Core System, Use of the Core System in the Production of a Fiber Composite Component and Method for Producing a Fiber Composite Component

Abstract

A core system for the production of a fiber composite component includes at least two core elements which are coupled to one another and are displaceable relative to one another. At least one core element has a surface which is oblique to a displacement direction. A method for producing the fiber composite component uses the core system.

Claims

1. A core system for the production of a fiber composite component, comprising: a plurality of core elements which are coupled to one another and are displaceable relative to one another, wherein at least one core element of the plurality of core elements has a face that is oblique to a displacement direction.

2. The core system as claimed in claim 1, wherein at least one core element of the plurality of core elements has a substantially decreasing cross-section.

3. The core system as claimed in claim 1, wherein one of the plurality of core elements is a main core element which has a substantially rectangular cross-section.

4. The core system as claimed in claim 2, wherein one of the plurality of core elements is a main core element which has a substantially rectangular cross-section.

5. The core system as claimed in claim 1, wherein the plurality of core elements each have at least one external face which is part of a shell face of the core system and at least one contact face via which the plurality of core elements bear on one another.

6. The core system as claimed in claim 5, wherein the at least one contact face and the at least one external face of at least one core element of the plurality of core elements run in a mutually oblique manner.

7. The core system as claimed in claim 1, wherein the plurality of core elements are configured from a hard material.

8. The core system as claimed in claim 7, wherein the hard material is a metal.

9. A use of the core system as claimed in claim 1 as a core in a production of a fiber composite component.

10. A method for producing a fiber composite component having a core system as claimed in claim 1, comprising the acts of: a) displacing one of the plurality of core elements in relation to another one of the plurality of core elements along the displacement direction; b) circumferentially braiding the core system with fibers; c) incorporating a matrix-forming material in the braided fibers; d) curing the matrix-forming material to produce the fiber composite component; and e) removing the core system from the produced fiber composite component.

11. The method as claimed in claim 10, wherein the plurality of core elements prior to step e) are displaced in relation to one another.

12. The method as claimed in claim 10, wherein the plurality of core elements during step c) and/or step d) are displaced in relation to one another.

13. The method as claimed in claim 11, wherein the plurality of core elements during step c) and/or step d) are displaced in relation to one another.

14. The method as claimed in claim 10, wherein at least one core element of the plurality of core elements is heated.

15. The method as claimed in claim 11, wherein at least one core element of the plurality of core elements is heated.

16. The method as claimed in claim 12, wherein at least one core element of the plurality of core elements is heated.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 shows a core system according to the invention in a first position.

[0027] FIG. 2 shows the core system according to the invention from FIG. 1 in a second position.

DETAILED DESCRIPTION OF THE DRAWINGS

[0028] A core system 10 for the production of a fiber composite component is shown in FIG. 1. The core system 10 in the embodiment shown has four core elements 12, 14, 16, 18 which are displaceable relative to one another.

[0029] The first core element 12 can also be referred to as the main core element. The second core element 14 and the third core element 16 are in each case disposed so as to be displaceable in relation to the main core element 12.

[0030] To this end, the main core element 12 has a contact face 20 having a groove 22 provided thereon, a corresponding protrusion 24 of the second core element 14 engaging in the groove 22 such that the second core element 14 can be displaced in a guided manner along a displacement direction V.

[0031] The main core element 12 furthermore has a second contact face 26 on which a second groove 28 is configured, in which second groove 28 a protrusion 30 of the third core element 16 engages. The third core element 16 can likewise be displaced in a guided manner along the displacement direction V in relation to the main core element 12.

[0032] Accordingly, the second core element 14 and the third core element 16 by way of the contact faces thereof bear on the respective contact faces 20, 26 of the main core element 12.

[0033] Moreover, the second core element 14 in the embodiment shown has a third protrusion 32 which engages in a groove 34 which is configured on a contact face of the fourth core element 18.

[0034] The third contact element 16 has a fourth protrusion 36 Which engages in a groove 38 which is likewise configured in the fourth core element 18.

[0035] On account thereof, it is possible for the fourth core element 18 to be able to be displaced along the displacement direction V relative to the second and to the third core elements 14, 16. The core element 18 herein is guided by way of the grooves 34, 38 and by way of the protrusions 32, 36 that are provided on the core elements 14, 16.

[0036] The four core elements 12 to 18 by way of, in each case, two contact faces thus already bear on a neighboring core element 12 to 18, wherein the core elements 12 to 18 in each case have external faces which are part of a shell face 40 of the entire core system 10.

[0037] Of the external faces that form the shell face 40, only the external faces 42 of the second core element 14, the external faces 44 and 46 of the forth core element 18, and the external face 48 of the third core element 16 can be seen in FIG. 1. Accordingly, further external faces are on the opposite sides.

[0038] The core elements 14 to 18 furthermore have at least one face which is oblique in relation to the displacement direction V.

[0039] In the embodiment shown, these herein are the respective contact faces between the second core element 14 and the fourth core element 18, and the contact faces between the third core element 16 and the fourth core element 18. These contact faces of the core elements 14 to 18 moreover run obliquely in relation to the respective external faces of the core elements 14 to 18 that run parallel with the displacement direction V.

[0040] The circumference or the dimensions, respectively, of the entire core system 10 can be modified by virtue of the obliquely running faces, that is to say of the contact faces. To this end, the core elements 14 to 18 are displaced in relation to the main core element 12 or relative to one another along the displacement direction V or counter to the displacement direction V.

[0041] This can be derived inter alfa from a comparison of FIGS. 1 and 2, since the core elements 14 to 18 in FIG. 2 are shown in the terminal position thereof in which the circumference of the core system 10 is at a maximum.

[0042] The main core element 12 in the embodiment shown has a substantially rectangular cross-section, whereas the further core elements 14 to 18 have a substantially decreasing cross-section. This means that the cross-section of the core elements 14 to 18 is smaller at a first end than at an end that is opposite the first end. This can be particularly readily seen on the fourth core element 18 in FIG. 1.

[0043] The core elements 14 to 18 can be configured so as to he substantially wedge-shaped.

[0044] The second and the third core elements 14, 16 in the embodiment shown are configured so as to be mirror-inverted, configuring a contiguous functional group of the core system 10, since the core elements 14, 16 are displaced, jointly in relation to the main core element 12. This can also be derived from FIG. 1, since the second and the third core elements 14, 16 are displaced by the same distance relative to the main core element 12.

[0045] By contrast, the fourth core element 18 in the embodiment shown is displaced by double the distance, that is to say twice as far as the second and the third core elements 14, 16.

[0046] In general, the gearing, that is to say the ratio of the adjustment path of the fourth core element 18 as compared to the distances of the second and of the third core elements 14, 16, depends on the angle of the oblique faces of the latter in relation to the displacement direction V.

[0047] Since all the external faces of the core elements 12 to 18 run parallel with the displacement direction V, a substantially rectangular cross-section of the core system 10 results, wherein the shell face 40 is continuous, that is to say without steps. The precise cross-sectional area of the core system 10 is adjustable in that the core elements 12 to 18 are displaced in relation to one another since the core elements 14 to 18 in each case bear on one another by way of oblique faces, that is to say by way of contact faces thereof that are configured so as to be oblique. The continuously configured shell face 40 herein at least in the operating region is not modified, as can be derived from a comparison between FIGS. 1 and 2.

[0048] The core elements 12 to 18 are preferably configured from a hard material, in particular from a metal. It is guaranteed by virtue of the hard material that the core elements 12 to 18 can withstand the pressures that arise during the production method.

[0049] Accordingly, the core elements 12 to 18 are moreover thermally conducting such that the core elements 12 to 18 can serve for heating the fiber composite component during the production. To this end, the core elements 12 to 18 can be connected to a heat source, for example to a heat transmission liquid which is directed through the core elements such that the heat that is released to the core elements is transmitted onward by the core elements 12 to 18.

[0050] Alternatively or additionally, the core elements 12 to 18 can themselves be provided with a heat source. To this end, heating wires which are actuated by a controller of a tool are provided in the core elements 12 to 18, for example.

[0051] The production method of the fiber composite component which can established in a simple manner with the aid of the core system 10 as described above will be described hereunder.

[0052] The core system 10 in a so-called braided position, in which the circumference of the core system 10, or the dimensions of the latter, respectively, are initially decreased in comparison to the terminal position shown in FIG. 2, is illustrated in FIG. 1. The braided position can be considered to be an operating position of the core system 10. The core system 10 in this braided position shown in FIG. 1 is circumferentially braided with the fibers which are intended to become part of the fiber composite component.

[0053] Glass fibers, carbon fibers, ceramic fibers, aramid fibers, natural fibers, nylon fibers, or other fibers can be used herein.

[0054] The circumferentially braided core system 10 is subsequently placed into a tool in which the braided fibers are impregnated or soaked, respectively, with a matrix-forming material. The matrix-forming material can be a plastics material, for example a thermosetting plastic, an elastomer, or a thermoplastic material.

[0055] In an RTM injection-pressing method the matrix-forming material is injected under high pressure into a cavity of the tool. The circumferentially braided core system 10 has been previously placed into the cavity.

[0056] Once the braided fibers have been impregnated or soaked, respectively, with the matrix-forming material, the matrix-forming material is cured, on account of which the fiber composite component is produced.

[0057] In as far as at least one of the core elements 12 to 18 is configured so as to be heatable and/or thermally conducting, the curing of the matrix-forming material can be accelerated.

[0058] The core system 10 is subsequently removed from the fiber composite component produced. The core system 10 can subsequently be reused for the production of another fiber composite component. To this end it is important that the core system 10 can be removed from the fiber composite component produced in a simple and non-destructive manner.

[0059] The variable core system 10 prior to the removal from the braided position which represents an operating position can be displaced to a removal position in which the circumference of the core system 10 is further decreased such that the core system 10 is easier to remove. To this end, the core elements 14 to 18 are displaced in relation to the main core element 12 and/or in relation to one another in the displacement direction V.

[0060] It can furthermore be provided that the core system 10 during the curing of the matrix-forming material, or during the incorporation of the latter into the cavity of the tool, respectively, is displaced counter to the displacement direction V, on account of which the circumference of the core system 10 is increased. On account thereof, the fiber content by volume can be modified during the RIM process, which corresponds to a post-compression of the braided structure that is formed about the core system 10. Accordingly, the core system 10 is expanded such that the fibers can be post-compressed. This position can also be considered to be an operating position which is assumed by the core system 10 prior to the removal.

[0061] In general, the variability of the core system 10 enables the wall thickness and the fiber content by volume of the fiber composite component to be produced to be set by way of the core system 10 even during the production.

[0062] Since the core elements 12 to 18 are configured from a hard material, for example from a metal, it is moreover ensured that a high reproducibility as well as tight tolerances in terms of the wall thickness of the fiber composite component can be achieved.

[0063] By virtue of the core system 10 it is furthermore possible for symmetrical fiber composite components to be produced, the wall thickness of the symmetrical fiber composite components being consistent across the length of the wall.

[0064] In general, a core system 10 by way of which a fiber composite component which has a symmetrical shape and a uniform wall thickness can be produced in a simple manner is achieved.

[0065] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.