Device of Exhaust Gas Treatment and Method for Production Thereof

Abstract

In a device for the aftertreatment of exhaust gases from an emission source, in particular an internal combustion engine, with an exhaust tract through which an exhaust gas can flow in a direction of flow, with at least one catalytic converter, the catalytic converter having a ceramic honeycomb body has: a catalytically active surface coating, and with an electrically heatable heater, the heater having a metallic electrical conductor, the honeycomb body further having a plurality of flow channels which can be flowed through from a gas inlet side to a gas outlet side, wherein the conductor is integrated in the ceramic honeycomb body, and is arranged downstream of the gas inlet side and upstream of the gas outlet side, as viewed in the direction of flow.

Claims

1-12. (canceled)

13. A device for the aftertreatment of exhaust gases from an emission source, in particular an internal combustion engine, with an exhaust tract through which an exhaust gas can flow in a direction of flow, with at least one catalytic converter, the catalytic converter having a ceramic honeycomb body (1, 5, 8, 12, 15) having: a catalytically active surface coating, and with an electrically heatable heater (3, 7, 9), the heater (3, 7, 9) having a metallic electrical conductor (3, 7, 9), the honeycomb body (1, 5, 8, 12, 15) further having a plurality of flow channels which can be flowed through from a gas inlet side (11, 16) to a gas outlet side, wherein the conductor (3, 7, 9) is integrated in the ceramic honeycomb body (1, 5, 8, 12, 15), and is arranged downstream of the gas inlet side (11, 16) and upstream of the gas outlet side, as viewed in the direction of flow.

14. The device as claimed in claim 13, wherein the conductor is arranged in clearances (17) in an end face of the gas inlet side (16) and/or the gas outlet side.

15. The device as claimed in claim 14, wherein the conductor is fixed in the ceramic honeycomb body by means of latching elements.

16. The device as claimed in claim 13, wherein the ceramic honeycomb body (5) is formed from at least two honeycomb bodies configured as disk elements (6), which are arranged one after the other in the direction of flow, each of the disk elements (6) having an integrated conductor (7), with the conductors (7) in the disk elements (6) being electrically conductively connected to one another.

17. The device as claimed in claim 13, wherein a plurality of conductors are integrated in the honeycomb body.

18. The device as claimed in claim 14, wherein the conductor (3, 7, 9) is arranged in a plane parallel to the end face of the gas inlet side (11, 16).

19. The device as claimed in claim 18, wherein the conductor is arranged both in a plane parallel to the end face of the gas inlet side and in a direction transverse to the end face.

20. The device as claimed in claim 13, wherein one or more conductors (7) are arranged in a plurality of mutually parallel planes in the honeycomb body (5).

21. A method for producing the device as claimed in claim 13, the method comprising: shaping, pressing or casting a ceramic powder or granulate to form a shape of the ceramic honeycomb body, pressing the metallic conductor into the formed ceramic honeycomb body, and sintering the honeycomb body having the pressed-in metallic conductor.

22. The method as claimed in claim 21, wherein the metallic conductor is pressed into an end face of the honeycomb body from a gas inlet side in the direction of the gas outlet side.

23. The method as claimed in claim 21, wherein the metallic conductor follows a defined course, the course being arranged in a spiral or meandering manner.

24. The method as claimed in claim 21, wherein a plurality of metallic conductors are pressed into the end face of the honeycomb body.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The invention is explained in detail in the following text on the basis of exemplary embodiments with reference to the drawings, in which:

[0033] FIG. 1 shows a schematic view of the arrangement of a conductor on the end face of a honeycomb body;

[0034] FIG. 2 shows a sectional view through a honeycomb body formed from a number of disk elements;

[0035] FIG. 3 shows a sectional view through a honeycomb body with a pressed-in conductor near the end face of the gas inlet side;

[0036] FIG. 4 shows a view of a ceramic honeycomb body with an upstream heating disk; and

[0037] FIG. 5 shows a sectional view through a honeycomb body with a milled groove for receiving the conductor.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

[0038] FIG. 1 shows a plan view of the end face of a honeycomb body 1. The flow channels 2 can be seen, having a rectangular cross section in the example shown, and also a conductor 3, running in a wavy manner along the end face of the honeycomb body 1. Also shown is a contacting possibility 4, which is used for electrical contacting of the conductor 3.

[0039] It can be seen that the conductor 3 intersects the flow channels 2 and therefore covers a certain proportion of the flow cross section of the channels 2.

[0040] FIG. 2 shows a honeycomb body 5 formed from a number of disk elements 6. Each of the disk elements 6 has a conductor 7. The conductors 7 are electrically conductively connected between the disk elements 6. The conductors 7 therefore form a common conductor that extends through the entire honeycomb body 5. Stacking the disk elements 6 has the effect in practice of producing within the honeycomb body 5 a number of planes in which the flowing exhaust gas is heated.

[0041] FIG. 3 shows a section through a honeycomb body 8. The walls 10 indicate the flow channels, which extend through the honeycomb body 8 from the gas inlet side 11. Reference number 9 designates the electrical conductor, which is arranged analogously to the conductor 3 shown in FIG. 1 such that it is distributed over the cross section of the honeycomb body 8. It can be seen in particular that the conductor 9 is arranged in the immediate vicinity of the end face 11 of the honeycomb body 8.

[0042] FIG. 4 shows a ceramic honeycomb body 12. Arranged upstream of this is a heating disk 13, which is connected to the honeycomb body 12 by connectors 14. The heating disk 13 is preferably also a ceramic honeycomb body, which has a conductor analogous to the previously described figures.

[0043] FIG. 5 shows a section through a honeycomb body 15. Shown on its gas inlet side 16 are clearances 17, which are introduced into the finished, that is to say sintered, honeycomb body. These can be introduced, for example, by a machining process. In a plan view of the gas inlet side 16, the individual clearances 17 can form a contiguous groove into which the conductor is inserted.

[0044] The exemplary embodiments of FIGS. 1 to 5 have in particular no limiting character and serve to illustrate the concept of the invention.

[0045] Although exemplary embodiments are explained in the above description, it should be noted that numerous modifications are possible. It should moreover be pointed out that the exemplary embodiments are merely examples which are not intended to limit the scope of protection, the applications and the structure in any way. Instead, the above description gives a person skilled in the art a guideline for the implementation of at least one exemplary embodiment, wherein various changes may be made, especially with regard to the function and arrangement of the integral parts described, without departing from the scope of protection as it is apparent from the claims and combinations of features equivalent thereto.