METHOD AND PRESS TOOL FOR THE PRODUCTION OF A HYBRID VEHICLE STRUCTURE, AND HYBRID VEHICLE STRUCTURE

Abstract

In a method of producing a hybrid structure, a fiber material is formed three-dimensionally during a pressing process through extrusion in a press tool to produce a functional component. The fiber material is hardened at least in part and directly joined in the press tool with a metal component. Forming of the functional component of fiber-reinforced plastic and joining with the metal component is implemented in a single method step.

Claims

1. A method of producing a hybrid structure, comprising: forming a fiber material three-dimensionally during a pressing process through extrusion in a press tool to produce a functional component; hardening the fiber material at least in part; and directly joining the fiber material in the press tool with a metal component.

2. The method of claim 1, wherein the metal component is a shell-shaped metal structure.

3. The method of claim 1, further comprising forming a metal sheet during the pressing process to the metal component.

4. The method of claim 1, further comprising forming the functional component during the pressing process to a shape of a rib or shape of a bulkhead.

5. The method of claim 1, further comprising structuring at least one region of a surface of the metal component.

6. The method of claim 1, further comprising applying an adhesion promoter upon at least one region of at least one of the metal component and the fiber material prior to the pressing process.

7. The method of claim 6, wherein the adhesion promoter is an adhesive.

8. The method of claim 1, further comprising at least partly heating the metal component prior to the pressing process.

9. The method of claim 1, further comprising heating the fiber material at least in one of the phases selected from the group consisting of prior to the pressing process, during the pressing process, and after the pressing process.

10. The method of claim 1, further comprising providing at least one region of the metal component prior to the pressing process with a covering, mask or coating.

11. The method of claim 1, further comprising forming a layer of fiber-reinforced plastic upon a surface of the metal component in a region adjacent to the functional component.

12. The method of claim 1, wherein the fiber-reinforced plastic includes at least one fiber selected from the group consisting of natural fiber, plastic fiber, glass fiber, aramid fiber, polypropylene fiber, polyamide fiber, metal fiber, and mineral fiber.

13. The method of claim 12, wherein the mineral fiber is carbon fiber or basalt fiber.

14. The method of claim 1, wherein the fiber material is configured as a stack of fiber material layers.

15. A hybrid structure, comprising: a metal component; and a functional component formed through extrusion from fiber material and directly joined with the metal component during extrusion.

16. The hybrid structure of claim 15, wherein the metal component has a U shaped cross section, defining a base web and two side legs respectively connected to the base web, said functional component extending transversely between the side legs.

17. The hybrid structure of claim 16, wherein the functional component is joined with at least one of the base web and the side legs.

18. A motor vehicle, comprising a hybrid structure which includes a metal component, and a functional component which is formed through extrusion from fiber material and directly joined with the metal component during extrusion.

19. The motor vehicle of claim 18, wherein the fiber material is formed three-dimensionally during extrusion and hardened at least in part.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0038] Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which:

[0039] FIG. 1a is a perspective view of a lower tool of a press tool for use in the production of a first embodiment of a hybrid vehicle structure in accordance with the present invention;

[0040] FIG. 1b is a perspective view of the lower tool, with illustration of a ram;

[0041] FIGS. 1c and 1d are perspective views of method steps for the production of the hybrid vehicle structure in accordance with the present invention;

[0042] FIG. 1e is a schematic illustration of the press tool with lower tool and upper tool;

[0043] FIG. 1f is a schematic illustration of the press tool in a closed state;

[0044] FIG. 1g is a perspective view of the hybrid vehicle structure, as viewed obliquely from below;

[0045] FIG. 2 is a simplified and schematic illustration of a press tool for use in the production of a second embodiment of a hybrid vehicle structure in accordance with the present invention;

[0046] FIG. 3 is a schematic illustration of a detail of a metal component, depicting a structured surface; and

[0047] FIG. 4 is a schematic illustration of a detail of a metal component, depicting another variant of a structured surface of a metal component.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0048] Throughout all the figures, same or corresponding elements may generally be indicated by same reference numerals. These depicted embodiments are to be understood as illustrative of the invention and not as limiting in any way. It should also be understood that the figures are not necessarily to scale and that the embodiments may be illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted.

[0049] Turning now to the drawing, and in particular to FIG. 1a, there is shown a perspective view of a lower tool, generally designated by reference numeral 9, of a press tool, generally designated by reference numeral 2 and illustrated in particular in FIG. 1e, for use in the production of a first embodiment of a hybrid vehicle structure in accordance with the present invention. A hybrid structure or hybrid vehicle structure, generally designated by reference numeral 1, is shown in greater detail in FIG. 1g which is a perspective view obliquely from below.

[0050] As shown in FIG. 1g, the hybrid structure 1 includes a shell-shaped metal component 3 and a functional component 4 which is made of fiber-reinforced plastic, e.g. a glass fiber reinforced thermoplastic material, and joined with the metal component 3. The metal component 3 is made of steel material or light metal material. The metal component 3 is configured U shaped in cross section and includes a base web 5 and two side legs 6. The functional component 4 extends transversely between the side legs 6. The functional component 4 is joined with the base web 5 and the side legs 6 across the entire contact area between the metal component 3, and the functional component 4 provides stiffening and reinforcement of the hybrid structure 1. The functional component 4 is formed by extrusion from fiber material 7 and directly joined with the metal component 3 during the extrusion process. In the illustrated non-limiting example, the fiber material 7 is provided in the form of a stack of fiber material plies.

[0051] An exemplified embodiment of the press tool 2 is shown in FIG. 1e and includes a first tool part in the form of an upper tool 8 and a second tool part in the form of the lower tool 9. The upper tool 8 includes a receptacle 10 for the metal component 3. The receptacle 10 has a contour which matches an outer contour of the metal component 3. The lower tool 9 includes a support body 11 (FIG. 1a) of a configuration which complements an inner contour of the metal component 3. Extending on both sides of the support body 11 are outwardly directed flanges 12 (FIG. 1 a). The lower tool 9 has a recess 13 in which a ram 14, shown in FIG. 1b, is movably arranged, with the recess 13 and the ram 14 forming a cavity 15.

[0052] With reference to FIGS. 1c and 1d, the fabrication of the hybrid structure 1 will now be described in greater detail. The fiber material of fiber material plies is placed within the cavity 15 above the ram 14 into the recess 13 (FIG. 1c). The metal component 3 is then placed on top (FIG. 1d). The metal component 3 may be provided with adhesion promoter, in particular glue, across the entire surface or also in at least one region. The metal component 3 may also have a structured surface, at least in the area in which the functional component should be attached.

[0053] After the fiber material and the metal component 3 are united and positioned in the press tool 2 upon the lower tool 9, the press tool 2 is closed. The upper tool 8 moves hereby downwards, as indicated by arrow P1. Air may escape through vents. When the upper tool 8 touches the lower tool 9, both the upper and lower tools 8, 9 continue to move together downwards, as indicated by arrows P1 and P2. During this stroke movement, the metal component 3 is held in place by restraining elements 16. The upper tool 8 and the lower tool 9 move during the downward stroke movement in opposition to the force of spring elements 17 which are arranged below the restraining elements 16 (FIG. 1e). Thereafter, the ram 14 moves in opposite direction upwards, as indicated by arrow P3. As a result of the high pressure and temperature influence, the fiber material 7 is formed by an extrusion process three-dimensionally into the functional component 4 and directly joined with the metal component 3 at the same time. During extrusion, the functional component 4 undergoes at least partial hardening. The forming operation requires heating. For this purpose, the metal component 3 is heated at least in part prior to the pressing process. When the hybrid structure 1 is produced immediately after the metal component 3 undergoes hot forming, any residual heat of the formed metal component can be utilized for the extrusion process. It is also conceivable to heat the fiber material 7 prior to its placement into the press tool 2. Further, the press tool 2 can be heated prior to, during, or after closing of the press tool 2.

[0054] FIG. 1f shows the press tool 2 in the closed state, with the ram 14 having moved upwards. The stack of fiber material 7 of fiber reinforced plastic (FRP) is formed three-dimensionally into the functional component 4 and joined with the metal component 3. A material joint is hereby established. When the metal component 3 has structured surfaces, a form fit and force fit are additionally established.

[0055] Turning now to FIG. 2, there is shown a simplified and schematic illustration of a press tool, generally designated by reference numeral 19, for use in the production of a second embodiment of a hybrid vehicle structure in accordance with the present invention, generally designated by reference numeral 18. The press tool 19 includes a first tool part in the form of an upper tool 20 and a second tool part in the form of a lower tool 21. A cavity 22 is provided in the lower tool 21 and has a contour which matches an outer contour of a functional component 23 to be produced. In the illustrated non-limiting example, a hollow shape is involved for the production of a rib-shaped or wall-shaped functional component 23.

[0056] A fiber material (not shown), e.g. a stack of fiber material mats (short fiber mats or long fiber mats) is positioned upon the lower tool 21 in the area of the cavity 22, and a metal component 23 is then placed upon the lower tool 21. The fiber material is trapped between the lower tool 21 and the inner contour of the metal component 24. Subsequently, the press tool 19 is closed. Under the influence of temperature and high pressure during closing of the press tool 19, the fiber material is shaped by pressure and extruded. The fiber material is hereby formed three-dimensionally in the cavity 21 through extrusion into the functional component 23 and directly joined with the metal component 24 as well as hardened entirely or in part. At the same time, fiber reinforced plastic is slightly displaced from the area of the cavity 22 and forms, at least in part, a thin skin-like layer 25 on the surface of the metal component 24.

[0057] In the mode of production described with reference to FIG. 2, the metal component 24 or the fiber material may be provided with an adhesion promoter prior to the pressing process at least in part. In addition, the metal component 24 may have a structured surface at least in the region of the joining surface. The stack can be heated prior to and/or during and/or after the pressing process. The metal component 24 may also be heated at least in part prior to the pressing process.

[0058] FIGS. 3 and 4 show schematic illustrations of possible structured surfaces of metal component, designated by reference numerals 26 and 27, respectively. Structuring may be realized through stamping or like mechanical processes, such as brushing or grinding. Also chemical treatment for producing a structured surface is conceivable. Advantageously, structuring of the surface is executed during production of the metal component 26, 27, for example as an additional process step in a forming device during cold forming. The structuring of the surface can be configured by undercuts 28, recesses 29 and ribs 30 as well as by scale-like stamping.

[0059] While the invention has been illustrated and described in connection with currently preferred embodiments shown and described in detail, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit and scope of the present invention. The embodiments were chosen and described in order to explain the principles of the invention and practical application to thereby enable a person skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.

[0060] What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims and includes equivalents of the elements recited therein: