MUFFLER

Abstract

A muffler for an exhaust system for an internal combustion engine includes a muffler housing having a circumferential wall surrounding a muffler interior, at least one compensation partition wall arranged in the muffler interior, and at least one exhaust pipe passing through at least one compensation partition wall in the region of a compensation pipe opening formed therein. The compensation pipe opening has a compensation opening internal dimension transverse to an opening central axis of the compensation pipe opening in at least one compensation opening longitudinal direction orthogonal to the opening central axis. The exhaust pipe passing through the compensation pipe opening has a pipe external dimension in the compensation opening longitudinal direction. The compensation opening internal dimension is greater than the pipe external dimension in the compensation opening longitudinal direction.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority of German patent application no. 10 2023 127 468.6, filed Oct. 9, 2023, the entire content of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a muffler for an exhaust system of an internal combustion engine.

BACKGROUND

A muffler of this type generally has a muffler housing with a circumferential wall elongated in a direction of a muffler longitudinal axis, surrounding the muffler longitudinal axis and radially outwardly delimiting a muffler interior and having an end wall in each of the two axial end regions of the circumferential wall, axially delimiting the muffler interior. The circumferential wall can be formed, for example, as a tubular body formed by winding a sheet-metal part, to the two axial ends of which the end walls formed as separate sheet-metal parts can be attached. In an alternative configuration, the muffler housing can, for example, be built up from two housing shells, each of which forms part of the circumferential wall and part of each end wall.

In order to subdivide the muffler interior into different chambers contributing to the silencing action, one or more partition walls generally supported on the circumferential wall in its outer circumferential region are provided in the muffler interior. In addition, one or more exhaust pipes passing through one or more such partition walls are provided in the muffler interior in the region of respective pipe openings. To introduce exhaust gas into the muffler interior and to discharge exhaust gas from the muffler interior, at least one exhaust pipe can be led through a pipe opening formed in the circumferential wall and/or at least one exhaust pipe can be led through a pipe opening formed in an end wall.

SUMMARY

An object of the present disclosure is to provide a muffler for an exhaust system of an internal combustion engine, the structure of which permits simplified assembly.

According to the disclosure, this object is, for example, achieved by a muffler for an exhaust system of an internal combustion engine, including a muffler housing with a circumferential wall surrounding a muffler interior, at least one compensation partition wall arranged in the muffler interior, and at least one exhaust pipe passing through at least one compensation partition wall in the region of a compensation pipe opening formed therein, wherein the compensation pipe opening has a compensation opening internal dimension transverse to an opening central axis of the compensation pipe opening in at least one compensation opening longitudinal direction orthogonal to the opening central axis, and the exhaust pipe passing through the compensation pipe opening has a pipe external dimension in the compensation opening longitudinal direction, wherein the compensation opening internal dimension is greater than the pipe external dimension in the compensation opening longitudinal direction.

As a result of providing such a compensation pipe opening accommodating an exhaust pipe, it is possible to arrange an exhaust pipe passing through such a compensation pipe opening in various positions with respect to the compensation partition wall in the compensation opening longitudinal direction. This avoids over-determination in the positioning of such an exhaust pipe if this also passes through other components of the muffler, for example other partition walls and/or an end wall or the circumferential wall. On the other hand, the variation in the positioning approved during assembly of an exhaust pipe associated with a compensation partition wall permits exact positioning with respect to another of these components through which it passes, for example the circumferential wall or an end wall. This exact positioning which can be achieved during assembly of these components can in turn contribute to avoiding further processing measures, such as cutting off a projecting pipe section.

For a structure that can be implemented simply, the exhaust pipe can have a substantially circular external circumferential contour.

In order to assist the variable positioning of an exhaust pipe in the region of a compensation pipe opening, it is proposed that the compensation pipe opening is formed in the manner of an elongated hole, wherein the compensation pipe opening is delimited in an exhaust pipe receiving portion by opening edge portions of the compensating partition wall which extend substantially in parallel, substantially rectilinearly to the compensation opening longitudinal direction. In the extension region of the exhaust pipe receiving portion, the exhaust pipe can then be positioned substantially freely without the production of restraints between the two opening edge portions.

In order to achieve a stable structure, an opening transverse dimension of the compensation pipe opening substantially orthogonal to the compensation opening longitudinal direction, at least in a compensation length region of the compensation pipe opening, can substantially correspond to a pipe external dimension of the exhaust pipe orthogonal to the compensation opening longitudinal direction.

For this purpose, provision can be made, for example, for a distance of the opening edge portions substantially transverse to the compensation opening longitudinal direction to substantially correspond to the pipe external dimension orthogonal to the compensation opening longitudinal direction.

A stable structure can further be assisted by the exhaust pipe being fixedly connected to the compensation partition wall in at least one fastening region located at a distance from a pipe longitudinal axis orthogonal to the compensation opening longitudinal direction.

For a mechanically stable and thermally resistant configuration, the exhaust pipe can be connected to the compensation partition wall in the at least one fastening region by a material connection, preferably welding.

Furthermore, for a stable configuration, provision can be made for the exhaust pipe to be fixedly connected to the compensation partition wall in at least one fastening region in the region of one of the opening edge portions.

The compensation partition wall can be formed as a shaped sheet-metal part, and the compensation pipe opening can be delimited by a passage formed in the compensation partition wall. The opening edge portions in the exhaust gas receiving portion of the compensation pipe opening can also be provided by this passage.

To introduce or discharge exhaust gas into and out of the muffler interior, at least one exhaust pipe passing through a compensation pipe opening can be formed as an angled pipe having a first pipe section passing through the compensation pipe opening and elongated in the direction of a first pipe longitudinal axis portion, and a second pipe portion engaging in a pipe opening of the circumferential wall and elongated in the direction of a second pipe longitudinal axis portion. In order to achieve a flush termination, for example, of this pipe portion with the circumferential wall, in particular in that region of the second pipe portion in which the latter passes through the circumferential wall or engages in the pipe opening in the circumferential wall, provision can also be made for the compensation opening longitudinal direction and the second pipe longitudinal axis portion to lie in one plane and/or to be substantially parallel.

If the first pipe longitudinal axis portion and the second pipe longitudinal axis portion are substantially orthogonal to each other, such an exhaust pipe can be provided as a substantially rectangular angled pipe.

In order to be able to achieve a defined silencing characteristic, it is proposed that at least two partition walls following each other in the direction of a muffler longitudinal axis are provided in the muffler interior, that at least one exhaust pipe passes through at least two partition walls in the region of a respective pipe opening, and that at least one, preferably each, of the partition walls is a compensation partition wall.

For a communication between the chambers separated by a compensation partition wall, also contributing to the silencing action, at least one, preferably a plurality of connecting openings can be formed in at least one, preferably each, compensation partition wall.

The disclosure further relates to exhaust systems for an internal combustion engine, including at least one muffler constructed according to the disclosure.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be described with reference to the drawings wherein:

FIG. 1 shows a perspective view of a muffler, illustrated with a partly opened housing;

FIG. 2 shows a partition wall of the muffler from FIG. 1;

FIG. 3 shows a detailed view of the partition wall from FIG. 2, if this is formed as a compensation partition wall; and,

FIG. 4 shows a basic partial longitudinal sectional view of the muffler from FIG. 1 with a partition wall formed as a compensation partition wall.

DETAILED DESCRIPTION

A muffler for an exhaust system of an internal combustion engine is designated generally by 10 in FIG. 1. The muffler 10 includes a muffler housing 12 having a circumferential wall 14 formed, for example, by winding a sheet-metal element and only partly illustrated in FIG. 1, and an end wall 20, 22 placed at a distance in the direction of a muffler longitudinal axis SL in each of two axial end regions 16, 18 of the circumferential wall 14. The circumferential wall 14 and the end walls 20, 22 delimit a muffler interior 24 through which exhaust gas can flow.

In the embodiment illustrated, five partition walls 26₁, 26₂, 26₃, 26₄, 26₅ are arranged in the muffler interior 24. The intermediate walls 26₁, 26₂, 26₃, 26₄, 26₅ are supported in a respective outer circumferential region of the inner side of the circumferential wall 14 and, between themselves and also in conjunction with the end walls 20, 22, form respective chambers 28₁, 28₂, 28₃, 28₄, 28₅, 28₆ of the muffler 10.

A plurality of exhaust pipes generally designated by 30 and likewise only partly illustrated extend in the interior of the muffler 10. The exhaust pipes 30 are used to introduce exhaust gas expelled by an internal combustion engine into the muffler 10 or into the interior 24 of the latter, to lead it through the various chambers 28₁, 28₂, 28₃, 28₄, 28₅, 28₆ and to discharge it again from the muffler 10. For example, exhaust pipes 30 can pass through the circumferential wall 14 and/or exhaust pipes 30 can pass through one or more partition walls 26₁, 26₂, 26₃, 26₄, 26₅ and one or both end walls 20, 22.

In this connection, it is emphasized that the muffler 10 is illustrated by way of example in FIG. 1. With regard to the number and the positioning of the partition walls and also of the exhaust pipes in the muffler interior 24, an extremely wide range of configurations could be provided.

FIG. 2 illustrates a configuration of such a partition wall by way of example by using the partition wall 26₂. The partition wall 26₂ is formed as a shaped sheet-metal part and has a basically plate-like body 32 oriented substantially orthogonally with respect to the muffler longitudinal axis SL. In the outer circumferential region, the body 32 is adjoined by an edge region 34 formed by swaging, with which the partition wall 26₂ rests on the inner surface of the circumferential wall 14. For example, in association with the partition wall 26₂, the circumferential wall 14 can have an indentation running around in the circumferential direction, in which the edge region 34 is received for the defined retention of the partition wall 26₂.

In order to permit communication contributing to the silencing action between the two chambers 28₂, 28₃ separated from one another by the partition wall 26₂, a plurality of connecting openings 36 can be provided in the body 32 of the partition wall 26₂. Furthermore, a pipe opening 38, 40 is in each case provided in association with the exhaust pipes 30 leading through the partition wall 26₂. The pipe openings 38, 40 can be formed as passages, so that an opening edge portion of the partition wall 26₂ is formed in the region of each of the pipe openings 38, 40, respectively delimiting these pipe openings 38, 40, curved over in the axial direction and extending in the axial direction. An exhaust pipe 30 passing through a corresponding pipe opening 38, 40 can be fastened to such an opening edge portion, for example by welding.

While the basic structure of such a muffler has been described previously, a modification according to the disclosure of the partition wall 26₂ previously described in detail with reference to FIG. 2 is explained below with reference to FIGS. 3 and 4. It should also be emphasized in this connection that the aspects of the configuration described below in connection with the pipe opening 38 of the partition wall 26₂ can equally be implemented in all or some of the other partition walls 26₁, 26₃, 26₄, 26₅ or in all or in only some of the pipe openings provided in the partition walls 26₁, 26₂, 26₃, 26₄, 26₅.

In connection with the pipe opening 38, FIG. 3 illustrates that, differing from those that can be seen in FIG. 2, these are substantially circular and have a configuration like an extended hole matched to the external circumferential contour of the cross-sectional geometry of the exhaust pipe 30 passing through the same. The pipe opening 38 having this configuration forms a compensation pipe opening 42 which has a compensation opening internal dimension I_L in a compensation opening longitudinal direction R_A, which is greater than an opening transverse dimension I_Q of the compensation pipe opening 42 transverse to the compensation opening longitudinal direction R_A. Both the compensation opening longitudinal dimension I_L and the opening transverse dimension I_Q of the compensation pipe opening 42 are viewed orthogonally relative to an opening central axis M_O that can be seen in FIG. 4.

The compensation pipe opening 42 or the partition wall 26₂ providing a compensation partition wall 44 in this configuration is shaped in such a way that opening edge portions 48, 50 are formed on the passage 46 surrounding the compensation pipe opening 42, extend substantially rectilinearly in the compensation opening longitudinal direction R_A and are parallel to each other. The opening edge portions 48, 50 thus form an exhaust pipe receiving portion 53. An exhaust pipe 30, of which the pipe external dimension A_Q orthogonal to the compensation opening longitudinal direction R_A substantially corresponds to the opening transverse dimension I_Q, can be accommodated in the exhaust pipe receiving portion 53. As a result, the exhaust pipe 30 can be accommodated transversely to the compensation opening longitudinal direction R_A substantially without play in the compensation pipe opening 42 but can be arranged at any desired position along the opening edge portions 48, 50 in the compensation opening longitudinal direction R_A. For example, the geometry of the compensation pipe opening 42 can be such that when the exhaust pipe 30 is positioned in an end region of the two opening edge portions 48, 50 in the compensation opening longitudinal direction R_A, the exhaust pipe 30 also rests on a respective curve-like connecting region 52, 54 of the passage 46 also providing the opening edge portions 48, 50. For this purpose, the radius of curvature of these curve-like connecting regions 52, 54 can substantially correspond to the radius of curvature of the outer circumferential surface of the exhaust pipe 30.

FIG. 4 illustrates the region of the muffler 10 in which the exhaust pipe 30 formed as an angled pipe passes through the partition wall 26₂ formed as a compensation partition wall 48. The exhaust pipe 30 has a first pipe portion 56 extending substantially in the direction of a pipe longitudinal axis L_R. The pipe longitudinal axis L_R is positioned substantially parallel, possibly also coaxially, with respect to the opening central axis M_O of the compensation pipe opening 42. At the same time, the pipe longitudinal axis L_R also forms a first pipe longitudinal axis portion L_R1 of the first pipe portion 56.

The exhaust pipe 30 further includes a second pipe portion 58, which is elongated in the direction of a second pipe longitudinal axis portion L_R2. The two pipe longitudinal axis portions L_R1 and L_R2 are substantially orthogonal to each other, so that the exhaust pipe 30 formed as an angled pipe forms a rectangular transition between the two pipe portions 56, 58.

The second pipe portion 58 engages in a pipe opening 62 in the circumferential wall 14, formed, for example, in the region of a passage 60 in the circumferential wall 14. Since the exhaust pipe 30 can be positioned variably in the compensation opening direction R_A in the compensation partition wall 42, there is the possibility of positioning the second pipe portion 58 such that the latter ends flush with the circumferential wall 14 or the passage 60 formed therein and there can be connected to the circumferential wall 14, for example by a weld, or project to a defined extent slightly beyond the passage 60, in order then to be able to implement the welded connection to the circumferential wall 14 in this projecting region. Further re-processing measures for separating an excessively projecting end portion of the second pipe portion 58 are then not necessary.

For a stable structure, the exhaust pipe 30 can then be fixedly connected the first pipe portion 56 to the compensation partition wall 44 either before or after the fixed connection of the second pipe portion 58 to the circumferential wall 14. To this end, for example where the first pipe portion 56 of the exhaust pipe 30 rests on the opening edge portions 48, 50, fastening regions 64, 66 can be formed by a material connection, in particular welding.

In FIGS. 3 and 4 it can clearly be seen that, because of the configuration of the compensation pipe opening 42 in a manner of an elongated hole, on at least one side of the exhaust pipe 30 inserted or passing through the latter in the compensation opening longitudinal direction R_A, in each case an intermediate space 68, 70 is produced, via which the chambers 28₂, 28₃ formed on both sides of the compensation partition wall 44 are connected to each other. This is not critical to the functionality of the muffler 10, since the chambers 28₂ and 28₃ are already connected to each other via the connecting openings 36. If the overall opening cross section provided for this connection is relevant to the silencing characteristic, the opening cross section introduced by the intermediate spaces 68 and/or 70 can be compensated for by a correspondingly smaller number and/or by the dimensioning of the connecting openings 36.

As a result of the configuration according to the disclosure of the muffler 10 with at least one compensation partition wall or compensation pipe opening, it is possible to position a respective exhaust pipe passing through such a compensation pipe opening or engaging in the latter with greater freedom, so that in particular the above-described exact alignment with respect to other components, for example the circumferential wall, is made possible. To this end, it is particularly advantageous if, as illustrated in FIG. 4, the compensation opening longitudinal direction is oriented parallel to that direction in which an exhaust pipe is intended to be aligned exactly with respect to another component. In the configuration illustrated, this is the extension direction of the second pipe longitudinal axis portion L_R2. As can be seen in FIG. 4, this is parallel to the compensation opening longitudinal direction R_A and, in the assembled state, substantially corresponds also to the central axis of the pipe opening 62 formed in the circumferential wall 14.

Configurations according to the disclosure are also particularly advantageous when an exhaust pipe passes through a plurality of partition walls or one or more partition walls and an end wall. As a result, over-dimensioning in the defined positioning is avoided and restraints in those regions in which an exhaust pipe passes through a partition wall or an end wall can be avoided.

It is understood that the foregoing description is that of the preferred embodiments of the invention and that various changes and modifications may be made thereto without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A muffler for an exhaust system of an internal combustion engine, the muffler comprising: a housing having a circumferential wall defining a muffler interior;at least one compensation partition wall arranged in said muffler interior;said at least one compensation partition wall having a compensation pipe opening formed therein;at least one exhaust pipe passing through said at least one compensation partition wall in a region of said compensation pipe opening;said compensation pipe opening defining an opening central axis (MO) and having a compensation opening internal dimension (IL) transverse to said opening central axis (MO) of said compensation pipe opening in at least one compensation opening longitudinal direction (RA) orthogonal to said opening central axis (MO);said exhaust pipe passing through said compensation pipe opening and having a pipe external dimension (AL) in said compensation opening longitudinal direction (RA); and,said compensation opening internal dimension (IL) being greater than said pipe external dimension (AL) in said compensation opening longitudinal direction (RA).

2. The muffler of claim 1, wherein said exhaust pipe has a circular external circumferential contour.

3. The muffler of claim 1, wherein said compensation pipe opening is formed in a manner of an elongated hole; and, said compensation pipe opening is delimited in an exhaust pipe receiving portion by opening edge portions of said compensation partition wall which extend in parallel, rectilinearly to said compensation opening longitudinal direction (RA).

4. The muffler of claim 1, wherein an opening transverse dimension (IQ) of said compensation pipe opening orthogonal to said compensation opening longitudinal direction (RA) corresponds to a pipe external dimension (AQ) of said exhaust pipe, orthogonal to said compensation opening longitudinal direction (RA), at least in a compensation length region of said compensation pipe opening.

5. The muffler of claim 3, wherein a distance of said opening edge portions transverse to said compensation opening longitudinal direction (RA) corresponds to said pipe external dimension (AQ) orthogonal to said compensation opening longitudinal direction (RA).

6. The muffler of claim 1, wherein said exhaust pipe is fixedly connected to said compensation partition wall in at least one fastening region located at a distance from a pipe longitudinal axis (LR) orthogonal to said compensation opening longitudinal direction (RA).

7. The muffler of claim 6, wherein said exhaust pipe is connected to said compensation partition wall in said at least one fastening region by a material connection.

8. The muffler of claim 7, wherein said material connection is a weld.

9. The muffler of claim 3, wherein said exhaust pipe is fixedly connected to said compensation partition wall in at least one fastening region in a region of one of said opening edge portions.

10. The muffler of claim 1, wherein said compensation partition wall is formed as a shaped sheet-metal part; and, said compensation pipe opening is delimited by a passage formed in said compensation partition wall.

11. The muffler of claim 1, wherein said at least one exhaust pipe passing through said compensation pipe opening is formed as an angled pipe having a first pipe portion passing through said compensation pipe opening and elongated in a direction of a first pipe longitudinal axis portion (LR1), and having a second pipe portion engaging in a pipe opening of said circumferential wall and elongated in a direction of a second pipe longitudinal axis portion (LR2); and, said compensation opening longitudinal direction (RA) and said second pipe longitudinal axis portion (LR2) lie in one plane and/or lie parallel to each other.

12. The muffler of claim 11, wherein said first pipe longitudinal axis portion (LR1) and said second pipe longitudinal axis portion (LR2) are orthogonal to each other.

13. The muffler of claim 1, wherein: said muffler defines a muffler longitudinal axis (SL);at least two partition walls following one another in the direction of said muffler longitudinal axis (SL) are provided in said muffler interior;at least one exhaust pipe passes through at least two intermediate walls in a region of respective pipe openings; and,at least one of said partition walls is a compensation partition wall.

14. The muffler of claim 13, wherein each of said at least two partition walls is a compensation partition wall.

15. The muffler of claim 1, wherein at least one connecting opening is formed in at least one compensation partition wall.

16. An exhaust system for an internal combustion engine, comprising at least one muffler including: a housing having a circumferential wall defining a muffler interior;at least one compensation partition wall arranged in said muffler interior;said at least one compensation partition wall having a compensation pipe opening formed therein;at least one exhaust pipe passing through said at least one compensation partition wall in a region of said compensation pipe opening;said compensation pipe opening defining an opening central axis (MO) and having a compensation opening internal dimension (IL) transverse to said opening central axis (MO) of said compensation pipe opening in at least one compensation opening longitudinal direction (RA) orthogonal to said opening central axis (MO);said exhaust pipe passing through said compensation pipe opening and having a pipe external dimension (AL) in said compensation opening longitudinal direction (RA); and,said compensation opening internal dimension (IL) being greater than said pipe external dimension (AL) in said compensation opening longitudinal direction (RA).