METHOD FOR THE MEDIA-TIGHT CONNECTION OF TWO PLATE-SHAPED COMPONENTS

Abstract

The invention relates to a method for the media-tight connection of two plate-shaped components (1, 2), in particular two monopolar plates for the production of a bipolar plate, comprising the steps of: placing the first component (1) on a surface of a clamping device, placing the second component (2) on the first component (1), closing the clamping device, setting a first weld seam (3) on the second component (2), wherein a welding depth (t) is selected that is less than a material thickness (s) of the second component (2), with the result that a bend (5) is formed along the first weld seam (3) owing to the welding distortion, via which bend the second component (2) comes into linear contact with the first component (1), setting a connecting weld seam (4) on the first weld seam (3), with the result that the two components (1, 2) are welded to one another along the bend (5).

Claims

1. A method for the media-tight connection of first and second plate-shaped components (1, 2) the method comprising the steps of: placing the first component (1) on a surface of a clamping device, placing the second component (2) on the first component (1), closing the clamping device, setting a first weld seam (3) on the second component (2), wherein a welding depth (t) is selected that is less than a material thickness (s) of the second component (2), with the result that a bend (5) is formed along the first weld seam (3) owing to the welding distortion, via which bend the second component (2) comes into linear contact with the first component (1), and setting a connecting weld seam (4) on the first weld seam (3), with the result that the two components (1, 2) are welded to one another along the bend (5).

2. The method according to claim 1, wherein a welding depth (t) of 20 to 80% of the material thickness (s) of the second component (2) is selected when setting the first weld seam (3).

3. The method according to claim 1, wherein a metal sheet having a sheet metal thickness or material thickness (s) of from 50 to 100 μm is used for each of the two components (1, 2).

4. The method according to claim 1, wherein the same tool is used for setting the first weld seam (3) and the connecting weld seam (4).

5. The method according to claim 1, wherein a laser beam (6) is moved over the second component (2) at a rate of at least 0.5 m/s when setting the first weld seam (3).

6. The method according to claim 1, wherein a plurality of first weld seams (3) is set simultaneously.

7. The method according to claim 1, wherein, before the connecting weld seam (4) is set, the second component (2) is secured on the first component (1).

8. The method according to claim 1, wherein a clamping device with clamping jaws is used for the local spring-loading of the two components (1, 2).

9. A method for the media-tight connection of first and second monopolar plates for the production of a bipolar plate, the method comprising the steps of: placing the first component (1) on a surface of a clamping device, placing the second component (2) on the first component (1), closing the clamping device, setting a first weld seam (3) on the second component (2), wherein a welding depth (t) is selected that is less than a material thickness (s) of the second component (2), with the result that a bend (5) is formed along the first weld seam (3) owing to the welding distortion, via which bend the second component (2) comes into linear contact with the first component (1), and setting a connecting weld seam (4) on the first weld seam (3), with the result that the two components (1, 2) are welded to one another along the bend (5).

10. The method according to claim 9, wherein a welding depth (t) of 30 to 70% of the material thickness (s) of the second component (2) is selected when setting the first weld seam (3).

11. The method according to claim 9, wherein a welding depth (t) of 40 to 60% of the material thickness (s) of the second component (2) is selected when setting the first weld seam (3).

12. The method according to claim 9, wherein a metal sheet having a sheet metal thickness or material thickness (s) of from 50 to 100 μm is used for each of the two components (1, 2).

13. The method according to claim 9, wherein the same laser welding machine is used for setting the first weld seam (3) and the connecting weld seam (4).

14. The method according to claim 9, wherein a laser beam (6) is moved over the second component (2) at a rate of at least 0.5 m/s when setting the first weld seam (3).

15. The method according to claim 9, wherein a plurality of first weld seams (3) is set simultaneously by means of a plurality of laser beams (6).

16. The method according to claim 9, wherein, before the connecting weld seam (4) is set, the second component (2) is secured on the first component (1).

17. The method according to claim 9, wherein, before the connecting weld seam (4) is set, the second component (2) is secured on the first component (1) by means of tacking.

18. The method according to claim 1, wherein a clamping device with clamping jaws is used for the local spring-loading of the two components (1, 2).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The invention and its advantages are explained in greater detail below with reference to the attached drawings. More specifically:

[0023] FIG. 1 shows a schematic longitudinal section through two plate-shaped components to be connected, and

[0024] FIG. 2 shows a schematic longitudinal section through the two components of FIG. 1 after connection.

DETAILED DESCRIPTION

[0025] FIG. 1 shows, by way of example, two plate-shaped components 1, 2 lying one on top of the other, it being possible, in particular, for these to be two thin metal sheets, for example two monopolar plates, for the production of a bipolar plate.

[0026] For the media-tight connection of the two components 1, 2, the first component 1 is first placed on a surface of a clamping device (not illustrated). The second component 2 is then placed on the first component 1, with the result that the two components 1, 2 lie flat against one another. The two components 1, 2 are then clamped by closing the clamping device, and their position with respect to one another is thus fixed. A comparatively simple clamping device can be used for fixing.

[0027] A first weld seam 3 is then set on an upper side 2.1 of the second component 2 with the aid of a laser beam 6 of a laser welding machine (not illustrated). The welding depth t of the first weld seam 3 is approximately half the material thickness s of the second component 2 in the region of the weld seam 3. This means that component 2 heats up more on its upper side 2.1 than on its lower side 2.2. As a result of the welding distortion, a bend 5 is formed, along which the second component 2 comes into linear contact with the first component 1. To the left and right of the bend there are wedge-shaped gaps 7, which are not only tolerated but are also desirable since they are used for degassing.

[0028] After the first weld seam 3 has been set and the bend 5 has been formed, a second weld seam is set as a connecting weld seam 4, preferably with the same tool and without prior reclamping of the clamping device, to be precise exactly on the first weld seam 3, with the result that the two components 1, 2 are welded to one another along the bend 5. The linear contact between the two components 1, 2 in this region contributes to the fact that the connecting weld seam 4 has no defects and is thus media-tight.