Silencer

Abstract

A silencer for an exhaust system of an internal combustion engine comprises a silencer housing (12) with a circumferential wall (14) surrounding a silencer interior (24), at least one compensating intermediate wall (44) arranged in the silencer interior (24), and at least one exhaust pipe (30) passing through at least one compensating intermediate wall (44) in the area of ​​a compensating pipe opening (42) formed therein, wherein the compensating pipe opening (42) has an inner compensating opening dimension (IL) transversely to an opening center axis (Mo) of the compensating pipe opening (42) in at least one compensating opening longitudinal direction (RA) orthogonal to the opening center axis (Mo), and the exhaust pipe (30) passing through the compensating pipe opening (42) has a pipe outer dimension (AL) in the compensating opening longitudinal direction (RA), wherein the compensating opening inner dimension (IL) is larger than the pipe outer dimension (AL) in the compensating opening longitudinal direction (RA).

Description

[0001] The present invention relates to a silencer for an exhaust system of an internal combustion engine.

[0002] Such a silencer generally comprises a silencer housing with a circumferential wall extending along the longitudinal axis of the silencer, surrounding the longitudinal axis, and radially outwardly defining the silencer interior. At each axial end of the circumferential wall, there is an end wall axially defining the silencer interior. The circumferential wall can be formed, for example, as a tube formed by winding a sheet metal part, with the end walls, designed as separate sheet metal parts, attached to its two axial ends. In an alternative embodiment, the silencer housing can, for example, be constructed from two housing shells, each forming part of the circumferential wall and part of each end wall.

[0003] To divide the silencer interior into different chambers contributing to sound attenuation, one or more partition walls are provided within the silencer interior, generally supported on the outer perimeter wall. Furthermore, one or more exhaust pipes are provided within the silencer interior, passing through one or more such partition walls in the area of ​​the respective pipe openings. To introduce exhaust gas into or exhaust gas from the silencer interior, at least one exhaust pipe may pass through a pipe opening formed in the perimeter wall and / or at least one exhaust pipe may pass through a pipe opening formed in an end wall.

[0004] From DE 10 2006 016095 A1, a silencer according to the preamble of claim 1 is known. In order to allow a dimensional change induced by thermal expansion of an exhaust pipe which is received by a first pipe section in an elongated compensating pipe opening of a compensating partition wall, the first pipe section is movably received in the compensating pipe opening in the direction of a longitudinal direction of the compensating opening and is acted upon by a tab bent from the compensating partition wall in a contact with a region of an opening edge surrounding the compensating pipe opening which is positioned at the end in the longitudinal direction of the compensating opening.

[0005] DE 10 2015 108495 A1 discloses a silencer in which measures are provided for creating defined deformation zones. These include, among other things, elongated openings formed in an intermediate wall through which exhaust pipes extend.

[0006] From DE 10 2015 102611 A1, a silencer is known in which two exhaust pipes adjoining each other in one exhaust flow direction are positioned interlocking in the area of ​​an opening formed in an intermediate wall of the silencer. One of the pipes has an inner dimension that is larger than the outer dimension of the other pipe, so that a space is formed between them that allows the escape of condensate.

[0007] The object of the present invention is to provide a silencer for an exhaust system of an internal combustion engine, the design of which enables simplified assembly.

[0008] According to the invention, this problem is solved by a silencer for an exhaust system of an internal combustion engine according to claim 1. This silencer comprises a silencer housing with a circumferential wall surrounding a silencer interior, at least one compensating intermediate wall arranged in the silencer interior, and at least one exhaust pipe penetrating at least one compensating intermediate wall in the area of ​​a compensating pipe opening formed therein, wherein the compensating pipe opening has an inner dimension transverse to an opening center axis of the compensating pipe opening in at least one compensating opening longitudinal direction orthogonal to the opening center axis, and the exhaust pipe penetrating the compensating pipe opening has an outer dimension in the compensating opening longitudinal direction, wherein the inner dimension of the compensating opening is larger than the outer dimension of the pipe in the compensating opening longitudinal direction.

[0009] By providing such a compensating pipe opening to accommodate an exhaust pipe, it is possible to position the exhaust pipe passing through this opening in various ways relative to the compensating partition along the longitudinal direction of the opening. This avoids over-prescription in the positioning of such an exhaust pipe when it also passes through other components of the silencer, such as other partitions and / or an end wall or the circumferential wall. Conversely, the permissible variation in the positioning of an exhaust pipe in relation to a compensating partition during assembly allows for precise positioning relative to another component it passes through, such as the circumferential wall or an end wall.This precise positioning achievable during the assembly of these components can, in turn, help to avoid further processing measures, such as cutting off a protruding pipe section.

[0010] For a design that is easy to implement, the exhaust pipe can have an essentially circular outer circumference.

[0011] To facilitate the variable positioning of an exhaust pipe within a compensating pipe opening, the compensating pipe opening is designed as an elongated hole. Within an exhaust pipe receiving section, the compensating pipe opening is bounded by opening edge sections of the compensating partition that are essentially parallel to the longitudinal direction of the compensating pipe opening and extend in a substantially straight line. Within the extension area of ​​the exhaust pipe receiving section, the exhaust pipe can then be positioned essentially freely without creating constraints between the two opening edge sections.

[0012] In order to achieve a stable structure, a transverse opening dimension of the compensating pipe opening can, at least in a compensating length region of the compensating pipe opening, correspond essentially orthogonally to a pipe outer dimension of the exhaust pipe orthogonally to the compensating opening longitudinal direction.

[0013] For example, it may be provided that the distance between the opening edge sections, essentially transverse to the compensating opening longitudinal direction, corresponds essentially to the pipe outer dimension orthogonal to the compensating opening longitudinal direction.

[0014] A stable structure can be further supported by firmly connecting the exhaust pipe to the compensating partition wall in at least one fastening area that is orthogonal to the longitudinal direction of the compensating opening and at a distance from a longitudinal axis of the pipe.

[0015] For a mechanically stable and thermally resistant design, the exhaust pipe can be connected to the compensating partition wall in at least one fastening area by material bonding, preferably welding.

[0016] Furthermore, for a stable design, it may be provided that the exhaust pipe is firmly connected to the compensating partition wall in at least one fastening area in the area of ​​one of the opening edge sections.

[0017] The compensating partition can be formed as a sheet metal forming part, and the compensating pipe opening can be defined by a passage formed in the compensating partition. This passage can also provide the opening edge sections in the exhaust pipe receiving section of the compensating pipe opening.

[0018] For introducing or releasing exhaust gas into or from the silencer interior, at least one exhaust pipe penetrating a compensating pipe opening is designed as an angled pipe with a first pipe section elongated in the direction of a first pipe longitudinal axis segment and engaging in a pipe opening in the circumferential wall, and a second pipe section elongated in the direction of a second pipe longitudinal axis segment. To achieve, for example, a flush termination of this pipe section with the circumferential wall, particularly in that area where the second pipe section penetrates the circumferential wall or engages in the pipe opening in the circumferential wall, it is further provided that the longitudinal direction of the compensating opening and the second pipe longitudinal axis segment lie in the same plane and / or are substantially parallel to each other.

[0019] If the first pipe longitudinal axis section and the second pipe longitudinal axis section are essentially orthogonal to each other, such an exhaust pipe can be provided as an essentially right-angled angled pipe.

[0020] In order to achieve a defined sound attenuation characteristic, it is proposed that at least two partition walls arranged successively in the direction of a longitudinal axis of the silencer are provided in the silencer interior, that at least one exhaust pipe passes through at least two partition walls in the area of ​​a respective pipe opening, and that at least one, preferably each of the partition walls is a compensating partition wall.

[0021] For communication between the chambers separated by a compensating partition, which also contributes to sound attenuation, at least one, preferably a plurality of connecting openings can be formed in at least one, preferably each, compensating partition.

[0022] The invention further relates to an exhaust system for an internal combustion engine, comprising at least one silencer constructed according to the invention.

[0023] The present invention is described in detail below with reference to the accompanying figures. These show: Fig. 1 a perspective view of a silencer shown with a partially open housing; Fig. 2 an intermediate wall of the silencer Fig. 1 Fig. 3 a detailed view of the partition wall of the Fig. 2 , if this is designed as a compensating partition; Fig. 4 a basic partial longitudinal section view of the silencer of the Fig. 1 with a partition wall designed as a compensating partition wall.

[0024] In Fig. 1 A silencer for the exhaust system of an internal combustion engine is generally designated by 10. The silencer 10 comprises a silencer housing 12 with a [missing information] formed, for example, by winding a sheet metal element and in Fig. 1 The circumferential wall 14, shown only partially, and at both axial end regions 16, 18 of the circumferential wall 14, spaced apart in the direction of a silencer longitudinal axis SL, each end wall 20, 22. The circumferential wall 14 and the end walls 20, 22 define a silencer interior 24 through which exhaust gas flows.

[0025] In the illustrated embodiment, five partition walls 261, 262, 263, 264, 265 are arranged in the silencer interior 24. The partition walls 261, 262, 263, 264, 265 are supported on the inside of the perimeter wall 14 in a respective outer circumferential region and, between themselves and also in conjunction with the end walls 20, 22, form respective chambers 281, 282, 283, 284, 285, 286 of the silencer 10.

[0026] Inside the silencer 10 extend several exhaust pipes, generally designated 30 and only partially shown. The exhaust pipes 30 serve to introduce the exhaust gas emitted by an internal combustion engine into the silencer 10, or rather into its interior 24, to guide it through the various chambers 281, 282, 283, 284, 285, 286, and to discharge it from the silencer 10. For example, exhaust pipes 30 can penetrate the circumferential wall 14 and / or exhaust pipes 30 can penetrate one or more intermediate walls 261, 262, 263, 264, 265, as well as one or both end walls 20, 22.

[0027] It should be noted in this context that in Fig. 1 The silencer 10 is shown only as an example. Naturally, a wide variety of configurations could be provided with regard to the number and positioning of the partitions as well as the exhaust pipes inside the silencer 24.

[0028] The Fig. 2 An example of such a partition wall is illustrated using the partition wall 26 2. The partition wall 26 2 is designed as a sheet metal forming part and has a body 32 that is essentially plate-like and oriented substantially orthogonally to the longitudinal axis SL of the silencer. A flanged edge region 34 adjoins the body 32 on its outer circumference, and this flange rests against the inner surface of the circumferential wall 14. For example, the circumferential wall 14 can have a circumferential recess corresponding to the partition wall 26 2, in which the flange region 34 is received to provide defined support for the partition wall 26 2.

[0029] To enable communication between the two chambers 28 2, 28 3 separated by the partition wall 26 2, thus contributing to sound attenuation, a plurality of connecting openings 36 can be provided in the body 32 of the partition wall 26 2. Furthermore, a pipe opening 38, 40 is provided in association with each exhaust pipe 30 passing through the partition wall 26 2. The pipe openings 38, 40 can be designed as through-passes, such that an opening edge section of the partition wall 26 2 is formed in the area of ​​each pipe opening 38, 40, which is either curved in the axial direction or extends in the axial direction. An exhaust pipe 30 passing through a respective pipe opening 38, 40 can be fixed to such an opening edge section, for example, by welding.

[0030] While the basic structure of such a silencer was described above, the following section refers to the... Fig. 3 und 4 an inventive modification of the foregoing with reference to the Fig. 2 The detailed description of the partition wall 26 2 is explained. It should also be emphasized in this context that the design aspects described below in connection with the pipe opening 38 of the partition wall 26 2 can be implemented equally in all or some of the other partition walls 26 1 , 26 3 , 26 4 , 26 5 or in all or only some of the pipe openings provided in the partition walls 26 1 , 26 2 , 26 3 , 26 4 , 26 5.

[0031] In Fig. 3 In connection with the pipe opening 38, it is shown that this, deviating from the one in Fig. 2 The recognizable, essentially circular cross-sectional geometry, adapted to the outer circumference contour of the exhaust pipe 30 penetrating it, has an elongated hole-like design. With this configuration, the pipe opening 38 forms a compensating pipe opening 42, which has an inner compensating opening dimension IL in a compensating opening longitudinal direction RA that is larger than a transverse opening dimension IQ of the compensating pipe opening 42 perpendicular to the compensating opening longitudinal direction RA. Both the compensating opening longitudinal dimension IL and the opening transverse dimension IQ of the compensating pipe opening 42 are orthogonal to a Fig. 4 The recognizable opening center axis Mo is considered.

[0032] The compensating pipe opening 42, or the intermediate wall 26 2 which in this embodiment provides a compensating partition 44, is shaped such that opening edge sections 48, 50 are formed on the passage 46 surrounding the compensating pipe opening 42. These opening edge sections extend substantially straight in the longitudinal direction RA of the compensating opening and are parallel to each other. The opening edge sections 48, 50 thus form an exhaust pipe receiving section 53. An exhaust pipe 30 can be received in the exhaust pipe receiving section 53, the outer pipe dimension AQ of which corresponds substantially to the transverse opening dimension IQ, orthogonal to the longitudinal direction RA of the compensating opening. This allows the exhaust pipe 30 to be received in the compensating pipe opening 42 transversely to the compensating opening longitudinal direction RA essentially without play, but it can be arranged in any position in the compensating opening longitudinal direction RA along the opening edge sections 48, 50.For example, the geometry of the compensating pipe opening 42 can be such that when the exhaust pipe 30 is positioned in the longitudinal direction RA of the compensating opening at one end of the two opening edge sections 48, 50, the exhaust pipe 30 also rests against a respective arc-shaped connecting area 52, 54 of the passage 46, which also provides the opening edge sections 48, 50. For this purpose, the radius of curvature of these arc-shaped connecting areas 52, 54 can essentially correspond to the radius of curvature of the outer circumferential surface of the exhaust pipe 30.

[0033] The Fig. 4 Figure 1 illustrates the area of ​​the silencer 10 in which the exhaust pipe 30, designed as an angled pipe, passes through the partition wall 26 2, designed as a compensating partition 48. The exhaust pipe 30 has a first pipe section 56 extending essentially in the direction of a longitudinal pipe axis LR. The longitudinal pipe axis LR is positioned essentially parallel, or possibly coaxial, to the center axis Mo of the compensating pipe opening 42. Simultaneously, the longitudinal pipe axis LR also forms a first longitudinal pipe section L R1 of the first pipe section 56.

[0034] The exhaust pipe 30 further comprises a second pipe section 58, which is elongated in the direction of a second pipe longitudinal axis section L R2. The two pipe longitudinal axis sections L R1 and L R2 are essentially orthogonal to each other, so that the exhaust pipe 30, designed as an angled pipe, forms a right-angled transition between the two pipe sections 56, 58.

[0035] The second pipe section 58 engages in a pipe opening 62 formed, for example, in the area of ​​a passage 60 in the circumferential wall 14. Since the exhaust pipe 30 can be variably positioned in the compensating opening direction RA in the compensating intermediate wall 42, it is possible to position the second pipe section 58 so that it ends flush with the circumferential wall 14 or the passage 60 formed therein and can be connected to the circumferential wall 14 there, for example, by a weld, or protrudes slightly beyond the passage 60 to a defined extent in order to then realize the weld connection with the circumferential wall 14 in this protruding area. Further post-processing measures to cut off an excessively protruding end section of the second pipe section 58 are then not necessary.

[0036] For a stable construction, the exhaust pipe 30 can then be firmly connected either before or after the second pipe section 58 is firmly connected to the circumferential wall 14, and the first pipe section 56 can be firmly connected to the compensating intermediate wall 44. For this purpose, for example, fastening areas 64, 66 can be formed by material bonding, in particular welding, where the first pipe section 56 of the exhaust pipe 30 abuts the opening edge sections 48, 50.

[0037] In the Fig. 3 und 4 It is clearly evident that, due to the elongated shape of the compensating pipe opening 42, a space 68, 70 is created on each side of the exhaust pipe 30 inserted into or passing through it in the longitudinal direction RA of the compensating opening. The chambers 282, 283 formed on both sides of the compensating partition 44 are connected to each other via these spaces. This does not affect the functionality of the silencer 10, as the chambers 282 and 283 are already connected to each other by means of the connecting openings 36. If the total opening cross-section provided for this connection is relevant to the sound attenuation characteristics, the opening cross-section introduced by the spaces 68 and / or 70 can be compensated for by a correspondingly smaller number and / or dimension of the connecting openings 36.

[0038] The inventive design of the silencer 10 with at least one compensating intermediate wall or compensating pipe opening makes it possible to position each exhaust pipe passing through or engaging in such a compensating pipe opening with greater freedom, thus enabling, in particular, the precise alignment with respect to other components, such as the circumferential wall, as described above. For this purpose, it is particularly advantageous if, as in Fig. 4 As shown, the compensating opening's longitudinal direction is oriented parallel to the direction in which an exhaust pipe is to be precisely aligned with respect to another component. In the illustrated embodiment, this is the direction of extension of the second pipe longitudinal axis section L R2. This is, as shown in Fig. 4to be seen, parallel to the compensating opening longitudinal direction RA and in the assembled state essentially also corresponds to the central axis of the pipe opening 62 formed in the circumferential wall 14.

[0039] The design according to the invention is also particularly advantageous when an exhaust pipe passes through several partition walls or one or more partition walls and an end wall. This avoids over-constraints in the defined positioning and prevents constraints in those areas where an exhaust pipe passes through a partition wall or an end wall.

Claims

1. A silencer for an exhaust system of an internal combustion engine, comprising: - a silencer housing (12) with a circumferential wall (14) surrounding a silencer interior (24), - at least one compensation partition wall (44) arranged in the silencer interior (24) and separating two chambers (282, 283), - at least one exhaust pipe (30) passing through at least one compensation partition wall (44) in the region of a compensation pipe opening (42) formed therein, formed as an angled pipe having a first pipe portion (56) passing through the compensation pipe opening (42) and elongated in the direction of a first pipe longitudinal axis portion (LR1), and a second pipe portion (58) and elongated in the direction of a second pipe longitudinal axis portion (LR2), wherein the compensation pipe opening (42) has a compensation opening internal dimension (IL) transverse to an opening central axis (MO) of the compensation pipe opening (42) in at least one compensation opening longitudinal direction (RA) orthogonal to the opening central axis (MO), and the exhaust pipe (30) passing through the compensation pipe opening (42) has a pipe external dimension (AL) in the compensation opening longitudinal direction (RA), wherein the compensation opening internal dimension (IL) is greater than the pipe external dimension (AL) in the compensation opening longitudinal direction (RA), wherein the compensation pipe opening (42) is formed in the manner of an elongated hole, wherein the compensation pipe opening (42) is delimited in an exhaust pipe receiving portion (52) by opening edge portions (48, 50) of the compensation partition wall (44) which extend substantially in parallel, substantially rectilinearly to the compensation opening longitudinal direction (RA), characterized in that the second pipe section (58) of the exhaust pipe (30) passing through the compensation partition wall (44) in the region of the compensation pipe opening (42) formed therein engages in a pipe opening (62) of the circumferential wall (14), that the compensation opening longitudinal direction (RA) and the second pipe longitudinal axis portion (LR2) lie in one plane and / or are substantially parallel to each other, and that an interspace (68, 70) connecting the cambers (282, 283) is respectively formed in the compensation pipe opening (42) at each side of the exhaust pipe (30) in the compensation opening longitudinal direction (RA).

2. The silencer as claimed in claim 1, characterized in that the exhaust pipe (30) has a substantially circular external circumferential contour.

3. The silencer as claimed in one of claims 1 or 2, characterized in that an opening transverse dimension (IQ) of the compensation pipe opening (42) substantially orthogonal to the compensation opening longitudinal direction (RA) substantially corresponds to a pipe external dimension (AQ) of the exhaust pipe (30), orthogonal to the compensation opening longitudinal direction (RA), at least in a compensation length region (53) of the compensation pipe opening (42).

4. The silencer as claimed in claim 3, characterized in that a distance of the opening edge portions (48, 50) substantially transverse to the compensation opening longitudinal direction (RA) substantially corresponds to the pipe external dimension (AQ) orthogonal to the compensation opening longitudinal direction (RA).

5. The silencer as claimed in one of claims 1-4, characterized in that the exhaust pipe (30) is fixedly connected to the compensation partition wall (42) in at least one fastening region (64, 66) located at a distance from a pipe longitudinal axis (LR) orthogonal to the compensation opening longitudinal direction (RA).

6. The silencer as claimed in claim 5, characterized in that the exhaust pipe (30) is connected to the compensation partition wall (44) in the at least one fastening region (64, 66) by a material connection, preferably welding.

7. The silencer as claimed in claim 5 or 6, characterized in that the exhaust pipe (30) is fixedly connected to the compensation partition wall (44) in at least one fastening region (64, 66) in the region of one of the opening edge portions (48, 50).

8. The silencer as claimed in one of claims 1-7, characterized in that the compensation partition wall (44) is formed as a shaped sheet-metal part, and in that the compensation pipe opening (42) is delimited by a passage (46) formed in the compensation partition wall (44).

9. The silencer as claimed in one of claims 1-8, characterized in that the first pipe longitudinal axis portion (LR1) and the second pipe longitudinal axis portion (LR2) are substantially orthogonal to each other.

10. The silencer as claimed in one of claims 1-9, characterized in that at least two partition walls (261, 262, 263, 264, 265) following one another in the direction of a silencer longitudinal axis SL are provided in the silencer interior (24), in that at least one exhaust pipe (30) passes through at least two intermediate walls (261, 262, 263, 264, 265) in the region of a respective pipe opening (38, 40), and in that at least one, preferably each, of the partition walls (261, 262, 263, 264, 265) is a compensation partition wall (44).

11. The silencer as claimed in one of claims 1-10, characterized in that at least one, preferably a plurality of connecting openings (36) is formed in at least one, preferably each, compensation partition wall (44).

12. An exhaust system for an internal combustion engine, comprising at least one silencer (10) as claimed in one of claims 1-11.

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