WO2010102700A1

WO2010102700A1 - Assembly and exhaust gas treatment device

Info

Publication number: WO2010102700A1
Application number: PCT/EP2010/000820
Authority: WO
Inventors: Christoph Noller; Wolfgang Hahnl; Marco Ranalli; Stephan Gross
Original assignee: Emcon Technologies Germany (Augsburg) Gmbh
Priority date: 2009-03-13
Filing date: 2010-02-10
Publication date: 2010-09-16
Also published as: DE102009013007A1

Abstract

The invention relates to an assembly, in particular for an exhaust gas treatment device, for treating exhaust gases of an internal combustion engine, having a body (18) made at least in segments of a gas-permeable substrate, and at least one connecting element (22) for connecting the body (18) to a wall element (16) of a housing (12). The connecting element (22) comprises a first segment (20) embedded in the substrate of the body (18).

Description

Assembly and Abgasbehandlunqsvorrichtung

The invention relates to an assembly, in particular for a

Exhaust treatment device for the treatment of exhaust gases of a

Combustion engine, with a body which at least partially consists of a gas-permeable substrate, and a

Exhaust treatment device.

For the treatment, in particular for the purification, of exhaust gases of combustion engines, e.g. Diesel engines of a passenger car, it is known to arrange porous, gas-permeable substrates in a closed housing in an exhaust pipe, so that the substrate is flowed through by the exhaust gas. In the pores of the substrate, unwanted particles can be deposited, and / or a catalytically active coating causes a conversion of pollutants by chemical means.

As substrates, for example, porous metal bodies are used, which may consist of a metal foam, metal sponge or a metallic hollow spherical structure, but also of a Drahtgewirk or knitted fabric. Such substrates, but especially the metal foams or metal sponges, have a certain brittleness, so that the secure and permanent attachment of bodies of such substrates in the housing is given special attention. In particular, the forces which result from the exhaust gas flow flowing through, from the different thermal expansions of substrate and housing during operation of the motor vehicle, are to be considered, since the coefficient of thermal expansion of substrate and metal housing is different, and vibrations. It is an object of the invention to provide a safe and easy way for one

To propose attachment of such a body.

To achieve this object, an assembly is provided according to the invention with a body which consists at least in sections of a gas-permeable substrate, and at least one connecting element for connection of the body with a wall element of a housing, wherein the connection element has a first portion which is embedded in the substrate of the body. Instead of using, as is conventional, an external surface of the body for attachment, for example by clamping, the fixed connection created between it and the volume of the body by embedding the connection part can be used to establish a connection between the body and the wall element.

The embedding of the first portion of the connecting element in the substrate can be done, for example by Einsintern. In this case, at a stage where the geometric structure of the substrate has already been formed, but the substrate has not yet been exposed to the high temperatures of the sintering process, which determines its later hardness, the first portion of the connecting element is introduced into the body. During the subsequent sintering process, a firm connection then arises between the substrate and the first section of the connecting element.

Preferably, the outer surface of the first portion is completely enclosed by the substrate of the body in order to create the largest possible possible connection.

The first portion of the connecting element may for example be embedded at an axial end of the body. This is particularly suitable for bodies that are shaped in the form of a hollow body, such as a cylinder or truncated cone.

According to a first preferred embodiment of the invention, the first

Section of the connecting element in the form of a tube. The tube may be parallel or transverse to the axial direction of the body, which is generally the

Flow direction of the exhaust gas in the exhaust gas treatment device corresponds to be arranged.

In a second preferred embodiment, the connecting element is in

Formed an elongated metal strip. In this case, preferably, the first portion is a part of the sheet metal strip, which is embedded over a large area in the substrate of the body. This results in the advantage of a large surface over which the body and the connecting element come into contact stand together, which allows an effective and firm attachment of the connecting element to the body.

In a third preferred embodiment, this is

Connecting element of a wire mesh. This design offers the advantage that when sintering the body, a connection between the

Substrate and the mesh of the wire mesh results, resulting in a very strong and secure attachment of the connecting element in the body.

According to a fourth preferred embodiment, this is

Connecting element of a threaded bush. This is completely or partially embedded in the body over its axial length. In this case, the attachment of the body in a housing is particularly simple, since the body can be attached via a simple screw on the wall element.

There may be provided a plurality of distributed over the circumference of the body threaded bushes to ensure the most uniform possible load on the body.

In order to increase the adhesion between the substrate and the first portion of the connecting element and thus to ensure a secure attachment of the connecting element to the body, the first portion of the connecting element may have at least one protruding tab. This results in a toothing of substrate and connecting element, which improves the adhesion of the substrate to the connecting element and improves the force distribution and the power transmission between the connecting element and the body.

The tabs are preferably transverse to the loading direction by the gas flow or the thermal expansion of the body or the housing.

Preferably, the surface of the first portion of the connecting element that is in contact with the substrate has a structure that ensures a firm connection with the substrate. In this case, for example, the surface may be roughened or wavy or have small protrusions or depressions, a groove structure, or a number of a plurality, preferably small openings. Importantly, the structure has a high adhesion between the substrate and the first section of the Joining element allows to distribute the attacking force well and to create a firm connection between the substrate and the connecting element.

For a simple attachment of the body to the housing, the connecting element advantageously has a second section which can be fixedly connected to the wall element of the housing. The connecting element has, so to speak, a multi-part structure: The first section serves for fastening the connecting element to the body, while the second section or also further sections serve for fastening the assembly of connecting element and body to a housing. In this way, a different task can be met easily. On the one hand, the brittle substrate can be securely fastened, and on the other hand, almost any suitable connection to a housing can be realized in a simple manner. The second portion of the connecting element may be formed for example in the form of a flexible angled sheet. The sheet metal can be easily connected to the housing, e.g. by screwing, soldering, welding or gluing. By bending a certain flexibility can be achieved at the same time, so that different thermal expansion coefficients of body and housing can be compensated in a simple manner.

The second portion and the first portion of the connecting element can either be made in one piece with each other, or the second

Section may preferably be secured to a portion of the first section protruding from the body by any suitable fastening method such as screwing, soldering or welding.

The second portion may also be formed as an internal thread, which allows to fasten the assembly simply by means of a screw connection.

The body may be a hollow body, in particular a cone, truncated cone or cylinder. It may also consist of several nested concentrically arranged hollow bodies, for example two inverted nested conical or truncated pyramids. The substrate is preferably a metal foam, a metal sponge, a metallic hollow sphere structure or a wire mesh. Of course, other substrates can be used in which a porous structure is present, in which a connecting element can be embedded. The embedding can be done, for example, before or after a sintering process.

The above object is also achieved with an exhaust gas treatment device in which an assembly described above is used, comprising a housing having at least one wall element, wherein the body is received in the housing and exhaust gas flows through and wherein the second portion of the connecting element, the body connects to the wall element.

For example, the exhaust treatment device may be a particulate filter, but may also be a suitable catalyst, e.g. for the conversion of nitrogen oxides, act as they are known in the art.

The second portion of the connecting element may at least partially protrude through the wall element, which facilitates attachment particularly when the second portion of the connecting element extends in extension of the hollow body. A simple way of fixing arises when the second

Section is formed by an internal thread and is fastened by means of a screw connection to the wall element.

It is possible to provide a seal between the body and the wall element in the region of the connecting element in order to prevent a leakage of the exhaust gas flow.

Further features and advantages of the invention will become apparent from the following description of several embodiments, taken in conjunction with the accompanying drawings. In these show:

- Figure 1 is a schematic sectional view of an exhaust gas treatment apparatus in which an assembly according to the invention can be used; - Figure 2 is a schematic sectional view of an assembly according to the invention with a body and a connecting element in a fragmentarily shown exhaust gas treatment device according to the invention;

- Figure 3 shows a second embodiment of an assembly according to the invention;

- Figure 4 shows a variant of the assembly shown in Figure 3;

- Figure 5 shows the assembly of Figures 3 and 4, mounted in a fragmentarily shown exhaust gas treatment apparatus according to the invention in a schematic sectional view; - Figure 6 shows a third embodiment of an assembly according to the invention;

- Figure 7 shows the assembly of Figure 6 in a fragmentarily shown exhaust gas treatment apparatus according to the invention in a schematic sectional view;

- Figure 8 shows an assembly according to the invention according to a fourth embodiment;

- Figure 9 shows the assembly of Figure 8 in a fragmentary exhaust gas treatment apparatus according to the invention in a schematic sectional view; and

FIGS. 10 and 11 are fragmentary exhaust gas treatment devices according to the invention, in which between body and

Wall element is a seal is inserted, in schematic sectional views.

FIG. 1 schematically shows an exhaust gas treatment device 10, for example a soot particle filter for a diesel engine of a passenger car. The exhaust treatment device 10 is arranged in an exhaust pipe (not shown) and is flowed through in the arrow direction by the exhaust gas. In a housing 12, usually made of a metal sheet, two perpendicular to the axial wall elements 14, 16 are used, which are partially provided with openings, so that the exhaust gas flow through the housing 12 from one side to another. Between the wall elements 14, 16 is a body 18 made of a gas-permeable, porous substrate arranged so that the exhaust gas must pass through at least one wall of the body 18 to pass from the inlet side of the housing 12 to the outlet side.

In the examples shown here, the body 18 is designed as a hollow body in the form of two cones or truncated cones inserted in opposite directions. However, it could also be in the form of one or more cylinders, truncated pyramids or simply as a block.

As a substrate for the body 18, porous metal bodies are used in the examples shown here, which consist for example of a metal foam, metal sponge or a metallic hollow spherical structure. The use of other porous substrates is also conceivable.

The attachment of the body 18 to the outflow-side wall element 16 is shown by way of example below. However, the technique can just as well on the attachment of the body on the upstream wall member 14 or of course on a completely different housing part in a different design

Exhaust treatment device 10 transferred.

2 shows a first embodiment of an exhaust gas treatment device with an assembly of a body 18 and a connecting element 22 is shown. In the region of the end facing the wall element 16 of the body 18, a first portion 20 of the connecting element 22 is embedded in the substrate of the body 18. The first section 20 here is a piece of pipe which is inserted through the wall of the body 18 transversely to the axial direction A, in which the body 18 extends. The area of the surface of the first portion 20 that is in contact with the

Substrate is, is structured so that the adhesion between the first portion 20 and the substrate of the body 18 is as good as possible. For this purpose, the surface can be perforated, for example, with many openings, corrugated and / or be provided with projections, depressions or grooves. Such or another suitable structuring can be provided for each connecting element presented here. The first portion 20 of the connecting element 22 is before the sintering of the

Body 18 embedded in the substrate and then sintered together with the body 18, wherein during sintering, a firm connection between the substrate of the body 18 and the first portion 20 of the connecting element 22 is formed.

Depending on the substrate used, the first portion 20 of the connecting element 22 may already be introduced into the matrix which is used to form the substrate, so that the substrate can perfectly adapt to the surface structure of the first portion 20. Alternatively, it is also possible, the first section 20 of the

Connecting element 22 to introduce after sintering in the substrate of the body 18, wherein also here a structured surface causes better adhesion and thus a better power transmission.

In this example, the connecting element 22 or its first section 20 is embedded in the axial direction A a distance from the end face 24 of the body 18 in the substrate.

Between the end face 24 and the wall member 16, a gap is left free, which is tuned to the thermal expansion coefficients of the body 18 and the housing 12 and the transmitted to the body 18 by the gas flow forces, so that the end face 24 is not possible on

Wall element 16 abuts.

A second section 26 of the connecting element 22 connects the first section 20 and thus the body 18 to the wall element 16.

In the example of the first embodiment, the second portion 26 is formed as a flexible angled plate, which is provided at one end with an opening and is placed over the tube of the first portion 20, where it is welded by means of welds 28 with this. Alternatively, the second portion 26 may of course also be soldered, glued or otherwise secured. At its other end, the second section 26 is fixed to the

Wall element 16 connected, also by means of a welding or soldering seam 28th or any other suitable method, such as gluing, screwing or riveting.

The flexibility of the second portion 26 is here chosen to be a displacement of the body 18 and the wall member 16 against each other, e.g. when absorbing forces due to gas flow or thermal expansion.

There are a plurality of connecting elements 22 distributed over the circumference of the body 18 and each separately attached to the wall element 16.

Figures 3 to 5 show a second embodiment of an assembly with a body 18 and a connecting element 122 and an exhaust gas treatment device with such an assembly.

In this example, the first portion 120 is formed of a first elongated sheet metal portion, while the second portion 126 consists of a further elongate sheet metal portion integrally connected to the first portion 120.

The first portion 120 is formed following the curvature of the body 18, which in this case is formed by a cone. In addition, the first portion 120 is still curled in itself and provided with two flaps 128 issued transversely to its direction of extension, as indicated schematically in FIG. In addition, the first portion 120 may be perforated with many small openings.

The entire first portion 120 is fully embedded in the substrate of the body 18 so that the surface of the portion 120 is in contact with the substrate everywhere. The second section 126 projects out of the body 18 in an extension of the first section 120 approximately in the axial direction A. The second section 126 is formed here flat and not structured. However, it could also have any suitable structure, for example, be curved in the same way as the first section. In the exhaust treatment device, the second portion 126 is inserted through a slot-shaped opening 130 in the wall member 16 and on the Side of the wall member 16 which faces away from the body 18, soldered or welded, as the reference numeral 28 indicate. The connecting element 122 acts as a tie rod.

Alternatively, it would also be possible (not shown here) to use a circumferentially circumferential tube instead of individual elongated plates, wherein the portion of the tube which is embedded in the substrate of the body 18, forms the first portion of the connecting element and can be structured, as just has been described, while one or more protruding from the body portions form the second portion of the connecting element and are connected to the wall member 16 in a suitable manner.

The third embodiment shown in Figs. 6 and 7 is similar to the second one just described. In contrast to that, the connecting element 222 is made of a wire mesh. Again, the first portion 220 is bent according to the curvature of the body 18, while the second portion 226 is planar. The attachment to the wall element 16 takes place in analogy to the embodiment just described. The wire mesh of the first section 220 allows intimate connection between the substrate of the body 18 and the first portion of the connecting element 222, particularly if the wire mesh is already introduced into the body 18 prior to sintering.

In the example shown, the wire mesh is a single-ply fabric in which individual wires pass continuously through the entire length of the connecting element 222. This ensures a very good and very high power transmission. In the examples just shown, the end face 24 of the body 18 again has a small distance from the wall element 16.

FIGS. 8 and 9 show a fourth embodiment of an assembly or an exhaust gas treatment device.

Here, the connecting element 322 is designed in the form of a threaded sleeve with an internal thread. Several of these threaded sleeves, nine in the present example, are on the circumference of the body 18 at the

Front side 24 arranged, in this case so that the threaded sleeves in Substantially flush with the end face 24 are embedded in the body 18. The first portion 320 is formed by the outer surface of the threaded sleeves embedded in the body 18.

The second section 326 is formed here by the internal thread. In this a screw or bolt 330 is screwed, as indicated in Figure 9.

This embodiment is not limited to the use of a threaded sleeve. The connector 322 could be e.g. be formed in the form of a sheet-like component with one or more internal threads integrated therein.

The screw or bolt 330 may be soldered or welded to the wall member 16, as indicated by reference numeral 28. In this example, an opening 130, this time in the form of a round or oblong hole, is again provided in the wall element 16, through which in this case the screw or the bolt 330 extends to contact the connecting element 322.

The surface of the first portion 320 is preferably structured as described for the first embodiment.

FIGS. 10 and 11 show, for two different examples, the arrangement of a seal 350 between the end face 24 of the body 18 and the wall element 16. The seal 350 is circumferentially formed over the circumference of the body 18 and surrounds the end face 24 of the body

18 seen in the radial direction on both sides.

In the case of FIG. 10, which shows an assembly according to the second embodiment, the second portion 126 extends through the seal 350.

In the example of FIG. 11, which shows an assembly according to the first embodiment, the seal 350 lies between the end face 24 of the body 18 and the wall element 16. The seal 350 serves to exclude a leakage of the exhaust gas flow by moving the body 18 relative to the body Wall element 16 seals and thus forces the exhaust stream to pass through a wall of the body 18 to pass through the housing 12.

The seal 350 has some inherent flexibility to allow movement of body 18 and wall member 16 against each other to some extent.

As a seal, for example, a sealant of silicate fibers, a Blähmatte, a single-ply wire mesh or a wire mesh, which is combined with integrated fabric or fibers are used.

The gasket 350 is placed between the body 18 and the body during assembly of the exhaust treatment device 10

Wall element 16 inserted and can be over the second section of the

Fix the connection element. Such a seal may be provided in all described embodiments.

All features of the individual embodiments can be exchanged with each other and combine with each other, at the discretion of the skilled person. Likewise, the technique presented here can be applied to all types of bodies.

Claims

claims

An assembly, in particular for an exhaust gas treatment device for treating exhaust gases of an internal combustion engine, comprising a body (18) at least partially made of a gas-permeable substrate, and at least one connecting element (22; 122; 222; 322) for connecting the body (18 ) having a wall member (16) of a housing (12), said connector (22; 122; 222; 322) having a first portion (20; 120; 220; 320) embedded in the substrate of the body (18) ,

2. Assembly according to claim 1, characterized in that the first

Section (20; 120; 220; 320) of the connecting element (22; 122; 222; 322) is sintered into the substrate.

3. Assembly according to one of the preceding claims, characterized in that the outer surface of the first portion (120; 220; 320) is completely enclosed by the substrate of the body (18).

An assembly according to any one of the preceding claims, characterized in that the first portion (20; 120; 220; 320) of the connecting element (22; 122; 222; 322) is embedded at an axial end of the body (18).

5. Assembly according to one of the preceding claims, characterized in that the first portion (20) of the connecting element (22) is designed in the form of a tube.

6. Assembly according to one of claims 1 to 4, characterized in that the connecting element (122) is designed in the form of an elongated metal strip.

7. Assembly according to one of claims 1 to 4, characterized in that the connecting element (222) consists of a wire mesh.

8. Assembly according to one of claims 1 to 4, characterized in that the first portion (320) of the connecting element (322) consists of a threaded bushing.

9. An assembly according to claim 8, characterized in that a plurality of over the circumference of the body (18) distributed threaded bushings are provided.

10. Assembly according to one of the preceding claims, characterized in that the first portion (120) of the connecting element (122) has at least one protruding tab.

An assembly according to any one of the preceding claims, characterized in that the surface of the first portion (20; 120; 220; 320) of the connecting element (22; 122; 222; 322) has a structure which ensures a firm connection to the substrate ,

12. An assembly according to claim 11, characterized in that the first

Section (20; 120; 220; 320) of the connecting element (22; 122; 222; 322) has a plurality of openings.

13. Assembly according to one of the preceding claims, characterized in that the body (18) is a hollow body, in particular a cone, truncated cone or cylinder.

14. Assembly according to one of the preceding claims, characterized in that the substrate is a wire mesh, a metal foam, a metal sponge or a metallic hollow spherical structure.

An assembly according to any one of the preceding claims, characterized in that the connecting element (22; 122; 222; 322) has a second portion (26; 126; 226; 326) which can be fixedly connected to the wall element (16).

16. An assembly according to claim 15, characterized in that the second portion (26) of the connecting element (22) is designed in the form of a flexible angled sheet.

17. An assembly according to claim 15, characterized in that the second portion (326) is formed as an internal thread.

18. exhaust treatment device with an assembly according to any one of the preceding claims and with a housing (12) having at least one wall element (16), the body (18) being received in the housing (12) and exhaust gas flowing through it, and wherein the connecting element (22; 122; 222; 322) has a second section

(26; 126; 226; 326) connecting the body (18) to the wall member (16).

An exhaust treatment device according to claim 18, characterized in that the second portion (26; 126; 226) of the connecting element (22; 122; 222) is fixed to the wall element (16) by welding or soldering.

20. Exhaust treatment device according to one of claims 18 to 19, characterized in that the second portion (126; 226) of the connecting element (122; 222) at least partially protrudes through the wall element (16).

21. exhaust treatment device according to claim 18, characterized in that the second portion (326) is formed by an internal thread and by means of a screw on the wall element (16) is attached.

22. Exhaust treatment device according to one of claims 18 to 20, characterized in that between the body (18) and the wall element (16) in the region of the connecting element (22; 122; 222; 322) a seal (350) is provided.