Internal combustion engine and motor vehicle

Abstract

Internal combustion engine of a motor vehicle, with at least one exhaust gas turbocharger (10, 11) comprising a turbine (12, 13) and a compressor (14, 15), wherein exhaust gas to be depressurized can be supplied to the turbine (12, 13) of the respective exhaust gas turbocharger (10, 11) and depressurized exhaust gas can be discharged from the turbine (12, 13) of the respective exhaust gas turbocharger (10, 11), wherein charge air (LL) to be compressed can be supplied to the compressor (14, 15) of the respective exhaust gas turbocharger (10, 11) via a first air line (16, 17) and compressed charge air (LL) can be discharged from the compressor (14, 15) of the respective exhaust gas turbocharger (10, 11) via a second air line (18, 19), with a venting system for a fuel tank of the motor vehicle, via which a fuel tank leakage (KL) can be discharged via a vent line (25) towards at least one activated carbon filter (26), and via which the fuel tank leakage (KL) routed via the respective activated carbon filter (26) can be mixed with charge air (LL) routed via a respective bypass line (27), which extends between the respective first air line (16, 17) and second air line (18, 19), and the respective first air line (16, 17) can be supplied for mixing with the charge air (LL) to be compressed, characterized by the fact that A check valve (29) is integrated into the respective first air line (16, 17), which prevents flow from the respective first air line (16, 17) towards the respective activated carbon filter (26), and a venturi nozzle (28) is integrated downstream of the check valve (29) in the direction of flow of the fuel tank leakage (KL), which serves to mix the fuel tank leakage (KL) with charge air (LL) flowing via the bypass line (27), such that outside the respective first air line (16, 17) only those sections of the respective vent line (25) which extend upstream of the respective check valve (29) in the direction of flow of the fuel tank leakage (KL), and those sections of the respective bypass line (27) which extend upstream of the respective venturi nozzle (28) in the direction of flow of the charge air (LL) are accessible.

Description

[0001] The invention relates to an internal combustion engine of a motor vehicle and a motor vehicle according to the preamble of claims 1 and 4 and a motor vehicle.

[0002] Fig. Figure 1 shows details of a state-of-the-art internal combustion engine. For example, in Fig. Figure 1 shows two exhaust gas turbochargers 10, 11, each comprising a turbine 12, 13 and a compressor 14, 15. The turbine 12, 13 of each exhaust gas turbocharger 10, 11 serves to expand the exhaust gas leaving the cylinders of the internal combustion engine. The energy recovered in this process can be used in the compressors 14, 15 of the exhaust gas turbochargers 10, 11 to compress the charge air LL supplied to the cylinders of the internal combustion engine. The cylinders of the internal combustion engine are housed in a cylinder crankcase (not shown), which also accommodates a crankshaft. The pistons of the cylinders are connected to the crankshaft via connecting rods. This is familiar to those skilled in the art.

[0003] Fig. Figure 1 shows the first charge air lines 16, 17, through which compressed charge air LL can be supplied to the compressors 14, 15 of the exhaust gas turbochargers 10, 11. Compressed charge air LL can be discharged from the exhaust gas turbochargers 10, 11 via second air lines 18, 19 and supplied to the cylinders of the internal combustion engine.

[0004] It is known from practice that an internal combustion engine has a ventilation system for the in Fig. 1. Cylinder crankcase not shown. A cylinder leakage ZL, flowing over the pistons of the cylinders, can be directed towards at least one oil separator 20, 21 via first return lines 22 of the ventilation system for the cylinder crankcase. In the exemplary embodiment of the Fig. In Figure 1, there are not only two exhaust gas turbochargers 10, 11, but also two oil separators 20, 21. The cylinders of the internal combustion engine are arranged in cylinder banks, with each cylinder bank having one exhaust gas turbocharger 10, 11 and one oil separator 20, 21.

[0005] Via further return lines 23 of the ventilation system for the cylinder crankcase, the cylinder leakage ZL, which has been routed via the respective oil separator 20, 21, can be routed further towards the cylinders of the internal combustion engine, such that, starting from the respective oil separator 20, 21, the cylinder leakage ZL can be supplied via the respective further return line 23 to the respective first charge air line 16, 17, in order to mix the cylinder leakage ZL, which has already been routed via the oil separators 20, 21, with the charge air LL to be compressed in the area of ​​the respective first charge air line 16, 17.

[0006] According to Fig. 2. According to the prior art, a check valve 24 is integrated into each of the respective return lines 23. If a section of the respective return line 23, extending between the respective oil separator 21, 22 and the respective check valve 24, is damaged, the damage can be detected by a pressure drop in the cylinder crankcase or in the respective oil separator. However, if a section of the respective return line 23, extending between the respective check valve 24 and the respective first air line 16, 17, is damaged, this damage cannot be detected. According to the prior art, an undetectable leakage caused by such damage then enters the environment. This is a disadvantage.

[0007] It is also known from practice that an internal combustion engine can have a fuel tank venting system. Fuel tank leakage KL can be discharged via a vent line 25 towards at least one activated carbon filter 26 through the fuel tank venting system. Furthermore, the fuel tank leakage KL, which is routed through the activated carbon filter 26, can be discharged via the vent line 25 from the respective activated carbon filter 26 to a bypass line 27 (see Fig. 3) can be supplied and mixed with charge air LL in the bypass line 27, which flows via the bypass line 27 from the second charge air line 18 towards the first charge air line 16.

[0008] The fuel leakage KL can be fed to the charge air LL to be compressed via the fuel tank's venting system in the area of ​​the respective first air line 16. According to the state of the art, the mixing of the fuel leakage KL with the charge air LL flowing from the respective second air line 18 towards the respective first air line 16 is carried out via a Venturi nozzle 28 integrated into the respective bypass line 27 (see Fig. 3) A check valve 29 is arranged upstream of the venturi nozzle 28 in the area of ​​the vent line 25. If the bypass line 27 downstream of the venturi nozzle 28 is damaged, the fuel leakage KL flowing through the activated carbon filter 26 will escape into the environment without being detected. This is a disadvantage.

[0009] EP 2 805 040 B1 discloses a venting system for the fuel tank of an internal combustion engine. Leakage from the fuel tank can be fed into the charge air, which flows via a bypass line from the compressed charge air towards the charge air to be compressed, i.e., from a high-pressure area of ​​the charge air system towards a low-pressure area. A Venturi nozzle is integrated into the bypass line.

[0010] DE 10 2016 210 570 A1 discloses a fuel tank venting module for an internal combustion engine. The fuel tank venting module has a suction pipe. A charging device is arranged in the suction pipe. Fuel leakage can be routed from the tank through a filter and from the filter through a line towards a fuel tank venting valve. In the direction of fuel leakage flow, check valves are arranged downstream of the fuel tank venting valve. The Venturi nozzle is positioned upstream or downstream of one of the check valves. Such sections of a line, extending downstream of the check valve in the direction of fuel leakage flow, are accessible outside the suction pipe.

[0011] DE 10 2019 106 039 A1 discloses an internal combustion engine of a motor vehicle according to the preamble of claim 4.

[0012] DE 11 2016 004 026 T5 reveals further state of the art.

[0013] As explained above, both the crankcase ventilation system and the fuel tank ventilation system of the internal combustion engine suffer from the problem that a leak, which should actually be directed towards the intake air to be compressed, escapes into the environment in the event of a defective line, without being detected. With increasingly stringent environmental regulations, this is unacceptable. A solution exists for an internal combustion engine in which such undetectable leaks in the fuel tank and / or crankcase ventilation systems can be prevented.

[0014] The object of the invention is to create a novel internal combustion engine for a motor vehicle and a motor vehicle.

[0015] According to a first aspect of the invention, this problem is solved by an internal combustion engine according to claim 1. According to the first aspect of the invention, a check valve, which prevents flow from the respective first air line towards the respective activated carbon filter, and a Venturi nozzle, which serves to mix the fuel tank leakage with charge air, are integrated into the respective first air line in such a way that, outside the respective first air line, only those sections of the respective vent line which extend upstream of the respective check valve in the direction of fuel tank leakage and those sections of the respective bypass line which extend upstream of the respective Venturi nozzle in the direction of charge air flow are accessible.

[0016] The first aspect of the invention prevents undetectable leakage in the fuel tank venting system. If damage occurs in the vent line, it can only occur in the section upstream of the venting system, because the respective check valve and venturi nozzle of the fuel tank venting system are integrated into the first air line. Therefore, any leakage in this area can always be reliably detected.

[0017] According to a second aspect of the invention, this problem is solved by an internal combustion engine according to claim 4. According to the second aspect of the invention, a check valve is integrated into the respective first air line, which prevents flow through the respective return line from the respective first air line towards the respective oil separator, such that only those sections of the respective return line are accessible outside the respective first air line which extend upstream of the respective check valve in the direction of flow of the cylinder leakage.

[0018] The second aspect of the invention prevents undetectable leakage from the crankcase ventilation system. For this purpose, the respective check valve of the crankcase ventilation system is integrated into the first air line. Therefore, damage to the line can only occur upstream of the respective check valve, and this damage can also be detected via a corresponding pressure drop in the crankcase.

[0019] The motor vehicle is defined in claim 7.

[0020] Both aspects are particularly favored when used in combination on an internal combustion engine.

[0021] Preferred embodiments of the invention are described in the dependent claims and the following description. Exemplary embodiments of the invention are explained in more detail with reference to the drawing, without being limited thereto. The drawing shows: Fig. 1 Components of an internal combustion engine according to the state of the art; Fig. 2 details of the Fig. 1; Fig. 3 more details of the Fig. 1; Fig. 4 Details of an internal combustion engine according to the invention according to a first aspect of the invention; Fig. 5 Details of an internal combustion engine according to the invention according to a second aspect of the invention; Fig. 6 a first cross-section through Fig. 5; and Fig. 7 a second cross-section through Fig. 5.

[0022] The invention relates to an internal combustion engine, namely a turbocharged internal combustion engine with at least one exhaust gas turbocharger, and a motor vehicle.

[0023] The basic design of such an internal combustion engine is familiar to the expert addressed here and has already been described with reference to Fig. 1 described.

[0024] For the sake of completeness, it should be noted again that an internal combustion engine has a cylinder crankcase that houses a crankshaft and pistons of cylinders. The pistons of the cylinders are connected to the crankshaft via connecting rods. The cylinders can preferably be arranged in several cylinder banks, which are oriented in a V-configuration or boxer configuration relative to each other.

[0025] An internal combustion engine further comprises at least one turbocharger 10, 11. If the cylinders are arranged in two cylinder banks, preferably two exhaust gas turbochargers 10, 11 are present. Such an exhaust gas turbocharger 10, 11 has a turbine 12, 13 in which exhaust gas from the cylinders of the internal combustion engine is expanded in order to recover energy. Furthermore, an exhaust gas turbocharger 10, 11 has a compressor 13, 14 in which charge air LL supplied to the internal combustion engine can be compressed.

[0026] Exhaust gas from the cylinders can be supplied to each turbine 12, 13 via a first exhaust line. The expanded exhaust gas can then be discharged from the respective turbine of the respective exhaust gas turbocharger via a second exhaust line, for example towards an exhaust aftertreatment system.

[0027] Charge air LL to be compressed can be supplied to the respective compressor 14, 15 of the respective exhaust gas turbocharger via a first air line 16, 17. The charge air LL compressed in the respective compressor 14, 15 can be discharged from the respective exhaust gas turbocharger, namely from the compressor 14, 15 thereof, via a second air line 18, 19, in the direction of the cylinders of the internal combustion engine.

[0028] In an internal combustion engine according to a first aspect of the invention, the engine comprises a venting system for a fuel tank. A fuel tank leakage KL can be discharged via such a venting system through a vent line 25 towards an activated carbon filter 26. From the activated carbon filter 26, the fuel leakage KL, having passed through the activated carbon filter 26, can be fed via the vent line 25 to a respective bypass line 27, which extends between the respective second charge air line 18 and the respective first charge air line 16. A Venturi nozzle 28 is arranged in the region of this bypass line 27, through which the fuel leakage KL is introduced into the charge air LL, which flows via the bypass line 27 from the respective second air line 18, in which compressed charge air LL is present, towards the first air line 16, in which charge air LL to be compressed is present.The connection between these two air ducts 16, 18 is thereby in . Fig. 4 is provided via an intermediate piece 30, which is arranged upstream of the Venturi nozzle 28.

[0029] After the first aspect of the invention (see Fig. 4) Not only is the respective venturi nozzle 28, which serves to mix the fuel leakage KL with charge air LL, integrated into the respective first charge air line 16, but also the respective check valve 29, which prevents flow from the respective first charge air line 16 or the respective second charge air line 18 towards the respective activated carbon filter 26. Accordingly, only those sections of the respective vent line 25 that extend upstream of the respective check valve 29 in the direction of flow of the fuel leakage KL, and those sections of the bypass line 27 that are positioned upstream of the venturi nozzle 28 in the direction of flow of the charge air LL, extend outside the respective first charge air line 16, so that in the event of damage to the bypass line 27 or the vent line 25, the damage is detectable.This prevents undetectable damage to the fuel tank venting system and undetectable fuel leakage KL into the environment.

[0030] Outside of the respective first air line 16, 17, only those sections of the respective vent line 25 are accessible that extend between the check valve 29 and the activated carbon filter 26 or the fuel tank. Outside of the respective first air line 16, 17, only those sections of the respective bypass line 27 are accessible that extend between the venturi nozzle 28 and the second air line 18, 19.

[0031] Fig. 5, Fig. 6 and Fig. Figure 7 shows details of an internal combustion engine which, according to the second aspect of the invention, namely in Fig. 5, Fig. 6 and Fig.7 in addition to the venting system for the fuel tank, the venting system for the cylinder crankcase has a through which a cylinder leakage ZL flowing over the pistons of the cylinders can be directed towards the respective oil separator 20, 21 and from the respective oil separator 20, 21 towards the respective first charge air line 16, 17 in order to mix the cylinder leakage ZL of the cylinder crankcase, which is directed over the respective oil separator 20, 21, in the area of ​​the respective first charge air line 16, 17 with charge air to be compressed.

[0032] According to the second aspect of the invention, the check valve 24, which prevents the flow through the respective return line 23 from the respective charge air line 16, 17 towards the respective oil separator 20, 21, is integrated into the respective first charge air line 16 in such a way that only those sections of the respective vent line 23 that extend between the respective oil separator 20, 21 and the respective check valve 24 run outside the respective first charge air line 16, 17, i.e., those sections of the respective return line 23 that extend upstream of the respective check valve 24, are accessible. This prevents undetectable leakage from occurring in the crankcase ventilation system.

Claims

[1] Internal combustion engine of a motor vehicle, with at least one exhaust gas turbocharger (10, 11) comprising a turbine (12, 13) and a compressor (14, 15), wherein exhaust gas to be depressurized can be supplied to the turbine (12, 13) of the respective exhaust gas turbocharger (10, 11) and depressurized exhaust gas can be discharged from the turbine (12, 13) of the respective exhaust gas turbocharger (10, 11), wherein charge air (LL) to be compressed can be supplied to the compressor (14, 15) of the respective exhaust gas turbocharger (10, 11) via a first air line (16, 17) and compressed charge air (LL) can be discharged from the compressor (14, 15) of the respective exhaust gas turbocharger (10, 11) via a second air line (18, 19), with a venting system for a fuel tank of the motor vehicle, via which a fuel tank leakage (KL) can be discharged via a vent line (25) towards at least one activated carbon filter (26), and via which the fuel tank leakage (KL) routed via the respective activated carbon filter (26) can be mixed with charge air (LL) routed via a respective bypass line (27), which extends between the respective first air line (16, 17) and second air line (18, 19), and the respective first air line (16, 17) can be supplied for mixing with the charge air (LL) to be compressed, characterized by , that A check valve (29) is integrated into the respective first air line (16, 17), which prevents flow from the respective first air line (16, 17) towards the respective activated carbon filter (26), and a venturi nozzle (28) is integrated downstream of the check valve (29) in the direction of flow of the fuel tank leakage (KL), which serves to mix the fuel tank leakage (KL) with charge air (LL) flowing via the bypass line (27), such that outside the respective first air line (16, 17) only those sections of the respective vent line (25) which extend upstream of the respective check valve (29) in the direction of flow of the fuel tank leakage (KL), and those sections of the respective bypass line (27) which extend upstream of the respective venturi nozzle (28) in the direction of flow of the charge air (LL) are accessible. [2] Internal combustion engine according to claim 1, characterized by, that outside the respective first air line (16, 17) only those sections of the respective vent line (25) are accessible which extend between the check valve (29) and the activated carbon filter (26) or the fuel tank. [3] Internal combustion engine according to claim 1 or 2, characterized by , that outside the respective first air line (16, 17) only those sections of the respective bypass line (27) are accessible which extend between the venturi nozzle (28) and the second air line (18, 19). [4] Internal combustion engine of a motor vehicle, with a cylinder crankcase that accommodates a crankshaft and pistons of cylinders that are coupled to the crankshaft via connecting rods, with at least one exhaust gas turbocharger (10, 11) comprising a turbine (12, 13) and a compressor (14, 15), wherein exhaust gas to be depressurized can be supplied to the turbine (12, 13) of the respective exhaust gas turbocharger (10, 11) and depressurized exhaust gas can be discharged from the turbine (12, 13) of the respective exhaust gas turbocharger (10, 11), wherein charge air (LL) to be compressed can be supplied to the compressor (14, 15) of the respective exhaust gas turbocharger (10, 11) via a first air line (16, 17) and compressed charge air (LL) can be discharged from the compressor (14, 15) of the respective exhaust gas turbocharger (10, 11) via a second air line (18, 19), with a ventilation system for the cylinder crankcase, through which a cylinder leakage (ZL) flowing over the pistons of the cylinders can be discharged towards at least one oil separator (20, 21), and through which, starting from the respective oil separator (20, 21), the cylinder leakage (ZL) can be supplied via a respective return line (23) to the respective first air line (16, 17) for mixing the cylinder leakage (ZL) with the charge air (LL) to be compressed, characterized by , that A check valve (24) is integrated into the respective first air line (16, 17), which prevents flow through the respective return line (23) from the respective first air line (16, 17) towards the respective oil separator (20, 21), in such a way that outside the respective first air line (16, 17) only those sections of the respective return line (23) are accessible which extend upstream of the respective check valve (24) in the direction of flow of the cylinder leakage (ZL). [5] Internal combustion engine according to claim 4, characterized by , that outside the respective first air line (16, 17) only those sections of the respective return line (23) are accessible which extend between the respective oil separator (20, 11) and the respective check valve (24). [6] Internal combustion engine according to claim 4 or 5, characterized bythat the same is further developed according to one of claims 1 to 3. [7] Motor vehicle with an internal combustion engine according to any one of claims 1 to 6.

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