Method of manufacturing a reinforcement

Abstract

A method for manufacturing a reinforcement for reinforcing a structural element in a motor vehicle comprises the steps of: pultrusion of a carrier element having a longitudinal axis which, in the state of use, extends along a longitudinal axis of the structural element, wherein the carrier element has a plurality of outer surfaces which extend in the direction of the longitudinal axis; arranging an adhesive on at least one outer surface of the carrier element; and cutting the pultruded carrier element to length.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method for producing a reinforcement for reinforcing a structural component in a motor vehicle. BACKGROUND

[0002] Structural components, for example the body and / or frame of a transport and delivery vehicle, in particular a water or land vehicle or an aircraft, in many cases comprise structural parts having cavities in order to enable a lightweight construction. However, these cavities are the cause of various problems. Depending on the type of cavity, it must be sealed in order to prevent the ingress of moisture and dirt which lead to corrosion of the structural component. It is also often desirable to significantly reinforce the cavities and thus the structural component, but to keep the weight low. It is also often necessary to stabilize the cavities and thus the structural component in order to reduce noise which would otherwise propagate along or through the cavities.

[0003] So, especially in automotive construction, but also in aircraft construction and shipbuilding, mainly reinforcements (English: reinforcers) are used for reinforcing cavities. A known method for producing such reinforcements is to injection-mold a carrier part in a two-component injection-molding process and to spray an expandable adhesive as a second component on one outer side of the carrier part. Such a reinforcement is inserted into a cavity of a structural component, where the adhesive then expands under the action of heat, thereby bonding the carrier part to the structural component.

[0004] A disadvantage of such and similar known reinforcements or methods for producing reinforcements is that the material of the carrier part can be a limiting factor in terms of mechanical stability in the overall system. However, with the injection-molding process described above, the material selection in terms of carrier part material is limited, so that here no arbitrary optimization in terms of mechanical stability is possible. However, the mechanical stability of the system is of great importance even in structural regions which are relevant in the event of a crash, since for such applications the greatest possible mechanical stability is desired. SUMMARY

[0005] It is therefore an object of the present invention to provide an improved method for producing a reinforcement, which method in particular enables a reinforcement having improved mechanical stability to be provided. Furthermore, the method for producing a reinforcement according to the invention also allows an efficient and cost-optimized production of the reinforcement to be achieved.

[0006] This object is achieved by a method for producing a reinforcement for reinforcing a structural component in a motor vehicle, comprising the following steps: pultrusion of a carrier part, which has a longitudinal axis which, in the state of use, extends along a longitudinal axis of the structural component, wherein the carrier part has a plurality of outer surfaces which extend in the direction of the longitudinal axis; arranging an adhesive on at least one outer surface of the carrier part; and cutting-to-length the pultruded carrier part.

[0007] This solution firstly has the advantage that by means of the pultrusion of the carrier part, a carrier part having better mechanical stability can be produced. By means of the use of continuous fibres along the longitudinal axis direction of the carrier part, a much more stable carrier part can be achieved.

[0008] A further advantage is that by means of the pultrusion method, less tooling investment costs should be required than with injection moulding. For example, only one model element (moulding element) has to be adjusted in order to be able to use one production plant for the production of carrier parts having different cross sections in the case of pultrusion. In contrast, in the case of injection moulding, a new injection mould has to be produced for each different carrier part, which leads to high investment costs.

[0009] The solution presented here furthermore has the advantage that the entire production of the reinforcement can thereby be carried out in one uninterrupted production line. This leads to a simplification of the entire process flow. In the ideal case, no further reworking steps of the cut-to-length reinforcement are required.

[0010] In one exemplary embodiment, continuous fibres are used in the pultrusion of the carrier part.

[0011] In one exemplary embodiment, glass fibres and / or carbon fibres and / or aramid fibres and / or natural fibres are used.

[0012] In another exemplary embodiment, a polyamide component is used as a matrix which surrounds the fibres in the pultrusion of the carrier part.

[0013] In a preferred development, polyamide 6 is used.

[0014] In another exemplary development, a polyamide which is polymerised in situ is used.

[0015] In a first alternative embodiment, an adhesive is arranged on the pultruded carrier part before the cut-to-length of the carrier part.

[0016] This has the advantage that a compact and cost-optimised production line can thereby be achieved.

[0017] In a second alternative embodiment, the pultruded carrier part is cut to length before an adhesive is arranged on the outer side of the carrier part.

[0018] This sequence in the production process has the advantage that greater design flexibility is thereby possible in the further process flow. For example, all sizes of cut-to-length carrier parts can be processed, which is difficult to achieve in a process flow with a continuous production line.

[0019] In principle, various adhesives can be used as adhesive.

[0020] In a first exemplary embodiment, the adhesive is a shape memory material.

[0021] Such a shape memory material is described, for example, in the publication WO 2019 / 145503 A1.

[0022] In one exemplary development, the method comprises the further step of: extruding the adhesive in order to transfer the adhesive into a stressed state.

[0023] In one exemplary development, the adhesive is extruded by means of a roller.

[0024] In another exemplary development, the adhesive is arranged on the carrier piece before the carrier piece is cut to length.

[0025] In another exemplary development, the adhesive is extruded before the carrier piece is cut to length.

[0026] The use of a shape memory material as adhesive has the advantage that the arrangement and preparation of the adhesive can thereby be realized in one continuous production line. In this way, for example, the adhesive applied to the carrier piece can be guided through an extrusion station in which a roller transfers the adhesive into a stressed state.

[0027] In an alternative embodiment, the adhesive is an inextensible adhesive.

[0028] In one exemplary development, the inextensible adhesive expands by less than ± 20%, preferably by less than ± 10%, particularly preferably by less than ± 5% upon activation.

[0029] An exemplary commercially available material which can be used as such an inextensible adhesive is available under the trade name SikaPower®.

[0030] In another exemplary embodiment, the adhesive is an extensible adhesive.

[0031] In one exemplary development, the extensible adhesive has an expansion rate of between 50 and 800%, preferably between 50 and 500%, particularly preferably between 100 and 400%.

[0032] An exemplary material which can be used as extensible adhesive is available under the trade name SikaReinforcer®. An alternative material which can be used as extensible adhesive is available under the trade name SikaBaffle®.

[0033] In another exemplary embodiment, the adhesive is a non-expandable adhesive, wherein an expandable material is additionally arranged underneath the adhesive.

[0034] In a preferred development, the expandable material is first arranged on the at least one outer surface of the carrier part, and then the non-expandable adhesive is arranged on the expandable material. Thus, the expandable material is finally arranged between the carrier part and the non-expandable adhesive.

[0035] By such an arrangement, the non-expandable adhesive can be pressed onto the structural part by the expandable material when it is activated, so that a connection between the structural part and the carrier part can be constituted.

[0036] A material available under the trade name SikaBaffle® can be used as expandable material, for example. A material available under the trade name SikaPower® can also be used as non-expandable adhesive, for example.

[0037] In an exemplary embodiment, the method comprises the further step of extruding or spraying an additional element onto the carrier part.

[0038] Providing such a step has the advantage that thereby a design possibility of the reinforcement independent of the production direction of the pultrusion method is provided. Thus, for example, an additional element can be added which does not extend along the longitudinal axis of the carrier part.

[0039] In an exemplary development, the carrier part has a different material than the additional element.

[0040] In an exemplary development, the additional element is free of fibers, wherein the carrier part contains fibers in the longitudinal direction of the carrier part.

[0041] In an exemplary development, the additional element is extruded or sprayed onto the carrier part by a nozzle integrated in the production line before the carrier part is cut to length.

[0042] In an alternative development, the additional element is extruded or sprayed onto the carrier part by a robot after the carrier part is cut to length.

[0043] In an exemplary embodiment, the additional element is configured as a rib or a plurality of ribs, which rib extends substantially transversely to the longitudinal axis of the carrier part and which rib increases the torsional stiffness and / or the bending stiffness of the carrier part.

[0044] In an exemplary embodiment, the additional element is arranged as a wall on the at least one outer surface of the carrier part.

[0045] In a preferred development, the at least one wall limits the adhesive in at least one direction on the outer surface of the carrier piece.

[0046] The provision of one such wall or of a plurality of such walls has the advantage that the adhesive is thereby mechanically protected prior to its arrangement in the structural element. This, for example, reduces the risk of the adhesive being scratched or knocked off the carrier piece. Furthermore, such a wall has the advantage that the adhesive can be guided by the wall during the expansion upon activation of the adhesive or, in the case of inexpandable adhesives, is held in shape.

[0047] In an exemplary embodiment, the additional element is configured as at least one spacer.

[0048] In an exemplary development, the at least one spacer is in contact with the structural element in the used state of the reinforcement, thereby defining the position of the reinforcement relative to the structural element in at least one direction.

[0049] In an exemplary embodiment, the additional element is configured as an expandable element.

[0050] In an exemplary development, the expandable element functions as a seal in its expanded state.

[0051] In an exemplary embodiment, the additional element is extruded or sprayed on the carrier piece in a plurality of process steps and / or by a plurality of nozzles.

[0052] The manufacture in a plurality of process steps has the advantage that greater freedom in terms of material and shape can thereby be ensured.

[0053] In an exemplary embodiment, the additional element contains a polyamide.

[0054] In an exemplary embodiment, the additional element is extruded or sprayed around the carrier piece such that the additional element is oriented substantially transversely to the longitudinal axis of the carrier piece.

[0055] In an exemplary embodiment, the method comprises the additional step of extruding or spraying a second additional element onto the carrier piece and / or onto the first additional element.

[0056] In an exemplary development, the first additional element has a different material than the second additional element.

[0057] In another exemplary development, the first additional element has a different bending strength and / or a different breaking load than the second additional element.

[0058] In one exemplary embodiment, the method includes the additional step of bending the pultruded carrier component.

[0059] Here, the bending can be achieved before or after the fixed-length cutting. Attached Figure Description

[0060] The details and advantages of the present invention are described below with reference to embodiments and schematic diagrams. The accompanying drawings show:

[0061] Figure 1A This is an exemplary diagram of a pultrusion molding method;

[0062] Figure 1B This is an exemplary diagram of another station in a pultrusion production line;

[0063] Figure 1C This is an exemplary diagram of a downstream workstation;

[0064] Figure 2 This is an exemplary illustration of a three-dimensional view of a reinforcement component;

[0065] Figures 3A to 3C This is an exemplary diagram of the cross-section of the reinforcement; and

[0066] Figure 4 and 5 This is an exemplary illustration of a three-dimensional view of a reinforcing member. Detailed Implementation

[0067] exist Figures 1A to 1C An exemplary method for manufacturing a reinforcement is illustrated herein. Figure 1A The overall plan of this method is shown, and Figure 1B and 1C Further details of each section in this manufacturing method are shown. Here, in Figure 1B The diagram schematically illustrates a section of the production line that includes other workstations, and... Figure 1C The diagram shows downstream stations that are not located in the main production line of the pultrusion process.

[0068] according to Figure 1A During pultrusion, fibers 2 are first guided from fiber spindle 1 through a resin tank 3. A profile 10 is then formed and cured in a curing mold 4. A drawing tool 5 ensures that the fibers 2 are under tension in an orderly manner during these process steps. Thus, a profile 10, serving as a carrier element, is manufactured through these steps. Finally, a length-cutting station 6 divides the continuously produced profile 10 into length-cut elements 7.

[0069] exist Figure 1B The diagram schematically illustrates the workstations within the production line, arranged according to...Figure 1A In section 8 of the overall plan view, a first adhesive application station 21 is shown in this embodiment. At this station, adhesive is applied to the already pultruded profile 10. In this embodiment, a shape memory material is used as adhesive. Furthermore, the adhesive is extruded and transferred into a stress state by rollers 28 in an extrusion station 22. Furthermore, in this embodiment, there is also an extrusion station 23, by means of which additional elements are extruded onto the profile 10 or the carrier part by means of a nozzle 29.

[0070] In Figure 1C , downstream stations are shown schematically, which are arranged in section 9 of the overall plan view according to Figure 1. In this embodiment, there are a first downstream station 24, a second downstream station 25 and a third downstream station 26. The downstream stations 24, 26, 26 have in common that a process step is carried out here on the cut-to-length element 7 of the pultruded profile 10, respectively. For example, a first additional element can be extruded or sprayed onto the carrier part at the first downstream station 24. At the second downstream station 25, for example, adhesive can be applied to at least one outer surface of the carrier part. At the third downstream station 26, for example, a second additional element can be extruded or sprayed onto the carrier part and / or the first additional element.

[0071] In order to manufacture a reinforcement from the pultruded profile 10, it is possible, for example, to use only the stations of the production line, or only the downstream stations, or both the stations of the production line and the downstream stations.

[0072] In Figures 2 to 5 , a reinforcement 16 is then shown exemplarily and schematically, which can be manufactured by the method according to Figures 1A to 1C .

[0073] In Figure 2 , a reinforcement 16 is shown schematically and exemplarily. The reinforcement 16 has a carrier part 11, which has a longitudinal axis 15. The carrier part 11 has a plurality of outer surfaces 17, which extend in the direction of the longitudinal axis 15. On these outer surfaces 17, adhesive 13 is arranged. In this exemplary embodiment, the reinforcement 16 has no further additional elements, such as ribs or walls or spacer elements.

[0074] In Figures 3A to 3C , a cross section of an exemplary reinforcement 16 is shown schematically.

[0075] In Figure 3AA reinforcing element 16 with a trapezoidal cross section is shown in Fig. 1. The carrier element 11 is provided on three outer surfaces with an adhesive 13, which is enclosed on the sides by walls 14. Such walls 14 are therefore advantageous, since they protect the adhesive 13 from mechanical influences on the one hand and ensure that the adhesive 13 swells or the shape stability of the adhesive 13 when the adhesive 13 is activated on the other hand.

[0076] In Fig. 2 a further exemplary cross section of a reinforcing element 16 is shown schematically. In this embodiment, the carrier element 11 has a rectangular cross section. In this embodiment, an expandable material 19 and an adhesive 13 arranged on the expandable material are arranged on two of the wider outer surfaces 17 of the carrier element 11. The expandable material 19 and the adhesive 13 are also enclosed on the sides here by walls 14. When the expandable material 19 and the adhesive 13 are activated, the adhesive 13 is pressed onto the inner side of the structural element by the swelling of the expandable material 19. Figure 3B In Fig. 3 a further exemplary cross section of a reinforcing element 16 is shown schematically. In this embodiment, the carrier element 11 has a rectangular cross section. In this embodiment, an expandable material 19 and an adhesive 13 arranged on the expandable material are arranged on two of the wider outer surfaces 17 of the carrier element 11. The expandable material 19 and the adhesive 13 are also enclosed on the sides here by walls 14. When the expandable material 19 and the adhesive 13 are activated, the adhesive 13 is pressed onto the inner side of the structural element by the swelling of the expandable material 19.

[0077] Figure 3C In Fig. 4 a further exemplary cross section of a reinforcing element 16 is shown schematically. In this embodiment, the carrier element 11 has a M- or W-shaped cross section. An adhesive 13 is arranged on each of the four outer surfaces. In addition, the reinforcing element 16 also has spacer elements 18, which define the spacing of the carrier element 11 from the structural element (not shown) in the use state of the reinforcing element 16.

[0078] In Fig. 5 a perspective view of an exemplary reinforcing element 16 is shown schematically. Here, the carrier element 11 has a substantially U-shaped cross section, and an adhesive 13 is arranged on the outer surfaces 17 of the carrier element. In this embodiment, the reinforcing element has additional elements in the form of ribs 12, which extend transversely to the longitudinal extension of the carrier element 11. By providing such ribs 12, the torsional and / or bending stiffness of the carrier element is increased. Figure 4 Now a perspective view of a reinforcing element 16 is shown schematically in Fig. 6. In this embodiment, the carrier element 11 has a rectangular cross section. An adhesive 13 is arranged on one of the outer surfaces 17 of the carrier element 11. In this embodiment, the adhesive 13 is limited on all sides by walls 14.

[0079] Figure 5 List of reference signs

[0080] 1 Spindle

[0081] 2 Fiber

[0082] 3 Resin tank

[0083] 3 Resin tank ​​

[0084] 4 curing mold

[0085] 5 drawing tool

[0086] 6 fixed-length cutting station

[0087] 7 fixed-length cut element

[0088] 8 section of the production line with stations

[0089] 9 section with downstream stations

[0090] 10 continuous profile

[0091] 11 carrier piece

[0092] 12 rib

[0093] 13 adhesive

[0094] 14 wall

[0095] 15 longitudinal axis

[0096] 16 reinforcement

[0097] 17 outer surface

[0098] 18 spacer element

[0099] 19 expandable material

[0100] 21 adhesive application station

[0101] 22 extrusion station

[0102] 23 extrusion station

[0103] 24 first downstream station

[0104] 25 second downstream station

[0105] 26 third downstream station

[0106] 28 roller

[0107] 29 nozzle

Claims

1. A method for producing a reinforcement (16) for reinforcing a structural component in a motor vehicle, the method comprising the following steps: - pultruding a carrier component (11) having a longitudinal axis (15) which, in the state of use, extends along a longitudinal axis of the structural component, the carrier component (11) having a plurality of outer surfaces (17) extending in the direction of the longitudinal axis (15); - arranging an adhesive (13) on at least one outer surface (17) of the carrier component (11); and - cutting the pultruded carrier component (11) to length, the method comprising the further step of forming at least one wall (14) by extruding or spraying onto at least one outer surface (17) of the carrier component (11), wherein the wall (14) delimits the adhesive (13) on the outer surface (17) in at least one direction. The adhesive (13) is a shape memory material. The method comprises the further step of:

2. The method of claim 1, wherein, - extruding the adhesive (13) in order to transfer the adhesive (13) into a stressed state.

3. The method of claim 2, wherein, The adhesive (13) is arranged on the carrier component (11) before cutting the carrier component (11) to length and / or the adhesive (13) is extruded before cutting the carrier component (11) to length. The adhesive (13) is extruded by means of a roller.

4. The method of claim 2 or 3, wherein, The method comprises the further step of:

5. The method of claim 3, wherein, - extruding or spraying an additional element (12, 18) onto the carrier component (11).

6. The method of any one of claims 1 to 3, wherein, The additional element (12, 18) and / or the wall (14) is extruded or sprayed onto the carrier component (11) by means of a nozzle (29) integrated in the production line before cutting the pultruded carrier component (11) to length. The additional element (12, 18) and / or the wall (14) is extruded or sprayed onto the carrier component (11) by means of a downstream station (24, 26) after cutting the pultruded carrier component (11) to length.

7. The method of claim 6, wherein, The additional element (12, 18) and / or the wall (14) is configured as a rib which extends transversely to the longitudinal axis (15) of the carrier component (11) and which increases the torsional stiffness and / or the bending stiffness of the carrier component (11).

8. The method of claim 6, wherein, The additional element (12, 18) and / or the wall (14) is configured as at least one spacer element which, in the state of use of the reinforcement (16), is in contact with the structural component and defines the position of the reinforcement (16) relative to the structural component in at least one direction.

9. The method of claim 6, wherein, The additional element (12, 18) and / or the wall (14) is extruded or sprayed onto the carrier component (11) in a plurality of process steps and / or by means of a plurality of nozzles (29).

10. The method of claim 6, wherein, The additional element (12, 18) and / or the wall (14) comprises a polyamide.

11. The method of claim 6, wherein, The additional element (12, 18) and / or the wall (14) is extruded or sprayed around the carrier component (11) such that the additional element (12, 18) and / or the wall (14) is oriented transversely to the longitudinal axis (15) of the carrier component (11).

12. The method of claim 6, wherein, The method comprises the additional step of:

13. The method of claim 6, wherein, - extruding or spraying the additional element (12, 18) and / or the wall (14) onto the carrier component (11) in a plurality of process steps and / or by means of a plurality of nozzles (29).

14. The method of claim 6, wherein, ​ A second additional element is extruded or sprayed onto the carrier piece (11) and / or onto the additional element (12, 18) and / or the wall (14) as the first additional element.

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