for producing a support component for a motor vehicle that is used in the interior or exterior region of the motor vehicle. It is suitable for interior trim parts, as well as for car body parts or other exterior components and for invisible trim parts such as, for example, for sound insulation in the motor vehicle. The support component produced of the composite fiber mat may also be laminated and lined with cover layers of synthetic or natural materials, formed fabrics, carpet, etc. The support plate produced of the composite fiber mat can be used for any structural parts in the motor vehicle. Due to the production of the reinforcing seam, the support plate produced of the composite fiber mat can be locally reinforced, wherein the reinforcement is achieved without a noteworthy increase of the weight or the density of the support plate. The additional weight of the reinforcing seam is negligible. Alternatively, it is possible to produce a motor vehicle component with a comparable strength, but with a smaller thickness than a component consisting of a support plate without reinforcing seam and otherwise identical properties.

(26) If a reinforcing yarn consisting of a thermoplastic elastomer such as, for example, a polypropylene yarn is used, the reinforcing seam may further serve as a base for welding the support component to one or more other plastic components. A reinforcing yarn of thermoplastic material particularly allows to locally increase the proportion of thermoplastic material in the composite fiber mat in order to thereby create a base for welding the composite fiber mat to other plastic parts. If a reinforcing yarn containing metal or consisting of metal is used for the reinforcing seam, the reinforcing seam can simultaneously fulfill the function of an electrical conductor in the motor vehicle, for example, in order to drive a light source or a regulating device. In this case, the reinforcing seam can transmit signals, as well as electrical energy. It would also be conceivable to use a reinforcing yarn in the form of an electrical inductor with an insulating sheath for this purpose.