Fiber composite member and method for producing a fiber composite member

Abstract

A fiber composite member includes an elongate main member and a fastening portion disposed at an end of the elongate main member, the fastening portion has a fastening opening for fastening the fiber composite member to a neighboring part. A reinforcement fiber bundle, which forms a fiber reinforcement of both the elongate main member and the fastening portion, has a first reinforcement fiber and a second reinforcement fiber which run substantially mutually parallel in a region of the elongate main member. A respective part of the first reinforcement fiber and the second reinforcement fiber in a transition region between the elongate main member and the fastening portion depart from a bundle profile in the region of the elongate main member and the respective parts of the first and second reinforcement fibers intersect with one another in the transition region.

Claims

1. A fiber composite member, comprising: an elongate main member; a fastening portion disposed at an end of the elongate main member, wherein the fastening portion has a fastening opening for fastening the fiber composite member to a neighboring part; a reinforcement fiber bundle, which forms a fiber reinforcement of both the elongate main member and the fastening portion, has a first reinforcement fiber and a second reinforcement fiber which run substantially mutually parallel in a region of the elongate main member; an insert disposed in a region of the fastening portion, wherein the insert has a sleeve portion which surrounds the fastening opening; and a mandrel portion, which points in a direction of the elongate main member, is contiguous to the sleeve portion; wherein the insert in a region of the mandrel portion has two clearances which in a vertical direction of the fiber composite member are disposed on both sides of the mandrel portion, wherein the two clearances are delimited on a first side by the sleeve portion and on a second side by two pin-type appendages which are disposed on an elongate main member side end of the mandrel portion and which extend in the vertical direction, wherein a respective part of the first reinforcement fiber and the second reinforcement fiber depart from a bundle profile and are divided by the two pin-type appendages and wherein the respective parts of the first and second reinforcement fibers intersect with one another in an interior of the two clearances of the insert.

2. The fiber composite member according to claim 1, wherein the reinforcement fiber bundle is generated by wrapping.

3. The fiber composite member according to claim 1, wherein the fastening portion is integral to the elongate main member.

4. The fiber composite member according to claim 1, wherein the fastening portion is an end portion of the fiber composite member.

5. The fiber composite member according to claim 1, wherein a crossing point of the first and second reinforcement fibers is compressed.

6. A method for producing the fiber composite member according to claim 1, comprising the acts of: a) wrapping the first and the second reinforcement fibers of the reinforcement fiber bundle in the region of the elongate main member running in a longitudinal direction of the elongate main member; b) crossing the respective parts of the first and the second reinforcement fibers of the reinforcement fiber bundle with one another in the interior of the two clearances of the insert; c) embedding the reinforcement fiber bundle in a plastics-material matrix; and d) curing the plastics-material matrix.

7. The method according to claim 6, wherein a crossing point of the respective parts of the reinforcement fibers are compressed by curing the fiber composite member in a mold.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a plan view of an elongate fiber composite member according to the invention.

(2) FIG. 2 shows a lateral view of the fiber composite member from FIG. 1.

(3) FIG. 3 shows an enlarged illustration of a fastening portion of the fiber composite member from FIG. 1, the illustration highlighting the profile of the reinforcement fibers.

(4) FIG. 4 shows a perspective view of the fastening portion from FIG. 3.

DETAILED DESCRIPTION OF THE DRAWINGS

(5) FIGS. 1 to 4 show an elongate fiber composite member 10 according to the invention, in the form of a strut, which is used in particular in the automotive sector, for example for reinforcing a body. The fiber composite member 10 has an elongate main member 12 as well as two fastening portions 14 which are configured so as to be integral to the main member 12 and which are opposite end portions. Each of the fastening portions 14 has one fastening opening 16 and serves for fastening the fiber composite member 10 to a neighboring part, for example by way of a screw not shown in the Figures.

(6) The fiber composite member 10 has a common fiber reinforcement of the main member 12 and of both fastening portions 14 in the form of a reinforcement fiber bundle 18 which is generated by wrapping and is embedded in a plastics-material matrix 20. The reinforcement fibers 22 of the reinforcement fiber bundle 18 in the region of the main member 12 run so as to be substantially mutually parallel in the longitudinal direction L of the main member 12, as can be derived in particular from FIG. 3.

(7) An insert 24 which is prefabricated from plastics material and around which the reinforcement fibers 22 are guided in a substantially loop-shaped manner is in each case provided in the region of the fastening portions 14, the insert 24 being conjointly embedded in the plastics-material matrix 20.

(8) The insert 24 has a sleeve portion 26 which surrounds the fastening opening 16 and, similar to a yarn spool, is provided with two lateral delimitation disks 28 (see in particular FIG. 4). The reinforcement fibers 22 run around the sleeve portion 26.

(9) It is to be noted here that the fiber-reinforced plastics material of the fiber composite member 10 in FIG. 4 has been illustrated so as to be transparent for reasons of clarity.

(10) A mandrel portion 30 which points in the direction of the main member 12, and by way of the tip 32 thereof extends into the main member 12, is contiguous to the sleeve portion 26. The insert 24 in the region of the mandrel portion 30 has two clearances 34 which in the vertical direction Z of the fiber composite member 10 are disposed on both sides of the mandrel portion 30. Part of the reinforcement fibers 22 of the reinforcement fiber bundle 18 mutually intersecting in each case in the interior of the clearances 34. To this end, part of the reinforcement fibers, identified by 22a, departs from the bundle profile and intersects with other reinforcement fibers 22b which likewise depart from the bundle profile.

(11) The clearances 34 herein are delimited by the sleeve portion 26, on the one hand, and by two pin-type appendages 36 which are disposed on the main-member side end of the mandrel portion 30, close to the tip 32, and which extend in the vertical direction Z (and thus perpendicularly to the longitudinal direction L of the main member 12). The pin-type appendages 36 dividing in each case part of the reinforcement fibers 22 into the two groups 22a and 22b which mutually intersect. Moreover, some reinforcement fibers 22c run laterally along a central region 38 of the mandrel portion 30, without intersecting other reinforcement fibers, between the planes of the intersecting reinforcement fibers 22a and 22b. Of course, non-crossing reinforcement fibers 22c can also be provided beside as well as above and below the intersecting reinforcement fibers 22a, 22b. For improved clarity, the intersecting reinforcement fibers 22a, 22b in FIG. 3 are illustrated in dashed lines, while the non-crossing reinforcement fibers 22c are indicated by solid lines.

(12) The crossing points 40 of the reinforcement fibers 22a, 22b that lie in the region of the clearance 34 are compressed, specifically by curing the fiber composite member 10 in a mold.

(13) In order for the fiber composite member 10 to be produced, the reinforcement fiber bundle 18 is first wrapped, wherein the reinforcement fibers 22 in the region of the main member 12 run in the longitudinal direction L of the main member 12, and the parts 22a, 22b of the reinforcement fibers of the reinforcement fiber bundle 18 are crossed in the transition region between the main member 12 and the fastening portion 14, more specifically in the clearances 34 of the insert 24, while a further part 22c of the reinforcement fibers is guided without crossing laterally along the insert 24.

(14) The reinforcement fiber bundle 18 thus wrapped is embedded in the plastics-material matrix 20, and the latter is cured. In order for an even higher stability to be achieved, the crossing points 40 of the reinforcement fibers 22 are compressed, preferably by curing the fiber composite member 10 in a mold.

(15) The insert 24, and in particular the clearances 34, as well as the pin-type appendages 36 serve for guiding the reinforcement fibers 22 and for generating the crossing points 40 when wrapping the reinforcement fiber bundle 18.

(16) As an alternative to the shown design embodiment having the insert 24 which is of course likewise present in the second fastening portion 14 not shown in FIGS. 3 and 4, and a corresponding wrapping device which has corresponding “wrapping aids” (for example in the form of pins) which enabled the desired fiber profile of the reinforcement fibers 22 can also be used. In this case, the wrapped reinforcement fiber bundle 18 is transferred to a mold and cured therein, wherein the wrapping aid has however been removed prior thereto. Wrapping herein preferably takes place with pre-impregnated reinforcement fibers.

(17) The fiber composite member 10 according to the invention is distinguished by high stability, is significantly lighter than struts from steel or aluminum, and is significantly more cost effective in production as compared to fiber composite members having braided reinforcement fibers.

(18) 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.