Internal combustion engine for a motor vehicle, and motor vehicle

Abstract

The invention relates to an internal combustion engine (1) for a motor vehicle, with a crankcase (2), with an inlet section (4) through which air can flow, and with a tank ventilation means (14) which is provided to ventilate a fuel tank (13) and has a first suction jet pump (15), to which at least a first part of the air from the inlet section (14) can be fed in order to ventilate the fuel tank (13), with the result that, in order to ventilate the fuel tank (13), a first gas can be sucked in as first suction medium from the fuel tank (13) by means of the first suction jet pump (15) with utilization of the air fed in to the first suction jet pump (15) as first propellant. The tank ventilation means (14) comprises a first mixture line (16) through which a first mixture which comprises the first suction medium and the first propellant can flow. A crankcase ventilation means (18) is provided which has a second suction jet pump (19), to which at least a second part of the air from the inlet section (4) can be fed in order to ventilate the crankcase (2).

Description

[0001] Internal combustion engine for a motor vehicle and motor vehicle

[0002] The invention relates to an internal combustion engine for a motor vehicle, in particular for a car. Furthermore, the invention relates to a motor vehicle with such an internal combustion engine.

[0003] EP 3 020 934 B1 discloses a known vehicle having an internal combustion engine with a crankcase and a supercharging device. Also provided is a crankcase ventilation device having at least one inertia-based oil separation device with at least one inertia-based oil separator, an oil return line returning separated oil to the crankcase, and a suction jet pump driven by compressed air from the supercharging device and generating a vacuum to drive blow-by gas. Furthermore, EP 2 815 089 B1 discloses a vehicle having an internal combustion engine with a crankcase. Also provided is a crankcase ventilation device having at least one oil separation device and an oil return line returning separated oil to the crankcase. Also provided is a conveying device for driving a fluid other than blow-by gas.The conveyor is also used to drive the blow-by gas in the crankcase ventilation system.

[0004] The object of the present invention is to provide an internal combustion engine for a motor vehicle and a motor vehicle with such an internal combustion engine, so that a particularly advantageous crankcase ventilation can be realized.

[0005] This object is achieved by an internal combustion engine having the features of patent claim 1, by an internal combustion engine having the features of patent claim 9 and by a motor vehicle having the features of patent claim 10.

[0006] A first aspect of the invention relates to an internal combustion engine, also referred to as an internal combustion engine, motor or combustion engine and preferably designed as a reciprocating piston engine, thus as a reciprocating piston machine, for a motor vehicle, also simply referred to as a vehicle. This means that the motor vehicle, preferably designed as a motor vehicle, in particular as a passenger car, in its fully manufactured state has the internal combustion engine and can be driven by means of the internal combustion engine. The internal combustion engine has a crankcase. For example, the internal combustion engine has an output shaft designed as a crankshaft, which is mounted on the crankcase so as to be rotatable about a shaft axis of rotation relative to the crankcase. The internal combustion engine can provide drive torques for driving the motor vehicle via the crankshaft.The internal combustion engine also has an intake tract through which air can flow, which is also referred to as the intake tract. The air flowing through the intake tract is also referred to as combustion air or fresh air. The internal combustion engine has a tank venting device by means of which a fuel tank can be vented. The tank venting device is a first venting device or is also referred to as a first venting device. In particular, a preferably liquid fuel for operating the internal combustion engine, in particular during its fired operation, can be or is at least temporarily accommodated in the fuel tank. The tank venting device has a first suction jet pump, which is also referred to as a first jet pump or is designed as a first jet pump.To vent the fuel tank, at least a first portion of the air from the intake tract can be supplied to the first suction jet pump, so that to vent the fuel tank by means of the first suction jet pump, a first gas can be sucked in from the fuel tank as the first suction medium using the air supplied to the first suction jet pump as the first propulsion medium for the first suction jet pump. The first gas can comprise, for example, unburned hydrocarbons (HC), which are or can be outgassed from the preferably liquid fuel held or capable of being held in the fuel tank. Thus, for example, during operation of the internal combustion engine, the first portion of the air from the intake tract is supplied to the suction jet pump, wherein the first portion of the air from the intake tract (intake tract) is used as the first propulsion medium for the first suction jet pump.The first suction jet pump is operated by the first propellant medium, such that the first gas is sucked out of the fuel tank by the first suction jet pump using the first propellant medium and thus by the first propellant medium. This means that the first gas is the first suction medium, which is sucked in by the first suction jet pump and with the aid of the first propellant medium and is thus conveyed out of the fuel tank, thereby venting the fuel tank. The tank venting device has a first mixture line through which a first mixture comprising the first suction medium and the first propellant medium can flow.This means that during the aforementioned operation, the first drive medium and the first suction medium flow through at least a part of the first suction jet pump and mix, thereby forming the first mixture, which flows through the first mixture line and is discharged from the suction jet pump in particular by means of the first mixture line.

[0007] The internal combustion engine also has a crankcase ventilation system, which is also simply referred to as a crankcase ventilation system. The crankcase ventilation system is a second ventilation system or is also referred to as a second ventilation system. The crankcase ventilation system has a second suction jet pump, which is also referred to as a second jet pump or is designed as a second suction jet pump. In particular, the second suction jet pump is provided in addition to the first suction jet pump, in particular such that the second suction jet pump is an external component with respect to the first suction jet pump and is thus arranged outside the first suction jet pump.Accordingly, it is preferably provided that the first suction jet pump is a suction jet pump provided in addition to the second suction jet pump, in particular such that the first suction jet pump is an external component with respect to the second suction jet pump, and is therefore arranged outside the second suction jet pump. At least a second portion of the air from the intake tract can be supplied to the second suction jet pump for venting the crankcase, so that for venting the crankcase by means of the second suction jet pump, a second gas can be sucked in from the crankcase as a second suction medium using the air supplied to the second suction jet pump as a second propulsion medium for the second suction jet pump. In other words, during the aforementioned operation or during further operation of the internal combustion engine, the second portion of the air from the intake tract is supplied to the second suction jet pump.The second part of the air is used as the second driving medium for the second suction jet pump, so that by means of the second suction jet pump, using the second driving medium and thus by means of the second driving medium, the second gas is sucked out of the crankcase and thus pumped out of the crankcase, whereby the crankcase is vented. The second gas is thus the so-called second suction medium, which is sucked out of the crankcase by means of the second suction jet pump and with the help of the second driving medium and thus pumped out of the crankcase. By venting the fuel tank, which is also simply referred to as the tank, by venting the crankcase, for example, excessive pressure in the crankcase or in the tank can be avoided.The second gas comprises, for example, so-called blow-by gas, which originates, for example, from at least one combustion chamber of the internal combustion engine and flows between a piston and a corresponding cylinder wall of the internal combustion engine, thereby flowing into the crankcase, in particular into a crankcase of the crankcase. By means of the second suction jet pump and the second propellant medium, the crankcase, and thus the crankcase, can be effectively and efficiently vented.

[0008] The crankcase ventilation device also has a second mixture line through which a second mixture comprising the second suction medium and the second propellant medium can flow. This means that the second suction medium and the second propellant medium flow through at least part of the second suction jet pump, mix and thereby form the second mixture, which can flow through the second mixture line and in particular can be discharged from the second suction jet pump by means of the second mixture line. The second mixture can be introduced into the intake tract at an inlet point via or by means of the second mixture line. For this purpose, for example, the second mixture formation is or can be fluidly connected to the intake tract at the inlet point. For example, the second mixture line opens into the intake tract at the inlet point.The first mixture line is fluidically connected to the second mixture line at a connection point arranged downstream of the second suction jet pump and upstream of the introduction point and in particular in the second mixture line, so that, for example, the first mixture line opens into the second mixture line at the connection point. At the connection point, the first mixture from the first mixture line can be introduced into the second mixture line. If, for example, the first mixture is introduced from the first mixture line into the second mixture line at the connection point, in particular during the aforementioned operation, the first mixture introduced into the second mixture line at the connection point can then flow through a length region of the first mixture line, the length region of which extends, for example, from the connection point to the introduction point, in particular continuously.Thus, the first mixture can be introduced into the intake tract at the inlet point via the first mixture line, in particular over the length of the first mixture line. With the invention, the second gas can be discharged from the crankcase in a particularly advantageous manner, so that particularly advantageous crankcase ventilation can be realized. For example, the crankcase ventilation has an oil separator via which the second suction medium can be fed to the second suction jet pump. Thus, for example, the second suction jet pump can suck in the second suction medium via the oil separator, so that the second suction medium flows through the oil separator on its way from the crankcase to the second suction jet pump. By means of the oil separator, any oil contained in the second gas can be separated from the gas.The oil separator is very preferably designed as a, in particular purely passive, oil separator, by means of which a, in particular purely passive, oil separation can be carried out in order to thereby separate any oil contained in the second suction medium from the second gas. In particular, the second suction jet pump, the second mixture line, and preferably also the oil separator are components of a full-load crankcase ventilation system, by means of which the crankcase is to be vented or is vented at full load of the internal combustion engine. Passive crankcase ventilation systems are common, although active crankcase ventilation systems are also known.Both passive crankcase ventilation systems and active crankcase ventilation systems separate any oil contained in the second gas via a pressure gradient with corresponding acceleration, particularly of the oil and, for example, of the second gas. Heavy oil droplets, for example, are typically separated from a main stream of the second gas by centrifugal force and thus separated from the second gas. The degree of separation achievable by the oil separator is typically tied to the pressure gradient and can therefore be undesirably limited. This can result in an undesirably high residual oil content, and thus an undesirably high amount of non-separated oil, in the second gas, particularly when the internal combustion engine is operating at full load.Oil that is not separated in the second gas has a tendency to coke and settle on hot components, which can result in an undesirable reduction in cross-section and thus an undesirable reduction in flow cross-sections. With the invention, it is now possible, in particular with the second suction jet pump, to generate an additional pressure gradient and thereby, for example, to reduce the pressure prevailing in the crankcase compared to conventional pressures, thus achieving an advantageously low pressure in the crankcase. This additional reduction in the pressure prevailing in the crankcase, which can be brought about by the second suction jet pump, can be used, for example, to set an advantageously high pressure gradient at an oil separator, so that an advantageously high separation efficiency of the oil separator can be achieved. Furthermore, with the invention, the second gas can be sucked out of the crankcase effectively and efficiently.

[0009] The feature that the second suction jet pump and the second mixture line, and preferably the oil separator, are components of the aforementioned full-load crankcase ventilation, which is also referred to as full-load ventilation, is to be understood in particular as meaning that the second mixture line and the second suction jet pump, and preferably also the oil separator, are arranged in a so-called full-load path, via which the crankcase is to be vented or is vented when the internal combustion engine is at full load. In particular, if the oil separator is a passive oil separator, in particular a purely passive one, the use of the second suction jet pump can achieve a high separation efficiency of the oil separator. In particular, pressure losses caused by the passive oil separator, for example, can be compensated for.Furthermore, the invention enables particularly advantageous scavenging of the crankcase, in particular of the crank chamber, also referred to as ventilation. For this purpose, an air flow, also referred to as air flow, can be formed as a scavenging air flow, which is or is formed, for example, by air originating from the intake tract, which flows from the intake tract via the first suction jet pump and via the first mixture line at the connection point into the second mixture line and then flows, for example, through a second length section of the second mixture line, the second length section of which extends from the connection point, in particular continuously and thus without interruption, to the second suction jet pump.The purge air flow, i.e. the air forming the purge air flow and originating from the intake tract, can thus, for example, flow via the second length region of the second mixture line to the second suction jet pump and subsequently flow through the second suction jet pump, in particular in a flow direction that is opposite to a further flow direction in which, for example, the second suction medium and / or the second drive medium flows through the second suction jet pump when the crankcase is vented by means of the second suction jet pump. The purge air flow and thus the air forming the purge air flow can thus flow through the second suction jet pump and flow from the second suction jet pump into the crankcase, whereby the crankcase is purged and thus ventilated.For example, the second suction medium can be supplied to the second suction jet pump via a suction line which is or can be connected fluidically to the crankcase, in particular to the crank chamber, and fluidically to the second suction jet pump, so that the second suction medium can be introduced from the crankcase into the suction line and supplied to the second suction jet pump by means of the suction line, which can thus be supplied with the second suction medium from the crankcase via the second suction line. Thus, for example, the purge air flow, i.e. the air forming the purge air flow, can flow from the second suction jet pump through the suction line, in particular in a flow direction that is opposite to a flow direction in which the second suction medium flows through the suction line when the crankcase is vented by means of the second suction jet pump.The purge air flow can flow through the intake line and thereby flow from the second suction jet pump into the crankcase via the intake line, thus being introduced into the crankcase by means of the suction jet pump via the intake line, whereby the crankcase can be advantageously purged. In particular, the purge air flow can develop at partial load, i.e., during partial load operation of the internal combustion engine, and / or when the internal combustion engine is operated in a non-charged characteristic map range, i.e., when the internal combustion engine is operated in a range of its characteristic map in which, in particular, active charging of the internal combustion engine by means of a compressor arranged, for example, in the intake tract, is omitted.Alternatively or additionally, for example, a purge air flow can be formed from the inlet tract, which flows through a drive line by means of which the second suction jet pump can be supplied with the second drive medium, and is thus guided to the second suction jet pump by means of the drive line, then flows through the second suction jet pump and then the suction line and thus flows into the crankcase via the drive line, the second suction jet pump and the suction line. As a result, the crankcase can be advantageously purged, i.e. ventilated. This means, for example, that an additional purge or ventilation line can be dispensed with. By purging the crankcase, for example, the crankcase can be dried and / or fuel can be advantageously discharged from the crankcase.Since the air forming the scavenging air flow originates from the intake tract, the air forming the scavenging air flow is fresh air, which allows the crankcase to be scavenged particularly advantageously.

[0010] In order to be able to realize particularly advantageous ventilation of the crankcase, particularly when the internal combustion engine is operating at full load, an advantageous embodiment of the invention provides a check valve which is arranged in the second mixture line downstream of the connection point and opens, in particular automatically, in the direction of the intake tract and closes in the direction of the connection point. The feature that the check valve is arranged downstream of the connection point is to be understood as meaning that the check valve is arranged downstream of the connection point with respect to a first flow direction, wherein when the crankcase is vented by means of the second suction jet pump, the second mixture flows through the second mixture line in the first flow direction.The check valve thus opens, in particular automatically, in the first flow direction, and the check valve thus closes or blocks, in particular automatically, in a flow direction opposite to the first flow direction. Thus, the check valve, in particular automatically, opens the mixture line for a fluid flow flowing through the mixture line in the first flow direction and thus flowing into the intake tract via the mixture line at the inlet point, whereby the crankcase can be advantageously vented, particularly when the internal combustion engine is operating at full load.For an opposite fluid flow flowing from the inlet point through the second mixture line in the second flow direction via the check valve, the check valve blocks the second mixture line, in particular automatically, so that an undesirable flow, in particular backflow, of a fluid from the inlet tract toward the second suction jet pump or toward the connection point can be prevented. In particular, the fluid can be, for example, the air flowing through the intake tract (inlet tract).

[0011] A further embodiment is characterized in that the inlet tract has a supply point. At the supply point, the first part of the air flowing through the inlet tract can be branched off from the inlet tract and fed as the first propulsion medium to the first suction jet pump. In other words, for example, during the aforementioned operation, the first part of the air flowing through the inlet tract is branched off from the inlet tract at the supply point and fed to the first suction jet pump. Alternatively or additionally, the second part of the air flowing through the inlet tract can be branched off from the inlet tract at the supply point and fed as the second propulsion medium to the second suction jet pump.Thus, for example, during the aforementioned operation or during the aforementioned further operation at the supply point, the second part of the air flowing through the inlet tract is diverted from the inlet tract and fed to the second suction jet pump.

[0012] It has proven particularly advantageous if the supply point is located downstream of a throttle valve arranged in the intake tract, by means of which the amount of air flowing through the intake tract to be supplied to the aforementioned combustion chamber of the internal combustion engine can be adjusted. This allows, for example, the crankcase to be advantageously ventilated.

[0013] Alternatively, it has proven particularly advantageous if the supply point is located upstream of the throttle valve located in the intake tract. This allows, for example, the aforementioned purge air flow to develop advantageously, thus enabling particularly advantageous purging of the crankcase in a simple, cost-effective, space-saving, and weight-efficient manner.

[0014] The feature that the supply point is arranged downstream or upstream of the throttle valve is to be understood as meaning that the supply point, in particular in the intake tract, is arranged upstream or downstream of the throttle valve with respect to an air flow direction, wherein the intake tract can be or is flowed through by the air in the air flow direction in order to thereby supply the air to the combustion chamber of the internal combustion engine.

[0015] It has proven particularly advantageous if the first venting device has a first supply line fluidly connected to the first suction jet pump and, at a first branching point, fluidly connected to the inlet tract, by means of which first supply line at least a portion of the air flowing through the inlet tract can be branched off from the inlet tract at the first branching point and introduced into the first supply line as supply air. This means that the portion of the air flowing through the inlet tract is referred to as supply air, wherein the portion of the air flowing through the inlet tract is branched off from the inlet tract at the first branching point and introduced into the supply line, particularly during the aforementioned operation.The supply air, i.e., the portion of the air flowing through the inlet tract branched off from the first branching point and introduced into the first supply line, can flow through the first supply line. A second supply line is provided, which is fluidly connected to the first supply line at a second branching point located downstream of the first branching point and upstream of the first suction jet pump, and thus branches off from the first supply line at the second branching point.The feature that the second branching point is arranged downstream of the first branching point and upstream of the first suction jet pump is to be understood as meaning that the second branching point is arranged downstream of the first branching point and upstream of the first suction jet pump with respect to a driving medium flow direction, wherein the first driving medium can flow or flows through the first supply line in the driving medium flow direction in order to thereby supply the first suction jet pump with the first suction medium. By means of the second supply line, a second part of the supply air can be branched off from the first supply line at the second branching point, while leaving a first part of the supply air in the first supply line, and can be introduced into the second supply line as the second driving medium.In other words, for example during the aforementioned operation, the aforementioned second part of the supply air is branched off from the first supply line at the second branching point by means of the second supply line and introduced into the second supply line, the branched-off second part of the supply air being used as the second driving medium and being supplied to the second suction jet pump. However, not all of the supply air is branched off from the first supply line, but rather the aforementioned first part of the supply air is left in the first supply line. The second driving medium can be supplied to the second suction jet pump by means of the second supply line. The first part of the supply air left or remaining in the first supply line can be or is supplied to the second suction jet pump as the driving medium by means of the first supply line.Thus, a particularly advantageous, space-saving and cost-effective supply of the suction jet pumps with the driving media can be realized, so that both a particularly advantageous ventilation of the fuel tank and a particularly advantageous ventilation of the crankcase can be achieved.

[0016] It has proven particularly advantageous if the supply point is the first branch point and thus a common supply point for the suction jet pumps, through which the suction jet pumps can be supplied with the propellant media from the intake tract. This allows both advantageous venting of the fuel tank and particularly advantageous venting of the crankcase to be achieved in a simple, cost-effective manner.

[0017] A further embodiment is characterized in that a pressure sensor is arranged in the second supply line upstream of the second suction jet pump and downstream of the second branching point, by means of which a pressure prevailing in the second supply line can be detected. This is to be understood in particular that the pressure sensor is arranged upstream of the second suction jet pump and downstream of the second branching point in the second supply line with respect to a second driving medium flow direction, wherein the second driving medium can flow through or is flowed through the second supply line in the second driving medium flow direction in order to supply the second suction jet pump with the second driving medium.

[0018] A second aspect of the invention relates to an internal combustion engine, also referred to as an internal combustion engine, motor or internal combustion engine and preferably designed as a reciprocating piston engine, thus as a reciprocating piston machine, for a motor vehicle, also simply referred to as a vehicle. The internal combustion engine according to the second aspect of the invention has a crankcase and an intake tract through which air can flow, which is also referred to as the intake tract. Furthermore, the internal combustion engine according to the second aspect of the invention has a throttle valve arranged in the intake tract, by means of which throttle valve a quantity of air flowing through the intake tract, also referred to as combustion air or fresh air, to be supplied to at least one combustion chamber of the internal combustion engine can be adjusted.The internal combustion engine according to the second aspect of the invention further comprises a crankcase ventilation device, which also comprises a suction jet pump. To vent the crankcase, at least a portion of the air from the intake tract can be supplied to the suction jet pump, so that, to vent the crankcase, a gas can be drawn in from the crankcase as a suction medium by means of the suction jet pump, using the air supplied to the suction jet pump as the driving medium for the suction jet pump.

[0019] In order to achieve particularly advantageous crankcase ventilation, particularly at full load of the internal combustion engine, the second aspect of the invention provides that a supply point, at which at least part of the air can be branched off from the intake tract as the propellant, is arranged downstream of the throttle valve in the flow direction of the air flowing through the intake tract and, in particular, toward the combustion chamber. Advantages and advantageous embodiments of the first aspect of the invention are to be regarded as advantages and advantageous embodiments of the second aspect of the invention, and vice versa.

[0020] A third aspect of the invention relates to a motor vehicle, also simply referred to as a vehicle and preferably designed as a motor vehicle, in particular a passenger car, which has an internal combustion engine according to the first aspect or according to the second aspect of the invention and is drivable by means of the internal combustion engine. Advantages and advantageous embodiments of the first aspect and the second aspect of the invention are to be regarded as advantages and advantageous embodiments of the third aspect of the invention, and vice versa.

[0021] Further details of the invention will become apparent from the following description of a preferred embodiment with the accompanying drawing. The sole FIG. 1 shows a schematic representation of an internal combustion engine for a motor vehicle.

[0022] Fig. 1 shows a schematic representation of an internal combustion engine 1, also referred to as an internal combustion engine, motor or combustion engine, and designed as a reciprocating piston engine, thus as a reciprocating piston machine, for a motor vehicle, also simply referred to as a vehicle. The internal combustion engine 1 has a crankcase 2, through which, for example, several cylinders 3 of the internal combustion engine 1 are formed. Thus, the crankcase 2 is designed, for example, as a cylinder crankcase. A respective combustion chamber of the internal combustion engine 1 is partially formed by each cylinder 3. The internal combustion engine 1 also has an intake tract 4, also referred to as an intake tract, through which air, which is also referred to as fresh air or combustion air, can flow. By means of the intake tract 4, the air flowing through the intake tract 4 can be guided to and into the combustion chambers. In Fig.In Figure 1, arrows 5 illustrate a first flow direction, also referred to as the air flow direction. Air can or does flow through the intake tract 4 in the air flow direction, thereby directing the air to and into the combustion chambers. In other words, the air flows through the intake tract 4 in the air flow direction on its way through the intake tract 4 toward and into the combustion chambers.

[0023] An air filter 6 is arranged in the intake tract 4, by means of which the air flowing through the intake tract 4 is filtered. The internal combustion engine 1 also has an exhaust tract 7, through which exhaust gas from the combustion chambers can flow. In Fig. 1, an arrow 8 illustrates a second flow direction in which the exhaust gas from the combustion chambers flows or can flow through the exhaust tract 7, whereby the exhaust gas can be discharged from the combustion chambers. In the embodiment shown in Fig. 1, the internal combustion engine 1 has an exhaust gas turbocharger 9, which has a compressor 10 arranged in the intake tract 4 and a turbine 11 arranged in the exhaust tract 7. The turbine 11 can be driven by the exhaust gas flowing through the exhaust tract 7.The turbine 11 can drive the compressor 10 via a shaft 12 of the exhaust gas turbocharger 9. By driving the compressor 10, the air flowing through the intake tract 4 can be compressed, and thus supercharged, by means of the compressor 10. The combustion chambers of the internal combustion engine 1 can thus be supplied with the air compressed by the compressor 10, which is also referred to as supercharging or supercharging of the internal combustion engine 1. For example, the internal combustion engine 1 is operated in a supercharged mode at least in a first region of its characteristic map, so that in the first region of the characteristic map, also referred to as the first region of the characteristic map, the combustion chambers are supplied with air from the intake tract 4 compressed by the compressor 10. For example, in at least a second region of the characteristic map, the internal combustion engine 1 is operated in a non-supercharged mode.The second area of ​​the map is also referred to as the second area of ​​the map or the non-charged area of ​​the map. In the second area of ​​the map, for example, the combustion chambers are not supplied with air compressed by the compressor 10, wherein the combustion chambers are supplied with air from the intake tract 4, but the air with which the combustion chambers are supplied is not charged by the compressor 10. For example, the first area of ​​the map is or includes a full load, i.e., full-load operation of the internal combustion engine 1. Furthermore, it is conceivable that the second area of ​​the map is or includes a partial load, i.e., partial-load operation of the internal combustion engine 1.

[0024] The internal combustion engine 1 is operable in its fired mode using a preferably liquid fuel. During fired mode, a fuel-air mixture is combusted in the respective combustion chamber within a respective working cycle of the internal combustion engine 1, resulting in the exhaust gas. The fuel-air mixture comprises the preferably liquid or gaseous fuel and the air from the intake tract 4. The internal combustion engine 1 has a fuel tank 13, shown particularly schematically in Fig. 1 and simply referred to as a tank, in which the fuel can be or is held at least temporarily. The internal combustion engine 1 has a tank venting device 14, which is provided or designed to vent the fuel tank 13 and is also referred to as the first venting device.The tank ventilation device 14 has a first suction jet pump 15, which is also referred to as a first jet pump. At least a first portion of the air from the intake tract can be supplied to the first suction jet pump 15 for venting the fuel tank 13, so that for venting the fuel tank 13 by means of the first suction jet pump 15, using the air supplied to the first suction jet pump 15 as the first propellant medium for the first suction jet pump 15, a first gas can be sucked in as the first suction medium from the fuel tank 13 and thus pumped out of the fuel tank 13. The tank ventilation device 14 has a first mixture line 16 through which a first mixture comprising the first suction medium and the first propellant medium can flow. In Fig.1, an arrow 17 indicates a third flow direction in which the first mixture flows through the mixture line 16 in order to thereby discharge the first mixture from the suction jet pump 15.

[0025] The internal combustion engine 1 further comprises a crankcase ventilation device 18, which is also referred to as a second ventilation device. The crankcase ventilation device 18 comprises a second suction jet pump 19, also referred to as a second jet pump, to which at least a second portion of the air from the intake tract 4 can be supplied for venting the crankcase 2. Such that, for venting the crankcase 2, a second gas can be sucked in as a second suction medium from the crankcase 2 and thus pumped out of the crankcase 2 by means of the second suction jet pump 19, using the air supplied to the second suction jet pump 19 as a second propulsion medium for the second suction jet pump 19. The crankcase ventilation device 18 has a second mixture line 20, through which a second mixture comprising the second suction medium and the second propulsion medium can flow. In Fig.1, an arrow 21 indicates a fourth flow direction in which the second mixture flows through the second mixture line 20 in order to discharge the second mixture from the suction jet pump 19, i.e., to carry it away. A fifth flow direction opposite to the fourth flow direction is illustrated by an arrow 22. The second mixture can be introduced into the inlet tract 4 at an inlet point E via or by means of the second mixture line 20. For this purpose, the mixture line 20 is fluidically connected to the inlet tract 4 at the inlet point E. The first mixture line 16 is fluidically connected to the second mixture line 20 at a connection point V which, with respect to the fourth flow direction illustrated by the arrow 21, is arranged upstream of the inlet point E and downstream of the second suction jet pump 19, in particular in the second mixture line 20.At the connection point V, the first mixture can be discharged from the first mixture line 16 and introduced into the second mixture line 20. From Fig. 1 it can be seen that the second mixture line 20 has a first length range L1 which extends, in particular continuously and thus without interruption, from the connection point V to the introduction point E. L2 designates a second length range of the mixture line 20. The second length range L2 extends from the connection point V, in particular continuously and thus without interruption, to the suction jet pump 19 and vice versa, so that with respect to the fourth flow direction illustrated by the arrow 21, the second length range L2 is arranged upstream of the first length range L1. The length ranges L1 and L2 are fluidically connected to one another, wherein, for example, the length range L2 immediately and thus directly merges into the length range L1 and vice versa.

[0026] The crankcase ventilation system 18 also includes an oil separator 23, which is preferably designed as a passive oil separator, in particular a purely passive oil separator, by means of which any oil contained in the second gas can be passively separated from the gas, in particular in pure form. In the present case, the suction jet pump 19, the mixture line 20, and also the oil separator 23 are components of a full-load crankcase ventilation system 24, by means of which the crankcase 2 is to be or is to be vented at full load, i.e., during full-load operation of the internal combustion engine 1. The suction jet pump 19, the mixture line 20 and, in this case, also the oil separator 23 are thus in a full-load path 25 of the crankcase ventilation device 18, in particular the full-load crankcase ventilation 24, wherein the second gas can be or is discharged from the crankcase 2 via the full-load path 25, in particular during full-load operation of the internal combustion engine 1.If, particularly during full-load operation of the internal combustion engine 1, the crankcase 2 is vented via the full-load path 25 by means of the suction jet pump 19, the second gas flows from the crankcase 2 in the fourth flow direction, illustrated by the arrow 21, through the full-load path 25 and thus through the oil separator 23, the suction jet pump 19, and the mixture line 20. With respect to the fourth flow direction, the oil separator 23 is arranged upstream of the suction jet pump 19, which is arranged, for example, upstream of at least part of the mixture line 20. By means of the suction jet pump 19, a particularly advantageous pressure ratio can be realized, by means of which the crankcase 2 can be vented particularly advantageously and, in particular, a particularly high separation efficiency of the oil separator 23 can be realized.In addition, for example during partial load, i.e. during partial load operation of the internal combustion engine 1, an advantageous purge air flow can occur, which is formed by air from the intake tract 4. This purge air flow is explained in more detail below. In the exemplary embodiment shown in Fig. 1, the internal combustion engine 1 has a check valve 26 which, with respect to the fourth flow direction illustrated by the arrow 21, is arranged downstream of the connection point V in the second mixture line 20 and automatically opens in the direction of the intake tract 4 and closes in the direction of the connection point V. As a result, for example, the second mixture can flow through the mixture line 20 and the check valve 26 in the fourth flow direction and thus flow into the intake tract 4 at the inlet point E.However, in the fifth flow direction illustrated by arrow 22, which is opposite to the fourth flow direction, the check valve 26 closes automatically and thus blocks the mixture line 20 for a flow coming from the inlet tract 4 and flowing in the direction of the connection point V, so that, for example, a backflow of air from the inlet tract 4 to the connection point V via the check valve 26 can be prevented. For example, the check valve 26 is arranged upstream of the inlet point E and downstream of the connection point V with respect to the fourth flow direction illustrated by arrow 21, or the check valve 26 is arranged at the inlet point E and thus downstream of the connection point V.

[0027] The inlet tract 4 has a supply point VS at which both the first part of the air flowing through the inlet tract 4 can be branched off from the inlet tract 4 and supplied as the first driving medium to the first suction jet pump 15 and the second part of the air flowing through the inlet tract 4 can be branched off from the inlet tract 4 and supplied as the second driving medium to the second suction jet pump 19.

[0028] A throttle valve 27 is arranged in the intake tract 4, by means of which throttle valve 27 the amount of air flowing through the intake tract 4 to be supplied to the combustion chambers of the internal combustion engine 1 can be adjusted. Furthermore, a charge air cooler 28 is arranged in the intake tract 4, which is located downstream of the compressor 10 and downstream of the throttle valve 27. The air compressed and thereby heated by the compressor 10 can be cooled by the charge air cooler 28. In the embodiment shown in Fig. 1, the supply point VS is arranged upstream of the throttle valve 27 and downstream of the compressor 10, and in this case downstream of the charge air cooler 28, in the flow direction of the air flowing through the intake tract 4 and towards the combustion chambers. The respective propellant can thus be air originating from the intake tract 4, compressed by the compressor 10.The internal combustion engine 1 has a first supply line 29, which is fluidically connected to the intake tract 4 at a first branching point AZ1. By means of the supply line 29, at least a portion of the air flowing through the intake tract 4 is branched off from the intake tract 4 at the first branching point AZ1 and introduced into the first supply line 29, wherein the portion of the air flowing through the intake tract 4 branched off from the intake tract 4 at the branching point AZ1 and introduced into the supply line 29 is also referred to as supply air. The internal combustion engine 1 also has a second supply line 30, which is fluidically connected to the first supply line 29 at a second branching point AZ2.In the flow direction of the supply air flowing through the supply line 29 and from the branch point AZ1 toward the suction jet pump 15, the branch point AZ2 is located downstream of the branch point AZ1 and upstream of the suction jet pump 15. By means of the supply line 30, a first portion of the supply air is left in the supply line 29, and a second portion of the supply air is branched off from the supply line 29 at the second branch point AZ2 and introduced into the supply line 30 and guided to the suction jet pump 19 by means of the supply line 30, so that the second portion of the supply air branched off from the supply line 29 at the branch point AZ2 is used as the second propulsion medium for the suction jet pump 19. Thus, the second portion of the supply air is the aforementioned second portion of the air from the inlet tract 4, used as the second propulsion medium.The first portion of the supply air left in the supply line 29, i.e., the remaining first portion, is guided to the suction jet pump 15 via the supply line 29 and used as the first propulsion medium for the suction jet pump 15. Thus, the first portion of the supply air is the aforementioned first portion of the air from the inlet tract 4 used as the first propulsion medium. It can be seen that the supply point VS is the first branch point AZ, so that both suction jet pumps 15 and 19 can be supplied with the propulsion media via the supply point VS or branch point AZ1 common to the suction jet pumps 15 and 19.

[0029] The supply line 29 is also referred to, for example, as the first drive line, since the suction jet pump 15 is supplied with the first drive medium via the supply line 29. The second supply line 30 is also referred to, for example, as the second drive line, since the suction jet pump 19 can be or is supplied with the second drive medium via the supply line 30. In Fig. 1, a first suction line is designated 31. The first suction line 31 is, for example, a component of the tank ventilation device 14. The first suction medium from the fuel tank 13 can be supplied to the suction jet pump 15 via the first suction line 31, in particular via a tank ventilation valve 32 of the tank ventilation device 14. For example, the tank ventilation valve 32 is arranged in the suction line 31.For example, a pressure sensor 33 of the tank ventilation device 14 can be arranged in the suction line 31, in particular such that, in the flow direction of the first suction medium flowing through the suction line 31 and in particular from the fuel tank 13 to the suction jet pump 15, the pressure sensor 33 is arranged upstream of the suction jet pump 15 and downstream of the fuel tank 13. A pressure prevailing in the suction line 31 can be detected by means of the pressure sensor 33. For example, a pressure sensor 34, shown particularly schematically in Fig. 1, is arranged in the supply line 30, in particular such that, in the flow direction of the second propellant medium flowing through the supply line 30 and thereby towards the suction jet pump 19, the pressure sensor 34 is arranged upstream of the suction jet pump 19 and in particular downstream of the branch point AZ2.The pressure sensor 34 can be used to detect the pressure prevailing in the supply line 30. The pressure sensor 34 is preferably arranged particularly close to the suction jet pump 19.

[0030] In the embodiment shown in Fig. 1, the crankcase ventilation device 18 has a partial-load crankcase ventilation 35, provided in particular in addition to the full-load crankcase ventilation 24, by means of which the crankcase 2 is or can be vented during partial load, i.e., during partial load operation of the internal combustion engine 1. The partial-load crankcase ventilation 35 has a partial-load path 36, via which the crankcase 2 is vented during partial load operation of the internal combustion engine 1.

[0031] The crankcase ventilation device 18 has a second suction line 46, via which the second gas from the crankcase 2 can be supplied to the suction jet pump 19. In other words, the suction jet pump 19 sucks in the second gas from the crankcase 2 via the second suction line 46, in particular when the crankcase 2 is vented by means of the crankcase ventilation device 18, in particular by means of the full-load crankcase ventilation 24, in particular during full-load operation of the internal combustion engine 1. If the crankcase 2 is vented by means of the full-load crankcase ventilation 24 and thereby during full-load operation of the internal combustion engine 1, the second suction medium flows in the fourth flow direction illustrated by the arrow 21 through the full-load path 25 and thus through the suction line 46.With respect to the second flow direction of the second gas, illustrated by arrow 21, the oil separator 23 is arranged upstream of the suction jet pump 19 and, for example, downstream of the crankcase 2 in the suction line 46, so that the second suction medium flows through the oil separator 23 on its way from the crankcase 2 to the suction jet pump 19. The oil separator 23 is also referred to as a full-load separator (FLA). A first return line is designated 37. Via the first return line 37, the oil separated from the second gas by the oil separator 23 can be guided, for example, back into the crankcase 2 and / or into an oil pan of the internal combustion engine 1.

[0032] It can be seen that the full-load path 25 comprises the suction line 46 and thus the oil separator 23, the suction jet pump 19, and the mixture line 20. The part-load crankcase ventilation 35 has a vent line 39, so that the part-load path 36 comprises the vent line 39. The second gas or a third gas can be discharged from the crankcase 2 via the vent line 39, particularly during part-load operation of the internal combustion engine 1, wherein a further oil separator 38, provided in particular in addition to the oil separator 23, is arranged in the vent line 39. The oil separator 38 is thus a part-load separator (TLA), by means of which any oil contained in the second or third gas flowing through the vent line 39 or the part-load path 36, respectively, is separated, particularly during part-load operation of the internal combustion engine 1.A second return line 40 is provided, by means of which the oil separated by the oil separator 38 can be discharged from the oil separator 38 and, for example, guided, in particular returned, into the crankcase 2 and / or into the oil pan and / or into a cylinder head of the internal combustion engine 1. Downstream of the oil separator 38, the vent line 39 or the partial load path 36 can introduce the purified gas, in particular via check valves 41, into the intake tract 4 and / or directly into the combustion chambers, in particular at a location downstream of the throttle valve 27.It can be seen that the intake line 46 and the vent line 39, and thus the full-load path 25 and the partial-load path 36, have a common line section 42, through which gas is discharged from the crankcase 2 both when the crankcase 2 is vented by means of the full-load crankcase ventilation 24 during full-load operation of the internal combustion engine 1 and when the crankcase 2 is vented by means of the partial-load crankcase ventilation 35 during partial-load operation of the internal combustion engine 1. The aforementioned purge air flow is described below.Particularly during partial load, i.e., partial load operation of the internal combustion engine 1, the purge air flow can develop or be established, which is formed by air from the intake tract 4 and flows or is guided from the supply point VS or from the branch point AZ1 via the supply line 29, the suction jet pump 15, the mixture line 16, and the length range L2 to the suction jet pump 19. The purge air flow is thus discharged from the mixture line 16 at the connection point V and introduced into the length range L2 and can flow through the length range L2 in the fifth flow direction, illustrated by the arrow 22, opposite the fourth flow direction, and thus flow to the suction jet pump 19.

[0033] In Fig. 1, an arrow 43 illustrates a sixth flow direction in which the second suction medium flows through the suction line 46 and the oil separator 23 on its way from the crankcase 2 to the suction jet pump 19. A seventh flow direction opposite to the sixth flow direction is illustrated by an arrow 44. The aforementioned purge air flow can flow from the suction jet pump 19 in the seventh flow direction illustrated by the arrow 44 through at least a portion of the suction line 46 and thus flow via the portion of the suction line 46 to the oil separator 23. From the oil separator 23, for example, the purge air flow can flow through the return line 37 and flow into the crankcase 2 via the return line 37.It can be seen that the purge air flow can be introduced or is introduced into the crankcase 2 via the supply line 29, the suction jet pump 15, the mixture line 16, the length range L2, the suction jet pump 19, at least part of the suction line 46 and the oil separator 23, as well as, in this case, the return line 37, whereby the crankcase 2 can be purged and thus ventilated. Thus, for example, an additional purge air line for purging the crankcase 2 can be dispensed with.

[0034] In the exemplary embodiment shown in Fig. 1, however, an additional purge air line is shown as an example and designated 45. The purge air line 45 is fluidly connected to the intake tract 4 at a first purge air point LS1 and fluidly connected to the crankcase 2 at a second purge air point LS2. In the exemplary embodiment shown in Fig. 1, the purge air point LS1 is arranged upstream of the compressor 10 in the flow direction of the air flowing through the intake tract 4 and towards the combustion chambers and, in this case, downstream of the air filter 6 and, in this case, also upstream of the introduction point E. For example, a check valve 47 is arranged in the purge air line 45. By means of the purge air line 45, at least a portion of the air flowing through the intake tract 4 can be branched off from the intake tract 4 at the purge air point LS1 and introduced into the purge air line 45 as purge air.The purge air introduced into the purge air line 45 can be introduced into the crankcase 2 via the purge air line 45 and the check valve 47, whereby the crankcase 2 can be ventilated, and thus purged. Thus, it is preferably provided that the check valve 47 opens, in particular automatically, toward the crankcase 2 and closes, in particular automatically, in the opposite direction, thus toward the purge air point LS1.

[0035] In principle, it would be conceivable that the supply point VS or the branch point AZ1 is arranged in the intake tract 4 downstream of the throttle valve 27 and in particular upstream of the combustion chambers.

[0036] List of reference symbols

[0037] internal combustion engine

[0038] crankcase

[0039] cylinder

[0040] Inlet tract

[0041] Arrow

[0042] Air filter

[0043] exhaust tract

[0044] Arrow

[0045] exhaust gas turbocharger

[0046] compressor

[0047] turbine

[0048] Wave

[0049] fuel tank

[0050] Tank ventilation device first suction jet pump first mixture line

[0051] Arrow

[0052] Crankcase ventilation device second suction jet pump second mixture line

[0053] Arrow

[0054] Arrow

[0055] Oil separator

[0056] Full-load crankcase ventilation

[0057] Full load path

[0058] check valve

[0059] throttle

[0060] Intercooler first supply line second supply line first suction line

[0061] Tank vent valve

[0062] pressure sensor

[0063] Pressure sensor 35 partial load crankcase ventilation

[0064] 36 Partial load path

[0065] 37 Return line

[0066] 38 oil separators

[0067] 39 Ventilation line

[0068] 40 Return line

[0069] 41 Check valve

[0070] 42 line section

[0071] 43 Arrow

[0072] 44 Arrow

[0073] 45 Purge air line

[0074] 46 second suction line

[0075] 47 Check valve

[0076] E Discharge point

[0077] V Connection point

[0078] L1 first length range

[0079] L2 second length range

[0080] LS1 purge air point

[0081] LS2 purge air point

[0082] AZ1 junction

[0083] AZ2 junction point VS supply point

Claims

Patent claims 1. Internal combustion engine (1) for a motor vehicle, comprising: - a crankcase (2); - an inlet tract (4) through which air can flow; - a tank venting device (14) provided for venting a fuel tank (13), which has: o a first suction jet pump (15), to which at least a first portion of the air from the inlet tract (14) can be supplied for venting the fuel tank (13), so that for venting the fuel tank (13) by means of the first suction jet pump (15), using the air supplied to the first suction jet pump (15) as the first propulsion medium for the first suction jet pump (15), a first gas can be sucked in from the fuel tank (13) as the first suction medium; and o a first mixture line (16) through which a first mixture comprising the first suction medium and the first propulsion medium can flow; and - a crankcase ventilation device (18) comprising: o a second suction jet pump (19) to which at least a second portion of the air from the inlet tract (4) can be supplied for venting the crankcase (2), so that a second gas can be sucked in as a second suction medium from the crankcase (2) for venting the crankcase (2) by means of the second suction jet pump (19) using the air supplied to the second suction jet pump as a second propulsion medium for the second suction jet pump (19);and o a second mixture line (20) through which a second mixture comprising the second suction medium and the second propellant medium can flow, via which the second mixture can be introduced into the inlet tract (4) at an inlet point (E), wherein the first mixture line (16) is fluidically connected to the second mixture line (20) at a connection point (V) arranged downstream of the second suction jet pump (19) and upstream of the inlet point (E), at which connection point the first mixture can be introduced from the first mixture line (16) into the second mixture line (20); 2. Internal combustion engine (1) according to claim 1, characterized by a check valve (26) which is arranged in the second mixture line (20) downstream of the connection point (V) and opens in the direction of the inlet tract (4) and closes in the direction of the connection point (V).

3. Internal combustion engine (1) according to claim 1 or 2, characterized in that the inlet tract (4) has a supply point (VS) at which: - the first part of the air flowing through the inlet tract (4) can be branched off from the inlet tract (4) and fed as the first driving medium to the first suction jet pump (15); and / or - the second part of the air flowing through the inlet tract (4) can be branched off from the inlet tract (4) and fed as the second driving medium to the second suction jet pump (19).

4. Internal combustion engine (1) according to claim 3, characterized in that the supply point (VS) is arranged downstream of a throttle valve (27) arranged in the intake tract (4).

5. Internal combustion engine (1) according to claim 3, characterized in that the supply point (VS) is arranged upstream of a throttle valve (27) arranged in the intake tract (4).

6. Internal combustion engine (1) according to one of the preceding claims, characterized by: - a first supply line (29) fluidically connected to the first suction jet pump (15) and fluidically connected to the inlet tract (4) at a first branching point (AZ1), by means of which at least a portion of the air flowing through the inlet tract (4) can be branched off from the inlet tract (4) at the first branching point (AZ1) and introduced into the first supply line (29) as supply air; and - a second supply line (30) fluidically connected to the first supply line (29) at a second branching point (AZ1) arranged downstream of the first branching point (AZ1) and upstream of the first suction jet pump (15), by means of which second supply line (30) a second part of the supply air can be branched off from the first supply line (29) at the second branching point (AZ2) while leaving a first part of the supply air in the first supply line (29) and can be introduced as the second propellant into the second supply line (30), by means of which the second propellant can be supplied to the second suction jet pump (19), wherein the first part of the supply air left in the first supply line (29) can be supplied as the first propellant to the first suction jet pump (15) by means of the first supply line (29).

7. Internal combustion engine (1) according to claim 5 in its reference to one of claims 3 to 5, characterized in that the supply point (VS) is the first branch point (AZ1) and thus a supply point (VS) common to the suction jet pumps (15, 19), via which the suction jet pumps (15, 19) can be supplied with the driving media from the inlet tract (4).

8. Internal combustion engine (1) according to claim 6 or 7, characterized in that a pressure sensor (34) is arranged in the second supply line (30) upstream of the second suction jet pump (19) and downstream of the second branch point (AZ2), by means of which a pressure prevailing in the second supply line (30) can be detected.

9. Internal combustion engine (1) for a motor vehicle, comprising a crankcase (2), an inlet tract (4) through which air can flow, a throttle valve (27) arranged in the inlet tract (4), by means of which a quantity of air to be supplied to at least one combustion chamber of the internal combustion engine (1) can be adjusted, and a crankcase ventilation device (18) which has a suction jet pump (19) to which at least part of the air from the inlet tract (4) can be supplied for venting the crankcase (2), so that for venting the crankcase (2) by means of the suction jet pump (19) using the air supplied to the suction jet pump (19) as the driving medium for the suction jet pump (19) a gas can be sucked in from the crankcase (2) as the suction medium, characterized in that a supply point (VS), at which at least part of the air can be branched off as the driving medium from the inlet tract (4), is arranged downstream of the throttle valve (27).

10. Motor vehicle with an internal combustion engine (1) according to one of the preceding claims.

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