CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to German Patent Application No. 102019133107.2 filed on Dec. 5, 2019. The entire contents of the above-listed application is hereby incorporated by reference for all purposes.

FIELD

The present description relates generally to a fastening device of an exhaust-gas aftertreatment system.

BACKGROUND/SUMMARY

In the field of motor vehicles with internal combustion engines (combustion machines), it is known for components to recirculate exhaust gas to an inlet side of the internal combustion engines, and/or components for purification of the exhaust gas, to be used in an exhaust-gas section of the internal combustion engines.

Owing to more stringent existing and future exhaust-gas regulations, there may be a high demand for installation space for components for exhaust-gas aftertreatment, such as for example exhaust-gas catalytic converter, nitrogen oxide trap (Lean NOx Trap), diesel particle filter or gasoline particle filter and urea injector. For reasons relating to technical process implementation, it is often necessary for the components for exhaust-gas aftertreatment to be arranged in the immediate vicinity of the internal combustion engine. In motor vehicles, with an engine compartment arranged at the front, this demand for installation space competes with the demand for deformation zones for minimizing component degradation in the case of a deformation event. An additional demand for installation space exists in the case of mechanical all-wheel-drive (AWD) power transmission units, which occupy or limit the installation space at the lower rear side of the drivetrain and thus demand for the components for exhaust-gas aftertreatment to be led around these restrictions.

One factor to consider includes the components arranged the engine compartment may be arranged close to one another in order to attain a compact construction. However, this increases the likelihood of oscillations or vibrations being transmitted between the components. This may not be desired due to NVH (noise, vibration, harshness) demands and in particular for vibration-sensitive components such as an exhaust-gas catalytic converter.

As a solution, DE 10 2016 111 301 A1 proposes a device for the suspension of a first component, which may be a component of a drivetrain of a motor vehicle, on a second component, which is spaced apart from said first component and which may be a component of an underbody of the motor vehicle, with a suspension element. In this way, it is possible to provide an elastic suspension for effective vibration decoupling for example of components of the exhaust-gas tract and the underbody of the motor vehicle with relatively low stiffness in a vertical direction of the motor vehicle and with relatively high stiffness in a transverse direction of the motor vehicle, with simultaneously low costs for the suspension.

The suspension element comprises a first bearing section for mounting on the first component and a second bearing section for mounting on the second component. Here, the bearing sections of the suspension elements are connected to one another via a connecting section which is formed at least partially from an elastomer and which is under tensile load in the suspended state. The device is equipped with a stop element which is arranged in the region of the connecting section so as to limit a deflection of at least one section of the connecting section in at least one direction transversely with respect to the longitudinal extent that connects the bearing sections. Such a device ma allow the suspension element and in particular the connecting section thereof to be designed primarily with regard to desired deformability in the longitudinal direction thereof, whereas the possibility of a deformation of the connecting section in at least one direction oriented transversely and perpendicularly with respect to the longitudinal direction is limited by the stop element.

JP 2005 133 546 A proposes a solution for an exhaust-gas structure of an internal combustion engine with turbocharger. In order, in an exhaust-gas channel of the internal combustion engine, to reduce a spacing between an exhaust-gas catalytic converter on the downstream side of the turbocharger and a bulkhead, the internal combustion engine and the transmission are installed vertically in an engine compartment in front of the bulkhead, and the turbocharger is attached, via the exhaust-gas manifold, on one side of the internal combustion engine in a lateral direction. Here, the front end of the exhaust-gas channel, which is arranged between the exhaust-gas catalytic converter and the turbocharger, is connected via a seal ring to an outlet opening of the turbocharger, which outlet opening is directed toward the bulkhead. By absorption of engine vibrations by means of the sealing ring, a spacing of the turbocharger to the exhaust-gas catalytic converter on the downstream side can be reduced.

The competing demands for installation space within the engine compartment demonstrate a constant conflict with the given dimensions of the front end of the motor vehicle and the platform capabilities thereof with regard to free deformation zones. The space for free deformation zones is reduced with every non-deformable component that is added in the vehicle front end. This increases the risk of undesired interventions into the passenger compartment in the case of a frontal deformation event, with the consequence of a considerable increase in a deceleration of vehicle occupants and an increase of the vehicle pulse index (VPI).

JP 5521701 B2 discloses a drive-power-transmitting device specifically for motor vehicles with an internal combustion engine arranged in a vehicle front end and with rear-wheel drive. The drive-power-transmitting device comprises a drive unit which is provided at the front side of a vehicle body in front of a bulkhead and which generates drive power, a differential transmission which is provided at a rear end of the vehicle body, and a power-transmitting shaft for transmitting the drive power of the drive unit to the differential transmission. The drive unit may be in the form of an internal combustion engine with an exhaust-gas device which comprises an exhaust-gas catalytic converter. Between the bulkhead and the rear side of the drive unit, a free space is provided toward the rear, and the exhaust-gas device is arranged in the free space. The power-transmitting shaft is divided into two parts which are connected via a universal joint and which are displaceable relative to one another if a predetermined force in a longitudinal direction is exceeded, for example in the event of a frontal impact. Upon the onset of a frontal impact event, the internal combustion engine and the exhaust-gas catalytic converter can be displaced into the free space, and the two parts of the power-transmitting shaft can be pushed one inside the other.

As an example, JP 2009 241 793 A describes a front part structure of a body of a motor vehicle, with which, even in the case of a relatively large exhaust-gas catalytic converter container, degradation of a bulkhead in the case of a frontal contact event of the motor vehicle can be blocked. The front part structure comprises a subframe, which is provided below a front side frame of the front part structure and to which lower arms of a front wheel suspension apparatus are attached. An engine is held on the subframe and the front side frames. An outlet opening of the engine is provided at the vehicle body front side. The subframes are equipped with right-hand and left-hand longitudinal members which extend in a longitudinal direction of the vehicle body to the left and to the right in front of the engine. A catalytic converter container with a horizontal element for the connection of a vertical element in the direction of the vehicle width is connected to the engine via an exhaust-gas pipe and is formed in an elongate shape in which exhaust-gas pipes are connected to both ends in the longitudinal direction. The catalytic converter container is arranged so as to extend, in the direction of the vehicle width, in the space between the cross member and the engine.

Since the outlet opening of the engine is provided on the surface of the engine at the front side of the vehicle body, the catalytic converter container can be arranged in front of the engine, while at the same time the outlet pipe can be shortened. Thus, because the catalytic converter container is arranged in front of the engine, a contact of the catalytic converter container with the bulkhead can be blocked, even if the engine is pushed rearward in the case of a frontal contact event.

Furthermore, JP 2009029151 A has disclosed a structure for the installation of a drivetrain of a vehicle. The structure comprises a bulkhead arranged between a passenger compartment and an engine compartment, which bulkhead is equipped with a cut-out section which faces toward the rear side of a vehicle body and which serves for covering a tunnel. A drivetrain for driving the rear wheels of the vehicle is arranged partially in the tunnel and the cut-out section. A heat exchanger for cooling the drivetrain, and an exhaust-gas pipe which extends from the drivetrain to the front side of the vehicle body, are arranged in front of the drivetrain. An exhaust-gas aftertreatment unit, which may be in the form of an exhaust-gas catalytic converter, is arranged in front of the heat exchanger in the direction of a width of the vehicle and is equipped with a device which promotes a rearward movement of the exhaust-gas aftertreatment unit in accordance with a mechanical load acting from the front in the event of a frontal vehicle deformation. The device comprises, on both sides of the exhaust-gas aftertreatment unit, rearwardly leading exhaust-gas pipes which are inclined rectilinearly upward at a predetermined angle in their front section and which have a substantially horizontally running rear section, wherein the front and rear sections are connected by a curved section. Upon the onset of a frontal impact event, the exhaust-gas aftertreatment unit together with the front sections of the exhaust-gas pipes are pivoted upward, with the curved sections as centers of rotation, wherein the drivetrain is conveyed further rearward in the cut-out section of the bulkhead.

Furthermore, JP 5381937 B2 describes an exhaust-gas apparatus of a vehicle, which exhaust-gas apparatus is designed such that the discharged exhaust gas is recirculated to the intake side via an exhaust-gas recirculation system (EGR system), wherein, in the direction of the vehicle width, an exhaust-gas purification unit is situated closer than the turbocharger to the outer side. The exhaust-gas recirculation system comprises an EGR cooler, which is arranged between a rear side wall surface of the engine and the exhaust-gas purification unit, an EGR control valve unit, which is arranged at a downstream side of the EGR cooler and which serves for the control of the exhaust-gas recirculation flow rate, a first EGR line for the feed of exhaust gas to the EGR cooler, and a second EGR line for the feed of exhaust gas discharged from the EGR cooler to the EGR control valve unit. A third EGR line is provided in order to discharge the exhaust gas discharged from the control valve unit to the inlet side of the engine. The turbocharger and the exhaust-gas purification unit are arranged adjacent to one another, in the direction of a vehicle width, on that side of the engine which faces toward the vehicle rear side.

The second EGR pipe is installed so as to extend between the turbocharger and the exhaust-gas purification unit to the vehicle rear side. The EGR control valve unit is arranged at a downstream side of the exhaust-gas purification unit, as viewed in the direction from front to rear of the vehicle, in the region of the tunnel section of the bulkhead. Thus, the turbocharger, the exhaust-gas purification unit, the EGR cooling device, the EGR control valve unit etc. can be arranged around the engine in a compact manner without interfering with one another. Furthermore, if an impact load acts in the direction of the rear end at the time of a contact of the vehicle, movement of the EGR control valve unit can be decreased in an effective manner.

One example solution for obtaining a space for deformation zones within the engine compartment despite an increase of a number of non-deformable components for exhaust-gas aftertreatment is an increase in length of the vehicle front end, which would however considerably increase the weight of the motor vehicle, which is not desired.

In view of the above previous examples highlighted, the field of fastening devices for components for the exhaust-gas aftertreatment of an internal combustion engine, which is arranged in particular in an engine compartment of a vehicle front end, still has potential for improvement.

In one example, the issues described above may be addressed by a system for a coupling element coupled to an aftertreatment device in an exhaust gas passage downstream of a turbocharger relative to a direction of exhaust gas flow, wherein the coupling element comprises a rotatable bearing configured to rotate the aftertreatment device relative to the turbocharger in response to a force greater than a threshold force. In this way, a travel path of the aftertreatment device may be altered during a vehicle deformation to decrease an amount of deformation to one or more components.

It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.

