Exhaust aftertreatment arrangement, exhaust system and internal combustion engine

Abstract

Exhaust gas aftertreatment arrangement (5) with at least one receptacle (9, 47) for an interchangeable insert element (11, 13), and with an interchangeable insert element (11, 13) which has a bearing / sealing device (21, 23) for supporting and sealing the interchangeable insert element (11, 13) in the receptacle (9, 47) for the interchangeable insert element (11, 13), wherein the bearing / sealing device (21, 23) has at least one bearing element (29) and at least one sealing element (31, 37) separate from the bearing element (29), characterized in that a flexible support element (75) for compensating for thermal linear expansion is arranged in series with the at least one sealing element (37) designed as an axial seal.

Description

[0001] The invention relates to an exhaust aftertreatment arrangement, an exhaust system for an internal combustion engine and an internal combustion engine.

[0002] Particularly during long-term operation of internal combustion engines, a quick and uncomplicated replacement of exhaust aftertreatment elements, such as particulate filter inserts and / or catalytic converter inserts, is necessary. To enable this in a simple and quick manner, removable insert elements are typically provided that can be stored in receptacles of exhaust aftertreatment assemblies, particularly in exhaust aftertreatment modules. These removable insert elements must be stored in an overall structure of the exhaust aftertreatment module, should be as leak-free as possible, and at the same time, should be easy and quick to replace. This results in conflicting objectives. To achieve a high level of tightness, the removable inserts must be seated as tightly as possible in the surrounding housing. However, this contradicts customer-friendly and practical handling during assembly and disassembly.In particular, such interchangeable insert elements typically have a bearing / sealing device designed to support and seal the interchangeable insert element in a receptacle for the interchangeable insert element. The functions of the seal and the bearing are performed by a single component as a functional unit, which component can be designed as a wire mesh ring. In order to support the interchangeable insert element securely and firmly in the receptacle, this component requires a comparatively stiff and generally less compressible design. At the same time, oversizing combined with a certain compressibility is necessary to achieve an adequate sealing effect. This, in turn, results in a very rigid and, in particular, difficult-to-move arrangement of the interchangeable insert element in its receptacle, meaning that considerable forces are required for assembly and disassembly.

[0003] EP 1 298 289 A1 discloses an exhaust gas aftertreatment arrangement with at least one receptacle for a removable insert element and with a removable insert element that has a bearing / sealing device for supporting and sealing the removable insert element in the receptacle for the removable insert element. The bearing / sealing device has an angular circumferential seal that functions as both a bearing element and a sealing element. US 2007 / 0 144 126 A1 discloses an exhaust gas aftertreatment arrangement according to the preamble of claim 1.

[0004] The invention is based on the object of creating an exhaust gas aftertreatment arrangement, an exhaust system for an internal combustion engine and an internal combustion engine, wherein the aforementioned disadvantages do not occur.

[0005] The problem is solved by creating the subject matter of the independent claims. Advantageous embodiments emerge from the subclaims.

[0006] The object is achieved in particular by providing an exhaust gas aftertreatment arrangement with at least one receptacle for an interchangeable insert element and with an interchangeable insert element, which preferably has at least one exhaust gas aftertreatment element, wherein the interchangeable insert element has a bearing / sealing device designed to support and seal the interchangeable insert element in the receptacle provided for the interchangeable insert element. The bearing / sealing device has at least one bearing element and at least one sealing element separate from the bearing element. A flexible support element for compensating for thermal linear expansion is arranged in series with the at least one sealing element designed as an axial seal.By providing the bearing element and the sealing element separately from one another, a functional separation between bearing on the one hand and seal on the other is achieved, thereby eliminating the otherwise existing conflict of objectives. In particular, it is then possible to dimension the bearing element with comparatively high rigidity to close tolerances, in particular to a lower tolerance limit, so that it has good and stable bearing properties and can still be easily inserted into the receptacle. The sealing element, on the other hand, can have high elasticity and compressibility, whereby it can easily be significantly oversized and yet - due to its high elasticity - can be easily inserted into the receptacle. At the same time, the oversizing, together with the high elasticity and compressibility of the sealing element, ensures an improved sealing effect.In particular, both the bearing properties and the sealing properties of the bearing / sealing device can be optimized separately from one another without resulting in disadvantages for the assembly and disassembly behavior of the interchangeable insert element.

[0007] The fact that the bearing element is separate from the sealing element means, in particular, that a functional separation has been established between the bearing and the seal. In particular, the sealing element is spatially separated from the bearing element. These can be differently designed regions of an integral or one-piece element. However, it is preferably provided that the bearing element is different from the sealing element, i.e., that different elements are provided for bearing support on the one hand and for sealing on the other.

[0008] However, according to one embodiment, it is also possible for the bearing element and the sealing element to be designed similarly or identically, wherein the elements in particular can have similar or identical materials or can consist of similar or identical materials.

[0009] The interchangeable insert element is preferably designed to be rotationally symmetrical about a longitudinal axis and can be inserted into a receptacle designed to be rotationally symmetrical about a longitudinal axis—either in the axial or insertion direction. This results in a particularly simple and easy-to-handle design of the interchangeable insert element and the receptacle.

[0010] Here and in the following, an axial direction is a direction that extends in the insertion direction of the interchangeable insert element. A circumferential direction extends concentrically around the axial direction. A radial direction is perpendicular to the axial direction.

[0011] In a preferred embodiment, the at least one sealing element is designed as a radial seal. It is particularly arranged and configured to seal an outer peripheral surface of the interchangeable insert element against an inner peripheral surface of the receptacle.

[0012] Particularly in an embodiment of the interchangeable insert element in which the sealing element is designed as a radial seal, this is preferably arranged directly next to the bearing element in the axial direction, i.e., in the insertion direction. This provides directly adjacent bearing and sealing points in the axial direction, which has a positive overall effect on both the bearing and sealing properties of the interchangeable insert element.

[0013] Alternatively or additionally, it is possible for the at least one sealing element to be designed as an axial seal. It is preferably configured and arranged to seal an axial end surface of the interchangeable insert element against an axial stop surface of the receptacle.

[0014] It is possible for the bearing / sealing device to have at least one sealing element designed as a radial seal and one sealing element designed as an axial seal. This can further increase the tightness of the arrangement of the interchangeable insert element in the receptacle.

[0015] The exhaust gas aftertreatment element, which preferably has the interchangeable insert element, is preferably designed as a particle filter, as an oxidation catalyst, as a catalyst for the selective catalytic reduction of nitrogen oxides (SCR catalyst), or in another suitable manner.

[0016] A preferred embodiment of the interchangeable insert element is characterized in that the bearing element is designed as a wire mesh ring or a wire mesh band. A wire mesh has proven particularly suitable for secure and stable mounting of the interchangeable insert element in the receptacle. A wire mesh ring can be easily pushed axially over the interchangeable insert element; a wire mesh band can also be easily laid, in particular wound, around the interchangeable insert element in a bearing area. The bearing element is preferably dimensioned to match the dimensions of the receptacle with a narrow tolerance, in particular with a narrower tolerance than the sealing element.In particular, the bearing element preferably has an outer diameter that corresponds to an inner diameter of the receptacle at a designated bearing location with a narrow tolerance, in particular with a narrower tolerance than the sealing element, and is preferably only slightly larger than the inner diameter. Thus, the bearing element only needs to be compressed slightly when inserting the interchangeable insert element into the receptacle, and it can ensure a firm and rigid mounting of the interchangeable insert element in the receptacle even with low insertion forces.

[0017] A preferred embodiment of the interchangeable insert element is characterized in that the sealing element is designed as an elastic seal, in particular as an elastic sealing strip or as an elastic sealing ring. It is possible for the sealing element to be made of a temperature-resistant plastic, in particular an elastomer, and in particular to consist of such a plastic. A sealing element is particularly preferred which is designed as a textile seal, in particular comprising or consisting of a textile material. The textile material can comprise or consist of glass fibers, ceramic fibers, aramid fibers, natural fibers, metal fibers or other suitable fibers. It can be designed as a fabric, in particular a unidirectional or multiaxial fabric, as a knitted fabric, warp-knitted fabric, woven fabric, braided fabric, random fiber nonwoven fabric, or in another suitable manner. A multi-layer textile material is also possible.However, other suitable materials for the sealing element are also possible. The sealing element preferably has greater elasticity than the bearing element, and in particular, it has greater compressibility than the bearing element. Furthermore, the sealing element is preferably matched to the receptacle with a higher tolerance than the bearing element. Particularly when designed as a radial seal, it has a larger outer diameter than the bearing element. The outer diameter of the sealing element, in particular compared to the corresponding inner diameter of the receptacle, is larger than the difference in the diameters of the bearing element and the receptacle.This ensures a very efficient sealing effect in the area where the sealing element is mounted on the holder, while the higher compressibility and elasticity of the sealing element also allows for easy insertion or removal of the interchangeable insert element into / from the holder, thus enabling easy assembly and disassembly.

[0018] If the sealing element is designed as a sealing strip, it particularly preferably serves as a radial seal. It is then particularly preferably wrapped around the interchangeable insert element in a sealing area. This results in particular - viewed in the circumferential direction - in a joint where a first end of the sealing strip meets a second end thereof. To prevent a leakage path at this point, the joint is preferably designed as a mat joint or labyrinth joint, with a projection formed at the first end engaging in a recess formed at a second end. In this way, a labyrinth for exhaust gas is created, whereby the leakage path is in any case extended, preferably closed. Such a mat joint or labyrinth joint is preferably designed - viewed in the circumferential direction - according to the tongue and groove principle or in another suitable manner, in particular with two adjacent or at least partially overlapping tracks or fingers.

[0019] If the sealing element is designed as an axial seal, it is preferably designed as an elastic sealing ring. This can then, for example, be easily inserted between the axial end face of the interchangeable insert element on the one hand and the axial stop face of the holder on the other. This creates no joint, thus ensuring a high level of tightness in every case.

[0020] The sealing element is preferably designed as a self-adhesive seal. In particular, it is possible for a double-sided adhesive tape to be arranged on the underside of the sealing element. The design as a self-adhesive seal allows the sealing element to be fixed in place, in particular for the purpose of inserting the interchangeable insert element and thus facilitating assembly. However, a design without self-adhesive properties of the sealing element is also possible, since it is preferably pressed by inserting it into the receptacle, which is tapered in some areas, in particular conically shaped, thereby forming a force-fitting fixation. This is advantageous because the use of adhesive fundamentally carries the risk of evaporation and thus a reduction in the strength of the connection.

[0021] An embodiment of the interchangeable insert element is preferred which is characterized in that it is designed as a primary interchangeable insert element. This means that the interchangeable insert element itself is designed for arrangement in a receptacle of an exhaust gas aftertreatment module, for example, a gas box. Alternatively, an embodiment of the interchangeable insert element is preferred in which it is designed as a secondary interchangeable insert element. This means that the interchangeable insert element is designed for arrangement in a receptacle of a primary insert element. This makes it possible to nest interchangeable insert elements.In this process, a primary interchangeable insert element is inserted into a receptacle of an exhaust gas aftertreatment module, and a secondary interchangeable insert element is inserted into a receptacle of the primary interchangeable insert element before or after the primary interchangeable insert element is inserted into the receptacle of the exhaust gas aftertreatment module. The receptacles of the exhaust gas aftertreatment module, on the one hand, and the primary interchangeable element, on the other hand, can be constructed identically, in particular according to identical design principles. This results in the same advantages in the area of ​​one receptacle as in the area of ​​the other receptacle.

[0022] An exhaust aftertreatment module is preferably designed as an exhaust box with a plurality of receptacles for arranging interchangeable insert elements. The exhaust aftertreatment module is preferably designed in the manner of a shelving system having a plurality of such receptacles.

[0023] It is possible for the primary interchangeable insert element to have an oxidation catalyst as the exhaust aftertreatment element, while the secondary interchangeable insert element has a particulate filter as the exhaust aftertreatment element. Thus, an oxidation catalyst and a particulate filter can ultimately be arranged in series within the primary interchangeable insert element.

[0024] Particularly preferred is an interchangeable insert element designed as a primary interchangeable insert element, which has a receptacle in which a secondary interchangeable insert element is arranged. Preferably, both the primary and the secondary interchangeable insert element each have a bearing / sealing device, each designed according to one of the previously described embodiments.

[0025] An embodiment of the interchangeable insert element is also preferred which has a first housing part with a first exhaust gas aftertreatment element, wherein the first housing part is detachably connected to a second housing part, which has a second exhaust gas aftertreatment element. The two housing parts are particularly preferably screwed together. In particular, the two housing parts together form an insert, i.e. a uniform - in particular primary - interchangeable insert element with a predetermined separation point for separating the housing parts. This preferably eliminates the need for a complex seal and bearing of the second housing part in / on the first housing part, which means a simplified structure compared to the arrangement of a secondary interchangeable insert element in a primary interchangeable insert element.The interchangeable insert element comprising the two housing parts can, in turn, be arranged as the primary interchangeable insert element in the receptacle of an exhaust gas aftertreatment module. The first exhaust gas aftertreatment element in the first housing part and the second exhaust gas aftertreatment element in the second housing part are preferably designed differently. For example, it is possible for one of the exhaust gas aftertreatment elements to be designed as an oxidation catalyst and the other of the exhaust gas aftertreatment elements to be designed as a particulate filter.

[0026] Of course, further nesting of interchangeable insert elements and / or housing parts is also possible, for example, tertiary interchangeable insert elements, quaternary interchangeable insert elements and so on can be provided, or third housing parts, fourth housing parts and so on can be provided.

[0027] Preferably, the interchangeable insert element is arranged in the at least one receptacle.

[0028] In a preferred embodiment of the exhaust gas aftertreatment arrangement, the receptacle tapers in the direction of insertion of the interchangeable insert element. In particular, it is preferably conical in some regions. This ensures that the at least one sealing element and the at least one bearing element do not initially come into contact with an inner wall of the receptacle when the interchangeable insert element is inserted, but only touch this near an area provided for bearing and / or sealing, so that ultimately insertion against the friction present in the area of ​​the bearing element and / or the sealing element is only necessary over a comparatively short distance. This additionally facilitates assembly and disassembly of the insert element in the receptacle. In addition, the conical receptacle - as already explained - preferably serves for pressing and thus for a force-fitting fixation of the sealing element.

[0029] A preferred embodiment of the exhaust gas aftertreatment arrangement is characterized in that the at least one sealing element is arranged as an axial seal between an axial end face of the interchangeable insert element and an axial stop face of the receptacle. In this way, in particular, a skin leakage path extending in the flow direction of the exhaust gas flowing axially in the interchangeable insert element can be effectively and efficiently sealed.

[0030] Alternatively or additionally, it is preferably provided that the at least one sealing element is designed and arranged as a radial seal. In this case, it is particularly preferably arranged between an outer peripheral surface of the interchangeable insert element and an inner peripheral surface of the receptacle.

[0031] Particularly preferably, a first sealing element designed as an axial seal is provided, with a second sealing element designed as a radial seal being provided at the same time. An additional axial seal is advantageous in order to compensate for leaks resulting from shape and bearing tolerances of the radial seal and to block the main leakage path. It is particularly advantageous that the sealing effect of the axial seal increases with increasing exhaust gas volume flow. In particular, it is evident that with increasing volume flow - due to an increased load point of a machine upstream of the exhaust gas aftertreatment arrangement - the exhaust gas temperature also increases, resulting in thermal expansion of the replaceable insert element. This presses the insert element against the axial seal, thereby increasing its sealing effect.

[0032] A preferred embodiment of the exhaust gas aftertreatment arrangement is characterized in that the receptacle has a flow guide plate configured and arranged to deflect exhaust gas away from the bearing / sealing device and to direct an exhaust gas flow axially into the interchangeable insert element. The flow guide plate thus relieves the bearing / sealing device by deflecting the incoming exhaust gas away from the sealing assembly. This further increases the sealing effect of the bearing / sealing device. Preferably, the flow guide plate has the axial stop surface on which a sealing element designed as an axial seal is arranged.

[0033] Preferably, the flow guide plate is welded to the mount, whereby a circumferential weld seam may be provided. However, due to potential distortion, only partial welding is preferred, and the joint between the flow guide plate and the mount is positioned so that the exhaust gas flow does not directly impinge on the joint.

[0034] Another preferred embodiment of the exhaust gas aftertreatment arrangement is characterized in that it comprises an exhaust gas aftertreatment module with a removable insert element. In this case, the receptacle is arranged in particular on the exhaust gas aftertreatment module, with a primary removable insert element being inserted into the receptacle. Alternatively or additionally, the exhaust gas aftertreatment arrangement preferably comprises a primary removable insert element having a secondary removable insert element. In this case, the receptacle is arranged on the primary removable insert element, with a secondary removable insert element being inserted into the receptacle.

[0035] Particularly preferred is an embodiment of the exhaust gas aftertreatment arrangement, wherein the latter comprises an exhaust gas aftertreatment module with a receptacle into which a primary interchangeable insert element is inserted, wherein the primary interchangeable insert element, in turn, has a receptacle in which a secondary interchangeable insert element is arranged. Preferably, both the primary interchangeable insert element and the secondary interchangeable insert element each have a bearing / sealing device configured according to one of the previously described embodiments.

[0036] Another preferred embodiment of the exhaust gas aftertreatment arrangement is characterized in that the interchangeable insert element can be secured to the receptacle by means of a clamping clamp. In particular, a fixed bearing for the interchangeable insert element can be realized on the receptacle by means of the clamping clamp. The clamping clamp is preferably designed as a V-band clamping clamp with a clamping band. It is possible for the clamping clamp to be tightened and released by means of a screw connection. Alternatively or additionally, it is possible for the clamping clamp to have a clamping bracket for tightening and releasing. Preferably, a cover is held on the interchangeable insert element and / or the receptacle by means of the clamping clamp, which cover closes the interchangeable insert element and the receptacle.

[0037] A preferred embodiment of the exhaust gas aftertreatment arrangement is characterized in that the interchangeable insert element has a cover that simultaneously serves to close the exhaust gas aftertreatment module and the interchangeable insert element. The interchangeable insert element, which extends into the exhaust gas aftertreatment module, is preferably held on an external flange of the same and secured there by means of the cover and preferably a clamping device.

[0038] Alternatively, the cover of the removable insert element can serve to close the receptacle and the removable insert element within the exhaust gas aftertreatment module. In this case, the removable insert element as a whole – including the cover – is arranged in the exhaust gas aftertreatment module, which in turn is accessible to the outside via a maintenance opening and is closed there with another cover. The arrangement of the removable insert element within the exhaust gas aftertreatment module reduces the sealing requirements because there is no system boundary to the environment. Preferably, the removable insert element arranged in the exhaust gas aftertreatment module is also held to the receptacle together with the cover by means of a clamp.This clamp preferably has a clamping bracket because, due to the increased contamination from exhaust gas flowing around the interchangeable insert element and the clamping bracket, a screw in the clamping bracket can stick or cake, making it difficult to loosen without the clamping bracket.

[0039] However, it is also possible for the removable insert element located in the exhaust aftertreatment module to be secured to the mount without a cover, simply by means of a clamp. Depending on the design of the exhaust aftertreatment module, no cover is required in this case, so it can be advantageously dispensed with.

[0040] According to the invention, a flexible support element for compensating for thermal linear expansion is arranged in series with the at least one sealing element designed as an axial seal. In this exemplary embodiment, the bearing / sealing device therefore has at least one sealing element designed as an axial seal, with the flexible support element arranged in series with this. The flexible support element and the sealing element are preferably arranged directly adjacent - viewed in the axial direction and preferably in this order - one behind the other between the axial stop surface of the receptacle and the axial end surface of the interchangeable insert element. The flexible support element is preferably designed as a wire mesh ring with medium or low spring force to compensate for thermal expansion, but it is also possible for the flexible support element to be designed as an elastomer element or to have at least one disc spring.In this case, the sealing element can be designed as a flat gasket or a textile gasket, particularly one with high rigidity. The axial stop surface may have a perforation to support the contact force.

[0041] The object is also achieved by providing an exhaust system for an internal combustion engine, which has an exhaust aftertreatment arrangement according to one of the previously described embodiments. In particular, it is possible for the exhaust system to have an exhaust aftertreatment module according to one of the previously described embodiments. In connection with the exhaust system, the advantages already explained in connection with the interchangeable insert element and the exhaust aftertreatment arrangement arise in particular.

[0042] The object is finally also achieved by providing an internal combustion engine having an exhaust aftertreatment arrangement according to one of the previously described embodiments. The internal combustion engine preferably has an exhaust aftertreatment module according to one of the previously described embodiments. In particular, the internal combustion engine preferably has an exhaust system according to one of the previously described embodiments. In connection with the internal combustion engine, the advantages already explained in connection with the interchangeable insert element, the exhaust aftertreatment arrangement, and the exhaust system are particularly advantageous.

[0043] The internal combustion engine is preferably designed as a reciprocating piston engine. It is possible for the internal combustion engine to be configured to drive a passenger car, a truck, or a commercial vehicle. In a preferred embodiment, the internal combustion engine is used, in particular, to drive heavy land or water vehicles, for example, mining vehicles, trains (where the internal combustion engine is used in a locomotive or railcar), or ships. It is also possible to use the internal combustion engine to drive a defense vehicle, for example, a tank. One embodiment of the internal combustion engine is preferably also used stationary, for example, for stationary energy supply in emergency power operation, continuous load operation, or peak load operation, wherein the internal combustion engine in this case preferably drives a generator.Stationary application of the internal combustion engine to drive auxiliary units, for example fire pumps on drilling platforms, is also possible. Furthermore, application of the internal combustion engine in the extraction of fossil raw materials and in particular fuels, for example oil and / or gas, is possible. Use of the internal combustion engine in the industrial sector or in the construction sector, for example in a construction or building machine, for example in a crane or an excavator, is also possible. The internal combustion engine is preferably designed as a diesel engine, a gasoline engine, a gas engine for operation with natural gas, biogas, special gas or another suitable gas. In particular, if the internal combustion engine is designed as a gas engine, it is suitable for use in a combined heat and power plant for stationary energy generation.

[0044] The invention is explained in more detail below with reference to the drawings, which show: Fig. 1 is a schematic exploded view of a first example of an internal combustion engine with an exhaust system and an exhaust aftertreatment arrangement; Fig. 2 a schematic partial sectional view of the first example of an exhaust aftertreatment arrangement; Fig. 3 a schematic detailed representation of an example of a sealing element; Fig. 4 is a schematic partial sectional view of a second example of an exhaust gas aftertreatment arrangement not belonging to the invention; Fig. 5 a schematic partial sectional view of a third example of an exhaust gas aftertreatment arrangement not belonging to the invention, and Fig. 6 a schematic partial sectional view of an embodiment of an exhaust gas aftertreatment arrangement.

[0045] Fig. 1 shows a schematic exploded view of an example not belonging to the invention of an internal combustion engine 1 with an exhaust system 3, which has an exhaust gas aftertreatment arrangement 5. The exhaust gas aftertreatment arrangement 5 here has an exhaust gas aftertreatment module 7, which is designed as an exhaust box and has a plurality of receptacles 9, here exactly four receptacles 9, for interchangeable insert elements, wherein two interchangeable insert elements are shown in an exploded view, namely a primary interchangeable insert element 11 and a secondary interchangeable insert element 13. The primary interchangeable insert element 11 can be received in one of the receptacles 9, wherein it in turn has a receptacle (not shown) in which the secondary interchangeable insert element 13 can be received.The secondary interchangeable insert element 13 can therefore be inserted in particular into the primary interchangeable insert element 11, wherein the primary interchangeable insert element 11 can in turn be inserted into the receptacle 9 of the exhaust gas aftertreatment module 7.

[0046] The interchangeable insert elements 11, 13 can be closed off from the surroundings of the exhaust aftertreatment module 7 by a cover 15, wherein the cover 15 can be held to the interchangeable insert elements 11, 13, and these can simultaneously be held to the receptacle 9, by a clamp 17. The clamp 17 is designed in particular as a V-band clamp with a clamping band.

[0047] Each of the interchangeable insert elements 11, 13 has an exhaust gas aftertreatment element (not shown). For example, it is possible for an oxidation catalyst to be arranged in the primary interchangeable insert element 11, and a particulate filter element to be arranged in the secondary interchangeable insert element 13. An exhaust gas flow within the exhaust gas aftertreatment module 7 preferably runs such that the exhaust gas flows into the interchangeable insert elements 11, 13 in an axial direction, in particular counter to the insertion direction of the interchangeable insert elements 11, 13, from a side facing the interior of the exhaust gas aftertreatment module 7 and leaves them again through radial bores 19 within the exhaust gas aftertreatment module 7.

[0048] The primary interchangeable insert element 11 has a first bearing / sealing device 21 for its mounting and sealing in the receptacle 9 of the exhaust aftertreatment module 7. The secondary interchangeable insert element 13 has a second bearing / sealing device 23 for its mounting and sealing in the receptacle (not shown) of the primary interchangeable insert element 11.

[0049] Fig. 2 shows a schematic partial sectional view of the first example not belonging to the invention of an exhaust gas aftertreatment module 7 according to Fig. 1. Identical and functionally equivalent elements are provided with the same reference numerals, so that reference is made to the previous description in this regard. Here, it is shown that the receptacle 9 has a holding tube 25 into which the primary interchangeable insert element 11 is inserted. Also shown is the first exhaust gas aftertreatment element 27, which has the primary interchangeable insert element 11. Furthermore, the design of the first bearing / sealing device 21 of the primary interchangeable insert element 11 is shown in detail. This device has a bearing element 29 and a first sealing element 31 separate from the bearing element 29. The functions of bearing on the one hand and sealing on the other of the interchangeable insert element 11 in the receptacle 9 are therefore performed here by two separate elements, namely the bearing element 29 and the sealing element 31.These are arranged here - viewed in the axial direction - directly behind or next to one another. The bearing element 29 is preferably designed as a wire mesh ring or as a wire mesh band and, in particular with regard to its outer diameter with respect to an inner diameter of the holding tube 25, is designed with close tolerances in a bearing area, thus in an area in which the first bearing / sealing device 21 is intended to be arranged when the interchangeable insert element 11 is installed. The first sealing element 31 is preferably designed as an elastic seal, in particular as an elastic sealing band. In the exemplary embodiment illustrated here, the first sealing element 31 is designed in particular as a radial seal. It lies tightly between an outer circumferential surface 33 of the primary interchangeable insert element 11 and an inner circumferential surface 35 of the receptacle 9.In this case, the first sealing element 31 is in particular more compressible and designed with a higher elasticity than the bearing element 29 and at the same time is oversized with regard to an outer diameter, so that on the one hand it can be easily inserted into the holding tube 25 due to its high elasticity and compressibility and on the other hand it develops an efficient sealing effect.

[0050] It also shows that the receptacle 9, specifically the holding tube 25 here, tapers in some areas in the insertion direction, so that the first sealing element 31 and the bearing element 29 only come into contact with the inner circumferential surface 35 near their final assembly position. This significantly facilitates the assembly and disassembly of the primary interchangeable insert element 11 in the receptacle 9. At the same time, the preferably conical taper of the holding tube 25 acts as an insertion and centering aid.

[0051] In the embodiment shown here, the first bearing / sealing device 21 also has a second sealing element 37, which is designed as an axial seal. The axial seal is tightly located between an axial end surface 39 of the primary interchangeable insert element 11 and an axial stop surface 41 of the receptacle 9. The second sealing element 37 improves the sealing effect of the first bearing / sealing device 21 and, in particular, seals a main leakage path.

[0052] The receptacle 9 also has a flow guide plate 43, which is designed and arranged to deflect exhaust gas flowing in in the direction of an arrow P away from the bearing / sealing device 21, and to direct the exhaust gas flow axially into the interchangeable insert element 11. In particular, this prevents direct flow against the first sealing element 31, thus relieving the load on the sealing assembly. In addition, the flow guide plate 43 has the axial stop surface 41 and thus serves to accommodate the second sealing element 37. This compensates for leakage resulting from the shape and position tolerance of the first sealing element 31 and blocks a main leakage path. In particular, it is also evident that the sealing effect of the second sealing element 37 increases with increasing exhaust gas volume flow. Furthermore, manufacturing-related leakage points are eliminated, in particular by the second sealing element 37.

[0053] A particularly high degree of tightness is achieved if the flow guide plate 43 is welded to the holding tube 25, preferably by means of a circumferential weld seam 45 or particularly preferably by partial welding in order to avoid distortions and / or deformations.

[0054] In Fig. 2 also partially shows the secondary interchangeable insert element 13, which is inserted into a receptacle 47 of the primary interchangeable insert element 11. Also shown is a second exhaust aftertreatment element 49, which has the secondary interchangeable insert element 13 and is preferably designed as a particulate filter element. Furthermore, the second bearing / sealing device 23 of the secondary interchangeable insert element 13 is also shown. It can be seen that the structure of the receptacle 47 and the second bearing / sealing device 23 in the preferred embodiment shown here is completely analogous to the corresponding structure of the first receptacle 9 and the first bearing / sealing device 21.In order to avoid repetition, the equivalent elements of the second bearing / sealing device 23 and the second receptacle 47 are therefore provided with primed reference numerals in comparison to the first receptacle 9 and the first bearing / sealing device 21, wherein reference is otherwise made to the detailed, previous description of the first receptacle 9 and the first bearing / sealing device 21. In particular, a bearing element 29', a first sealing element 31', which is designed as a radial seal, a second sealing element 37', which is designed as an axial seal, and a flow guide element 43' are also provided here, which is preferably connected to a housing part of the primary interchangeable insert element 11 via a weld seam 45'. The second receptacle 47 has a holding tube 25', which here is on the right in . Fig. 2 it has just been indicated that this also preferably tapers in the insertion direction of the secondary interchangeable insert element 13.

[0055] The first sealing elements 31, 31' are preferably designed as a sealing tape and are wound around the interchangeable insert elements 11, 13 assigned to them. They are particularly preferably designed as self-adhesive seals, wherein a double-sided adhesive tape can be arranged, in particular, on an underside of the sealing elements 31, 31'. The design as a self-adhesive seal allows the sealing elements 31, 31' to be fixed, particularly for the purpose of insertion and thus to facilitate assembly. However, it has been shown that winding a sealing tape creates a joint that essentially represents a leakage path.

[0056] Fig. 3 shows a schematic representation of a top view of a circumference of the sealing element 31, wherein the sealing element 31' of the secondary interchangeable insert element 13 is preferably of identical design. In the region of a joint 51 resulting in the circumferential direction, a first end 53 has a projection 55 which, in the assembled state, extends into a recess 57 at a second end 59 of the sealing element 31. In this way, a so-called mat joint or labyrinth joint is realized, which enables a high sealing effect by avoiding a continuous gap. At the same time, this design of the joint 51 serves to compensate for manufacturing tolerances and thermomechanical effects.

[0057] Alternatively, two sealing elements, each with a butt joint, can be used, with the joints arranged offset from one another in the circumferential direction. Alternatively or additionally, an extended sealing element is also conceivable, with a first end of the sealing element overlapping a second end or being fixed offset from it to create a labyrinth joint.

[0058] The projection 55 extends in the circumferential direction, with the recess 57 also extending into the second end 59 in the circumferential direction. As already explained, the projection 55 engages the recess 57 when the sealing element 31 is in the assembled state.

[0059] Fig. 4 shows a schematic detailed representation of a second example of an exhaust gas aftertreatment arrangement 5 with an exhaust gas aftertreatment module 7, not belonging to the invention. Identical and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description in this respect. In this exemplary embodiment, only a primary interchangeable insert element 11 is provided, which, however, has a first housing part 61 and a second housing part 63, wherein the first exhaust gas aftertreatment element 27 is provided in the first housing part 61 and the second exhaust gas aftertreatment element 49 is provided in the second housing part 63. The two housing parts 61, 63 are detachably connected to one another at a connection point 65, preferably screwed together. This creates a uniform insert with a desired separation point, namely the connection point 65, as the primary interchangeable insert element 11.Thus, in particular, the second bearing / sealing device 23 can be omitted. Only the first bearing / sealing device 21 is then required.

[0060] However, the removable insert element 11 is preferably additionally supported in the receptacle 9 by an outer bearing element 67 and sealed by an outer sealing element 69. However, the outer bearing and sealing elements 67, 69 can preferably be inserted after the removable insert element 11 has been inserted into the receptacle 9, optionally also through the radial bores 19—particularly if they are designed as a bearing strip and a sealing strip. Also shown are the cover 15 and the clamp 17, with which the removable insert element 11 is secured to the receptacle 9. In this case, the cover 15 serves, in particular, as a closure for an exhaust gas aftertreatment module 7, thus in particular as a seal against its external environment. At the same time, the cover 15, together with the clamp 17 and the receptacle 9, forms a fixed bearing for the removable insert element 11.Another advantage of the design shown here is that the outer bearing element 67 and the outer sealing element 69 can be positioned comparatively close - viewed in the direction of insertion - to the fixed bearing designed in this way, which results in an improved sealing effect due to less expansion when heated between the location of the fixed bearing and the location of the outer bearing element 67 and the outer sealing element 69. At the same time, the exemplary embodiment shown here is particularly space-saving, in particular since the second bearing / sealing device 23 is omitted. A further advantage is that the elements 67, 69 may have to be inserted over a shorter distance, which reduces the risk of damage or slipping during insertion. The outer bearing and sealing elements 67, 69 can also be arranged in a different way, in particular swapped over one another, than shown in FIG. Fig. 4 be arranged.

[0061] Fig. 5 shows a schematic partial sectional view of a third example of an exhaust gas aftertreatment arrangement 5 with an exhaust gas aftertreatment module 7, not belonging to the invention. Identical and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description in this respect. It can be seen here that the interchangeable insert element 11 is arranged in an interior 71 of the exhaust gas aftertreatment module 7, namely completely together with the cover 15 and the clamp 17, wherein the cover 15 serves to close the receptacle 9 within the interior 71 of the exhaust gas aftertreatment module 7. However, the cover 15 can also be omitted, in which case the exhaust gas aftertreatment module 7 is only secured with the clamp 17. The exhaust gas aftertreatment module 7, in turn, is closed off from the outside environment by an outer cover 73. This outer cover 73 serves only as maintenance access here.It does not provide a fixed bearing for the interchangeable insert element 11. Rather, this is provided if necessary by the cover 15 and in any case the clamping clamp 17. The embodiment shown here is advantageous because lower requirements can be placed on the sealing in the area of ​​the clamping clamp 17 and if necessary the cover 15, because there is no seal against an external environment, but only against the interior 71 of the exhaust gas aftertreatment module 7. The clamping clamp 17 preferably has - in addition to a clamping screw - a clamping bracket to ensure easy operation even when dirty due to being arranged in the exhaust gas area. A further advantage of the clamping clamp 17 is the high normal force that can be exerted on a flat gasket, which provides a particularly good sealing effect. Overall, the embodiment shown here results in reduced expenditure with regard to sealing and bearings.

[0062] Fig.6 shows a schematic partial sectional view of an exemplary embodiment of an exhaust gas aftertreatment arrangement 5 with an exhaust gas aftertreatment module 5. Identical and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description in this respect. It can be seen here that, according to the invention, a flexible support element 75 is arranged in series with the second sealing element 37 serving as an axial seal, in particular axially directly adjacent to it and preferably in front of it as seen in the insertion direction. The second sealing element 37 is preferably designed as a seal with high rigidity, in particular as a textile seal. The support element 75 is preferably designed as a wire mesh ring with medium or low spring force to compensate for thermal expansion.It is possible that the flow guide plate 43 is perforated in the region of the axial stop surface 41 in order to support the contact pressure on the arrangement of the support element 75 and the second sealing element 37.

[0063] The configuration shown here is only explicitly explained for the first bearing / sealing device 21. However, it is expressly pointed out that a corresponding configuration is also possible additionally or alternatively for the second bearing / sealing device 23.

[0064] Overall, it can be seen that the interchangeable insert element 11, 13 presented here of the exhaust aftertreatment assembly 5, the exhaust system 3, and the internal combustion engine 1 significantly increases the sealing effect and, in particular, the particle retention rate, while simultaneously simplifying assembly and disassembly of the interchangeable insert element. Thus, not only is the conflict of objectives described above eliminated, but the overall tightness of the exhaust system is also further increased.

Claims

[1] Exhaust gas aftertreatment arrangement (5) with at least one receptacle (9, 47) for an interchangeable insert element (11, 13), and with an interchangeable insert element (11, 13) which has a bearing / sealing device (21, 23) for supporting and sealing the interchangeable insert element (11, 13) in the receptacle (9, 47) for the interchangeable insert element (11, 13), wherein the bearing / sealing device (21, 23) has at least one bearing element (29) and at least one sealing element (31, 37) separate from the bearing element (29), characterized by that a flexible support element (75) for compensating for thermal linear expansion is arranged in series with the at least one sealing element (37) designed as an axial seal. [2] Exhaust aftertreatment arrangement (5) according to claim 1, characterized by that the bearing element (29) is designed as a wire mesh ring or as a wire mesh band. [3] Exhaust aftertreatment arrangement (5) according to one of the preceding claims, characterized bythat the at least one sealing element (31, 37) is designed as an elastic seal. [4] Exhaust aftertreatment arrangement (5) according to one of the preceding claims, characterized by that the interchangeable insert element (11, 13) is designed as a primary interchangeable insert element (11) for arrangement in the receptacle (9) of an exhaust gas aftertreatment module (7), or as a secondary interchangeable insert element (13) for arrangement in the receptacle (47) of a primary interchangeable insert element (11). [5] Exhaust aftertreatment arrangement (5) according to one of the preceding claims, characterized by that the interchangeable insert element (11) has a first housing part (61) with a first exhaust gas aftertreatment element (27), which is detachably connected to a second housing part (63) with a second exhaust gas aftertreatment element (49). [6] Exhaust aftertreatment arrangement (5) according to one of the preceding claims, characterized bythat the at least one sealing element (31, 37) is arranged as an axial seal between an axial end surface (39) of the interchangeable insert element (11, 13) and an axial stop surface (41) of the receptacle (9, 47), and / or that the at least one sealing element (31, 37) is designed and arranged as a radial seal. [7] Exhaust aftertreatment arrangement (5) according to one of the preceding claims, characterized by in that the receptacle (9, 47) has a flow guide plate (43) which is designed and arranged to deflect exhaust gas away from the bearing / sealing device (21, 23) and to direct an exhaust gas flow axially into the interchangeable insert element (11, 13). [8] Exhaust aftertreatment arrangement (5) according to one of claims 4 to 7, characterized bythat the exhaust gas aftertreatment arrangement (5) has the exhaust gas aftertreatment module (7) with the interchangeable insert element (11) and / or the primary interchangeable insert element (11) with the secondary interchangeable insert element (13). [9] Exhaust aftertreatment arrangement (5) according to one of the preceding claims, characterized by that the interchangeable insert element (11, 13) can be fixed to the holder (9, 47) by means of a clamp (17). [10] Exhaust aftertreatment arrangement (5) according to one of the preceding claims, characterized by that the interchangeable insert element (11, 13) has a cover (15) which simultaneously serves to close the exhaust gas aftertreatment module (7) or to close the receptacle (9, 47) within the exhaust gas aftertreatment module (7). [11] Exhaust system (3) for an internal combustion engine (1), with an exhaust aftertreatment arrangement (5) according to one of claims 1 to 10. [12] Internal combustion engine (1) with an exhaust gas aftertreatment arrangement (5) according to one of claims 1 to 10.

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