EP2246536A1 - Casing for an exhaust gas cleaning device and manufacturing method - Google Patents

Abstract

The housing (2) has a jacket (6) closed in a circumferential direction i.e. longitudinal/axial direction (3), for mounting an exhaust gas-treating element (5). The jacket is moved over an axial end (22) into a ring body (8). The ring body is closed in the circumferential direction for connecting the housing to a component of an exhaust system of an internal combustion engine. The jacket and the ring body are made with different wall thicknesses (12-14) by rolling a single sheet steel billet in the circumferential direction and connecting abutting edges of the billet together. An independent claim is also included for a process for manufacturing an exhaust gas-treating device housing of an exhaust system of an internal combustion engine.

Description

The present invention relates to a housing for an exhaust gas treatment device of an exhaust system of an internal combustion engine. The invention also relates to a method for producing such a housing.

Housing of exhaust treatment facilities, such. For example, catalysts and particulate filters, as a rule, have a jacket closed in the circumferential direction for receiving at least one exhaust gas treatment element. This jacket can transition at least one axial end into a circumferentially closed, for example, funnel-shaped annular body, with which the housing can be connected to another component of the exhaust system. Furthermore, it is customary to produce the jacket by rolling from a sheet metal blank, while the respective annular body is preferably produced by deep drawing. The rolled and welded at its abutting edges jacket is then axially connected to the ring body, preferably by means of a weld. This conventional procedure for producing such a housing is associated with a relatively large amount of effort.

The present invention is concerned with the problem of providing an improved embodiment for a housing of the aforementioned type or for an associated manufacturing method, which is characterized in particular by the fact that the housing can be produced comparatively inexpensively. This problem is solved according to the invention by the subject matters of the independent claims. Advantageous embodiments are the subject of the dependent claims.

The invention is based on the general idea to produce the shell and at least one annular body by using a so-called tailored blanks by rolling. Such a tailored blank is a sheet metal blank, which is characterized in that it has at least two regions of different materials and / or different wall thicknesses. When rolling the tailored blanks can thus shell and ring body of the housing can be formed simultaneously, with sheath and ring body of different materials and / or can be realized with different wall thicknesses. This approach uses the knowledge that, for example, the jacket is only exposed to comparatively low loads, while the at least one annular body is exposed to much higher mechanical loads. By reducing the wall thickness of the shell relative to the wall thickness of the ring body can be here significant savings in terms of material, weight and cost realized. Furthermore, it is particularly easy to realize ferritic and austenitic sections on the housing, which has an advantageous effect in particular on the service life of the housing. For example, the sheath may be made from an austenitic portion of the sheet metal blank while the ring body is made from a ferritic portion of the blank sheet, or vice versa. The use of a Rollierverfahrens for producing the housing allows a particularly simple adaptation to different rolling parameters on the one hand for rolling the shell and on the other hand for rolling the respective ring body. Thus, the respective housing can be realized particularly inexpensive.

In an advantageous embodiment, the respective annular body can be configured as a funnel. As a result, an inlet funnel and / or a discharge funnel of the housing can be integrally formed on the casing and yet have different material properties or strength values. As a result, an adaptation to the different functions of jacket and ring body or funnel can be optimized. At the same time a comparatively inexpensive manufacturability is achieved by the procedure according to the invention.

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention.

Preferred embodiments of the invention are illustrated in the drawings and will be described in more detail in the following description, wherein like reference numerals refer to the same or similar or functionally identical components.

Fig. 1 bis 3

jeweils einen stark vereinfachten Längsschnitt durch einen Teil einer Abgasbehandlungseinrichtung, bei unterschiedlichen Ausführungsformen,

Fig. 4

eine Draufsicht auf eine Blechplatine in einem Ausgangszustand,

Fig. 5 bis 8

Seitenansichten der Blechplatine entsprechend einer Blickrichtung V in Fig. 4, bei unterschiedlichen Phasen eines Herstellungsprozesses.

Show, in each case schematically,

Fig. 1 to 3

in each case a greatly simplified longitudinal section through a part of an exhaust gas treatment device, in different embodiments,

Fig. 4

a top view of a sheet metal blank in an initial state,

Fig. 5 to 8

Side views of the sheet metal blank according to a line of sight V in Fig. 4 , at different stages of a manufacturing process.

According to the Fig. 1 to 3 For example, an exhaust treatment device 1 includes a housing 2 that is closed in the circumferential direction. This circumferential direction refers to a longitudinal or axial direction 3, which extends parallel to a longitudinal central axis 4 of the housing 2. The exhaust gas treatment device 1 may, for example, be a catalytic converter or a particle filter. Accordingly, at least one exhaust gas treatment element 5 is arranged in the housing 2, which may, for example, be a catalyst element or a particle filter element. The exhaust gas treatment device 1 is provided for use in an exhaust system of an internal combustion engine, wherein the internal combustion engine may preferably be located in a motor vehicle.

The housing 2 comprises a jacket 6, which is closed in the circumferential direction and which is designed to receive the at least one exhaust gas treatment element 5. For this purpose, the jacket 6 encloses the respective exhaust gas treatment element 5 coaxially. The respective exhaust gas treatment element 5 can be positioned in the jacket 6 by means of at least one bearing mat 7. The housing 2 further comprises at least one ring body 8, 9. In the examples shown, two such ring body 8, 9 are provided in each case. The respective ring body 8, 9 is closed in the circumferential direction and serves to connect the housing 2 to another component of the exhaust system can. The jacket 6 passes at its axial ends in each case in one of these ring body 8, 9 via.

The jacket 6 and the ring body 8, 9 are made by rolling from a single, in Fig. 4 produced sheet metal blank 10, wherein abutting edges 11 of the sheet metal blank 10 in the finished housing 2 are interconnected. The jacket 6 and at least one of the annular body 8, 9 differ from each other by different materials or by different wall thicknesses or by different materials and different wall thicknesses.

In the examples of Fig. 1 to 3 is a wall thickness 12 of the shell 6 significantly smaller than a wall thickness 13 of the ring body 8 shown on the left and smaller than a wall thickness 14 of the ring body 9 shown on the right. In the examples of Fig. 1 and 3 are the wall thicknesses 13, 14 of the two ring body 8, 9 the same size. In contrast, at the in Fig. 2 shown embodiment, the wall thickness 13 of the ring body 8 shown on the left smaller than the wall thickness 14 of the ring body 9 shown on the right. In addition, the jacket 6 and the respective ring body 8, 9 may be made of different materials. For example, the jacket 6 may be made of an austenitic steel sheet, while the ring members 8, 9 are made of a ferritic steel sheet.

At the in Fig. 1 Shown embodiment, both ring body 8, 9 are each configured as a funnel. The one annular body 8 or 9 then forms an inlet funnel, while the other funnel 9, 8 then forms a discharge funnel. Fig. 2 shows an embodiment in which the one annular body 8 is designed as a cylindrical sleeve, while the other annular body 9 is designed as a funnel. Fig. 3 shows an embodiment in which both annular bodies 8, 9 are each designed as cylindrical sleeves.

The following is based on the Fig. 4 to 8 a preferred method for producing the housing 6 explained in more detail.

Fig. 4 shows a plan view of a sheet metal blank 10, with the help of the housing 2 is to be produced. Visible, the metal sheet 10 has a jacket portion 6 ', which is provided to form the shell 6, and at least one annular body portion 8', 9 '; which is provided for forming the respective annular body 8, 9. The sheet metal blank 10 is a so-called tailored blank and is characterized in that said areas 6 ', 8', 9 'can be designed differently. They differ, for example, by their wall thicknesses and / or by their materials. In the example, the metal sheet 10 has a smaller wall thickness in the jacket region 6 'than in the annular body regions 8', 9 '. In principle, these regions 6 ', 8', 9 'of different wall thickness can be formed during roll forming of the sheet metal blank 10. However, an embodiment in which roll-formed sheets 15, 16, 17 of different wall thicknesses are welded together by welds 18, 19 at their lateral longitudinal edges in order to produce the respective sheet metal blank 10 is preferred. Industrially, the individual partial plates 15, 16, 17 are provided in the form of sheet metal strips on corresponding rollers or coils. From these coils, the metal sheets are unrolled, along the welds 18, 19 connected to each other, whereby a web is formed, which can also be rolled up on a roll. From the latter role can then roll a metal sheet and separate to the individual sheet metal blanks 10, whereby the abutting edges 11 arise.

In the in the 4 and 5 shown initial state, the sheet metal blank 10 extends in a plane. According to the Fig. 6 and 7 the sheet metal blank 10 is roll formed, that is formed by rolling, wherein the roll forming is performed with respect to the longitudinal center axis 4 of the housing 2 to be produced. Accordingly, the shell portion 6 'during roll forming the shell 6, while the annular body portions 8', 9 'during roll forming the respective annular body 8, 9 form.

After roll forming lies in Fig. 7 shown state in which the abutting edges 11 are opposite to each other. Corresponding Fig. 8 the abutting edges 11 of the roll-formed sheet metal blank 10 are connected together. An appropriate connection is in Fig. 8 denoted by 20. This connection 20 is preferably a weld. Alternatively, it is also possible to design the connection 20 as a flared connection. Suitably, the blank of the sheet metal blank 10 is selected so that after the roll forming of the sheet metal blank 10, a straight-line butt joint 20 is formed. Furthermore, the rolling method is preferably carried out such that this butt joint 20 extends only axially, ie parallel to the longitudinal central axis 4.

The housing 2 thereby has a single butt joint 20 which extends in the axial direction over the entire housing 2 or over the casing 6 and over the respective annular body 8, 9 formed thereon.

According to a preferred embodiment, the sheath 6 and the annular body 8, 9 are finally formed after the production of the butt joint 20. This final shaping includes, for example, forming at least one of the ring bodies 8, 9 into a funnel. The end molding may additionally or alternatively also include the molding of a flange 21, as in the Fig. 1 and 2 is shown. The flange 21 is designed circumferentially in the circumferential direction. Additionally or alternatively it can be provided, before the end molding of the shell 6 and the respective annular body 8, 9, the at least one exhaust gas treatment element 5 together with the respective bearing mat 7 in to use the housing 2 or in the jacket 6, so-called Canning. Only by the final shaping of the shell 6, a desired bias in the respective bearing mat 7 is realized in order to fix the respective exhaust treatment element 5 properly in the jacket 6 and in the housing 2. Before inserting the respective exhaust gas treatment element 5, it is corresponding Fig. 1 also possible to install an axial end stop 22 in the housing 2, in particular welding. This end stop 22 supports the respective exhaust gas treatment element 5 in the axial direction 3. When the ring bodies 8, 9 are finished, they can be adapted in terms of their dimensions to connection elements to which they are to be connected when the exhaust gas treatment device 1 is installed in an exhaust system. As a result of this downstream final shaping, it is particularly easy to adapt the housing 2 to comparatively large dimensional tolerances of the exhaust gas treatment elements 5, which may be, for example, ceramic monoliths.

After the final molding it can be done accordingly Fig. 2 be provided to grow a probe 23 to the housing 2, here to the right annular body. 9

In all embodiments shown here, the sheet metal blank 10 is designed or the roll forming of the sheet metal blank 10 is performed so that the housing 2, the respective larger wall thickness 13, 14 applies only to the outside. As a result, a uniform inner cross-section is realized for the interior of the housing 2 for the section of the housing 2 accommodating the respective exhaust-gas treatment element 5, which facilitates the insertion of the respective exhaust-gas treatment element 5. In particular, the respective exhaust-gas treatment element 5 can extend in the axial direction into at least one of the annular bodies 8, so that, as in FIGS Fig. 1 to 3 indicated, between the respective annular body 8, 9 and the respective dispensing treatment element 5 may result in an axial overlap.

Claims (11)

Housing for an exhaust gas treatment device (1) of an exhaust system of an internal combustion engine, - With a circumferentially closed jacket (6) for receiving at least one exhaust gas treatment element (5) merges at least one axial end in a circumferentially closed annular body (8, 9), with which the housing (2) to another component of Exhaust system can be connected, - wherein the jacket (6) and the at least one annular body (8, 9) of a single sheet metal blank (10) by rolling the sheet metal blank (10) in the circumferential direction and by connecting abutting edges (11) of the sheet metal blank (10) are made - Wherein the jacket (6) and the at least one annular body (8, 9) by different materials and / or different wall thicknesses (12, 13, 14) differ from each other. Housing according to claim 1,
characterized,
in that the housing (2) has a single butt joint (20) which extends in the axial direction over the jacket (6) over the at least one annular body (8). Housing according to claim 2,
characterized,
that the butt joint (20) only extends axially. Housing according to claim 2 or 3,
characterized,
that the butt joint (20) is designed as a welded connection or as a flared connection. Housing according to one of claims 1 to 4,
characterized,
that the ring body (8, 9) is designed as a funnel. Method for producing a housing (2) for an exhaust-gas treatment device (1) of an exhaust system of an internal combustion engine, - In which a sheet metal blank (10) is produced or used, which has at least two board sections (6 ', 8', 9 '), which differ with respect to material and / or wall thickness, - In which the sheet metal blank (10) is formed by rolling so that one of the board sections (6 ') forms a jacket (6) of the housing (2) and the at least one other board section (8', 9 ') at least one at one axial end of the shell (6) arranged annular body (8, 9), - At the abutting edges (11) of the roll-formed board (10) are interconnected. Method according to claim 6,
characterized,
in that the jacket (6) and / or the at least one ring body (8, 9) are finally shaped after the production of the butt joint (20). Method according to claim 7,
characterized,
in that the at least one ring body (6, 8) is provided, after the production of the butt joint (20), with a peripheral flange (21). Method according to claim 7 or 8,
characterized,
in that the at least one ring body (8, 9) is formed into a funnel after producing the butt joint (20). Method according to one of claims 7 to 9,
characterized,
in that at least one exhaust-gas treatment element (5) is inserted into the housing (2) before the end-molding of the jacket (6) and / or of the at least one annular body (8, 9). Method according to one of claims 6 to 10,
characterized,
that the roll forming in the sheet metal blank (10) with board sections (6 ', 8', 9 ') of different wall thickness is performed so that the housing (2) the larger wall thickness applies only to the outside.

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