SHEATHING ARRANGEMENT AND PROCESS FOR MANUFACTURING A SHEATHING ARRANGEMENT FOR AN EXHAUST SYSTEM OF AN INTERNAL COMBUSTION ENGINE

Abstract

A sheathing arrangement for an exhaust system of an internal combustion engine includes at least one sheathing element (18) with a sheathing element shell (19). On an inner side (30) of the sheathing element shell (19) insulation material (38) overlaps the inner side (30) in at least some areas. The inner side is to be positioned facing toward a component of an exhaust system (10), which component is to be sheathed. The insulation material (38) is fixed to the sheathing element shell (19) by means of at least one fastening element (40) passing through the sheathing element shell (19) and the insulation material (38).

Claims

1. A sheathing arrangement for an exhaust system of an internal combustion engine, the sheathing arrangement comprising: at least one sheathing element comprising a sheathing element shell having a shell inner side configured to be positioned facing toward a component of the exhaust system, which component is to be sheathed; insulation material overlapping the shell inner side in at least some areas; and at least one fastening element passing through the sheathing element shell and the insulation material and fixing the insulation material to the sheathing element shell.

2. The sheathing arrangement in accordance with claim 1, wherein the sheathing element shell has a fastening element receiving area in association with the at least one fastening element fixing the insulation material to the sheathing element shell, the fastening element receiving area having a wall thickness that is reduced, in a shell area enclosing the fastening element receiving area, in relation to a base wall thickness of the sheathing element shell.

3. The sheathing arrangement in accordance with claim 2, wherein: the wall thickness of the fastening element receiving area of the sheathing element shell is in a range of 0.2 mm to 0.4 mm; and the base wall thickness of the sheathing element shell is in a range of 0.4 mm to 0.6 mm.

4. The sheathing arrangement in accordance with claim 2, wherein the fastening element receiving area is formed by a recess provided on an outer side of the sheathing element shell, which outer side is to be positioned facing away from the component to be sheathed.

5. The sheathing arrangement in accordance with claim 1, wherein: the at least one fastening element has a U-shaped configuration with two U-legs and a connection web connecting the two U-legs; the two U-legs traverse the sheathing element shell and the insulation material; each of the U-legs has a section protruding on an insulation inner side of the insulation material, which insulation inner side is to be positioned facing toward a component to be sheathed, with each section bent as a bent section such that at least one of the bent sections adjoins the insulation inner side of the insulation material; and a connection web connecting the two U-legs adjoins a shell outer side of the sheathing element shell, which shell outer side is to be positioned facing away from the component to be sheathed.

6. The sheathing arrangement in accordance with claim 1, wherein: the insulation material has a mat configuration; or the sheathing arrangement comprises at least one additional fastening element to provide a plurality of fastening elements with the insulation material fixed to the sheathing element shell by means of the plurality of fastening elements; or the insulation material has a mat configuration and the sheathing arrangement comprises at least one additional fastening element to provide a plurality of fastening elements with the insulation material fixed to the sheathing element shell by means of the plurality of fastening elements.

7. The sheathing arrangement in accordance with claim 1, wherein the sheathing element shell is a shaped sheet metal part.

8. A process for manufacturing a sheathing arrangement for an exhaust system of an internal combustion engine, wherein the sheathing arrangement comprises at least one sheathing element comprising a sheathing element shell having a shell inner side configured to be positioned facing toward a component of the exhaust system, which component is to be sheathed, insulation material overlapping the shell inner side in at least some areas, and at least one fastening element passing through the sheathing element shell and the insulation material and fixing the insulation material to the sheathing element shell, wherein the process comprises the steps of: forming the sheathing element shell; forming the insulation material to be arranged on the inner side of the sheathing element shell; arranging the insulation material on the shell inner side of the sheathing element shell; and fixing of the insulation material to the sheathing element shell by the at least one fastening element passing through the sheathing element shell and passing through the insulation material.

9. The process in accordance with claim 8, wherein the step of forming the sheathing element shell comprises forming the sheathing element shell with at least one fastening element receiving area with a wall thickness that is reduced, in a shell area enclosing the fastening element receiving area, in relation to a base wall thickness of the sheathing element shell.

10. The process in accordance with claim 9, wherein: the step of forming the sheathing element shell comprises the formation of the sheathing element shell with a base wall thickness in a range of 0.4 mm to 0.6 mm, and the formation of the sheathing element shell with a wall thickness in the range of 0.2 mm to 0.4 mm, in the at least one fastening element receiving area; or forming the sheathing element shell comprises forming the at least one fastening element receiving area on an outer side of the sheathing element shell, which outer side is to be positioned facing away from the component to be sheathed; or the step of forming the sheathing element shell comprises the formation of the sheathing element shell with a base wall thickness in a range of 0.4 mm to 0.6 mm, and the formation of the sheathing element shell with a wall thickness in the range of 0.2 mm to 0.4 mm, in the at least one fastening element receiving area and forming the sheathing element shell comprises forming the at least one fastening element receiving area on an outer side of the sheathing element shell, which outer side is to be positioned facing away from the component to be sheathed.

11. The process in accordance with claim 8, wherein the step of forming the sheathing element shell comprises forming the sheathing element shell as a shaped sheet metal part.

12. The process in accordance with claim 9, wherein: the step of forming the sheathing element shell comprises forming the sheathing element shell as a shaped sheet metal part; and the at least one fastening element receiving area is formed by material-displacing machining or/and material-removing machining of a sheet metal blank used for the formation of the sheathing element shell as a shaped sheet metal part.

13. The process in accordance with claim 8, wherein the forming the insulation material to be arranged on the inner side of the sheathing element shell comprises forming the insulation material as a mat configuration.

14. The process in accordance with 8, wherein: fixing of the insulation material to the sheathing element shell comprises providing the at least one fastening element as at least one U-shaped fastening element comprising two U-legs and a connection web connecting the two U-legs; the U-legs are pushed through the sheathing element shell and the insulation material so that the connection web connecting the two U-legs adjoins an outer side of the sheathing element shell, which outer side is to be positioned facing away from the component to be sheathed, and that the two U-legs protrude on an inner side of the insulation material, which inner side faces toward the component to be sheathed; and the two U-legs are bent to provide U-leg sections protruding on the inner side of the insulation material such that at least one of the U-leg sections adjoins the inner side of the insulation material.

15. The process in accordance with claim 8, wherein no other steps for fixing the insulation material to the sheathing element shell are carried out aside from the step of fixing the insulation material to the sheathing element shell by at least one fastening element.

16. An exhaust system comprising at least one component sheathed and a sheathing arrangement, the sheathing arrangement comprising: at least one sheathing element comprising a sheathing element shell having a shell inner side configured to be positioned facing toward a component of the exhaust system, which component is to be sheathed; insulation material overlapping the shell inner side in at least some areas; and at least one fastening element passing through the sheathing element shell and the insulation material and fixing the insulation material to the sheathing element shell.

17. The exhaust system in accordance with claim 16, wherein: the sheathing element shell has a fastening element receiving area in association with the at least one fastening element fixing the insulation material to the sheathing element shell, the fastening element receiving area having a wall thickness that is reduced, in a shell area enclosing the fastening element receiving area, in relation to a base wall thickness of the sheathing element shell; and the fastening element receiving area is formed by a recess provided on a shell outer side of the sheathing element shell, which outer side is to be positioned facing away from the component to be sheathed.

18. The exhaust system in accordance with claim 16, wherein: the insulation material has a mat configuration; or the sheathing arrangement comprises at least one additional fastening element to provide a plurality of fastening elements with the insulation material fixed to the sheathing element shell by means of the plurality of fastening elements; or the insulation material has a mat configuration and the sheathing arrangement comprises at least one additional fastening element to provide a plurality of fastening elements with the insulation material fixed to the sheathing element shell by means of the plurality of fastening elements.

19. The exhaust system in accordance with claim 16, wherein the exhaust system is formed by a process comprising the steps of: forming the sheathing element shell; forming the insulation material to be arranged on the inner side of the sheathing element shell; arranging the insulation material on the shell inner side of the sheathing element shell; and fixing of the insulation material to the sheathing element shell by the at least one fastening element passing through the sheathing element shell and passing through the insulation material.

20. The exhaust system in accordance with claim 19, wherein: fixing of the insulation material to the sheathing element shell comprises providing the at least one fastening element as at least one U-shaped fastening element comprising two U-legs and a connection web connecting the two U-legs; the U-legs are pushed through the sheathing element shell and the insulation material so that the connection web connecting the two U-legs adjoins an outer side of the sheathing element shell, which outer side is to be positioned facing away from the component to be sheathed, and that the two U-legs protrude on an inner side of the insulation material, which inner side faces toward the component to be sheathed; and the two U-legs are bent to provide U-leg sections protruding on the inner side of the insulation material such that at least one of the U-leg sections adjoins the inner side of the insulation material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In the drawings:

[0029] FIG. 1 is a partial area of an exhaust system with a sheathing arrangement sheathing a component (shown schematically in dashed line) of the exhaust system;

[0030] FIG. 2 is a side view of a sheathing shell element of the sheathing arrangement from FIG. 1;

[0031] FIG. 3 is a detail sectional view of a sheathing shell element connected to insulation material; and

[0032] FIG. 4 is another detail sectional view of the sheathing shell element connected to the insulation material.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0033] Referring to the drawings, a partial area of an exhaust system of an internal combustion engine, which exhaust system is generally designated by 10, can be seen in FIG. 1. The exhaust system 10 comprises between tubular exhaust gas-carrying elements 12, 14 a component M, e.g., a muffler, which is enclosed by a sheathing arrangement 16 and therefore cannot be seen, such that it is shown in FIG. 1 in dashed line.

[0034] The sheathing arrangement 16 shown in FIG. 1 comprises a plurality of sheathing elements 18, 20, 22, 24, 26, 28, which are associated with each other in pairs. Each of the sheathing elements 18, 20, 22, 24, 26, 28 forms with the respective sheathing element complementary to it an area of the sheathing 16, which area of sheathing 16 fully encloses the exhaust system 10 or the component to be sheathed, wherein the sheathing elements 18, 20 and 22, 24 and 26, 28, which are complementary to each other, can be permanently connected to each other, for example, by flanging and/or by connection in substance, e.g., welding in edge areas adjacent to one another.

[0035] To achieve an improved shielding of the component of the exhaust system 10, which component is to be sheathed, preferably mat-like insulation material is preferably provided on one side of a respective sheathing element shell, which side is associated with the component to be sheathed, in case of all the sheathing elements 18, 20, 22, 24, 26, 28. This insulation material, comprising, for example, one or more layers of fiber material or foamed material, is held in a stable manner between the respective sheathing element shell of the sheathing elements 18, 20, 22, 24, 26, 28 and the sheathed component in the assembled state shown in FIG. 1.

[0036] Before assembly of the exhaust system 10, it must, however, be ensured that a sheathing element shell of a respective sheathing element 18, 20, 22, 24, 26, 28 and the insulation material 38 provided on it be held together in order to guarantee that during the assembly or even after the assembly, the insulation material has the position intended for it in relation to the associated sheathing element shell, on the one hand, and in relation to the component to be sheathed, on the other hand.

[0037] In order to guarantee this defined position, the insulation material is fixed by means of at least one fastening element to the associated sheathing element in case of at least one, and preferably each of the sheathing elements 18, 20, 22, 24, 26, 28. This is illustrated in FIGS. 3 and 4 in reference to the sheathing element 18 shown in FIG. 2 or the sheathing element shell 19 thereof. The following explanation thus likewise also applies to the bonding of a respective insulation material in case of the other sheathing elements 20, 22, 24, 26, 28.

[0038] At least one fastening element receiving area 32 is provided on the sheathing element shell 19 of the sheathing element 18. This fastening element receiving area 32 is formed by a recess 36 being formed on an outer side 34 of the sheathing element shell 19, which outer side is to be positioned facing away from the component to be sheathed. This recess 36 may be formed during the manufacture of the sheathing element shell 19 during the shaping of a sheet metal blank by material being displaced by using a corresponding shaping tool where a fastening element receiving area 32 or a recess 36 shall be formed. This may take place in the course of the shaping of the sheet metal blank to obtain the shape of the sheathing element shell 19 shown in FIG. 2, so that no additional operation is necessary. As an alternative, the recess 36 may be formed by a corresponding deforming tool before or after the shaping of the sheet metal blank to obtain the desired shape of the sheathing element shell 19. As an alternative or in addition, it is possible to form such a recess 36 by means of a material-removing operation.

[0039] For manufacturing the sheathing material shell 19, for example, sheet metal material with a base wall thickness G in the range of about 0.5 mm may be used. In the area of a recess 36 shown in an enlarged view in FIG. 4 or in the fastening element receiving area 32 having the recess 36, the wall thickness W may be about 0.3 mm after forming the recess 36.

[0040] After one or more such fastening element receiving areas 32 have been formed in the sheathing element shell 19 and the insulation material 38 provided in a mat-like configuration was positioned on the inner side 30 of the sheathing element shell 19, the insulation material 38 is fixed by means of a fastening element 40, which has, for example, the clamp-like configuration shown, to the sheathing element shell 19 in the fastening element receiving area 32 or in each fastening element receiving area 32. The fastening element 40, which is clamp-like, i.e., provided with an essentially U-shaped structure is pushed with its two U-legs 42, 44 from the outer side 34 in the area of a recess 36 through the sheathing element shell 19 and the insulation material 38 positioned on the inner side 30 of the sheathing element shell 19. Since the sheathing element shell 19 is provided with a comparatively smaller wall thickness W in the fastening element receiving area 32 or in each fastening element receiving area 32, it is not necessary to use fastening elements 40 with excessively large dimensions in order to guarantee that the U-legs 42, 44 of the clamp-like fastening element 40 are not deformed during the operation of the pushing through the sheathing element shell 19.

[0041] After pushing the fastening element 40 through the sheathing element shell 19 and the insulation material 38, the U-legs 42, 44 are preferably bent toward one another, wherein, as can be seen in FIG. 3, the insulation material 38, which is, in principle, very flexible, is pressed against the inner side 30 of the sheathing element shell 19 and in the process is compressed. The sections 48, 50 of the U-legs 42, 44, which sections are bent toward one another, can occupy different positions in relation to one another in this state. FIG. 3 shows a state, in which the bent section 50 of the U-leg 44 overlaps the bent section 48 of the U-leg 42 on the side thereof, which side is facing away from the insulation material 38, so that essentially only the bent section 48 of the U-leg 42 touches the insulation material 38. FIG. 4 illustrates a state, in which the two bent sections 48, 50 of the U-legs 42, 44 are located next to one another and overlapping one another. Provisions could also be made, in principle, for the U-legs 42, 44 to be dimensioned such that the sections 48, 50, which are bent toward one another and adjoin the insulation material 38 on the inner side 46 of the insulation material 38, extend toward one another, but do not overlap one another. The sections 48, 50 could also be bent away from one another.

[0042] The provision of the recess 36 of a respective fastening element receiving area 32 on the outer side 34 of the sheathing element shell 19 has the advantage that after the insertion of a fastening element 40, a connection web 52 connecting the two U-legs 42, 44 on the outer side 34 of the sheathing element shell 19 is, for example, essentially entirely received in the recess 36, and thus does not protrude in the outwards direction.

[0043] By using such deformable fastening elements made, for example, of metallic material, it is possible to fix the insulation material to the respective associated sheathing element shell in a simple and reliably effective manner, so that it is guaranteed for a mounting operation to be carried out later for sheathing a component of an exhaust system that the insulation material retains its position intended for this. Additional steps, e.g., the bonding of the insulation material with the respective associated sheathing element shell, are not necessary.

[0044] While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.