EXHAUST GAS CONDUCTION DEVICE FOR AN INTERNAL COMBUSTION ENGINE

Description

[0001] The invention relates to a device for exhaust gas guidance for an internal combustion engine with an exhaust gas shut-off valve device.

[0002] Adequate and reliable braking of vehicles, especially large commercial vehicles such as trucks or buses, is desirable. While drum or disc brakes are capable of absorbing a large amount of energy over a short period of time, the absorbed energy is converted into heat in the braking mechanism. An engine braking system can be used to assist vehicle braking, particularly as a continuous braking device.

[0003] For example, braking systems are known which have exhaust brakes which block or at least reduce the exhaust gas flow through the exhaust system and thereby increase exhaust gas back pressure to increase engine braking power when the internal combustion engine is idling.

[0004] For example, EP 1 801 392 A2 discloses a device for increasing the braking performance of a multi-cylinder internal combustion engine of a vehicle during engine braking. The device comprises an internal engine braking device, a single- or multi-stage exhaust gas turbocharger with an exhaust turbine and a charge air compressor, and two exhaust manifolds. The exhaust gas emitted from several cylinders can be fed in groups to a turbine inlet via the exhaust manifolds. Each exhaust manifold can be completely shut off by a shut-off valve during engine braking. In a closed position, the shut-off valves rest against an inner wall of the engine braking device.

[0005] Furthermore, EP 3 236 052 A1 discloses an exhaust pressure control valve that allows exhaust gases to be discharged from the entire cross-sectional area of ​​the exhaust line when the exhaust pressure control valve is fully open. For this purpose, an exhaust pressure control valve is mounted on a gas line having a first cross-section into which exhaust gases from the engine flow and arranged upstream or downstream of a muffler.The exhaust pressure control valve comprises: a housing having a first cross-sectional area and a second cross-sectional area larger than the first area and connected to the gas lines to guide the exhaust gas; a valve axis supported along the second cross-section that does not intersect with the first cross-section when viewed from the flow direction, the valve axis being supported by the housing in a direction transverse to the flow direction; and a valve element connected to the valve axis and adjusting the flow of the exhaust gas that communicates with the gas line.

[0006] Similar configurations are also known from DE 10 2017 109062 A1, DE 195 00 475 A1, WO 2017 / 066167 A1 and DE 199 14 213 A1.

[0007] US 2003 / 0234378 A1 discloses an exhaust gas control valve. The exhaust gas control valve comprises a valve housing having at least one inlet, at least one outlet, and a flow channel extending therebetween. A valve seat is adjacent to an opening in the at least one outlet.

[0008] A disadvantage of known solutions can be that the stops and / or sealing surfaces for the butterfly valves have to be integrated into the engine braking devices, which is complex.

[0009] The invention is based on the object of creating an alternative and / or improved device for exhaust gas guidance with an exhaust gas shut-off valve device.

[0010] The object is achieved by the features according to independent claim 1. Advantageous further developments are specified in the dependent claims and the description.

[0011] The invention provides a device for exhaust gas guidance for an internal combustion engine. The device has an exhaust pipe, preferably an exhaust manifold. The device has an exhaust shut-off valve device, namely an exhaust brake valve device, comprising at least one (e.g., two) movable, preferably pivotable, shut-off valves (e.g., brake flaps). The exhaust shut-off valve device is arranged downstream or upstream of the exhaust pipe. In a closed position of the at least one shut-off valve, the at least one shut-off valve rests against at least one stop surface of the exhaust pipe.

[0012] The device can offer the advantage that no stop and / or sealing surface for the butterfly valve needs to be laboriously integrated within the exhaust gas shut-off valve device. Instead, a surface of an upstream or downstream exhaust pipe can simply be used as the stop surface for the butterfly valve. This stop surface on the exhaust pipe can preferably already be present on the exhaust pipe for another purpose, e.g., as a flange surface for flanging the exhaust gas shut-off valve device to the exhaust pipe. This allows a stop surface for the butterfly valve to be functionally integrated into the exhaust pipe, eliminating the need for a separate stop surface.

[0013] The at least one stop surface can expediently form a valve seat for the at least one butterfly valve.

[0014] For example, the at least one shut-off valve can be movably arranged in at least one exhaust duct of the exhaust shut-off valve device. Preferably, the at least one exhaust duct can extend between an inlet opening of the exhaust shut-off valve device and an outlet opening of the exhaust shut-off valve device.

[0015] The exhaust gas shut-off valve device and the exhaust pipe are expediently designed as separate components.

[0016] It is possible that at least one exhaust duct of the exhaust shut-off valve device is in fluid communication with at least one exhaust duct of the exhaust pipe (e.g. directly and / or adjacently).

[0017] In one embodiment, the at least one shut-off valve rests sealingly against the at least one stop surface in the closed position, so that preferably no exhaust gas flows from the exhaust pipe into the exhaust shut-off valve device. The stop surface can thus act as a sealing surface for the shut-off valve. This allows the exhaust gas flow to be completely blocked, for example. This allows high exhaust backpressure and thus high engine braking performance to be achieved.

[0018] In a further embodiment, the at least one shut-off valve partially, completely, and / or annularly overlaps at least one outlet or inlet opening of the exhaust pipe, viewed against a flow direction of the exhaust gas. The overlap can cause the shut-off valve to rest against a surface surrounding the outlet or inlet opening in the closed position, which thus serves as the stop surface for the shut-off valve.

[0019] In a further embodiment, the at least one shut-off valve in the closed position closes at least one outlet opening or inlet opening of the exhaust pipe, preferably completely.

[0020] In one embodiment, the at least one stop surface is annular or ring-segment-shaped. Alternatively or additionally, the at least one stop surface at least partially or completely surrounds and / or delimits at least one outlet or inlet opening of the exhaust pipe. Thus, an already existing boundary of the outlet or inlet opening of the exhaust pipe can expediently be used as the stop surface.

[0021] According to the invention, the at least one stop surface is comprised in a flange surface (e.g., end face) of the exhaust pipe to which the exhaust shut-off valve device is flanged. Thus, the stop surface can be functionally integrated into the existing flange surface.

[0022] According to the invention, the exhaust pipe has two outlet openings or inlet openings and the butterfly valve device has two butterfly valves which are associated with the two outlet openings or inlet openings.

[0023] In a further embodiment, the exhaust gas shut-off valve device further comprises a mounting opening for inserting the at least one shut-off valve into the exhaust gas shut-off valve device and preferably a detachable cover for closing the mounting opening. The mounting opening can simplify installation of the shut-off valve(s), since they do not have to be laboriously inserted through an inlet or outlet opening of the exhaust gas shut-off valve device. The mounting opening can expediently allow pre-assembled or integral units comprising multiple shut-off valves to be inserted together through the mounting opening into the exhaust gas shut-off valve device.

[0024] In a further development, the detachable cover has a web region that partially encompasses a pivot shaft and / or a region between two shut-off valves, for example, preferably to prevent gas transfer between two exhaust ducts of the exhaust shut-off valve device. This enables functional integration into the cover, which can, on the one hand, close the installation opening and, on the other hand, can be used to seal between multiple exhaust ducts in the exhaust shut-off valve device.

[0025] In one embodiment, the at least one shut-off valve has a valve part for creating an exhaust backpressure and / or a bearing area for pivotably supporting the shut-off valve, preferably for connection to a pivot shaft. Alternatively or additionally, the mounting opening is dimensioned such that the at least one shut-off valve can be inserted with the valve part and / or the bearing area and / or that at least two shut-off valves can be inserted together.

[0026] In a further embodiment, the exhaust gas shut-off valve device has at least one exhaust gas duct, which can be conveniently closed by the at least one shut-off valve, and / or the mounting opening is arranged radially with respect to the at least one exhaust gas duct. Thus, the shut-off valves can be inserted radially from the outside through the mounting opening into the exhaust gas duct and mounted there.

[0027] It is also possible for the exhaust gas shut-off valve device to have at least one inlet opening dimensioned such that the at least one shut-off valve, including the valve part and / or the bearing area, can be inserted for installation. Such a design can be advantageously used when the shut-off valves are to be installed individually.

[0028] In one embodiment, the exhaust gas shut-off valve device further comprises a pivot shaft for pivoting the at least one shut-off valve. The pivot shaft can, for example, be manufactured integrally with the at least one shut-off valve as a single unit, and the unit can, for example, be cracked for its assembly. A secure positive fit can be achieved at the separation points during subsequent joining in the exhaust gas shut-off valve device. The cracked individual parts can be inserted more easily into the exhaust duct and / or a corresponding assembly opening can be dimensioned smaller.

[0029] In a further development, the pivot shaft is formed as a hollow shaft, and individual parts of the cracked unit can be joined together by a screw inserted into the hollow shaft. This allows, for example, the cracked individual parts to be easily joined once they have been positioned in the exhaust valve device.

[0030] The hollow shaft can expediently have an internal thread at least in a bearing area of ​​an outer butterfly valve or in an outer shaft section, into which the screw for joining the cracked individual parts can be screwed. Alternatively, a nut could also be used for joining.

[0031] In a further embodiment, the unit is cracked at one or more predetermined separation points, preferably in or (e.g., on one or both sides) on a bearing area of ​​the at least one butterfly valve. This can simplify, for example, the insertion of the butterfly valves into the exhaust gas butterfly valve device during assembly and the joining of the cracked individual parts.

[0032] In one embodiment, the exhaust gas shut-off valve device has a multi-part pivot shaft designed as a hollow shaft, the individual parts of which can preferably be connected to one another by a screw that can be inserted into the hollow shaft.

[0033] In a further development, the at least one butterfly valve has a bearing area, which expediently forms a hollow shaft section of the pivot shaft. It is possible for the bearing area to be connected in a rotationally fixed manner to at least one further hollow shaft section of the pivot shaft, preferably by means of a positive connection (e.g., a pin connection or a multi-tooth connection).

[0034] For example, the positive locking can be provided on mutually facing bottom or base surfaces of the bearing area and the further hollow shaft section. The bottom or base surfaces can be aligned in a plane perpendicular to a longitudinal axis of the pivot shaft.

[0035] The exhaust gas shut-off valve device can expediently be arranged upstream of an exhaust gas turbine of a turbocharger, e.g. directly upstream thereof.

[0036] Preferably, the exhaust valve device can be mounted on the exhaust pipe, e.g., detachably by means of one or more screws, which expediently press flange surfaces of the exhaust pipe and the exhaust valve device together.

[0037] The exhaust gas shut-off valve device can expediently be designed to increase the engine braking power of the internal combustion engine, preferably by partially or completely closing one or more exhaust gas ducts in a closed position of the at least one shut-off valve.

[0038] In a further exemplary embodiment, the at least one shut-off flap is positioned, in an open position, partially outside the exhaust shut-off flap device and / or within an exhaust duct of a turbocharger housing arranged downstream of the shut-off flap device. This enables a compact exemplary embodiment. For example, the at least one shut-off flap, preferably a flap part of the at least one shut-off flap, can extend, in an open position, partially into an inlet region of an exhaust duct of a turbocharger housing arranged downstream of the exhaust shut-off flap device. It is additionally possible for a clearance or recess for the at least one shut-off flap to be expediently arranged on a peripheral wall of the inlet region.

[0039] The invention also relates to a motor vehicle, preferably a commercial vehicle (e.g. truck or bus), with a device as disclosed herein.

[0040] It is also possible to use the device as disclosed herein for passenger cars, large engines, off-road vehicles, stationary engines, marine engines, etc.

[0041] The above-described preferred embodiments and features of the invention can be combined with one another as desired. Further details and advantages of the invention are described below with reference to the accompanying drawings. They show: Figure 1 shows a sectional view of an exemplary exhaust gas routing device for an internal combustion engine according to the present disclosure; Figure 2 shows a further sectional view of the exemplary exhaust gas routing device; Figure 3 shows a perspective view of the exemplary exhaust gas routing device; Figure 4 shows a perspective view of an exemplary butterfly valve device of the exhaust gas routing device; Figure 5 shows a sectional view of the exemplary butterfly valve device; Figure 6 shows a perspective assembly drawing of the exemplary butterfly valve device; Figure 7 shows a perspective assembly drawing of an exemplary pivot shaft and two exemplary butterfly valves of the butterfly valve device; Figure 8 shows a perspective view of a further exemplary pivot shaft and two further exemplary butterfly valves of the butterfly valve device; Figure 9 shows a sectional assembly drawing of a further exemplary butterfly valve device;and Figure 10 shows a further sectional view of the exemplary device for exhaust gas guidance. ;

[0042] The embodiments shown in the figures correspond at least partially, so that similar or identical parts are provided with the same reference numerals and for their explanation reference is also made to the description of the other embodiments or figures in order to avoid repetition.

[0043] The Figures 1 to 3 show a device 10 for exhaust gas routing for an internal combustion engine. The internal combustion engine can be incorporated, for example, in a motor vehicle, preferably a commercial vehicle (for example, a truck or bus), for driving the motor vehicle. During operation of the internal combustion engine, the device 10 can adjust or increase an exhaust backpressure to effect (internal) engine braking, for example, on downhill gradients. This allows for greater engine braking performance to be achieved.

[0044] The exemplary device 10 is described below with reference to the Figures 1 to 5 described.

[0045] The device 10 comprises an exhaust pipe 12 and an exhaust shut-off valve device 14, preferably an exhaust brake valve device. The exhaust shut-off valve device 14 is flanged to the exhaust pipe 12.

[0046] The exhaust pipe 12 has at least one inlet opening and at least one outlet opening 16, which are at least partially connected to one another by one or more internal channels for conducting exhaust gas. As illustrated, the exhaust pipe 12 can be dual-flow, e.g., with a dual-flow exhaust manifold and a dual-flow exhaust manifold. The dual-flow exhaust manifold can be attached to a multi-cylinder cylinder head or multiple single-cylinder cylinder heads to receive exhaust gas in groups from multiple cylinders of the internal combustion engine in two separate exhaust gas channels. As illustrated, for example, a first exhaust gas channel can receive exhaust gas from multiple cylinders of an internal combustion engine, and a second exhaust gas channel can receive exhaust gas from multiple additional cylinders of an internal combustion engine. The dual-flow exhaust manifold can, for example, have two outlet openings 16 for discharging exhaust gas from the dual-flow exhaust manifold.

[0047] It is possible for the exhaust pipe 12 to be designed differently than shown. For example, the exhaust pipe 12 may be single-flow and / or may not have a collection area and / or may not have a bend area. For example, the exhaust pipe 12 may also be designed as a simple pipe section.

[0048] It is also possible for the exhaust pipe 12 to be arranged at a different position, for example not directly downstream of the cylinders of the internal combustion engine, for example downstream of an exhaust turbine of a turbocharger of the internal combustion engine, in a bypass of a turbine of a turbocharger of the internal combustion engine, as an outlet pipe (e.g. diffuser) of an exhaust turbine of a turbocharger or as an inlet pipe of an exhaust turbine of a turbocharger of the internal combustion engine.

[0049] The exhaust shut-off valve device 14 is arranged downstream of the exhaust pipe 12. The exhaust shut-off valve device 14 can expediently be arranged directly upstream of an exhaust turbine of a turbocharger. It is also possible, for example, for the exhaust shut-off valve device 14 to be arranged, for example, in a bypass of the exhaust turbine or downstream of the exhaust turbine. However, it may also be possible for the exhaust shut-off valve device 14 to be arranged upstream of the exhaust pipe 12.

[0050] The exhaust gas shut-off valve device 14 has an exhaust gas guide part 18 and an actuating part 20. The actuating part 20 serves to actuate one or more shut-off valves 22, preferably brake flaps, in the exhaust gas guide part 18. The shut-off valves 22 can each have a flap part 22A for creating an exhaust gas backpressure and a bearing area 22B for preferably pivotably supporting the shut-off valves 22.

[0051] In the illustrated embodiment, the exhaust gas guide part 18 is designed as a dual-flow system with two (exhaust gas) inlet openings 24, two shut-off valves 22, two exhaust gas ducts 26, and two outlet openings 28, for example, for supplying exhaust gas to a dual-flow exhaust turbine (not shown) of a turbocharger of the internal combustion engine. However, it is also possible, for example, for the exhaust gas guide part 18 to be designed as a single-flow system, with only one (exhaust gas) inlet opening 24, one shut-off valve 22, one exhaust gas duct 26, and one outlet opening 28.

[0052] The inlet openings 24 of the exhaust gas guide part 18 are opposite the outlet openings 16 of the exhaust pipe 12. The exhaust gas ducts 26 each extend between one of the inlet openings 24 and one of the outlet openings 28. One of the shut-off valves 22 is pivotally arranged in each of the exhaust gas ducts 26 for blocking, partially blocking, or opening the exhaust gas ducts 26 or the inlet openings 24. It is also possible that no pivoting mechanism is provided for pivoting the shut-off valve 22, but rather another movement mechanism for moving the shut-off valve 22, for example, a translational movement mechanism.

[0053] The exhaust guide part 18 is mounted, preferably flanged, on the exhaust pipe 12. For example, a plurality of screws may be provided to fasten the exhaust guide part 18 and the exhaust pipe 12 together. The exhaust pipe 12 and the exhaust guide part 18 contact each other at their respective flange surfaces 30 and 32. The flange surface 30 of the exhaust pipe 12 surrounds and defines the outlet openings 16. The flange surface 32 of the exhaust guide part 18 surrounds and defines the inlet openings 24. The flange surfaces 30, 32 may have aligned screw holes to fasten the exhaust guide part 18 and the exhaust pipe 12 together.

[0054] The exhaust pipe 12 and the exhaust guide part 18 are adapted to one another such that the flange surface 30 of the exhaust pipe 12 serves as a stop surface for the shut-off valves 22 in their closed position. In the closed position, the shut-off valves 22 are pressed against the flange surface 30 by the actuating part 20, so that the outlet openings 16 are closed by the shut-off valves 22. The shut-off valves 22 preferably lie flush against the flange surface 30, thus also providing a sealing effect and essentially preventing exhaust gas from flowing into the exhaust ducts 26 of the exhaust guide part 18. Therefore, separate stops or sealing surfaces for the shut-off valves 22 in the exhaust guide part 18 can be dispensed with.

[0055] Specifically, the flange surface 30 can have two stop surfaces 34 for the two butterfly valves 22. The stop surfaces 34 can each surround and delimit one of the outlet openings 16 in a ring shape. The stop surfaces 34 can, for example, have a ring width of several millimeters. In other words, the butterfly valves 22 can each extend several millimeters beyond the respective outlet opening 16, i.e., the outlet openings can overlap by several millimeters. A flap contour of the butterfly valves 22 is designed such that, when installed, it achieves an overlap of several millimeters with respect to the outlet opening 16 and a sealing surface can be created.

[0056] For clarity, the flange surface 30 and the outlet openings 16 are in Figure 5shown in dashed lines with respect to the flange surface 32 of the exhaust guide part 18. The stop surfaces 34 are located between the outer circumference of the butterfly valves 22 and the inner circumference of the inlet openings 24, but on the side of the exhaust pipe 12 (not in Figure 5 shown). In the closed position, the butterfly valves 22 are pressed against the stop surfaces 34 by the actuating part 20.

[0057] The shut-off valves 22 are movable, preferably pivotable, between the closed position and an open position. In the closed position, the shut-off valves 22 can seal the outlet opening 16 of the exhaust pipe 12. No exhaust gas flows through the exhaust ducts 26. The closed position is, for example, Figures 1 and 2 shown.

[0058] In the open position, the butterfly valves 22 can release (open) the outlet opening 16 of the exhaust pipe 12. Exhaust gas can flow into the exhaust ducts 26 and be directed, for example, to an exhaust turbine. Figure 2 The opening position is represented by a hatched butterfly valve.

[0059] In intermediate positions between the open position and the closed position, a reduced exhaust gas flow can flow through the partially opened butterfly valves 22 into the exhaust gas ducts 26 and be directed, for example, to an exhaust gas turbine.

[0060] In embodiments in which the exhaust pipe is arranged downstream of the exhaust guide part, at least one shut-off flap can close at least one inlet opening of the exhaust pipe in the closed position, so that preferably no exhaust gas flows from the exhaust guide part into the exhaust pipe. Analogous to the embodiment described above, the at least one shut-off flap can partially or completely overlap the inlet opening (viewed in a flow direction of the exhaust gas), the stop surface can surround or delimit the inlet opening, preferably in an annular or ring-segment shape, etc.

[0061] The movement of the butterfly valves 22 is effected by the actuating part 20. The actuating part 20 can, for example, be a compressed air cylinder 36 (see Figures 3 to 5 ) to actuate the butterfly valve 22. A translational movement of the pneumatic cylinder 36 can be achieved, for example, via a linkage 38 (only partially in Figure 5 shown) to a pivot shaft 40 for rotating the pivot shaft 40. The linkage 38 may, for example, comprise a first rod and a second rod that are articulated, preferably pivotally connected to one another. The first rod may be attached to a movable piston of the pneumatic cylinder 36. The second rod may be attached to the pivot shaft 40.

[0062] The pivot shaft 40 can be connected to the butterfly valves 22 in a rotationally fixed manner, for example by a positive fit. For example, the pivot shaft 40 can be connected by means of a key, as shown in the Figures 1 and 2As shown, the actuating part 20 can be connected to the shut-off valves 22 in a rotationally fixed manner. The shut-off valves 22 can be opened or closed by rotating the pivot shaft 40. Alternatively, the actuating part 20 can comprise, for example, a hydraulic cylinder or an electric motor, for example an electric servomotor, for rotating the pivot shaft 40.

[0063] It is possible that a spring assembly 42 (see Figure 5) or another elastic element is provided to press the pivot shaft 40 against the bearing (e.g., plain bearing) for the pivot shaft 40 within the exhaust gas guide part 18. This can expediently prevent exhaust gas leakage and ensure tightness. To enable preloading of the spring assembly 42, a counterholder 44, for example, can be arranged at a distance from the second rod of the linkage 38. The spring assembly 42 can, for example, press against the second rod of the linkage 38 and thus against the pivot shaft 40 attached thereto.

[0064] As in the Figures 3 to 6 As shown by way of example, a screw plug 46 can be arranged on a side of the exhaust gas guide part 18 opposite the actuating part 20 in order to close a bore for arranging a bearing (e.g. plain bearing) for the pivot shaft 40, preferably in a gas-tight manner.

[0065] As in the Figures 1 to 6As shown, the exhaust gas guide part 18 can have a cover 48. The cover 48 can releasably close a mounting opening 50 of the exhaust gas guide part 18. The shut-off valves 22 can be inserted into the exhaust gas guide part 18 through the mounting opening 50 and positioned in the exhaust gas ducts 26. After the shut-off valves 22 have been installed, the mounting opening 50 can be closed by the cover 48. For example, removable screws can be used to fasten the cover 48, as shown.

[0066] The mounting opening 50 can be arranged radially with respect to a path of the exhaust ducts 26. The mounting opening 50 is dimensioned such that the butterfly valves 22, including the bearing areas 22B and the valve parts 22A, can be passed completely through it. The arrangement of the cover 48 and the mounting opening 50 can simplify the assembly of the butterfly valves 22, particularly in a case where several butterfly valves 22 are to be assembled together as a joined or integral unit.

[0067] The cover 48 may have a web area 52 (see Figures 1, 2 and 6). The web region 52 can partially encompass a cylindrical region between the bearing regions 22B of the butterfly valves 22 with a small gap. The web region 52 can, for example, have a surface in the shape of a circular cylinder shell segment for encompassing the cylindrical region. The surface in the shape of a circular cylinder shell segment can face the butterfly valves 22. The gap (e.g., approximately ≤ 1 to 2 mm, preferably ≤ 0.5 mm) can be selected such that gas transfer between the exhaust channels 26 in the exhaust guide part 18 is substantially prevented.

[0068] Alternatively or in addition to the cover 48 and the assembly opening 50, it is also possible, for example, for the shut-off valves 22 to be inserted individually through the inlet openings 24 (see Figure 9 ). If threading is carried out through the inlet openings 24, it is not necessary to provide the mounting opening 50 and the cover 48.

[0069] The Figure 7 and the Figure 8 show further embodiments for connecting the pivot shaft 40 and the butterfly valves 22.

[0070] In Figure 7 It is shown that the butterfly valves 22 are designed as individual parts. The butterfly valves 22, preferably the bearing areas 22B of the butterfly valves 22, can be connected to several shaft pieces or shaft sections 54 of the pivot shaft 40 in a rotationally fixed and form-fitting manner, e.g., by means of a pin connection or a multi-tooth connection. The pivot shaft 40 can be designed as a hollow shaft, so that the shaft sections 54 and the bearing areas 22B, which are also designed as hollow shaft sections, can be connected to one another by means of a screw 56 after the butterfly valves 22 have been positioned in the exhaust ducts. For example, the screw 56 can be screwed into an internal thread in the outermost shaft section 54.

[0071] In Figure 8It is shown that the pivot shaft 40 and the butterfly valve(s) 22 can be manufactured as a single, integral unit (e.g., by means of primary forming such as casting, forging, or printing). The unit can then be cracked at predetermined separation points 58 to enable assembly in the exhaust gas guide part 18, e.g., via the inlet openings 24. The separation points for cracking can, for example, be arranged on one side or both sides of the bearing areas 22B of the butterfly valves 22. After insertion into the exhaust gas ducts 26, the cracked butterfly valves 22 can then be reassembled in a form-fitting manner. For example, the pivot shaft 40 can be formed as a hollow shaft, and the individual parts of the cracked unit can be joined together by a screw 56 that can be inserted into the hollow shaft. For example, the screw 56 can be screwed into an internal thread in the bearing area 22B of the outer butterfly valve 22.

[0072] Figure 10shows a further, particularly compact embodiment. Here, the shut-off valve device 14 and a turbocharger housing 60 arranged downstream thereof are designed such that the shut-off valve 22, preferably the valve part 22A, extends partially into an inlet region 62 of an exhaust duct 64 of the turbocharger housing 60 in an open position. As shown, a clearance or recess 66 for the shut-off valve 22 can expediently be arranged on a peripheral wall of the inlet region 62.

[0073] Thus, the overall height of the butterfly valve device 14 can be significantly reduced compared to a solution in which the butterfly valve 22 is positioned completely in the butterfly valve device 14 in the open position (indicated in Figure 10 with a dashed line).

[0074] The invention is not limited to the preferred embodiments described above. Rather, a multitude of variants and modifications are possible which fall within the claimed scope of protection. In particular, the individual features of independent claim 1 are each disclosed independently of one another. In addition, the features of the subclaims are also disclosed independently of all features of independent claim 1 and, for example, independently of the features relating to the presence and / or configuration of the exhaust pipe and / or the exhaust shut-off valve device of independent claim 1. All ranges stated herein are to be understood as being disclosed in such a way that, as it were, all values ​​falling within the respective range are individually disclosed, e.g., also as respectively preferred, narrower outer limits of the respective range. List of reference symbols

[0075] 10 Exhaust gas routing device 12 Exhaust pipe 14 Exhaust shut-off valve device 16 Outlet opening 18 Exhaust gas routing part 20 Actuating part 22 Shut-off valve 22A Flap part 22B Bearing area 24 Inlet opening 26 Exhaust duct 28 Outlet opening 30 Flange surface 32 Flange surface 34 Stop surface 36 Pneumatic cylinder 38 Linkage 40 Pivot shaft 42 Spring assembly 44 Counterholder 46 Screw plug 48 Cover 50 Mounting opening 52 Web area 54 Shaft section 56 Screw 58 Separation point for cracking 60 Turbocharger housing 62 Inlet area 64 Exhaust duct 66 Recess

Claims

1. A device (10) for conducting exhaust gas for an internal combustion engine, comprising: an exhaust pipe (12); and an exhaust shut-off flap device (14) comprising at least one movable, preferably pivotable, shut-off flap (22), wherein the exhaust shut-off flap device (14) is arranged downstream or upstream of the exhaust pipe (12) and the at least one shut-off flap (22) rests against at least one abutment surface (34) of the exhaust pipe (12) in a closed position of the at least one shut-off flap (22); wherein the exhaust pipe (12) comprises two outlet openings (16) or inlet openings; wherein the exhaust shut-off flap device (14) is an exhaust brake flap device; and wherein the shut-off flap device (14) comprises two shut-off flaps (22) associated with the two outlet openings (16) or inlet openings characterised in that the at least one abutment surface (34) is comprised in a flange surface (30) of the exhaust pipe (12) to which the exhaust shut-off flap device (14) is flange-mounted.

2. The device (10) according to claim 1, wherein: the at least one shut-off flap (22) rests sealingly against the at least one abutment surface (34) in the closed position, so that preferably no exhaust gas flows from the exhaust pipe (12) into the exhaust shut-off flap device (14).

3. The device (10) according to claim 1 or claim 2, wherein: viewed in or against a flow direction of the exhaust gas, the at least one shut-off flap (22) partially, completely, and / or annularly overlaps the at least one outlet opening (16) or inlet opening of the exhaust pipe (12); and / or the at least one shut-off flap (22) closes, preferably completely, the at least one outlet opening (16) or inlet opening of the exhaust pipe (12) in the closed position.

4. The device (10) according to one of the preceding claims, wherein: the at least one abutment surface (34) is annular or annular segment-shaped; and / or the at least one abutment surface (34) at least partially or completely surrounds and / or limits at least one outlet opening (16) or inlet opening of the exhaust pipe (12).

5. The device (10) according to any one of the preceding claims, wherein the exhaust shut-off flap device (14) further comprises a mounting opening (50) for inserting the at least one shut-off flap (22) into the exhaust shut-off flap device (14); and a detachable cover (48) for closing the mounting opening (50).

6. The device (10) according to claim 5, wherein: the detachable cover (48) comprises a web region (52) which partially embraces a pivot shaft (40) and / or a region between two shut-off flaps (22), preferably for preventing a gas transfer between two exhaust ducts (26) of the exhaust shut-off flap device (14).

7. The device (10) according to claim 5 or claim 6, wherein: the at least one shut-off flap (22) comprises a flap portion (22A) for effecting an exhaust gas back pressure and a bearing region (22B) for pivotably bearing the shut-off flap (22), preferably for connection to a pivot shaft (40); and the mounting opening (50) is dimensioned such that the at least one shut-off flap (22) can be inserted with the flap portion (22A) and the bearing region (22B) and / or that at least two shut-off flaps (22) can be inserted together.

8. The device (10) according to any one of claims 5 to 7, wherein: the exhaust shut-off flap device (14) comprises at least one exhaust duct (26), which can be closed by the at least one shut-off flap (22); and the mounting opening (50) is arranged radially with respect to the at least one exhaust duct (26).

9. The device (10) according to one of the previous claims, wherein: the exhaust shut-off flap device (14) further comprises a pivot shaft (40) for pivoting the at least one shut-off flap (22); the pivot shaft (40) is integrally manufactured as a single unit with the at least one shut-off flap (22); and the unit is cracked for its assembly, preferably at one or more predetermined separation points (58) in or on a bearing region (22B) of the at least one shut-off flap (22).

10. The device (10) according to claim 9, wherein: the pivot shaft (40) is formed as a hollow shaft, and individual parts of the cracked unit can be joined together by a screw (56), which can be inserted into the hollow shaft.

11. The device (10) according to one of claims 1 to 8, wherein: the exhaust shut-off flap device (14) comprises a multi-part pivot shaft (40) formed as a hollow shaft, the individual parts of which can be connected to one another by a screw (56) that can be inserted into the hollow shaft.

12. The device (10) according to any one of claims 9 to 11, wherein: the at least one shut-off flap (22) comprises a bearing region (22B) forming a hollow shaft portion of the pivot shaft (40); and the bearing region (22B) is non-rotatably connected to at least one further hollow shaft section (54) of the pivot shaft (40), preferably by form-fit.

13. The device (10) according to one of the preceding claims, wherein: the at least one shut-off flap (22) is positioned in an opening position partially outside the exhaust shut-off flap device (14) and / or inside an exhaust duct (64) of a turbocharger housing (60) arranged downstream of the exhaust shut-off flap device (14).

14. Motor vehicle, preferably a commercial vehicle, with a device (10) according to one of the preceding claims.