Filter layer for an, in particular conical, honeycomb body for exhaust gas treatment, method for manufacturing the filter layer, honeycomb body and exhaust gas purification device

1. A metallic filter layer for the treatment of exhaust gases of combustion engines, comprising:

at least partially gas-permeable metallic fibrous material having a plurality of segments joined to one another to define opposite filter layer edges of different length, and

a gas-impermeable flange in vicinity of at least one filter layer edge, said gas-impermeable flange being formed by a metallic foil.

2. The filter layer according to claim 1 , wherein at least one of said segments has a trapezoid shape.

3. The filter layer according to claim 1 , wherein said segments have equal-sized filter areas.

4. The filter layer according to claim 1 , wherein the filter layer has a circular ring segment shape.

5. The filter layer according to claim 1 , wherein at least some of said plurality of segments are directly joined to one another by bonding.

6. A honeycomb body, comprising:

at least one filter layer according to claim 1 ;

at least one at least partially structured metal foil; and

a conically-shaped housing;

said at least one filter layer and said at least one metal foil disposed in said housing and forming a multiplicity of channels each having a varying channel cross section.

7. The honeycomb body according to claim 6 , wherein said channels are at least partially closed off at least at one location.

8. A method for manufacturing a filter layer formed of at least partially gas-permeable material, the method comprising the following steps:

a) providing a strip-shaped metallic fibrous nonwoven;

ab) attaching a gas-impermeable flange in vicinity of at least one edge of the fibrous nonwoven;

b) dividing the fibrous nonwoven into a plurality of segments;

c) configuring the plurality of segments to provide the filter layer with opposite edges of different length; and

d) joining the plurality of segments together.

9. The method according to claim 8 , wherein step b) includes cutting the fibrous nonwoven to generate cut profiles being inclined and mirror-symmetrical with respect to a central axis of a segment.

10. The method according to claim 8 , wherein step c) includes alternating positioning of the segments.

11. The method according to claim 8 , wherein at least one of steps ab) and d) includes welding by roll seam welding.

12. The method according to claim 8 , which further comprises:

e) carrying out a side-end machining process in which at least one side of the filter layer obtains a predefined shape.

13. An exhaust gas purification device, comprising:

at least one filter layer according to claim 1 for at least temporarily obstructing and at least partially converting particles of an exhaust gas flow of an internal combustion engine of a motor vehicle.

14. An exhaust gas purification device, comprising:

at least one filter layer manufactured according to claim 8 for at least temporarily obstructing and at least partially converting particles of an exhaust gas flow of an internal combustion engine of a motor vehicle.

15. An exhaust gas purification device, comprising:

at least one honeycomb body according to claim 6 for at least temporarily obstructing and at least partially converting particles of an exhaust gas flow of an internal combustion engine of a motor vehicle.

16. The filter layer according to claim 1 , wherein said gas-permeable metallic fibrous material is welded or brazed.

17. The filter layer according to claim 1 , wherein said segments are welded or brazed to one another.

18. The honeycomb body according to claim 6 , wherein said at least one filter layer is a plurality of filter layers brazed to one another.

19. The filter layer according to claim 1 , wherein said metallic fibrous material has fibers welded to one another.