Exhaust aftertreatment system and cartridge

Abstract

Exhaust aftertreatment device for an exhaust system of an internal combustion engine, - with a housing (2) in which at least one receiving tube (3) is arranged, which contains a receiving space (4), - with at least one cartridge (5) which is arranged in the receiving space (4) in an exchangeable manner and which has a cartridge tube (6) and at least one exhaust gas aftertreatment element (7) arranged in the cartridge tube (6), - wherein the cartridge tube (6) is supported axially on an annular step (9) at least on one axial end face (31) via at least one spring element (27) under axial prestress, characterized in that the spring element (27) has at least one clamping region (34) which engages around the end face (31) of the cartridge tube (6) and fixes the spring element (27) to the cartridge tube (6) by clamping, or at least one clip region (36) into which an inwardly angled collar (37) of the cartridge tube (6) is axially clipped.

Description

[0001] The present invention relates to an exhaust aftertreatment device for an exhaust system of an internal combustion engine according to the preamble of claim 1, which can be arranged, for example, in a motor vehicle. The invention also relates to a cartridge for such an exhaust aftertreatment device.

[0002] Exhaust systems for internal combustion engines can, in a known manner, comprise silencers and exhaust gas purification devices, such as catalytic converters and particulate filters. An exhaust gas aftertreatment device used in this case can be specialized for a single exhaust gas aftertreatment function. Combined devices are also known in which at least two different functions are realized, such as a particulate filter in combination with a catalytic converter, wherein a sound-damping effect can also be integrated. Particularly in more complex exhaust gas aftertreatment systems that contain a particulate filter element, provision can be made for the particulate filter element to be replaced at least once during the service life of the exhaust system. For this purpose, the respective particulate filter element must be arranged in an interchangeable manner within the exhaust gas aftertreatment device.The same applies in principle to other exhaust gas aftertreatment elements such as SCR catalysts, oxidation catalysts and other catalysts.

[0003] For this purpose, an exhaust gas aftertreatment device is known from DE 101 44 613 A1, for example, which has a housing in which at least one receiving tube is arranged, which contains a receiving space. Furthermore, the exhaust gas aftertreatment device can have at least one cartridge, which is arranged replaceably in the receiving space and which has a cartridge tube and at least one exhaust gas aftertreatment element arranged in the cartridge tube. In the known exhaust gas aftertreatment device, the cartridge tube is supported on an axial end face by a spring element in the form of an elastic seal under axial preload on an annular step.

[0004] To replace the exhaust aftertreatment element, the entire cartridge can now be simply pulled out of the receiving tube with the housing open and replaced with a new cartridge, which is then inserted into the receiving tube. The use of such cartridges simplifies the replacement of the respective exhaust aftertreatment element, since the mounting of the respective exhaust aftertreatment element within the cartridge tube can be realized in a conventional manner, for example, using a radially pressed bearing mat. This allows, in particular, conventional canning of the exhaust aftertreatment element, bearing mat, and cartridge tube to be carried out to produce such a cartridge.

[0005] A problem with such exhaust aftertreatment systems is the fact that, during operation of the exhaust aftertreatment system, a bypass flow can form radially between the cartridge tube and the receiving tube, bypassing an exhaust flow path intended for the exhaust gas purification function and passing through the respective exhaust aftertreatment element. This reduces the efficiency of the exhaust gas purification effect. On the other hand, it can cause contaminants to accumulate in an annular space formed radially between the cartridge tube and the receiving tube, making it difficult to remove the cartridge from the receiving space during maintenance.

[0006] From DE 10 2012 207 960 B3 it is known to attach a spring element to the free end of a cartridge tube, which spring element interacts with the receiving tube in the radial direction.

[0007] The present invention addresses the problem of providing an improved embodiment for an exhaust gas aftertreatment device of the type described above, which is characterized in particular by improved cartridge replaceability. In particular, the aim is to avoid said bypass flow.

[0008] This problem is solved according to the invention by the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims.

[0009] The invention is based on the general idea of ​​axially supporting the cartridge under axial preload on an annular step that is stationary with respect to the receiving space. This axial preload can be used to reduce the forces required to withdraw the cartridge from the receiving space during maintenance. According to the invention, at least one spring element is used to generate such preload. Preferably, the respective spring element is arranged such that the axial preload is oriented in a cartridge extraction direction, i.e., opposite to an insertion direction in which the cartridge is inserted into the receiving tube.

[0010] Generally, this is achieved by supporting the cartridge tube axially on an annular step at least at one axial end face via at least one spring element under axial preload. This annular step is fixedly arranged in the housing. Preferably, this annular step is firmly connected to the receiving tube. In particular, the annular step can be permanently attached to the receiving tube as a separate component, e.g., by soldering or welding, or can be integrally formed on the receiving tube.

[0011] It is clear that a plurality of exhaust gas aftertreatment elements can also be arranged in the cartridge tube. However, preference is given to accommodating a single, in particular monolithic, preferably ceramic, exhaust gas aftertreatment element. The exhaust gas aftertreatment element held in the cartridge is preferably a particulate filter element. In principle, however, it can also be a catalyst element, e.g., an oxidation catalyst or an SCR catalyst. A particulate filter element with a catalytically active coating is also conceivable. Furthermore, it is also conceivable to arrange various exhaust gas aftertreatment elements one behind the other in the cartridge tube, e.g., a catalyst element and, downstream of it, a particulate filter element. If the exhaust gas aftertreatment element is a particulate filter element, the cartridge can also be referred to as a particulate filter cartridge.However, if the exhaust aftertreatment element is a catalyst element, the cartridge can also be called a catalyst cartridge.

[0012] A particularly advantageous embodiment is one in which the spring element is designed in a ring-shaped, circumferential manner. This design allows the preload to be applied to the cartridge evenly distributed in the circumferential direction. Furthermore, a single ring-shaped spring element is generally sufficient to achieve the desired preload. However, this does not preclude embodiments in which multiple spring elements are used. With appropriate design and arrangement, such an annular spring element also exerts a certain sealing effect. Thus, the use of an annular, closed-circumferential spring element can also be used to reduce or prevent a bypass flow that bypasses an exhaust gas flow path passing through the particulate filter element.

[0013] According to a particularly advantageous development, the spring element can be arranged such that it seals the exhaust gas flow path passing through the particulate filter element against the aforementioned annular space formed radially between the cartridge tube and the receiving tube. The sealing effect of the spring element can significantly reduce and, ideally, even completely eliminate unwanted bypass flow. The reduced or eliminated bypass flow also reduces deposits and contaminants in the annular space, which also contributes to facilitating cartridge replacement. Independently of this, the achieved sealing effect leads to improved efficiency of the particulate filter element or exhaust aftertreatment system with regard to its particulate filter function.

[0014] According to a practical development, the spring element can rest in a closed, ring-shaped circumferential manner on the cartridge tube and / or in a closed, ring-shaped circumferential manner on the annular step. A linear contact or contact of the spring element on the cartridge tube and / or on the annular step is particularly advantageous. The linear and pre-tensioned contact results in an efficient sealing effect between the spring element and the annular step on the one hand and / or between the spring element and the cartridge tube on the other. The spring element can thus efficiently seal the annular space against the exhaust gas flow path. Such a linear contact can be realized, for example, by a convexly curved profile on the spring element in the contact area or a bead-shaped elevation on the spring element in the contact area.

[0015] In another embodiment, the spring element can have at least one radially outwardly projecting guide contour that is radially supported on the receiving tube. This results in centering of the cartridge tube in the receiving tube in the region of the spring element. The guide contour can be designed in a ring-shaped, circumferential manner or be formed by a plurality of local guide contour elements spaced apart from one another in the circumferential direction. The guide contour is expediently formed integrally on the spring element. Furthermore, the guide contour can be arranged in an end section of the cartridge tube that has the end face of the cartridge tube. The integrated variant with a closed, circumferential guide contour is preferred, since in this case the guide contour also improves the sealing effect.

[0016] Furthermore, the spring element can have at least one radial support contour axially adjacent to the guide contour, which is radially supported on the cartridge tube. This support contour can also expediently be formed integrally on the spring element. Additionally or alternatively, this radial support contour can be designed in a ring-shaped, circumferential manner and, in particular, have a linear contact on the cartridge tube. Furthermore, the support contour is expediently supported on a side of the guide contour on the cartridge tube facing away from the end face of the cartridge tube. Here, too, such a linear contact can be realized, for example, by a convexly curved profile on the spring element in the contact area or a bead-shaped elevation on the spring element in the contact area.

[0017] Particularly advantageously, the guide contour can be arranged radially between the cartridge tube and the receiving tube, whereby the aforementioned annular space is used to accommodate the guide contour or to implement the centering function. Alternatively, the guide contour can be arranged axially between an axial end face of the cartridge tube and the annular step. This provides more adjustment range for the radial centering of the cartridge tube within the receiving tube, which simplifies centering even with larger manufacturing tolerances.

[0018] According to a first solution according to the invention, the spring element has at least one clamping area that encompasses one end face of the cartridge tube and clamps the spring element to the cartridge tube. The fixation of the spring element to the cartridge tube results in the spring element being simultaneously pulled out of the receiving space when the cartridge is pulled out. In particular, the spring element can thus be replaced simultaneously with the cartridge during maintenance. For this purpose, the spring element is expediently pre-assembled on the respective cartridge, so that it essentially forms a component of the cartridge.

[0019] The clamping area can, for example, be designed as a pocket into which an end section of the cartridge tube, which has the front end, is axially inserted. This results in a particularly efficient radial clamping of the end section in the clamping area.

[0020] The clamping area or pocket can be designed to be ring-shaped and circumferential. The clamping area or pocket is preferably formed integrally with the spring element.

[0021] According to a second solution according to the invention, the spring element has at least one clip region into which an inwardly angled collar of the cartridge tube is axially clipped. Here, too, the spring element is fixed to the cartridge tube in order to be able to pull the filter element out of the receiving space simultaneously with the rest of the cartridge in the event of maintenance. Furthermore, the fixation of the spring element to the cartridge tube creates a predetermined relative position between the spring element and the cartridge tube. Here, too, the clip region can expediently be designed in a ring-shaped manner. Additionally or alternatively, the clip region can be formed integrally on the spring element. The wording "inward" refers to the radial direction; in other words, the collar points radially inward. The collar is preferably angled by 90° relative to the cartridge tube.In principle, however, other angles that are larger or smaller than 90° are also conceivable.

[0022] According to a further development, the clip region can have a holding region that encompasses an inner edge of the collar. This achieves an efficient, positive-locking fixation in the axial direction between the spring element and the cartridge tube in a particularly simple manner. For example, the holding region can be S-shaped in a longitudinal section of the spring element. Such a longitudinal section lies in a plane in which a longitudinal center axis of the cartridge also lies. Here, too, the holding region is expediently formed integrally with the clip region or integral spring element.

[0023] According to another advantageous development, the clip region can have at least one locking contour, which cooperates with a counter-locking contour formed on the collar and complementary to the locking contour for fixing or positioning the collar on the clip region. For example, the locking contour is an axially projecting projection. The complementary counter-locking contour is then a corresponding recess. Likewise, the locking contour can be a recess, while the counter-locking contour is formed by a complementary projection. Said locking contour can be configured in a point-like manner, i.e., have several locking contour elements distributed in the circumferential direction. However, an annular configuration of the locking contour is preferred, whereby the aforementioned sealing effect can be improved. Here, too, an integral design is preferred, so that the locking contour is integrally formed on the clip region or on the spring element.

[0024] In another advantageous embodiment, the spring element can have at least one axially resilient spring region extending axially between the end face and the wall. Here, too, the spring region is expediently formed integrally on the spring element. With the help of this axially resilient spring region, the spring element can elastically compensate for thermally induced expansion effects that lead to different length changes on the receiving tube and the cartridge tube, without excessive stresses occurring. At the same time, a sealing effect, possibly realized with the spring element, can be ensured over the entire expected temperature range of the exhaust gas aftertreatment system, since the spring element can elastically follow any relative movements that may occur and always rests preloaded against the annular step and the cartridge tube.

[0025] In an advantageous further development, the spring region can have a wave or corrugated structure in the longitudinal section of the spring element. Here, too, the longitudinal section lies in a sectional plane in which the longitudinal center axis of the cartridge also lies. Such a wave structure makes the spring element axially resilient over a comparatively large adjustment range. The spring element is thus shaped like a corrugated bellows within the spring element. The spring element is expediently made of a metal, preferably spring steel.

[0026] In another advantageous embodiment, the spring element can have a support region with which the spring element is supported axially on the annular step and which has at least one locking contour which cooperates with a counter-locking contour formed on the annular step and complementary to the locking contour for the radial fixing or radial positioning of the spring element on the annular step. Here too, a desired relative position between the spring element and the annular step, in particular a radial centering of the spring element relative to the annular step, can be achieved. Furthermore, here too, the locking contour can be formed, for example, by an axially projecting projection, while the complementary counter-locking contour is formed by a corresponding axial recess. Here, too, the reverse case is possible, in which the locking contour is formed by an axial recess, while the counter-locking contour then has an axial projection.The locking contour is preferably designed to be completely circular in the circumferential direction. A point-based distribution of the locking contour in the circumferential direction is also conceivable, for example, in the form of separate locking contour elements. Furthermore, integration of the locking contour into the spring element is also preferred.

[0027] In another embodiment, the annular step on the receiving tube can be fixedly arranged axially opposite an insertion opening for inserting the cartridge into the receiving space. For example, the annular step can be formed integrally on the receiving tube. It can also be welded or soldered thereto. Furthermore, the insertion opening of the receiving tube is arranged within the housing and is axially spaced from and axially aligned with a housing opening through which the cartridge can be inserted into the insertion opening. The housing opening can then expediently be closed with a closure device that can be removed for changing the cartridge. This closure device is supported axially on the cartridge or cartridge tube and presses the cartridge or cartridge tube into the receiving space against the preload of the spring element.This design allows the cartridge to be easily integrated into the exhaust gas flow path within the housing. Furthermore, during maintenance, the counterforce acting on the spring element is removed when the closure device is removed, allowing the spring element to push the cartridge out of the receiving space, making it easier to remove the cartridge from the receiving tube.

[0028] In a particularly advantageous development, the aforementioned closure device can have a cover for closing the housing opening and a support ring that is axially supported on the cartridge or cartridge tube and through which exhaust gas can flow radially. For example, a circumferential edge of the support ring can be perforated for this purpose. It is also conceivable for the support ring to be supported on the cartridge or cartridge tube via several axial webs distributed in the circumferential direction, so that there is sufficient free space in the circumferential direction between adjacent webs through which exhaust gas can flow.

[0029] A cartridge according to the invention thus comprises a cartridge tube for replaceable insertion of the cartridge into a receiving tube of the exhaust gas aftertreatment device and at least one exhaust gas aftertreatment element arranged in the cartridge tube. The cartridge can preferably also have at least one spring element on an axial end face of the cartridge tube, which is provided for axially supporting the cartridge tube under axial preload on an annular step of the exhaust gas aftertreatment device when the cartridge is inserted into the receiving tube. Additionally or alternatively, an axial end face of the cartridge tube can have an inwardly angled collar, against which at least one spring element can be supported under axial preload when the cartridge is inserted into the receiving tube.

[0030] Further important features and advantages of the invention emerge from the subclaims, from the drawings and from the associated description of the figures based on the drawings.

[0031] It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

[0032] Preferred embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description, wherein the same reference numerals refer to the same or similar or functionally identical components.

[0033] They show, schematically, Fig. 1 a longitudinal section of an exhaust aftertreatment device in the area of ​​a cartridge, Fig. 2 a longitudinal section as in Fig. 1, but in exploded view in the area of ​​the cartridge, Fig. 3 an enlarged detail III from Fig. 1 in the area of ​​a spring element, Fig. 4 to 6 detailed views as in Fig. 3, but with other embodiments.

[0034] According to the Fig. 1 and Fig. 2 comprises an exhaust gas aftertreatment device 1, which is suitable for use in an exhaust system (not shown here) of an internal combustion engine, preferably of a motor vehicle, a housing 2, in which at least one receiving tube 3 is arranged, which contains a receiving space 4. The exhaust gas aftertreatment device 1 also has at least one cartridge 5, which has a cartridge tube 6 and at least one exhaust gas aftertreatment element 7 arranged in the cartridge tube 6. In the example shown here, a particle filter element is provided as the exhaust gas aftertreatment element 7, so that the exhaust gas aftertreatment element 7 can also be referred to as a particle filter element 7 below. In an alternative embodiment, which is not shown here, the exhaust gas aftertreatment element 7 can also be a catalyst element, such asan oxidation catalyst element or an SCR catalyst element, where SCR stands for “Selective Catalytic Reduction” in the known manner.

[0035] The respective particle filter element 7 is expediently mounted and axially fixed in the cartridge tube 6 by means of a bearing mat 8. For this purpose, the bearing mat 8 is regularly pressed radially between the particle filter element 7 and the cartridge tube 6. In the example, only a single particle filter element 7 is arranged in the cartridge tube 6. In particular, the respective exhaust gas aftertreatment element 7 is a one-piece, monolithic ceramic body. In another embodiment, two or more exhaust gas aftertreatment elements 7 can be arranged axially one behind the other in the cartridge tube 6. Expediently, identical or similar exhaust gas aftertreatment elements 7 are then used with regard to their exhaust gas aftertreatment function, e.g., two or more particle filter elements 7. Alternatively, two or more exhaust gas aftertreatment elements 7 can also be used that have different exhaust gas aftertreatment functions, e.g.,a particle filter element 7 and a catalyst element. The use of a metallic particle filter element 7 is also conceivable, which can be fixed to the cartridge tube 6, in particular without the use of a bearing mat 8.

[0036] The receiving tube 3 is connected via an annular step 9 to a catalyst tube 10 in which a catalyst element 11 is arranged. In the example shown, the catalyst element 11 is also mounted and axially fixed in the catalyst tube 10 by means of a bearing mat 12. The catalyst element 11 is expediently an oxidation catalyst. With regard to a Fig. 1 and Fig. 2, the catalyst element 11 is preferably arranged upstream of the particle filter element 7 in the exhaust gas flow direction 13 indicated by an arrow.

[0037] The annular step 9 is located on the receiving tube 3 axially opposite an insertion opening 14 of the receiving tube 3. This insertion opening 14 serves to insert the cartridge 5 into the receiving space 4. The annular step 9 is fixedly arranged with respect to the receiving tube 3. In the exemplary embodiments shown here, the annular step 9 is a separate component that is attached to the receiving tube 3 in a suitable manner. In the example, the annular step 9 is also attached to the catalyst tube 10 in a suitable manner. Suitable fastening means include, for example, an axial plug-in connection (shown), preferably in combination with a welded or soldered connection (not shown).

[0038] The insertion opening 14 is arranged within the housing 2 and is axially aligned with and axially spaced from a housing opening 15. The axial direction is defined by a longitudinal center axis 16 of the receiving tube 3, which coincides with a longitudinal center axis 17 of the cartridge 5 when the cartridge 5 is installed. Accordingly, the axial direction runs parallel to the respective longitudinal center axis 16 or 17. This housing opening 15 is dimensioned such that the cartridge 5 can be inserted through the housing opening 15 into the insertion opening 14 and thus into the receiving tube 3 or the receiving space 4. During maintenance, the cartridge 5 can thus be removed from the housing 2 through the housing opening 15. In the installed state or for operation of the exhaust gas aftertreatment device 1, the housing opening 15 is closed with a closure device 18, which is designed such that it can be removed for changing the cartridge 5.This closure device 18 is supported axially on the cartridge 5 and in doing so presses the cartridge 5 in the exhaust gas flow direction 13 into the receiving space 4. The closure device 18 comprises a cover 19 for closing the housing opening 15 and a support ring 20 which is supported axially on the cartridge tube 6. The support ring 20 is designed such that exhaust gas can flow through it radially. In the example, this is achieved in that the support ring 20 is supported on the cartridge tube 6 via a plurality of axially extending webs 21, so that a plurality of openings 22 through which exhaust gas can flow are formed, on the one hand axially between the cartridge tube 6 and the support ring 20 and, on the other hand, in the circumferential direction between adjacent webs 21. A clamp 23 is also provided to fix the cover 19 to the housing 2 and is particularly easy to remove for maintenance purposes.In the clamp connection thus realized, the clamp 23 axially clamps the cover 19 with a . Fig. 2 opening edge designated 24. The support ring 20 is integrated into this clamp connection. To achieve sufficient gas tightness of the closure device 18, Fig. 2 are used. One seal 25 is arranged axially between the opening edge 24 and the support ring 20, while the other seal 26 is arranged axially between the support ring 20 and the cover 19. The clamp 23 engages over the opening edge 24 and the cover 19 and all components arranged axially therebetween, i.e., in this case, the two seals 25, 26 and the support ring 20.

[0039] The exhaust gas aftertreatment device 1 presented here is also characterized by a spring element 27, which is Fig. 3 to 5 for different embodiments. The spring element 27 is supported axially on the one hand on the cartridge tube 6 and on the other hand on the annular step 9. The spring element 27 is in the Fig. 1, so that it creates an axial preload, with which the cartridge 5 is ultimately axially supported on the annular step 9 via the spring element 27. The spring element 27 thereby drives the cartridge 5 in the exhaust gas flow direction 13.

[0040] According to the Fig. 3 to 6, the spring element 27 is designed to be annular and closed all the way around. Furthermore, it is arranged such that it seals an exhaust gas flow path 28, which is also indicated by an arrow and which passes through the particulate filter element 7, from an annular space 29 formed radially between the cartridge tube 6 and the receiving tube 3. The radial direction refers to the respective longitudinal center axis 16, 17. For an improved sealing effect, the spring element 27 rests linearly on the cartridge tube 6 on the one hand and linearly on the annular step 9 on the other.

[0041] In all versions of the Fig. 3 to 6, the spring element 27 has an axially resilient spring region 30 located axially between an end face 31 of the cartridge tube 6 and the annular step 9. The design shown here is preferred, in which the spring region 30 has a wave structure. Several waves curved radially inward and radially outward alternate, which do not touch each other axially, thereby creating the desired axial spring elasticity.

[0042] In all embodiments shown here, the spring element 27 is formed as a single piece or in one piece, so that all sections, contours, and regions of the spring element 27 visible here are integrally formed thereon. In addition to this preferred integral design, a built-up embodiment is also conceivable in which the spring element 27 is assembled from at least two individual parts.

[0043] In the embodiments of the Fig. 3, Fig. 5 and Fig. 6, the spring element 27 has at least one radially outwardly projecting guide contour 32, which is radially supported on the receiving tube 3. This guide contour 32 is expediently designed in a closed, ring-shaped configuration, thereby achieving an additional sealing effect. However, the guide contour 32 primarily serves to radially center the cartridge tube 6 relative to the receiving tube 3 in the receiving space 4.

[0044] At the Fig. 3, the guide contour 32 is arranged radially between the cartridge tube 6 and the receiving tube 3. Furthermore, it is provided here that a support contour 33 adjoins the guide contour 32 on a side facing away from the spring region 30, which support contour 33 is supported radially on the outside of the cartridge tube 6. Furthermore, in this embodiment, a clamping region 34 is formed on the spring element 27, which encompasses the end face 31 of the cartridge tube 6 and thereby fixes the spring element 27 on the cartridge tube 6 by clamping. In the example of Fig. 3, the clamping area 34 is designed as a pocket 35 into which an end section of the cartridge tube 6, which has the end face 31, is axially inserted.

[0045] In the embodiments of the Fig. 5 and Fig. 6, however, the guide contour 32 is arranged axially between the end face 31 and the annular step 9. Here, the guide contour 32 is formed particularly simply with the aid of an outwardly curved shaft of the wave-shaped spring region 30. For this purpose, the first shaft of the wave structure, adjacent to the cartridge tube 6, is expediently extended radially outwardly so far that it comes into radial contact with the receiving tube 3.

[0046] In the Fig. 4 to 6, the spring element 27 has a clip region 36 which is clipped to the cartridge tube 6. For this purpose, the cartridge tube 6 is provided at its end facing the annular step 9 with an inwardly angled collar 37, which in these embodiments forms the end face 31 of the cartridge tube 6. The collar 37 can be angled inward so far that it radially overlaps the particle filter element 7 at the edge. Said collar 37 is now axially clipped into the clip region 36 of the spring element 27, thereby creating a positive-locking fixation of the spring element 27 to the cartridge tube 6. For this purpose, a holding region 38 is formed on the clip region 36, which in this case is S-shaped in longitudinal section and which engages around an inner edge 39 of the collar 37.

[0047] In the Fig. 4 to 6, the clip region 36 also has at least one locking contour 40, which can cooperate in particular with a complementary counter-locking contour 41 formed on the collar 37 in order to radially fix the spring element 27 in the clip region 36 on the collar 37. The locking contour 40 is expediently designed here as a ring-shaped, closed, circumferential, axially projecting projection on the spring element 27. The counter-locking contour 41 is formed as a complementary, ring-shaped, circumferential axial recess on the cartridge tube 6. If the counter-locking contour 41 is missing, the desired linear contact between the spring element 27 and the cartridge tube 6 can be realized with the aid of the locking contour 40, so that the locking contour 40 is then a sealing contour 40 or line contact contour 40 or serves as such.

[0048] In the embodiments of the Fig. 3 to 6, the spring element 27 is supported axially on the annular step 9 via a support area 42. As mentioned, a linear support is preferred here.

[0049] In the embodiments of the Fig.4 to 6, at least one locking contour 43 is also provided in this support area 42, which can expediently interact with a complementary counter-locking contour 44, which is formed for this purpose in the annular step 9. In the example shown, the locking contour 43 is formed by an axially projecting projection on the spring element 27, which expediently runs in a closed manner in the circumferential direction. The counter-locking contour 44 is then formed by a corresponding, annularly closed circumferential axial recess on the annular step 9. Here, the locking contour 43 also effects a radial fixation of the spring element 27 in the support area 42 on the annular step 9. If the counter-locking contour 44 is missing, the desired linear contact between the spring element 27 and the annular step 9 can be realized with the aid of the locking contour 43, so that the locking contour 43 is then a sealing contour 43 or line contact contour 43 or serves as such.

Claims

[1] Exhaust aftertreatment device for an exhaust system of an internal combustion engine, - with a housing (2) in which at least one receiving tube (3) is arranged, which contains a receiving space (4), - with at least one cartridge (5) which is arranged in the receiving space (4) in an exchangeable manner and which has a cartridge tube (6) and at least one exhaust gas aftertreatment element (7) arranged in the cartridge tube (6), - wherein the cartridge tube (6) is supported axially on an annular step (9) at least on one axial end face (31) via at least one spring element (27) under axial prestress, characterized by that the spring element (27) has at least one clamping area (34) which engages around the end face (31) of the cartridge tube (6) and fixes the spring element (27) to the cartridge tube (6) by clamping, or at least one clip area (36) into which an inwardly angled collar (37) of the cartridge tube (6) is axially clipped. [2] Exhaust gas aftertreatment device according to claim 1, characterized by that the spring element (27) is designed in a ring-shaped manner. [3] Exhaust gas aftertreatment device according to claim 2, characterized by that the spring element (27) seals an exhaust gas flow path (28) leading through the exhaust gas aftertreatment element (7) against an annular space (29) which is formed radially between the cartridge tube (6) and the receiving tube (3). [4] Exhaust gas aftertreatment device according to claim 3, characterized by that the spring element (27) lies linearly on the cartridge tube (6) and / or linearly on the annular step (9). [5] Exhaust gas aftertreatment device according to one of claims 1 to 4, characterized by that the spring element (27) has at least one radially outwardly projecting guide contour (32) which is radially supported on the receiving tube (3). [6] Exhaust gas aftertreatment device according to claim 5, characterized by , - that the guide contour (32) is arranged radially between the cartridge tube (6) and the receiving tube (3), or - that the guide contour (32) is arranged axially between the axial end face (31) of the cartridge tube (6) and the annular step (9). [7] Exhaust gas aftertreatment device according to one of claims 1 to 6, characterized by in that, in the event that the spring element (27) has the at least one clip region (36), the clip region (36) has a holding region (38) which engages around an inner edge (39) of the collar (37). [8] Exhaust gas aftertreatment device according to one of the preceding claims, characterized by in that, in the event that the spring element (27) has the at least one clip region (36), the clip region (36) has at least one locking contour (40) which cooperates with a counter-locking contour (41) formed on the collar (37) for positioning the collar (37) on the clip region (36). [9] Exhaust gas aftertreatment device according to one of claims 1 to 8, characterized by that the spring element (27) has at least one axially resilient spring region (30) which extends axially between the end face (31) of the cartridge tube (6) and the annular step (9). [10] Exhaust gas aftertreatment device according to claim 9, characterized by that the spring region (30) has a corrugated structure in longitudinal section. [11] Exhaust gas aftertreatment device according to one of claims 1 to 10, characterized by that the spring element (27) has a support region (42) with which the spring element (27) is supported axially on the annular step (9) and which has at least one locking contour (43) which cooperates with a counter-locking contour (44) formed on the annular step (9) for the radial positioning of the spring element (27) on the annular step (9). [12] Exhaust gas aftertreatment device according to one of claims 1 to 11, characterized by , - that the annular step (9) on the receiving tube (3) is fixedly arranged axially opposite an insertion opening (14) for inserting the cartridge (5) into the receiving space (4), - that the insertion opening (14) is arranged within the housing (2) and axially aligned with a housing opening (15) through which the cartridge (5) can be inserted into the insertion opening (14), - that the housing opening (15) is closed with a closure device (18) which can be removed to change the cartridge (5), which is supported axially on the cartridge (5) and presses the cartridge (5) into the receiving space (4) against the pretension of the spring element (27). [13] Exhaust gas aftertreatment device according to claim 12, characterized by that the closure device (18) has a cover (19) for closing the housing opening (15) and a support ring (20) which is supported axially on the cartridge (5) and through which exhaust gas can flow radially. [14] Cartridge for an exhaust gas aftertreatment device (1) according to one of the preceding claims, - with a cartridge tube (6) for the replaceable insertion of the cartridge (5) into a receiving tube (3) of the exhaust gas aftertreatment device (1), - with at least one exhaust gas aftertreatment element (7) arranged in the cartridge tube (6), - with at least one spring element (27) on the axial end face (31) of the cartridge tube (6) for axially supporting the cartridge tube (6) under axial prestress on the annular step (9) of the exhaust gas aftertreatment device (1) when the cartridge (5) is inserted into the receiving tube (3), - wherein the spring element (27) has at least one clamping region (34) which engages around one end face (31) of the cartridge tube (6) and fixes the spring element (27) to the cartridge tube (6) by clamping, or at least one clip region (36) into which an inwardly angled collar (37) of the cartridge tube (6) is axially clipped.

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