Patent Publication Number: US-9890752-B2

Title: Muffler

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is the National Stage of PCT/AT2015/050059filed on Mar. 6, 2015, which claims priority under 35 U.S.C. § 119 of Austrian Application No. 50168/2014 filed on Mar. 7, 2014, the disclosure of which is incorporated by reference. The international application under PCT article 21(2) was not published in English. 
     The invention relates to a muffler, in particular a vehicle muffler, and a vehicle equipped with this muffler. 
     WO 07101412 A1 discloses a muffler based on a modular construction and the manufacture thereof. A plurality of resonator elements is provided for this purpose, which form a labyrinth of passages and resonator chambers. 
     The disadvantage of this construction is the fact that the parts connected to another due to the modular construction have to be assembled in a complicated production process, which makes exact positioning of the individual parts very difficult and places high demands on the positioning accuracy of the machines. 
     DE 10026355 A1 discloses a sound damping air line for an air duct of an internal combustion engine comprising an inner duct with radial holes and a sound damping cladding at least partially covering the inner duct radially on the outside. An outer duct completely surrounds the inner duct and sound damping cladding. Both the outer duct and the inner duct are each made from two half shells, one half shell of the inner duct being hinge-mounted on a half shell of the outer duct and the other half shell of the inner duct being hinge-mounted on the other half shell of the outer duct. The inner duct, outer duct and sound damping cladding are made from plastic. 
     The disadvantage of this construction is that the manufacture of such an air line is enormously complex. In particular, the process of hinge mounting the individual half shells requires several complex operations and in terms of cost, is only economically feasible if using plastic materials. Accordingly, this solution must be ruled out in the case of all applications which require the use of metal, e.g. stainless steel. 
     The objective of this invention is to propose a muffler with a coupling connection, in which the coupling connection is advantageously integrated in the muffler in order to make it easier to connect a component to the muffler. 
     This objective is achieved by the invention on the basis of the features according to the invention. 
     The invention proposes a muffler, in particular a vehicle muffler, comprising at least one resonator chamber. The resonator chamber is bounded by at least a first housing part having a first outer jacket and having a first end wall in which an inflow opening is arranged, disposed on the inflow side, and a first internal pipe segment. The muffler further comprises at least one coupling device for coupling to a turbocharger which is accommodated in the first end wall of the first housing part, which coupling device comprises a coupling body. The coupling body is a shaped sheet metal part, such as a deep-drawn part, and the first housing part is likewise formed integrally from a shaped sheet metal part, such as a deep-drawn part, and the inflow opening of the first housing part has an extension which is tapered in steps in an axial section, in which the coupling body and a sealing element, such as a radial sealing ring, are accommodated. The advantage of using shaped sheet metal parts, especially deep-drawn parts, is that the individual parts can be based on a complex geometry. Deep-drawn parts can be produced economically in terms of resources because deep-drawn parts require very little cutting and thus create little material wastage. Furthermore, repeatability is very good when producing deep-drawn parts, which makes this manufacturing process very suitable for mass production. The deep drawing process also results in a certain degree of strain-hardening of the individual components, which also has a positive effect on the strength of the individual components. 
     An advantage of the design proposed by the invention is that the coupling device, in particular the coupling body, can be very easily connected to a first housing part of the muffler. In this connection, a sealing element can advantageously be accommodated in the muffler, thereby enabling a part to be coupled with the coupling device of the muffler and sealed. The connection between the housing part and coupling body is also easy to produce, so that such a muffler can advantageously be produced in particular in an industrial manufacturing process on a mass production basis. This results in high process reliability and cost-effective production. The muffler is also very easy to assemble and is therefore robust with little susceptibility to faults. 
     It may also be of practical advantage if the coupling body has an outer jacket provided in the form of a fixing portion and the fixing portion is adjoined by an end wall which extends in the direction of the cross-section center and which is provided as an axial stop element. The advantage of this is that such a fixing portion of the coupling body can advantageously be connected to the first housing part. The end wall of the coupling body can then be used as a stop element for positioning the coupling body relative to the first housing part. 
     Furthermore, the end wall of the coupling body may be provided with an over-beading on its inner portion, as viewed radially. The advantage of such an over-heading is that it imparts good stability to the end wall. As a result, the end wall is also able to withstand axial forces without being susceptible to excessive deformation. 
     Furthermore, in the extension tapered in steps, the first end wall of the first housing part is adjoined by a first axial portion which extends in the direction of the resonator chamber and which is provided in the form of a coupling mount, and the coupling body is accommodated in its first internal wall, and the coupling body lies with its outer jacket against the internal wail of the coupling mount. The advantage of this is that the coupling body can be precisely positioned relative to the first housing part and readily accommodated in the first housing part. 
     Also of advantage is a feature whereby the first axial portion of the housing part is adjoined by a first radial portion which extends in the direction of the cross-section and which serves as an axial stop for the coupling body, and the end wall of the coupling body lies against the first radial portion. The advantage of this is that the coupling body can be positioned relative to the first housing part in the axial direction. 
     Based on another embodiment, the first radial portion is adjoined by a second axial portion which extends in the direction of the resonator chamber and which serves as a seal mount, and the sealing element is accommodated on its second internal wall, and the second axial portion has a smaller cross-sectional dimension than the first axial portion. The advantage of this is that the sealing element can be accommodated in this cross-section, thereby enabling a seal to be provided for another component. 
     It may also be of practical advantage if the second axial portion of the housing part is adjoined by a second radial portion which extends in the direction of the cross-section center and which serves as an axial stop for the sealing element. The advantage of this is that the sealing element is also accommodated in the axial direction, secured in the first housing part. 
     Furthermore, the second radial portion is adjoined by a third axial portion which extends in the direction of the resonator chamber and which is provided in the form of an internal pipe segment, and the third axial portion has a smaller cross-sectional dimension than the second axial portion. The advantage of this is that an internal pipe segment for creating a resonator chamber is formed by the first housing part. This obviates the need for additional components to make an internal pipe segment and avoids a complex construction of the muffler involving several individual parts. 
     Furthermore, the axial distance between a first stop surface of the first radial portion and a second stop surface of the second radial portion is slightly bigger than an axial extension of the sealing element The advantage of this is that the sealing element can be accommodated, axially secured in the muffler, and the sealing element is nevertheless not subjected to axial load in the assembled state and the sealing effect is not detrimentally affected. 
     It is also of practical advantage that the end wall of the coupling body extends farther in the direction of the cross-section center than the internal wail of the second axial portion, as a result of which the end wall forms a part-region extending beyond the second axial portion, and as a result of which the sealing element is accommodated in the extension tapered in steps, secured to prevent axial movement. The advantage of this is that the sealing element can be accommodated in the muffler, axially secured, without having to use additional components. This minimizes the complexity of producing such a muffler and thus increases process reliability during the manufacturing operation. 
     Based on another advantageous embodiment, the fixing portion of the coupling body is connected to the first axial portion and/or to the end wall of the first housing part by a cohesively bonded connection, such as a welded connection, in particular a laser welded connection. The advantage of this is that such a cohesively bonded connection is easy to produce and is also suitable for providing an adequate connection of the individual components. Another advantage of a laser welded connection is that the heat introduced into the welded connection is locally limited and the surfaces on which the sealing element lies do not become too hot, thereby protecting the sealing element. 
     Alternatively, the end wall of the coupling element may be connected to the first radial portion of the first housing part by a cohesively bonded connection, such as a welded connection, in particular a laser welded connection. The advantage of this is that such a cohesively bonded connection is easy to produce and is also suitable for providing an adequate connection of the individual components. Another advantage of a laser welded connection is that the heat introduced into the welded connection is locally limited and the surfaces on which the sealing element lies do not become too hot, thereby protecting the sealing element. 
     Based on another alternative variant, the fixing portion of the coupling body is connected to the first axial portion of the first housing part by a positive connection, such as a press-fit connection. The advantage of this is that such a press-fit connection is easy to produce. Accordingly, this connection is particularly suitable for mass production. A positive connection also obviates the need for a welded connection, thereby avoiding the introduction of heat into the muffler  1  and hence thermal distortion. 
     The advantage of the design proposed by the invention is that the muffler is made up of as few individual parts to be assembled with one another as possible. This keeps production complexity to a minimum because as few welded connections as possible are needed. The reliability of the muffler can therefore be increased and production costs for such a muffler can also be kept to a minimum. Another advantage of such a muffler proposed by the invention is that thermal stress to the individual components during the manufacturing process can be kept as low as possible. Accordingly, internal stress in the individual parts of the muffler and distortion caused by internal stress can be minimized as far as possible and/or avoided. 
    
    
     
       To provide a clearer understanding, the invention will be described in more detail below with reference to the appended drawings. 
       These are highly simplified, schematic diagrams illustrating the following: 
         FIG. 1  a perspective view of a muffler; 
         FIG. 2  a diagram in section showing a muffler in section along its center line; 
         FIG. 3  a diagram in section of another example of an embodiment of a muffler in section along its center line; 
         FIG. 4  a diagram in section of a muffler with a detail showing the coupling connection, based on a cohesive material connection; 
         FIG. 5  an exploded view of a muffler; 
         FIG. 6  a vehicle with a muffler connected to the turbocharger; 
         FIG. 7  a diagram in section of a muffler with a detail showing the coupling connection, based on a press-fit connection. 
     
    
    
     Firstly, it should be pointed out that the same parts described in the different embodiments are denoted by the same reference numbers and the same component names and the disclosures made throughout the description can be transposed in terms of meaning to same parts bearing the same reference numbers or same component names. Furthermore, the positions chosen for the purposes of the description, such as top, bottom, side, etc., relate to the drawing specifically being described and can be transposed in terms of meaning to a new position when another position is being described. 
       FIGS. 1 and 2  illustrate a first embodiment of a muffler  1 , in particular a vehicle muffler. 
       FIG. 1  is a perspective view of the muffler  1 . The muffler  1  in this view comprises a first housing part  2  and a second housing part  3 , which are connected to one another in a connection region  4 . However, it would also be possible to provide a one-piece housing which forms the interior of the muffler. The muffler  1  is provided in the form of a rotationally symmetrical hollow body and thus has a central axis  5 . The embodiment of the invention described in more detail below is not restricted to a rotationally symmetrical hollow body and it would also be conceivable for the muffler  1  to have an approximately rectangular or polygonal cross-section. 
     A coupling-device  6  is connected to the first housing part  2 , the purpose of which is to enable the muffler  1  to be coupled with a turbocharger  9 . In particular, the coupling device  6  is used as a means of enabling the muffler  1  to be removed from the turbocharger  9  and fitted back on the turbocharger  9  as quickly and easily as possible if necessary in the event of damage to the turbocharger  9  or in the event that an engine repair is necessary. The coupling device  6  comprises a coupling body  7  which is designed to be connected to and/or pushed onto a connector fitting of the turbocharger  9 . 
       FIG. 2  shows a section through a muffler  1  along its central axis  5 . In this diagram in section, the coupling device  6  and its coupling body  7  are clearly visible. A fixing element  8  may also be provided on the coupling device  6 , by means of which the muffler  1  can be affixed to the turbocharger  9 . As illustrated here, this fixing element  8  may be a wire bracket. This fixing element  8  may co-operate with a corresponding recess  10  in the turbocharger  9 , respectively a recess  10  in a connector fitting  11  of the turbocharger  9 . 
     In  FIG. 2 , the muffler  1  is illustrated in the fitted state and the connector fitting  11  of the turbocharger  9  is inserted in the muffler  1 , respectively in the coupling device  6 . 
     The illustrated muffler  1  further comprises a first resonator chamber  12  and a second resonator chamber  13 . As viewed in a flow direction  14 , the first resonator chamber  12  is disposed upstream of the second resonator chamber  13 . Instead of two resonator chambers  12 ,  13 , it would be possible to provide only one resonator chamber  12  or equally more resonator chambers. In terms of the design of the muffler  1  proposed by the invention, it is irrelevant how many resonator chambers it comprises and it is solely the design of the first, possibly also single, resonator chamber  12 , respectively the first housing part  2  that matters. 
     Accordingly, the first resonator chamber  6  is bounded by a first outer jacket  15  and a first end wall  16 . The first outer jacket  15  and the first end wall  16  are incorporated in the first housing part  2 . To be more precise, the first resonator chamber  12  in the outer region thereof is bounded by a jacket internal face  17  of the first outer jacket  9  and by an internal end face  18  of the first end wall  16 . 
     The first end wall  16  has an inflow opening  19  through which the medium, in particular the compressed intake air, is able to flow into the first resonator chamber  12 . 
     The first resonator chamber  12  is also bounded by a first internal pipe segment  14  respectively by an outer jacket surface  15  of the first internal pipe segment  20  and by a chamber partition wall  21 , respectively a first wall surface  22  of the chamber partition wall  21 . In the case of an embodiment in which the muffler  1  has only one resonator chamber  12 , the first resonator chamber  12  is directly adjoined by the first or second housing part  2 ,  3  instead of the chamber partition wall  21 . 
     The inflow opening  19  also has an extension which is tapered in steps in an axial section  23  for accommodating the coupling device  6 , in particular the coupling body  7 . The tapering step-shaped extension  23  should be fitted in the first resonator chamber  12  so that it bounds the first resonator chamber  12  at the internal face thereof. In particular, an external jacket face  24  of the tapering step-shaped extension  23  bounds the first resonator chamber  12 . 
     The first housing part  2  is therefore disposed on the inflow side  25  of the resonator, respectively the muffler  1 . 
     In the embodiment illustrated in  FIG. 2 , the muffler  1 , which has two resonator chambers, comprises a first housing part  2 , a second housing part  3  and a resonator inner element  26 . The resonator inner element  26  and the first housing part  2  and second housing part  3  are provided in the form of deep-drawn parts based on one advantageous embodiment. In particular, it is of advantage if the first housing part  2  is provided as a deep-drawn part. 
     In the following part of the description, the individual parts which make up the muffler  1  will be described exactly in terms of their design. However, it should be pointed out that the design of these individual parts is based on one advantageous embodiment of the muffler  1 . Not all of the design features of the individual parts described here need necessarily be included in the design proposed by the invention or be as specifically described here. 
     The first housing part  2  comprises a first outer jacket  15 . On the inflow side of the muffler  1 , the first outer jacket  15  is adjoined by the first end wall  16 , adjoining which is the inflow opening  19  and the extension  23  which is tapered in steps in an axial section for accommodating the coupling device  6 . The first end wall  16  therefore adjoins the first outer jacket  15  and extends in the direction towards the center. 
     The muffler  1  further comprises a sealing element  27  which seals the first housing part  2  with respect to the connector fitting  11  of the turbocharger  9 . 
     As may be seen in  FIG. 2 , in the fitted state in which it is pushed onto the connector fitting  11  of the turbocharger  9 , the muffler  1  is secured by the fixing element  8  to prevent axial movement. The sealing element  27  provides the requisite sealing effect between the muffler  1  and connector fitting  11 . The sealing element  27  is preferably provided in the form of a radial seal so that the muffler  1  can be easily fitted on the connector fitting  11  of the turbocharger  9  without any complications. To avoid damage to the sealing element  27  during the process of inserting the connector fitting  11 , the connector fitting  11  may be provided with a chamfer  28  to facilitate fitting of the two parts with one another. 
     When the muffler  1  and turbocharger  9  are in the fitted state as illustrated in  FIG. 2 , a first sealing lip  29  of the sealing element  27  lies against the tapering step-shaped extension  23  of the first housing part  2  and a second sealing lip  30  lies against a sealing surface  31  of the connector fitting  11  of the turbocharger  9 . As may also be seen, the connector fitting  11  is designed such that in the fitted state, a part-region of the external circumference  32  in conjunction with the coupling body  7 , in particular with a jacket internal face  33  of the coupling body  7 , forms a loose fit. This offers a very effective way of fixing the radial position of the muffler  1  relative to the turbocharger  9 . Furthermore, the sealing surface  31  of the connector fitting  11  lies on the tapering step-shaped extension  23  of the first housing part  2  and thus also fixes the position of the muffler  1  relative to the turbocharger  9 . 
       FIG. 3  illustrates another embodiment of the muffler  1  which may be construed as an independent embodiment in its own right, the same reference numbers and component names being used to denote parts that are the same as those described in connection with  FIGS. 1  and  2  above. To avoid unnecessary repetition, reference may be made to the more detailed description of  FIGS. 1 and 2  given above. 
     The embodiment of the muffler  1  illustrated in  FIG. 3  has only a first resonator chamber  12 . In addition to a first housing part  2 , the muffler  1  illustrated here may also comprise a second housing part  3 . However, it would also be possible for the first housing part  2  to be an integral part, in which case a second housing part  3  is not needed. 
       FIG. 3  illustrates the muffler  1  in an assembled state but the muffler  1  is not fitted on the connector fitting  11  of the turbocharger  9 . 
       FIG. 4  illustrates a detail of the interface between the coupling device  6  and first housing part  2 . Since the features of the muffler  1  proposed by the invention are disposed at this transition interface, it is irrelevant whether the muffler has one or more than one resonator chamber. 
     As may be readily seen from the view illustrated in  FIG. 4 , a first axial portion  34  adjoins the first end wall  16  of the first housing part  2  in the extension with tapered steps  23 . The first axial portion  34  extends from the first end wall  16  in the direction of the first resonator chamber  12 , i.e. in the axial direction away from the inflow side  25 . The first axial portion  34  is designed as a coupling mount  35 , and an internal wall  36  of the coupling mount  35  cooperates with and/or is connected to an outer jacket  37  of the coupling body  7 . A fixing portion  38  is disposed in the outer jacket  37  of the coupling body  7  which contacts the internal wall  36  of the coupling mount  35 . 
     Adjoining its outer jacket  37 , the coupling body  7  also has an end wall  39  which is provided as an axial stop element  40 . The end wall  39  extends from the fixing portion  38  in the direction of the cross-section center, and it may be that over-beading  42  is provided, in which case it lies on the inwardly lying portion  41  of the end wall  39  of the coupling body  7  as viewed radially. In this respect, it is preferable if the end wall  39  is over-beaded in the direction of the inflow side  25 , thereby resulting in a smooth stop surface  43  on the end wall  39 . 
     Furthermore, adjoining a first axial portion  34  of the first housing part  2 , a first radial portion  44  is provided, which extends in the direction of the cross-section center. This radial portion  44  may be used as an axial stop for the coupling body. Accordingly, the end wall  39 , in particular a stop surface  43  of the end wall  39  of the coupling body  7 , lies on the first radial portion  44 , in particular on a first stop surface  45  of the first radial portion  44 . 
     Furthermore, adjoining the first radial portion  44  is a second axial portion  46  which extends from the radial portion  44  in the direction of the resonator chamber  12 , i.e. away from the inflow side  25 . The second axial portion  46  is designed as a seal mount and the sealing element  27  is accommodated on the second internal wall  47  thereof. 
     A cross-sectional dimension  48  of the first axial portion  34  is smaller than a cross-sectional dimension  49  of the first outer jacket  15 . A cross-sectional dimension  50  of the second axial portion  46  is likewise smaller than a cross-sectional dimension  48  of the first axial portion  34 . The sealing element  27  is adapted to the diameter of the second axial portion  46 , in particular the second internal wall  47 . 
     Adjoining the second axial portion  46  is a second radial portion  51  which extends in the direction of the cross-section center. This second radial portion  51  may be used as an axial stop for the sealing element  27 . In particular, the second radial portion  51  forms a second stop surface  52 , against which the sealing element  27  can be pressed. 
     The first radial portion  44  and the second radial portion  51  are positioned relative to one another in such a way that an axial distance  53  between the first stop surface  45  and between the second stop surface  52  is bigger than an axial extension  54  of the sealing element  27 . This being the case, the sealing element  27  can be readily accommodated in the second axial portion  46 . 
     Furthermore, the end wall  39  of the coupling body  7  may extend farther in the direction of the cross-section center than the internal wall  47  of the second axial portion  46 . Accordingly, the end wall  39  forms a part-region  55  which extends beyond the second axial portion  46 . In other words, the end wall  39  of the coupling body  7  extends farther in the direction of the cross-section center than the first radial portion  44  co-operating with the end wall  39 . 
     What this achieves is that the sealing element  27  is axially secured between the end wall  39  of the coupling body  7  and between the second radial portion  51 , positioned in particular between the stop surfaces  43  and  52 . This ensures that when the muffler  1  is fitted on and/or removed from the connector fitting  11  of the turbocharger  9 , the sealing element  27  cannot be pushed in the axial direction. 
     Furthermore, the second radial portion  51  may be adjoined by a third axial portion  56  which extends in the direction of the resonator chamber  12 , i.e. at an end remote from the inflow side  25 . An internal wall  57  of the third axial portion  56  may be used as a guide surface for accommodating and contacting the sealing surface  31  of the connector fitting  11 . The cross-sectional dimension  58  of the third axial portion  56  is smaller than a cross-sectional dimension  50  of the second axial portion  46 . 
     The individual axial portions and/or radial portions of the tapering step-shaped extension  23  described above may be simultaneously provided in the form of an internal pipe segment  20 . 
     The coupling body  7  is preferably connected to the first housing part  2  by a cohesively bonded connection, such as a welded connection. In terms of the method of producing the welded connection, laser welding and/or plasma welding is preferably used. There are several different options in terms of positioning a weld seam by means of which the coupling body  7  can be connected to the first housing part  2 . 
     For example, one option is to provide a first fillet weld  59  applied in the radius between the first end wall  16  and first axial portion  34  of the first housing part and outer jacket  37  of the coupling body  7 . 
     Another option is to provide the weld seam in the form of a surface connection  60  between the fixing portion  38  of the coupling body  7  and the internal wall  36  of the coupling mount  35 . This being the case, the outer jacket  37  of the coupling body  7  may be provided with slit-like recesses  61  for applying the welding energy. 
     Another option for a welded connection is to use a second surface connection  62  between the first stop surface  45  of the first radial portion  44  and the stop surface  43  of the end wall  39  of the coupling body  7 . Here too, the end wall  39  of the coupling body  7  may have slit-like recesses, not illustrated, by means of which the welding energy can be introduced into the intermediate surface. 
     Another option is to provide a second fillet weld  63  positioned between a transition radius of the first radial portion  44  and the second axial portion  46  and the end wall  39  of the coupling body  7 . 
     Another possibility, for example, is to provide another outer jacket  46  of the coupling body  7  which is designed and shaped so that it abuts with the first end wall  16  of the first housing part  2  and can be joined thereto by a welded connection. 
       FIG. 5  is an exploded diagram illustrating the muffler  1 . This clearly illustrates how the muffler  1  is produced and assembled. 
     At the start of the production process, at least the first housing part  2  and the coupling body  7  are deep drawn to obtain their characteristic shape. 
     In another method step, the first housing part  2  is held by a device or a manipulator robot. The sealing element  27  can then be axially inserted in the housing part  2 , in particular in the tapering step-shaped extension  23 . 
     Once the sealing element  27  has been positioned relative to the first housing part  2 , the coupling body  7  can be pushed into the tapering step-shaped extension  23  in another method step. At this stage, the coupling body  7  should be oriented so that the end wall  39  of the coupling body  7  is directed towards the first housing part  2 . The coupling body  7  can be pushed into the first housing part  2  until the stop surface  43  of the end wall  39  lies against the first stop surface  45  of the first radial portion  44 . The coupling body  7  does not therefore have to be axially positioned relative to the first housing part  2  but merely inserted therein as far as the stop. 
     During another method step, the coupling body  7  and first housing part  2  are connected to one another by a welded connection, in particular a laser or plasma welded connection. The advantage of a laser or plasma welded connection is that only very little heat has to be applied and is locally limited. As a result, the sealing element  27  is not damaged during the welding operation. 
       FIG. 6  illustrates a vehicle  65  with the turbocharger  9  and a muffler  1  as proposed by the invention connected to the pressure side of the turbocharger  9 . 
       FIG. 7  illustrates another embodiment of the muffler  1  which may optionally be construed as an independent embodiment in its own right, the same reference numbers and component names being used to denote parts that are the same as those described in connection with  FIGS. 1, 2 and 4  above. To avoid unnecessary repetition, reference may be made to the detailed descriptions of  FIGS. 1, 2 and 4  given above. 
     As may be seen from  FIG. 7 , it is also conceivable for the coupling body  7  and first housing part  2  to be connected to one another by a positive connection rather than being welded to one another. This positive connection may be achieved in the form of a press-fit connection  66 . Such a press-fit connection  66  can be produced particularly effectively between the first axial portion  34  and fixing portion  38  of the coupling body  7 . To this end, these wall portions are shaped together to create the positive connection. This positive connection can be produced by means of a tool which is positioned inside the coupling body  7  and pushes the fixing portion  38  of the coupling body  7  outwards. The positive connection can be then be obtained by a circumferentially extending press-fit connection  66 . However, another option would be a press-fit connection  66  in only circumferentially extending segments. 
     The embodiments illustrated as examples represent possible variants of the muffler  1 , and it should be pointed out at this stage that the invention is not specifically limited to the variants specifically illustrated, and instead the individual variants may be used in different combinations with one another and these possible variations lie within the reach of the person skilled in this technical field given the disclosed technical teaching. 
     Furthermore, individual features or combinations of features from the different embodiments illustrated and described may be construed as independent inventive solutions or solutions proposed by the invention in their own right. 
     The objective underlying the independent inventive solutions may be found in the description. 
     All the figures relating to ranges of values in the description should be construed as meaning that they include any and all part-ranges, in which case, for example, the range of 1 to 10 should be understood as including all part-ranges starting from the lower limit of 1 to the upper limit of 10, i.e. all part-ranges starting with a lower limit of 1 or more and ending with an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1 or 5.5 to 10. 
     Above all, the individual embodiments of the subject matter illustrated in  FIGS. 1 and 2, 3, 4  constitute independent solutions proposed by the invention in their own right. The objectives and associated solutions proposed by the invention may be found in the detailed descriptions of these drawings. 
     For the sake of good order, finally, it should be pointed out that, in order to provide a clearer understanding of the structure of the muffler  1 , it and its constituent parts are illustrated to a certain extent out of scale and/or on an enlarged scale and/or on a reduced scale. 
     
       
         
           
               
             
               
                   
               
               
                 List of reference numbers 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
            
               
                 1 
                 Muffler 
               
               
                 2 
                 First housing part 
               
               
                 3 
                 Second housing part 
               
               
                 4 
                 Connection region 
               
               
                 5 
                 Central axis 
               
               
                 6 
                 Coupling device 
               
               
                 7 
                 Coupling body 
               
               
                 8 
                 Fixing element 
               
               
                 9 
                 Turbocharger 
               
               
                 10 
                 Recess 
               
               
                 11 
                 Connector fitting 
               
               
                 12 
                 First resonator chamber 
               
               
                 13 
                 Second resonator chamber 
               
               
                 14 
                 Flow direction 
               
               
                 15 
                 First outer jacket 
               
               
                 16 
                 First end wall 
               
               
                 17 
                 Jacket internal face 
               
               
                 18 
                 Internal end face 
               
               
                 19 
                 Inflow opening 
               
               
                 20 
                 Internal pipe segment 
               
               
                 21 
                 Chamber partition wall 
               
               
                 22 
                 First wall surface 
               
               
                 23 
                 step-shaped tapering extension 
               
               
                 24 
                 Jacket face 
               
               
                 25 
                 Inflow side 
               
               
                 26 
                 Resonator internal element 
               
               
                 27 
                 Sealing element 
               
               
                 28 
                 Chamfer 
               
               
                 29 
                 First sealing lip 
               
               
                 30 
                 Second sealing lip 
               
               
                 31 
                 Sealing surface 
               
               
                 32 
                 Part-region of external circumference 
               
               
                 33 
                 Jacket internal face of coupling body 
               
               
                 34 
                 First axial portion 
               
               
                 35 
                 Coupling mount 
               
               
                 36 
                 Internal wall of coupling mount 
               
               
                 37 
                 Outer jacket of coupling body 
               
               
                 38 
                 Fixing portion of coupling body 
               
               
                 39 
                 End wall of coupling body 
               
               
                 40 
                 Axial stop element 
               
               
                 41 
                 Radially inner portion 
               
               
                 42 
                 Over-beading 
               
               
                 43 
                 Stop surface 
               
               
                 44 
                 First radial portion 
               
               
                 45 
                 First stop surface 
               
               
                 46 
                 Second axial portion 
               
               
                 47 
                 Second internal wall 
               
               
                 48 
                 Cross-sectional dimension of first axial portion 
               
               
                 49 
                 Cross-sectional dimension of first outer jacket 
               
               
                 50 
                 Cross-sectional dimension of second axial portion 
               
               
                 51 
                 Second radial portion 
               
               
                 52 
                 Second stop surface 
               
               
                 53 
                 Axial distance 
               
               
                 54 
                 Axial extension 
               
               
                 55 
                 Protruding part-region 
               
               
                 56 
                 Third axial portion 
               
               
                 57 
                 Internal wall of third axial portion 
               
               
                 58 
                 Cross-sectional dimension of third axial portion 
               
               
                 59 
                 First fillet weld 
               
               
                 60 
                 First surface connection 
               
               
                 61 
                 Slit-like recess 
               
               
                 62 
                 Second surface connection 
               
               
                 63 
                 Second fillet weld 
               
               
                 64 
                 Other outer jacket of coupling body 
               
               
                 65 
                 Vehicle 
               
               
                 66 
                 Press-fit connection