Motor vehicle with an internal combustion engine and with an exhaust system, as well as an exhaust system for a motor vehicle

Abstract

The invention relates to a motor vehicle (K) with an internal combustion engine (100) and with an exhaust system (10), which - is designed to discharge exhaust gas (12) emitted by the internal combustion engine (100) into an environment (U) of the motor vehicle (K), - has a suction body (40) designed to at least partially absorb at least a quantity (50) of liquid formed in and / or penetrating the exhaust system (10) and - has a pressure device (60) by means of which the suction body (40) can be compressed at least in certain areas in order to push out the amount of liquid (50) absorbed by the suction body (40) from the suction body (40). Another aspect of the invention relates to an exhaust system (10) for a motor vehicle (K).

Description

[0001] The invention relates to a motor vehicle with an internal combustion engine and an exhaust system designed to discharge exhaust gas emitted by the internal combustion engine into the environment of the motor vehicle. A further aspect of the invention relates to an exhaust system for such a motor vehicle.

[0002] When a motor vehicle's internal combustion engine is operated, i.e., when fuel is burned to drive various shafts, such as the engine's crankshaft, transmission shafts, and finally the vehicle's drive wheels that transmit torque, exhaust gas is produced. Ideally, this exhaust gas contains carbon dioxide and water as its constituents. After passing through appropriate exhaust aftertreatment devices connected to the engine, the exhaust gas is discharged into the vehicle's environment via the vehicle's exhaust system.At low ambient temperatures and with frequent short trips, certain exhaust system components, especially those furthest from the engine near the exhaust pipe (e.g., in the muffler), may remain cold enough despite the flow of hot exhaust gases for condensation, primarily water, to form. This condensation can then splash onto sensors within the exhaust system due to the vehicle's dynamic movements, potentially damaging them.

[0003] The object of the present invention is to provide a motor vehicle and an exhaust system of the type mentioned at the outset, in which liquid formed in the exhaust system or entering the exhaust system from the environment of the motor vehicle can be discharged from the exhaust system in an improved manner.

[0004] This problem is solved by a motor vehicle with the features of claim 1 and by an exhaust system with the features of claim 9. Advantageous embodiments with expedient further developments of the invention are specified in the dependent claims.

[0005] A first aspect of the invention relates to a motor vehicle with an internal combustion engine and an exhaust system. The exhaust system is designed to discharge exhaust gas emitted by the internal combustion engine into the surrounding environment of the motor vehicle. Furthermore, the exhaust system includes a suction element designed to at least partially absorb at least a certain quantity of liquid formed in and / or entering the exhaust system. In addition, the exhaust system includes a pressure device by means of which the suction element can be compressed, at least in certain areas, in order to force the quantity of liquid absorbed by the suction element out of the suction element.

[0006] The invention is based on the understanding that absorbing the liquid is advantageous because at least a portion of the liquid remains stored in the suction body and therefore cannot participate in any sloshing movements caused by vehicle dynamics. In other words, only the portion of the liquid that is not absorbed can slosh around within the exhaust system. This reduces the likelihood of liquid-related damage to sensors located in or protruding into the exhaust system's interior. Furthermore, it is advantageous that, under favorable operating conditions, particularly when the exhaust system is at operating temperature, the pressure device allows the liquid stored in the suction body to be selectively forced out by compression, i.e., by applying pressure to the suction body.When the engine is at operating temperature, the exhaust system can reach a temperature, particularly the wall temperature, above the boiling point of water at its coldest point. This allows the previously absorbed liquid to transition from its liquid phase to the gaseous phase and thus be released into the environment as a gas along with the exhaust gas produced during the operation of the internal combustion engine via the exhaust system's tailpipe. Therefore, when the engine is at operating temperature, a portion of the absorbed liquid can evaporate due to the sufficiently high temperature and escape from the intake manifold.In order to achieve a particularly effective removal of the fluid from the exhaust system when the system is at operating temperature, i.e., to remove as large a proportion or even the entire fluid volume from the suction body, the latter can be compressed by means of the pressure device, so that the fluid volume is at least partially forced out of the suction body and, under the influence of the high temperature, can change at least almost completely from the liquid phase to the gas phase, for example at the wall of the exhaust system, which facilitates its exit from the exhaust system via the exhaust pipe.

[0007] In an advantageous embodiment of the invention, the absorbent body is designed as a sponge. This is advantageous because the sponge-shaped absorbent body can, on the one hand, store particularly large quantities of liquid and, on the other hand, can be compressed easily and without damage.

[0008] In a further advantageous embodiment of the invention, the pressure device is configured to compress the suction element depending on the exhaust gas temperature. This is advantageous because it enables particularly demand-oriented compression of the suction element. The higher the exhaust gas temperature, the more the suction element can be compressed, i.e., squeezed together by the pressure device.

[0009] In a further advantageous embodiment of the invention, the pressure device for temperature-dependent compression of the suction element comprises a bimetallic arrangement. This is advantageous because the bimetallic arrangement is particularly robust and can therefore be operated with a high degree of reliability. The bimetallic arrangement can comprise two interconnected metal strips or plates made of different metals, which expand differently under the influence of the temperature at the wall of the exhaust system and / or under the influence of the exhaust gas temperature. This temperature-induced expansion results in a reversible deformation of the bimetallic arrangement, whereby the bimetallic arrangement transitions from an undeformed state to a deformed state. In its undeformed state, the bimetallic arrangement can bear against the suction element.During the reversible transition from the undeformed state to the deformed state, the bimetallic arrangement can compress the suction body, causing liquid to escape from the suction body and be exposed to the high temperature (wall temperature) and / or exhaust gas temperature, which promotes the phase change of the liquid from the liquid phase to the gas phase and ultimately the removal of the liquid from the exhaust system.

[0010] In a further advantageous embodiment of the invention, the pressure device for temperature-dependent compression of the suction body incorporates an expansion element. This is advantageous because such an expansion element, which may, for example, contain wax, can be arranged in a particularly space-saving manner within the exhaust system. Furthermore, the expansion element can be operated with exceptional reliability. An expansion element represents an actuator filled with expansion material and can, for example, consist of a piston housing, a working piston movably mounted within the piston housing, and the expansion material itself.Due to the influence of temperature (for example, the wall temperature of the exhaust system) and / or the exhaust gas temperature, the expansion element can reversibly, i.e., non-destructively, transition from an undeformed state, in which the working piston is retracted, to a deformed state, in which the working piston is at least partially extended from the piston housing. In the undeformed state, the working piston of the expansion element can rest against the suction body. As a result of the influence of temperature or exhaust gas temperature, the expansion element can transition from the undeformed state to the deformed state, thereby compressing the suction body. This allows fluid to escape from the suction body and be exposed to the high temperature (wall temperature) and / or exhaust gas temperature, which facilitates the phase change of the fluid from the liquid phase to the gas phase and ultimately the removal of the fluid from the exhaust system.

[0011] In a further advantageous embodiment of the invention, the pressure device for temperature-dependent compression of the suction body incorporates a spring element. This is advantageous because the spring element can be operated with particularly high reliability and has a simple design. The spring element can, for example, be designed as a leaf spring or a coil spring. Due to the influence of temperature (for example, the wall temperature of the exhaust system) and / or exhaust gas temperature, the spring element can reversibly, i.e., non-destructively, transition from an undeformed state, in which the spring element is retracted, to a deformed state, in which the spring element is extended. In the undeformed state, the spring element can rest against the suction body. As a result of the influence of temperature or exhaust gas temperature, the spring element can then be compressed.Exhaust gas temperature can cause the spring element to transition from the undeformed state to the deformed state, thereby compressing the suction body, i.e., squeezing it together, which allows fluid to escape from the suction body and be exposed to the high temperature (wall temperature) and / or exhaust gas temperature, thus promoting the phase change of the fluid from the liquid phase to the gas phase and ultimately the removal of the fluid from the exhaust system.

[0012] In a further advantageous embodiment of the invention, the pressure device for temperature-dependent compression of the suction body comprises an electric motor and / or a mechanical cylinder. This is advantageous because the use of both the electric motor and the mechanical cylinder enables particularly strong compression of the suction body, allowing the liquid to be forced out of the suction body over a particularly large area. The electric motor can, for example, be designed as a linear motor and actuate a push rod by means of which the compression of the suction body can be effected. The mechanical cylinder can accommodate an extendable piston by means of which the suction body can be compressed.

[0013] In a further advantageous embodiment of the invention, the suction element is arranged in the lowest geodetic region of the exhaust system's interior. This is advantageous because it enables particularly effective suction of the fluid contained in the exhaust system. By arranging it in the lowest geodetic region of the exhaust system's interior, the fluid can flow to the suction element by gravity.

[0014] A second aspect of the invention relates to an exhaust system for a motor vehicle according to the first aspect of the invention. This allows liquid formed in the exhaust system or entering the exhaust system from the environment of the motor vehicle to be discharged from the exhaust system in an improved manner.

[0015] The preferred embodiments and their advantages presented with respect to one of the aspects apply accordingly to the other aspects of the invention and vice versa.

[0016] The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the figure description and / or shown in the figures alone, can be used not only in the combination specified in each case, but also in other combinations or on their own, without leaving the scope of the invention.

[0017] Further advantages, features and details of the invention will become apparent from the claims, the following description of preferred embodiments and the drawings.

[0018] The invention is explained below again using a specific embodiment. This is illustrated by: Fig. 1 a schematic sectional view of a section of a first variant of an exhaust system of a highly abstracted motor vehicle, which is designed to discharge exhaust gas from an internal combustion engine of the motor vehicle to an environment of the motor vehicle; Fig. 2. A schematic sectional view of a section of a second variant of the exhaust system; and Fig. 3 a schematic sectional view of a section of a third variant of the exhaust system.

[0019] The characteristics described below concerning one variant (first variant, second variant) of an exhaust system 10, third variant) also apply to the other variants, unless otherwise described.

[0020] Fig. Figure 1 shows, in an abstract representation, a motor vehicle K with an internal combustion engine 100 and with the first variant of the exhaust system 10, shown in a schematic sectional view, of which a partial section is visible. During operation of the internal combustion engine 100, exhaust gas 12 is emitted, which in Fig. 1 is abstracted by an arrow, with the arrowhead of the arrow indicating a flow direction of the exhaust gas 12.

[0021] The exhaust system 10 is designed to discharge the exhaust gas 12 emitted by the internal combustion engine 100 to an environment U of the motor vehicle K. The exhaust system 10 has a suction element 40 which is designed to at least partially absorb a quantity 50 of liquid formed in the exhaust system 10 and liquid that additionally or alternatively enters the exhaust system 10.

[0022] The liquid quantity 50, in the form of water, which can form when the combustion engine 100 is at rest and the exhaust system 10 is cooling down in the ambient air, is drawn in by the suction body 40 and heated during combustion engine operation and the temperatures generated therein. The liquid quantity 50 then evaporates and exits the exhaust system 10 towards the environment U together with the exhaust gas 12.

[0023] Furthermore, the exhaust system 10 has a pressure device 60 by means of which the suction body 40 can be compressed, at least partially, in order to force the quantity of liquid 50 drawn in by the suction body 40 out of the suction body 40. A respective section plane of the in Fig. 1, Fig. 2 and Fig. The section shown in the 3 sectional views runs perpendicular to the flow direction of the exhaust gas 12 and through the suction body 40, whereby the schematically depicted pressure device 60 is recognizable.

[0024] The heat-resistant suction element 40, designed in this case as a sponge, is arranged in a geodetically lowest exhaust system interior area 22 of the exhaust system 10. The exhaust system interior area 22 forms the geodetically lowest point of an exhaust system interior 20 of the exhaust system 10.

[0025] The printing device 60 is in the Fig. 1, Fig. 2 and Fig. The exhaust system 10, shown in three abstracted variants, can generally be configured to compress the suction element 40 depending on the exhaust gas temperature 12. For temperature-dependent compression of the suction element 40, the pressure device 60 can, for example, have a bimetallic arrangement. It is also conceivable that the pressure device 60 can additionally or alternatively have a thermal expansion element for temperature-dependent compression of the suction element 40. In an optional embodiment, the pressure device 60 can additionally or alternatively have a spring element for temperature-dependent compression of the suction element 40. Additionally or alternatively, the pressure device 60 can have an electric motor and / or a mechanical cylinder for temperature-dependent compression of the suction element 40.It is conceivable that a differential pressure is generated, for example by means of a vacuum canister (not shown here) or via another pressure connection located outside the exhaust system 10, by means of which, for example, a pneumatic cylinder can be actuated to compress the suction body.

[0026] Fig. 1, Fig. 2 and Fig. Figure 3 shows that for all variants of the exhaust system 10, a housing 30 can be provided in which the suction element 40 can be securely arranged. The housing 30 thus forms an enclosure for the suction element 40. The pressure device 60 can also be accommodated in this housing 30. It is advantageous if the housing 30 has through-openings 32 through which the liquid quantity 50 can be exchanged between the suction element 40 and the exhaust system interior 20. For example, the liquid quantity 50 can flow from the exhaust system interior 20 through the through-openings 32 into an interior space 34 of the housing 30, in which the suction element 40 is arranged, in order to be drawn in by the suction element 40.If the liquid quantity 32 is heated by the influence of temperature, for example at an exhaust system wall 14 of the exhaust system 10, a housing wall 36 of the housing 30, or by the exhaust gas temperature 12, a partial phase change from the liquid phase to the gas phase can already occur, so that the gaseous component of the liquid quantity 32 can be carried away to the environment U with the exhaust gas 12. The pressure device 60 compresses the sponge (absorbent body 40 more strongly the higher the temperature at the respective wall or the higher the exhaust gas temperature rises, whereby liquid component of the liquid quantity 50 is forced out of the absorber 40 and evaporates in the exhaust system interior 20, which is heated by the exhaust gas, and is carried out of the exhaust system 10 to the environment U via the exhaust gas 12.When the pressure device 60 cools down after the combustion engine 100 has stopped, the pressure device 60 reduces the compression of the suction body 40 in a temperature-dependent manner. In other words, the suction body 40 is then relieved of pressure and can again be used to absorb liquid. The quantity of liquid 50, i.e., the condensate or water, is thus bound in the suction body 40 when the exhaust system 10 is cold. When a sufficiently high temperature is reached (at the wall or in the form of the exhaust gas temperature), the quantity of liquid 50 is forced out of the suction body 40 by the pressure device 60, evaporates, and is conveyed to the environment U via the exhaust gas 12.

[0027] Unlike the one in Fig. The first variant of the exhaust system 10 shown in 1 exhibits the following: Fig. 2 shown, second variant on the exhaust system wall 14, for example at the lowest geodetic point, at least one hole 16 through which at least part of the liquid quantity 50 can be released to the environment U.

[0028] In the Fig. In the third variant of the exhaust system 10 shown in Figure 3, a pipe 18 is provided which can open into the housing interior 34 of the housing 30 and through which at least some of the liquid quantity 50 can be released into the environment U. The pipe 18 makes it possible for the exhaust system to operate towards the environment U without boreholes such as the hole 16.

[0029] A check valve 70, as provided in the second and third variants of the exhaust system 10, may also be provided. During operation of the internal combustion engine 100, the check valve 70 can seal the passage openings 32 to the exhaust system interior 20 in a gas-tight manner. The check valve 70 may be designed to release the passage openings 32 to allow airflow when the exhaust system 10 is not in operation and is cooling down to ambient temperature or has already cooled down to ambient temperature. Reference symbol list 10 Exhaust system 12 Exhaust gas 14 Exhaust system wall 16 holes 18 pipe 20 Exhaust system interior 22 Exhaust system interior area 30 cases 32 Passage opening 34 Case interior 36 Housing wall 40 suction cups 50 liquid quantity 60 Printing device 70 Recoil mechanism 100 internal combustion engine K motor vehicle U surroundings

Claims

[1] Motor vehicle (K) with an internal combustion engine (100) and with an exhaust system (10), which - is designed to discharge exhaust gas (12) emitted by the internal combustion engine (100) to an environment (U) of the motor vehicle (K), - has a suction body (40) which is designed to at least partially absorb at least a quantity (50) of liquid formed in the exhaust system (10) and / or penetrating into the exhaust system (10) and - a pressure device (60) by means of which the absorbent body (40) can be compressed at least in some areas in order to press the amount of liquid (50) absorbed by the absorbent body (40) out of the absorbent body (40). [2] Motor vehicle (K) according to claim 1, characterized by that the absorbent body (40) is designed as a sponge. [3] Motor vehicle (K) according to claim 1 or 2, characterized bythat the pressure device (60) is designed to compress the suction body (40) depending on an exhaust gas temperature of the exhaust gas (12). [4] Motor vehicle (K) according to claim 3, characterized by that the pressure device (60) for temperature-dependent compression of the absorbent body (40) has a bimetal arrangement. [5] Motor vehicle (K) according to claim 3 or 4, characterized by that the pressure device (60) for temperature-dependent compression of the absorbent body (40) has an expansion element. [6] Motor vehicle (K) according to one of claims 3 to 5, characterized by that the pressure device (60) for temperature-dependent compression of the absorbent body (40) has a spring element. [7] Motor vehicle (K) according to one of claims 3 to 6, characterized by that the pressure device (60) for temperature-dependent compression of the absorbent body (40) has an electric motor and / or a mechanical cylinder. [8] Motor vehicle (K) according to one of the preceding claims, characterized by that the suction body (40) is arranged at a geodetically lowest exhaust system interior area (22) of the exhaust system (10). [9] Exhaust system (10) for a motor vehicle (K) according to one of claims 1 to 8.

Images