METHOD FOR PRODUCING A COMPOSITE TUBE FOR A MOTOR VEHICLE BODY AND ALSO COMPOSITE TUBE AND MOTOR VEHICLE

Abstract

The present disclosure provides a composite tube and a method for producing a composite tube for a vehicle body. The method includes the steps of: providing a metal tube; forming the tube into a prespecified shape; introducing a spray gun into the tube; and spraying on a fiber coating in at least one region of the inner side of the tube using the spray gun. The fiber coating is a matrix material with embedded fibers. The method further includes removing the spray gun from the tube, and hardening the fiber coating. The present disclosure also provides a motor vehicle having a vehicle body which includes a composite tube.

Claims

1. A method for producing a composite tube for a vehicle body, the method comprising: providing a metal tube; forming the tube into a prespecified shape; introducing a spray gun into the tube; spraying a fiber coating in at least one region of an inner side of the tube using the spray gun, wherein the fiber coating is a matrix material with embedded fibers; removing the spray gun from the tube; and hardening the fiber coating.

2. The method according to claim 1, wherein the tube is formed from steel or aluminum.

3. The method according to claim 1, wherein the tube has at least one cross-sectional enlargement, and the fiber coating is sprayed on a region of the cross-sectional enlargement.

4. The method according to claim 3, wherein the fiber coating is only sprayed on the at least one cross-sectional enlargement of the tube.

5. The method according to claim 1, wherein the tube is formed from aluminum, and the hardening of the fiber coating takes place within a process for an artificial aging of the aluminum.

6. The method according to claim 1, wherein the hardening of the fiber coating takes place within a process for baking of a lacquer coating on a motor vehicle.

7. The method according to claim 1, wherein the tube is formed into the prespecified shape by hydroforming.

8. A composite tube for a vehicle body, the composite tube produced according to the method of claim 1.

9. The composite tube according to claim 8, wherein the fiber coating is applied in sections in a form of a reinforcement pattern.

10. The composite tube according to claim 9, wherein the reinforcement pattern is selected from the group consisting of ring-like, truss-like, and waffle-like forms.

11. A motor vehicle having a vehicle body that includes at least one composite tube according to claim 8.

12. The motor vehicle according to claim 11, wherein the composite tube is included in at least one of a side structure or a roof structure of the vehicle body.

13. The motor vehicle according to claim 11, wherein the composite tube is a roof strut which connects an A-column to a C-column or to a D-column.

14. The method according to claim 1, wherein the embedded fibers are carbon fibers.

15. The method according to claim 1, wherein the matrix material includes at least one of a resin or plastomers.

16. The method according to claim 1, wherein walls of the tube have a constant thickness along a length of the tube.

17. The method according to claim 1, wherein the spray gun includes at least one nozzle that is directed toward an inner surface of the tube.

18. The method according to claim 1, wherein spraying the fiber coating comprises the steps of continuously spraying the fiber coating while rotating the tube around a longitudinal axis and simultaneously moving the tube in an axial direction relative to the stationary spray gun.

19. The method according to claim 1, wherein spraying the fiber coating comprises the steps of continuously spraying the fiber coating while rotating the spray gun and simultaneously moving the spray gun in an axial direction through the stationary tube.

20. The method according to claim 1, wherein spraying the fiber coating comprises the steps of continuously spraying the fiber coating while rotating the tube around a longitudinal axis and simultaneously moving the spray gun in an axial direction through the tube.

Description

DRAWINGS

[0031] In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which:

[0032] FIG. 1 shows a longitudinal section through a tube for use in a method according to the teachings of the present disclosure;

[0033] FIG. 2 shows an introduction of a spray gun into the tube according to FIG. 1;

[0034] FIG. 3 shows a beginning of a spraying on of a carbon fiber coating on an inner side of the tube according to FIG. 1;

[0035] FIG. 4 shows continuing spraying on a carbon fiber coating;

[0036] FIG. 5 shows an end of spraying on of a carbon fiber coating;

[0037] FIG. 6 shows a longitudinal section through a tube after removing a spray gun;

[0038] FIG. 7 shows a first perspective view of a composite tube; and

[0039] FIG. 8 shows a second perspective view of the composite tube according to FIG. 7.

[0040] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

[0041] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

[0042] A method according to the present disclosure provides a tube 10 produced from a metal, in which the tube in at least one region is to be reinforced with fibers, that is to say with carbon fibers, for example. For the tube, steel or aluminum can be used. By way of example, FIG. 1 shows a longitudinal section through such a tube 10. In this case, the shape and the dimensions of the tube 10 are only by way of example and serve for explanation of the present disclosure. The tube 10 can therefore also have other shapes.

[0043] The tube 10 according to FIG. 1 can for example be a tube which on a side structure or roof structure, such as a roof strut, of a motor vehicle connects an A-column to a C-column or to a D-column. It has a tube wall 11 which in one region has a cross-sectional enlargement 12. In this region, the inside diameter of the tube 10 is enlarged, wherein such a cross-sectional enlargement can also be provided at other places of the tube 10.

[0044] This shape, or a different shape, of a tube can be created for example by means of hydroforming. In this case, a tube with initially constant cross section is introduced into a closed mold and by applying an internal pressure is brought into a prespecified shape. The wall thickness of the tube 10 can in this case be constant or variable over its length.

[0045] A specially designed spray gun 20 is introduced into the interior of this tube 10, as is to be gathered from FIG. 2. This spray gun 20 is dimensioned so that its nozzle 21 can be brought into a defined position inside the tube 10. In this case, the spray gun 20 has one or more nozzles, wherein for simplification only one nozzle 21 is shown in the figures. This nozzle 21 is directed toward the inner surface of the tube 10, wherein it points upward, for example.

[0046] Using the spray gun 20, a mixture of matrix material and fibers, e.g. carbon fibers, can then be sprayed onto a region of the inner surface of the tube 10. As a result, a continuous fiber coating 30, that is to say a carbon fiber coating 30, for example, is created, wherein as matrix material a resin such as epoxy resin for example can be used. In one form, the continuous spraying on is carried out by the tube 10 being rotated around its longitudinal axis and by an axial movement of the tube 10 relative to the spray gun 20 taking place. Alternatively, the tube 10 can also be stationary and the spray gun 20 rotated and moved in the axial direction through the tube 10. Also possible are mixed shapes in which for example the tube 10 is rotated and the spray gun 20 is moved axially through the tube 10 (or vice versa) at the same time.

[0047] In this way, the inner surface of the tube 10 can be sprayed continuously with fibers, e.g. with carbon fibers, wherein in the selected exemplary form only the region of the cross-sectional enlargement 12 is sprayed with fiber-reinforced plastic, e.g. with carbon fiber-reinforced plastic. FIG. 3 shows in this case the beginning of the spraying on process, FIG. 4 shows a point in time in the middle and FIG. 5 shows the end of the spraying on process. At the end, the region of the cross-sectional enlargement 12 is provided completely with a fiber coating 30, e.g. with a carbon fiber coating 30. The spray gun 20 can then be removed from the pipe. This situation is shown in FIG. 6.

[0048] The figures show in this case the fiber coating 30, e.g. the carbon fiber coating 30, in the still longitudinally sectioned tube 10. The tube 10 which is thereby provided with a carbon fiber coating 30 is subjected to a hardening process in an oven by supplying heat so that the fiber coating 30, that is to say for example the carbon fiber coating 30, is hardened. As a result of this, the composite tube which is to be produced is formed.

[0049] FIG. 7 shows the entire tube in a first perspective view, wherein it is now a composite tube 10 with a carbon fiber coating on the inside for reinforcement. FIG. 8 shows this composite tube 10 in a second perspective view.

[0050] The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the substance of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.