A muffler including one or more sensor ports

Abstract

The present invention relates to a sealing assembly for a sensor port of a double-walled muffler, and to a muffler provided with such a sealing assembly. The assembly comprises at least an outer plate and a gasket-type element. The gasket-type element has a planar portion provided with an opening, and a pipe portion extending from the edge of the opening. The assembly is mounted on the sensor port, which is provided with a boss fixed to the inner wall of the double muffler wall, and an opening surrounding the boss is provided in the outer wall. The pipe portion is assembled on the boss and the assembly is fixed to the outer wall of the muffler. Due to the lateral movement freedom of the gasket-type element relative to one or more plates, and due to the fact that the boss can move relative to the pipe portion in a direction perpendicular to the one or more plates, the boss can perform any radial or lateral movement relative to the outer wall without losing the sealing function.

Description

Technical Field

[0001] The present invention relates to acoustic mufflers, in particular to engine exhaust mufflers, and in particular to the installation of sensors on double-wall mufflers. Such sensors can be used to measure operating parameters of the muffler, such as NOx concentration, NH3 concentration, temperature, pressure, etc. Background Art

[0002] As is known, engine exhaust mufflers are designed in the form of an elongated cylinder with a double-walled shell, which is formed by an inner wall and an outer wall, preferably with thermal insulation material between the inner and outer walls in order to limit the temperature of the outer surface of the muffler and / or increase the internal temperature to optimize the exhaust gas conversion process. When a sensor is mounted on the muffler, it is installed in a sensor port comprising a boss, which is usually welded to the inside of an opening provided in the inner wall. The boss can be provided with an internal thread, into which the sensor housing can be screwed, so that the sensing part of the sensor is inserted into the internal volume of the muffler. On the opposite side, the sensor must be accessible in order to connect it to a measuring unit. To this end, an opening is provided through the outer wall.

[0003] Due to the gaps between the walls, a large temperature difference develops between the inner and outer walls of the muffler once the muffler reaches operating temperature, especially when the gaps are filled with insulating material. Consequently, the inner and outer walls undergo significant dimensional changes relative to each other, both in the axial and radial directions of the muffler. Consequently, the opening in the outer wall needs to be significantly larger than the area required for access to the sensor, so that relative movement of the walls can occur without damaging the sensor or its connection to the measurement unit.

[0004] Especially in large silencers, such as those used in large agricultural machinery such as combines or forage harvesters, the relative movement between the inner wall and the outer wall may be of the order of several millimeters, so that a large gap between the sensor and the outer wall is required, that is, a large opening in the outer wall that surrounds the boss of the sensor port is required.

[0005] The opening allows dust or debris to enter, causing a fire when the dust or dust particles come into contact with the high temperature of the inner wall of the muffler. This problem is particularly serious in working environments containing large amounts of dust or debris particles, such as in agricultural environments. Summary of the Invention

[0006] The present invention relates to a silencer in which the above-mentioned problems have been solved. The present invention relates to a sealing assembly for a sensor port of a double-walled silencer and to a silencer provided with such a sealing assembly. The sealing assembly comprises at least an outer plate and a gasket-type element, which are preferably all made of thin steel sheet material, for example, stainless steel sheet with a thickness of approximately 0.3 mm. According to one embodiment, the assembly further comprises an inner plate. In this case, the plates are assembled one on top of another and have overlapping openings. The gasket-type element has a planar portion provided with an opening and a tube portion extending from the edge of the opening. The planar portion is clamped between the plates or between the single outer plate and the silencer. The assembly is configured so as to allow the gasket-type element to move lateraly relative to the one or more plates. The assembly is mounted on a sensor port, which is provided with a boss fixed to the inner wall of the double muffler wall and an opening surrounding the boss is provided in the outer wall. The pipe section is mounted on the boss, and the single plate or the assembly of plates is fixed to the outer wall of the muffler, thereby sealing the sensor port from the outside of the muffler. Due to the lateral freedom of movement of the gasket-type element relative to the plate or plates, and due to the ability of the boss to move relative to the pipe section in a direction perpendicular to the plate or plates, i.e., in the radial direction of the muffler, the boss can undergo any radial or lateral movement relative to the outer wall without losing the sealing function.

[0007] Thus, the sealing assembly effectively closes the sensor port while still allowing any movement of the boss relative to the outer wall due to temperature differences between the inner and outer walls. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 An image of a prior art muffler suitable for use with agricultural machinery such as a combine harvester.

[0009] Figure 2a for Figure 1 Detail of the sensor port in the muffler shown in. Figure 2b is a cross-sectional view of the sensor port.

[0010] Figure 3a Components of a sealing assembly suitable for use in a muffler according to the present invention are shown.

[0011] Figure 3b An image of the seal assembly in its assembled state.

[0012] Figure 4aFIG. 4 is a cross-sectional view of the sealing assembly and the two sensor ports before the sealing assembly is installed on the two sensor ports.

[0013] Figure 4b A front view of the two sensor ports.

[0014] Figure 5a is a cross-sectional view of the sealing assembly and the sensor port, wherein the sealing assembly is installed on the sensor port.

[0015] Figure 5b A front view of the sensor port with the assembly mounted thereon.

[0016] Figure 6 for Figure 5b Detail of the installed seal assembly shown in , which gives a more detailed view of the positions of the various component parts.

[0017] Figure 7 Details of alternative configurations are provided with regard to the dimensions of the inner and outer panels of the sealing assembly and the dimensions of the openings provided therein.

[0018] Figure 8a and 8b 1 is a diagram illustrating a seal assembly according to the present invention before and after assembly of components, the seal assembly being configured to close a single sensor port.

[0019] Figure 9 An embodiment is shown in which the tube portion of the movable gasket of the sealing assembly is oriented away from the outer wall of the muffler.

[0020] Figure 10 One embodiment is shown in which the sealing assembly includes a single cover plate. DETAILED DESCRIPTION

[0021] The preferred embodiments will now be described with reference to the accompanying drawings.The detailed description does not limit the scope of the invention, which is defined only by the appended claims.

[0022] Figure 1 An example of a large engine exhaust muffler 1, as known in the prior art and currently used in large agricultural machinery such as combine harvesters, is shown. The muffler 1 has a tubular shape with a length of approximately 1.2 m and an outer shell with straight sidewalls 2 and curved upper and lower sections 3. Inside the muffler is an exhaust gas path that can have any known design.

[0023] A pair of sensor ports 4 is provided near the inlet of the muffler 1 , and another pair of sensor ports 4 is provided near the outlet of the muffler 1 . Figure 2a A detailed image of any one of these sensor ports 4 is shown with a sensor 5 mounted therein. Figure 2b A cross-sectional view in a vertical symmetry plane of the port 4 is shown, but without the sensor.

[0024] Include Figure 2a and 2b The images in are intended to illustrate the problems highlighted in the background section, which are related to the fact that the muffler 1 comprises a double outer shell, such as Figure 2b The housing comprises an inner wall 10 and an outer wall 11. Preferably, thermal insulation material (not shown) is present in the space between these walls 10 and 11. The sensor port 4 comprises a boss 12 that is fixed, preferably welded, inside an opening in the inner wall 10 of the housing. The boss 12 comprises a central opening 14, preferably a threaded opening, into which the sensor 5 can be tightly screwed.

[0025] As can be seen in the figures, the outer wall 11 includes openings 13 around the boss 12 and the sensor 5, said openings 13 being much larger than the cross-section of the boss 12 in order to allow the inner wall 10 and the outer wall 11 to move relative to each other due to temperature differences between the two walls without damaging the sensor 5. These openings 13 are present around all of the sensor ports 4 and form a passage location for dust, dirt, or other debris that enters the area between the walls 10 and 11.

[0026] In the silencer 1 according to the invention, such an opening 13 is closed from the environment by a sealing assembly as described below. First, an embodiment of the sealing assembly is described, which is designed to cover a portion similar to Figure 1 However, the present invention is not limited to this particular arrangement and alternative embodiments will be described further in this specification.

[0027] Figure 3a The components of the seal assembly are shown before they are assembled. The assembly comprises an inner cover plate 20, an outer cover plate 21, and two gasket-type elements 22. The term "gasket-type elements" is used in the appended claims to distinguish these elements from "washers" as they are technically understood, i.e., annular elements used, for example, to secure bolts. For the sake of brevity, the term "gasket" will still be used in the detailed description when referring to "gasket-type elements" 22.

[0028] The terms “inner plate” and “outer plate” refer to the position of the cover plate relative to the muffler when the assembly is mounted on the muffler: the inner plate 20 is closer to the muffler than the outer plate 21 .

[0029] Both cover plates 20 and 21 are formed from thin steel, preferably thin stainless steel, which may be as thin as 0.3 mm. Preferably, a thin plate material is used that can be easily adapted to the curvature of the muffler and / or the tilted position of the sensor (which may be necessary for certain types of sensors). However, thicker plate materials are not excluded from the scope of the present invention, and the present invention is not limited to any particular thickness of plate material used for the various components of the sealing assembly.

[0030] In the embodiment shown, the inner plate 20 is smaller than the outer plate 21 and is positioned inside the outer perimeter of the outer plate, but this is not required. The two plates may have the same outer dimensions, or the inner plate 20 may be larger than the outer plate 21, but preferably, only the outer plate 21 is visible when the assembly is mounted on the muffler.

[0031] Each of the plates 20 and 21 is provided with a pair of openings, designated 23 for the inner plate 20 and 24 for the outer plate 21, and positioned relative to one another at a distance corresponding to the distance between the two sensor ports to which the assembly is to be mounted. In the embodiment shown, the openings 23 and 24 in the inner and outer plates have the same shape and size so that they can be aligned with one another when the plates are mounted together, thereby forming a common opening in the assembly of plates 20 and 21.

[0032] Washers 22 each comprise a planar portion 25 provided with a central opening 26 and a tube portion 27 extending from the edge of central opening 26. Washers 22 are also preferably formed from thin stainless steel sheet material, preferably having the same thickness as plates 20 and 21.

[0033] As in Figure 3b As seen in FIG, when these various components are assembled together to obtain the sealing assembly 15, the planar portion 25 of the gasket 22 is inserted between the inner plate 20 and the outer plate 21, with the tube portion 27 extending through the opening 23 of the inner plate 20. Figure 3bAs shown in FIG, the inner plate 20 and the outer plate 21 are attached to each other along the periphery of the inner plate 20 by a plurality of spot welds 30. This may also be a continuous weld or any other suitable attachment method. Preferably, the plates 20 and 21 are attached only along the edge of the smaller of the two plates, or along their common edge when the two plates have the same external dimensions. In any case, the plates 20 and 21 are not attached to each other over their entire overlapping surface. At least in the area surrounding the aligned openings 23 and 24, the plates 20 and 21 are not attached to each other, thereby allowing the gasket 22 to move laterally relative to the plates, that is, in a direction parallel to the plates. This is also achieved by the fact that the cross-section of the outer surface of the tube portion 27 is much smaller than the area of the opening 23 in the inner plate 20 (through which the tube portion 27 extends), that is, there is a considerable gap between the tube portion 27 and the edge of the opening 23.

[0034] As described above, overlapping openings 23 and 24 are identical in size and shape in this embodiment and are aligned with one another so that the common opening formed by the two aligned openings 23 and 24 in the assembly of panels 20 and 21 has the same shape and size as the openings themselves. However, it is also possible to employ openings 24 in outer panel 21 that are larger or smaller than openings 23 in inner panel 20, with the openings positioned one inside the other, or the openings in the outer and inner panels may partially overlap so that the common opening is defined by the intersection between the overlapping openings. However, as described below, the common opening is subject to conditions related to the size of the boss and / or sensor.

[0035] Figure 4a Show Figure 3b The sealing assembly 15 before being installed on a pair of sensor ports 4 is provided with bosses 12 of the same size on each sensor port 4. Figure 4b As best seen in the front view of the embodiment, the outer wall 11 is provided here with a large opening 13 surrounding two adjacent sensor ports 4. The tube portion 27 of the assembly is dimensioned to correspond to the boss 12 so that the tube portion 27 can fit tightly onto the boss 12, as shown in FIG. Figure 5a and 5b The assembly is mounted to the sensor port 4 by placing the pipe portion 27 around the boss 12 until the outer plate 21 contacts the outer wall 11 of the muffler housing. The outer plate 21 is larger than the opening 13 and completely overlaps it. Figure 5b1. The front view of the assembled assembly in FIG. 1 shows the opening 13, the inner plate 20, and the planar portion 25 of the gasket 22 in phantom. In this particular embodiment, the inner plate 20 is smaller than the opening 13 and is positioned inside the opening, but this is not a requirement of the present invention (see below). The outer plate 21 can be attached to the outer wall 11 by roll spot seam welding or any other suitable attachment method.

[0036] Tube portion 27 fits tightly around boss 12, so that the assembly effectively closes the gap between boss 12 and the edge of large opening 13. However, the "tight fit" of tube portion 27 still permits movement of boss 12 relative to tube portion 27 in a direction perpendicular to plates 20 and 21, that is, in the radial direction of the muffler. This permits radial displacement of boss 12 relative to outer wall 11 without stressing the sealing assembly. Furthermore, because tube portion 27 fits tightly around boss 12 and gasket 22 can move relative to plates 20 and 21 in any direction parallel to these plates, lateral displacement of boss 12 relative to outer wall 11 is permitted without compromising the sealing function of the assembly. The gasket 22 follows any lateral movement of the boss 12 relative to the outer wall 11, that is, the gasket 22 moves with the boss 12 by moving relative to the plates 20 and 21, so that the flat portion 25 of the gasket 22 continues to close the gap between the tube portion 27 and the opening 23 in the inner plate 20, and the gap between the boss (and the sensor mounted thereon) and the opening 24 in the outer plate 21. This, of course, requires that the size of the flat portion 25 is large enough so that the gap between the boss 12 and the opening 13 in the outer wall 11 is closed by the flat portion 25 and the plates 20 and 21, regardless of the position of the boss 12 relative to the outer wall 11.

[0037] The sealing function as described above means that the common opening defined by openings 23 and 24 is sufficiently large compared to the cross-section of boss 12 and tubular portion 27, and possibly sufficiently large compared to the cross-section of a sensor mounted on boss 12, so that when the boss is displaced laterally relative to these openings, boss 12 and tubular portion 27, and thus the sensor, remain a distance from the edge of either opening 23 or 24. This holds true regardless of whether openings 23 and 24 are of the same size and shape and completely overlap (as in the embodiment shown), or whether they are of different sizes and / or shapes.

[0038] exist Figure 6 Details of the installed seal assembly are shown in ( Figure 5a As mentioned above, alternative configurations are possible, for example in terms of the dimensions of the inner and outer panels 20, 21 and in terms of the manner in which the assembly is attached to the outer wall 11 of the muffler. Figure 7One alternative configuration is shown, but it will be clear to one skilled in the art that other configurations are possible. Figure 7 In the embodiment of the present invention, the inner plate 20 and the outer plate 21 have the same outer dimensions. The inner plate 20 is now attached to the outer wall 11 of the muffler. It can be seen that, since both plates are formed of thin material, the outer plate 21 is slightly bent towards the inner plate 20 in the area outside the gasket 22. However, this does not hinder the lateral movement of the gasket 22 relative to the plates, which is preferably ensured by welding the plates 20 and 21 together only along their outer edges, for example by a plurality of spot welds 30, as shown in FIG. Figure 7 As shown in . Figure 7 Another difference from the first embodiment, shown in FIG and applicable independently of variations in the relative external dimensions of the panels, is that the opening 23 in the inner panel 20 is larger than the opening 24 in the outer panel 21. The opening 24 thus defines a common opening obtained by overlapping the openings 23 and 24.

[0039] Figure 8a and 8b The sealing assembly according to the present invention is shown, which is suitable for sealing a single sensor port. The various components described above are also present here and Figure 8a and 8b denoted by the same reference numerals. The features and possible alternatives described above also apply to this single-port embodiment. Similarly, by adjusting the sizes and quantities of the various components described above, the assembly according to the present invention can be designed for groups of any number of ports, greater than two. Such an embodiment can include a greater number of cover plates, for example, a single outer cover plate 21 and a separate inner cover plate 20 for each sensor port. If the sensor ports are close enough together, a single gasket 22 can be provided that fits over multiple bosses 12, the gasket comprising a single planar portion 25, multiple openings 26, and multiple tube portions 27 extending from the openings 26.

[0040] Figure 9 An alternative configuration is shown, according to which the sealing assembly is mounted so that the pipe portion 27 is oriented away from the muffler and is fitted to a boss 12 that projects outwardly from the outer wall 11 of the muffler. This is only possible if the boss 12 is effectively implemented in this way, that is, projects sufficiently beyond the outer wall 11. This embodiment shows that the pipe portion 27 can project through the opening 23 in the inner plate 20 (as in the previous embodiment) or through the opening 24 in the outer plate 21 (as in the Figure 9 Except for this difference, all components and features and functions described above also apply to Figure 9 The embodiment shown in .

[0041] According to an alternative embodiment of the invention, the inner cover plate 20 and the outer cover plate 21 are not directly attached to each other. According to one such embodiment, the inner plate 20 is held in place solely by the outer plate 21. In this case, the outer plate 21 must be larger than the inner plate 20 and completely overlap it, and the inner plate 20 must be much larger than the opening 13 in the outer wall 11 of the muffler 1. The outer plate 21 is then fixed to the outer wall 11 of the muffler, for example by rolling spot welds in the peripheral region of the outer plate 21, and thereby holds the inner plate 20 against said outer wall 11. Preferably, the inner plate 20 remains substantially immobile, for example due to the spot welds applied close to the outer periphery of the inner plate 20 and possibly with the aid of high friction between the plates 20 and 21, so as to avoid displacement of the inner plate 20 relative to the outer plate 21 to the extent of losing the sealing function.

[0042] When the inner plate 20 is smaller than the outer plate 21 and is completely positioned within the perimeter of the outer plate 21, while being larger than the opening 13 in the outer muffler wall 11, it is also possible to attach both the inner and outer plates to the muffler wall 11 without attaching them directly to each other. A final embodiment of the sealing assembly cannot be fully assembled before being attached to the muffler, but rather is assembled during the attachment process to the muffler. This process includes attaching the inner plate 20 to the muffler wall 11, for example by spot welding, placing the gasket 22 over the boss 12 of the sensor port, and attaching the outer plate 21 to the muffler wall 11, for example also by spot welding, so that the gasket 22 is mounted between the two plates 20 and 21, thereby achieving the sealing function described above.

[0043] Another alternative embodiment of the sealing assembly does not include two plates, but rather a single cover plate. In this case, the outer plate 21 acts as the single cover plate, having an opening 24 that overlaps the opening 13 in the outer muffler wall 11. Figure 10 This embodiment is shown in . The flat portion 25 of the gasket 22 is now held between a single cover plate 21 and the outer wall 11 of the muffler. The cover plate 21 is attached to the muffler wall in the peripheral area of the plate 21, for example by spot welds indicated by dashed lines 31. This leaves sufficient area between the plate 21 and the muffler wall 11 for the gasket 22 to move relative to the muffler wall 11 and the plate 21 in a direction parallel to the wall 11. The tube portion 27 of the gasket 22 is assembled to the boss 12 in the same manner as described above for the embodiment comprising two cover plates. The single-plate embodiment is also preferably assembled when it is attached to the muffler by the following steps: fitting the gasket 22 onto the boss 12 and placing the flat portion 25 of the gasket against the outer wall 11 of the muffler, followed by placing the single cover plate 21 onto the gasket 22 and attaching the plate 21 to the outer wall 11, for example by spot welds 31.

[0044] The latter embodiment can also be used to seal a group of closely spaced sensor ports 4 by providing a single cover plate 21 and a separate gasket 22 for each sensor port, when each sensor port is provided with its own opening 13 around a boss 12. When one opening 13 surrounds multiple bosses 12, a single cover plate 21 and one or more gaskets 22 can be provided, the gasket 22 including a single planar portion 25 having a plurality of openings 26, with a plurality of tube portions 27 extending from the openings of the single planar portion 25.

[0045] Depending on the embodiment of the seal assembly (single plate or inner / outer plate), the outer cover plate 21 is attached to the outer wall 11 of the muffler. In most embodiments, the outer cover plate 21 is directly attached to the wall. When the outer plate 21 is smaller than the inner plate 20, the outer plate is directly attached to the inner plate 20, which is directly attached to the muffler wall. Therefore, in this case, the outer plate 21 is attached to the muffler wall 11 via the inner plate, which also represents an embodiment of the outer plate being "attached to the outer wall of the muffler."

[0046] Likewise, according to any embodiment, the flat portion 25 of the gasket 22 is mounted between the outer cover plate 21 and the muffler. When the sealing assembly also includes an inner plate, the flat portion 25 is mounted between the plates 20 and 21 and is therefore still "between the outer plate and the muffler".

Claims

1. A muffler (1), comprising an inner wall (10) and an outer wall (11), and comprising at least one sensor port (4), the sensor port comprising a boss (12) adapted to receive a sensor (5), wherein the boss is fixed to the inner wall (10), and wherein the outer wall (11) is provided with an opening (13) surrounding the boss (12), It is characterized by: The muffler further comprises a sealing assembly (15), the sealing assembly (15) comprising: - one or more cover plates (20, 21), said one or more cover plates (20, 21) comprising at least one outer cover plate (21) attached to said outer wall (11) and provided with an opening (24) overlapping with the opening (13) surrounding said boss (12), and at least one gasket-type element (22) comprising a planar portion (25) provided with an opening (26) and a tube portion (27) projecting from the edge of said opening (26), And, where: - the flat portion (25) of the gasket-type element (22) is mounted between the muffler (1) and the outer cover (21) in such a manner as to allow the gasket-type element (22) to move relative to the outer cover (21) in a direction parallel to the outer cover, - the tube portion (27) of the gasket-type element protrudes through the opening (24) of the outer cover (21) or through the opening (13) in the outer wall (11) of the muffler, - the tube portion (27) of the gasket-type element (22) is fitted around the boss (12) in the following manner: o the boss (12) is movable relative to the tube portion (27) in a direction perpendicular to the plane portion (25) of the washer-type element (22), o when the boss (12) moves in a direction parallel to and relative to the outer wall (11), the tube portion (27) and thus the washer-type element (22) as a whole undergo the same movement relative to the outer wall (11) and relative to the outer cover (21), - the planar portion (25) of the washer-type element (22) is dimensioned such that the gap between the boss (12) and the opening (13) in the outer wall (11) is closed by the planar portion (25) and the one or more cover plates (20, 21) regardless of the position of the boss (12) relative to the outer wall (11), The size of the pipe portion (27) of the assembly corresponds to the boss (12) so that the pipe portion (27) can be tightly fitted onto the boss (12).

2. The muffler according to claim 1, characterized in that The sealing assembly comprises only the outer cover plate (21), and wherein the gasket-type element (22) is held against the outer wall (11) of the muffler by the outer cover plate (21).

3. The muffler (1) according to claim 2, comprising two or more sensor ports (4) arranged in groups, each sensor port (4) comprising a boss (12), wherein the outer wall (11) of the muffler is provided with a separate opening (13) for each boss, or at least one opening (13) provided around a plurality of bosses (12), wherein the sealing assembly (15) comprises: - a single outer cover plate (21) provided with a number of openings (23, 24) corresponding to the number of sensor ports (4), - a plurality of gasket-type elements (22), the number of which corresponds to the number of sensor ports (4); or one or more gasket-type elements comprising a single planar portion (25) and a plurality of openings (26) and tube portions (27).

4. The muffler according to claim 1, characterized in that The sealing assembly comprises the outer cover plate (21) and the inner cover plate (20), and wherein: - the outer cover plate (21) and the inner cover plate (20) are assembled one on top of the other and comprise openings (23, 24) that overlap one another, - the outer cover plate (21) and the inner cover plate (20) have a common outer edge, or one cover plate is smaller than the other cover plate and is arranged inside the outer edge of the other cover plate, - the flat portion (25) of the gasket-type element is mounted between the outer cover (21) and the inner cover (20), with the tube portion (27) protruding: o through the opening (23) of the inner cover plate (20) and the opening (13) in the outer wall (11) of the muffler, or o through the opening (24) of the outer cover (21), - the outer cover (21) and the inner cover (20) are arranged relative to each other in such a way as to allow the washer-type element (22) to move relative to the outer cover and the inner cover in a direction parallel to the outer cover and the inner cover, wherein said movement is also enabled by the dimensions of the overlapping openings (23, 24), The sealing assembly (15) is attached to the outer wall (11) of the muffler (1), wherein the outer cover plate (21) faces away from the muffler, wherein depending on the relative sizes of the outer and inner cover plates, one of the following applies: o Only the outer cover plate (21) is directly attached to the outer wall (11) of the muffler, or Writer o only the inner cover plate (20) is directly attached to the outer wall (11) of the muffler and the outer cover plate (21) is directly attached to the inner cover plate (20), or o The inner cover plate (20) and the outer cover plate (21) are both directly attached to the outer wall (11) of the muffler.

5. The muffler (1) according to claim 4, characterized in that The overlapping openings (23, 24) of the outer cover plate (21) and the inner cover plate (20) have the same size and shape and are aligned with each other.

6. The muffler (1) according to claim 4 or 5, characterized in that The inner cover plate (20) and the outer cover plate (21) are attached to each other.

7. The muffler (1) according to claim 6, characterized in that The inner cover panel (20) and the outer cover panel (21) are attached to each other only along their common outer edge or only along the edge of the smaller of the outer and inner cover panels.

8. The muffler (1) according to claim 4, characterized in that The inner cover plate (20) is located inside the periphery of the opening (13) in the outer wall (11) of the muffler (1), and wherein only the outer cover plate (21) is directly attached to the outer wall (11) of the muffler.

9. The muffler (1) according to claim 4, characterized in that The inner cover plate (20) is larger than the opening (13) in the outer wall (11) and completely overlaps with the opening (13) in the outer wall (11).

10. The muffler (1) according to claim 4, comprising two or more sensor ports (4) arranged in groups, each sensor port (4) comprising a boss (12), wherein the outer wall (11) of the muffler is provided with a separate opening (13) for each boss, or at least one opening (13) provided around a plurality of bosses (12), and wherein the sealing assembly (15) comprises: a single inner cover plate (20) and a single outer cover plate (21), each of the inner cover plate (20) and the outer cover plate (21) being provided with a plurality of openings (23, 24) corresponding to the number of the sensor ports (4); or a single outer cover plate (21) and a plurality of inner cover plates (20), - a plurality of gasket-type elements (22), the number of which corresponds to the number of the sensor ports (4); or one or more gasket-type elements (22), the one or more gasket-type elements (22) comprising a single planar portion (25), a plurality of openings (26) and a plurality of tube portions (27).

11. The muffler (1) according to claim 1, characterized in that The one or more cover plates (20, 21) and the gasket-type element (22) are formed from a thin sheet material.

12. The muffler (1) according to claim 11, characterized in that The one or more cover plates (20, 21) and the gasket-type element (22) are formed from a plate material having a thickness of less than 1 mm.

13. A sealing assembly for closing an opening (13) around at least one sensor port (4), the opening being provided in an outer wall (11) of a double wall of a muffler (1), the double wall comprising an inner wall (10) and the outer wall (11), the sensor port (4) comprising a boss (12) fixed to the inner wall (10) and provided inside a surface area of the opening (13), the sealing assembly (15) comprising: - one or more cover plates (20, 21), said one or more cover plates (20, 21) comprising at least one outer cover plate (21) provided with an opening (24) configured to overlap with the opening (13) surrounding said boss (12), and at least one gasket-type element (22) comprising a planar portion (25) provided with an opening (26) and a tube portion (27) projecting from the edge of said opening (26), And among them: - the flat portion (25) of the gasket-type element (22) is configured to be mounted between the muffler (1) and the outer cover (21) in a manner allowing the gasket-type element (22) to move relative to the outer cover (21) in a direction parallel to the outer cover, - the tube portion (27) of the gasket-type element (22) is configured to protrude through the opening (24) of the outer cover (21) or through the opening (13) in the outer wall (11) of the muffler, - The sealing assembly is configured to be attached to the outer wall (11) of the muffler, wherein the outer cover plate (21) faces away from the muffler and the pipe portion (27) is fitted around the boss (12), wherein the size of the pipe portion (27) of the assembly corresponds to the boss (12) so that the pipe portion (27) can be tightly fitted onto the boss (12).

14. The sealing assembly (15) according to claim 13, comprising the outer cover plate (21) and the inner cover plate (20), wherein: - the outer cover plate (21) and the inner cover plate (20) are assembled one on top of the other and comprise openings (23, 24) that overlap one another, - the outer cover plate (21) and the inner cover plate (20) have a common outer edge, or one cover plate is smaller than the other cover plate and is arranged inside the outer edge of the other cover plate, - the planar portion (25) is mounted between the outer cover (21) and the inner cover (20), wherein the tube portion (27) projects through the opening (23) of the inner cover (20) or through the opening (24) of the outer cover (21), - the outer cover (21) and the inner cover (20) are arranged relative to each other so as to allow the washer-type element (22) to move relative to the outer cover and the inner cover in a direction parallel to the outer cover and the inner cover, wherein said movement is also enabled by the dimensions of the overlapping openings (23, 24).

15. The sealing assembly (15) according to claim 13 or 14, characterized in that The inner cover plate (20) and the outer cover plate (21) are attached to each other.

16. The sealing assembly (15) according to claim 13, characterized in that The one or more cover plates (20, 21) and the gasket-type element (22) are formed from a thin sheet material.

17. The sealing assembly (15) according to claim 16, characterized in that The one or more cover plates (20, 21) and the gasket-type element (22) are formed from a plate material having a thickness of less than 1 mm.

Images