DE102020006562A1 - Internal combustion engine for a motor vehicle, in particular for a motor vehicle, and motor vehicle - Google Patents

Abstract

The invention relates to an internal combustion engine (10), with an exhaust gas tract (18) through which exhaust gas from a combustion chamber (16a) of the internal combustion engine (10) can flow, with an intake duct (20) through which fresh air can flow, with an exhaust gas turbocharger (22) which has an in the exhaust tract (18) arranged turbine wheel (30) and a compressor wheel (26) for compressing the fresh air, with a secondary air line (38) through which secondary air can flow, by means of which the secondary air can be introduced into the exhaust tract (18), and with a valve element ( 40), by means of which a quantity of the secondary air flowing through the secondary air line (38) can be adjusted. The valve element (40) is designed as a combination valve, via which the secondary air line (38) is fluidly connected or can be connected to the intake tract (20) at a branch point (A) arranged downstream of the compressor wheel (26), at which the fresh air from the The intake tract (20) can be branched off and introduced into the secondary air line (38) via the valve element (40). The turbine (26) is designed as a segment turbine.

Description

The invention relates to an internal combustion engine for a motor vehicle, in particular for a motor vehicle, according to the preamble of patent claim 1. The invention also relates to a motor vehicle.

the DE 103 48 131 A1 discloses an internal combustion engine with an intake tract for the intake air and an exhaust system for the combustion products of the internal combustion engine, as well as with a secondary air injection into the exhaust system for after-treatment of the combustion products and a measuring device for determining the secondary air delivery rate.

The object of the present invention is to create an internal combustion engine for a motor vehicle and a motor vehicle with such an internal combustion engine, so that a particularly advantageous secondary air injection can be implemented in a particularly cost-effective and weight-efficient manner.

This object is achieved by an internal combustion engine having the features of patent claim 1 and by a motor vehicle having the features of patent claim 10 . Advantageous configurations with expedient developments of the invention are specified in the remaining claims.

A first aspect of the invention relates to an internal combustion engine, also referred to as an internal combustion engine and preferably designed as a reciprocating piston engine, for a motor vehicle, in particular for a motor vehicle preferably designed as a passenger car or else as a commercial vehicle. This means that the motor vehicle in its fully manufactured state includes the internal combustion engine and can be driven by the internal combustion engine. The internal combustion engine has at least one combustion chamber, which is also referred to as the first combustion chamber. In a fired operation of the internal combustion engine, combustion processes take place in the combustion chamber, during which a respective fuel-air mixture is burned. This results in exhaust gas from the internal combustion engine.

The internal combustion engine has an exhaust gas tract through which the exhaust gas from the at least one combustion chamber can flow and in which an exhaust gas aftertreatment device for aftertreatment of the exhaust gas can be arranged. Furthermore, the internal combustion engine includes an intake tract, also referred to as the intake tract, through which at least fresh air can flow. This means that at least fresh air can flow through the intake tract. In particular, a mixture can flow through the intake tract, wherein the mixture can include the fresh air and at least one other component such as recirculated exhaust gas and/or, in particular, unburned fuel. The fresh air flowing through the intake tract and the aforementioned, preferably liquid, fuel form the aforementioned fuel-air mixture, which can be burned in the at least one combustion chamber. The fresh air is routed to and into the combustion chamber by means of the intake tract.

The internal combustion engine includes an exhaust gas turbocharger, which includes a turbine with a turbine wheel that is arranged in the exhaust gas tract and can be driven by the exhaust gas. The exhaust gas turbocharger also includes a compressor with a compressor wheel arranged in the intake tract for compressing the fresh air to be introduced into the combustion chamber. The compressed fresh air is also referred to as charge air, since the compression of the fresh air is also referred to as charging. The at least one combustion chamber can be supplied with the compressed fresh air (charge air). In other words, the charge air can be introduced into the at least one combustion chamber.

The internal combustion engine also has at least one secondary air line through which secondary air can flow, by means of which the secondary air flowing through the secondary air line can be introduced into the exhaust tract, in particular bypassing all combustion chambers of the internal combustion engine. The preferably provided feature that the secondary air flowing through the secondary air line can be introduced into the exhaust tract by means of the secondary air line, bypassing all combustion chambers of the internal combustion engine, means that the secondary air flowing through the secondary air line preferably bypasses all combustion chambers of the internal combustion engine and thus not through the combustion chambers of the Internal combustion engine can flow through, that is, does not flow through any combustion chamber of the internal combustion engine. By means of the secondary air introduced into the exhaust tract, for example, the aforementioned exhaust gas aftertreatment device can be heated particularly strongly and in a short time, in particular because the secondary air introduced into the exhaust tract, for example with unburned and therefore still combustible fuel fractions contained in the exhaust gas, forms a secondary air/fuel fraction mixture forms, which can be burned in the exhaust tract with the release of heat. As a result, or by means of the aforementioned heat, the exhaust aftertreatment treatment device is heated and thereby also brought to its light-off temperature, for example. The mixture of secondary air and fuel is burned, for example, by the secondary air and fuel mixture being ignited by means of an ignition device, such as a glow plug, which is arranged in the exhaust gas tract and can be operated electrically, for example, and is thereby burned, or the secondary air and fuel mixture is ignited at one hot components arranged in the exhaust gas tract, in particular the exhaust gas aftertreatment device, as a result of which the mixture of secondary air and fuel components is burned. The component is, for example, a catalytic converter, in particular an oxidation catalytic converter, of the exhaust gas aftertreatment device.

The internal combustion engine also has a valve element, by means of which a quantity of the secondary air flowing through the secondary air line can be adjusted. This can be understood to mean, for example, that a flow cross section through which the secondary air can flow can be adjusted by means of the valve element, as a result of which the quantity of secondary air flowing through the secondary air can be adjusted. In particular, the feature that the quantity of secondary air flowing through the secondary air line can be adjusted by means of the valve element means that the valve element can be adjusted or switched between at least two states. In a first of the states of the valve element, for example, a first value is set for the quantity of secondary air flowing through the secondary air line, with the first value being able to be 0 - possibly except for any technically caused leaks - so that, for example, the first state is a closed state in which the valve element the secondary air line - except for the previously mentioned, any, technically caused leaks - is blocked by the valve element. Then no secondary air can flow through the secondary air line. In the second state, the valve element sets a second value for the quantity of secondary air flowing through the secondary air line that is greater than 0 and the first value, for example, so that the valve element releases the secondary air line in the second state. Thus, the second state is a release state, for example, in which secondary air can flow through the secondary air line. To put it another way, for example in the second state the quantity of secondary air flowing through the secondary air line is greater than in the first state. Furthermore, it is conceivable that the valve element can be adjusted into at least one or more further states in which the valve element generates a value that is different from the first value and from the second value and is greater than 9 for the quantities of secondary air flowing through the secondary air line or other values of the quantity of secondary air flowing through the secondary air line that are different from the first value and from the second value, preferably greater than 0, are set. The introduction of the secondary air into the exhaust tract is also referred to as secondary air introduction, secondary air supply or secondary air injection.

In order to be able to implement the secondary air injection in a way that is particularly economical in terms of cost, weight and installation space, it is provided according to the invention that the valve element is designed as a combination valve. The combination valve is also referred to as a combination valve. The secondary air line is fluidically connected or can be connected to the intake tract at a branch point arranged downstream of the compressor wheel via the combination valve, also referred to as a combination valve, so that at least part of the fresh air, in particular conveyed and/or compressed by means of the compressor wheel, can be branched off from the intake tract at the branch point , can be introduced via the valve element into the secondary air line and can be introduced as the secondary air into the exhaust tract by means of the secondary air line. In other words, at least the aforementioned part of the fresh air can be branched off from the intake tract at the branching point, that is to say it can be discharged from the intake tract. The branched off part of the fresh air is fed into the secondary air line via the valve element. The part introduced into the secondary air line or the fresh air introduced into the secondary air line via the combination valve can be introduced as the secondary air by means of the secondary air line to and into the exhaust tract, so that the branched off part on its way from the branching point to the exhaust tract the valve element (combi valve) flows through.

The branching point is arranged, for example, in the direction of flow in the fresh air flowing through the intake tract upstream of a throttle valve arranged in the intake tract, by means of which a quantity of fresh air to be introduced into the at least one combustion chamber and thus to be supplied to the combustion chamber can be adjusted. If, for example, the initially opened throttle valve is closed, then at least the above-mentioned part of the fresh air compressed by means of the compressor wheel, which is initially arranged between the compressor wheel and the throttle valve that is then closed, can be branched off at the branching point from the intake tract and via the valve element into the secondary air line and into the Exhaust tract are performed. As a result, an excessive braking of the compressor wheel caused by the compressed fresh air initially located between the compressor wheel and the throttle valve can be avoided. The invention thus combines, so to speak, an overrun air recirculation system with a secondary air system. Here, according to the invention, the valve element has a dual function, so that the valve element is designed as the aforementioned combination valve. On the one hand, the valve element is used to adjust the quantity of secondary air flowing through the secondary air line and to be introduced into the exhaust gas tract, so that the valve element is used as a kind of secondary air valve. On the other hand, the valve element is used as a diverter valve (SUV) in order to divert at least the above-mentioned part of the fresh air from the intake tract via the diverter valve and introduce it into the secondary air line and via this into the exhaust tract. As a result, for example, an additional, separate overrun air recirculation system can be avoided, so that the number of parts, the weight, the installation space requirement and the costs of the internal combustion engine can be kept within a particularly low range.

The configuration of the valve element as a combination valve also makes it possible to use the compressor wheel, for example, to convey the secondary air by means of the compressor wheel, in particular to convey it through the secondary air line. The compressor wheel can thus be used as a secondary air pump, which is also referred to simply as an air pump, with the secondary air being conveyed, for example, into the secondary air line and/or being conveyed through the secondary air line, by means of the secondary air pump. As a result, an additional, separate conveying device for conveying the secondary air can be avoided, so that the costs, the number of parts, the weight and the space requirement of the internal combustion engine can be kept within a particularly low range. The use of the compressor wheel as a secondary air pump is also advantageous in that a particularly high pressure drop can be created or a particularly large mass and/or volume flow of the secondary air can be realized by means of the compressor wheel. This means in particular that a particularly large amount of oxygen, also referred to as the amount of oxygen, contained in the secondary air conveyed by means of the compressor wheel, can be introduced into the exhaust gas tract, so that the exhaust gas aftertreatment device, for example, can be heated particularly effectively and efficiently.

Furthermore, it is provided according to the invention that the turbine is designed as a segment turbine. The turbine thus has at least or exactly two segments through which the exhaust gas of the internal combustion engine can flow, which are at least partially fluidically separated from one another and arranged one behind the other or consecutively in the circumferential direction of the turbine wheel over its circumference, i.e. connected in series. The turbine includes, for example, a turbine housing in which the turbine wheel is rotatably accommodated. The turbine housing delimits a receiving space in which the turbine wheel is rotatably received. The segments of the segment turbine, which are designed, for example, as segment spirals and thus as spiral ducts, open into the receiving space in particular via respective outflow cross-sections through which the exhaust gas can flow. In the case of the segmented turbine, it is provided that the segments in the circumferential direction of the turbine wheel open one behind the other or one after the other over its circumference into the receiving space, so that the outflow cross sections are not arranged next to one another or one behind the other, or not only in the axial direction of the turbine or the turbine wheel, but In the segment turbine, the outflow cross sections are arranged or connected in succession or one behind the other in the circumferential direction of the turbine wheel over its circumference. Due to the design of the turbine as a multi-segment turbine, the overrun air system and the secondary air system can be combined or combined particularly well as described above, so that the number of parts, the weight, the costs and the space requirement can be kept particularly low.

In order to be able to keep the number of parts, the costs, the weight and the installation space requirement to a particularly low level, it is provided in a further embodiment of the invention that the valve element is also designed or can be operated as a non-return valve which blocks in the direction of the branch point and in opens in the opposite direction. This means in particular that the valve element prevents the secondary air from flowing in the direction of the branch point and thus in a first flow direction through the valve element, since the valve element closes in the first flow direction. However, the valve element opens in a second flow direction opposite to the first flow direction, pointing away from the branching point and, for example, towards the secondary air line, so that the secondary air can flow along the second flow direction from the branching point to the secondary air line and thereby through the valve element. As a result, the use of a further, separate and additional check valve can be avoided. Thus, it is preferably provided that the combination valve has the functions a check valve or check valves, a diverter valve and a secondary air pump or a secondary air valve. Thus, the valve element may even have a triple function.

In order to be able to convey a particularly large amount of secondary air and introduce it into the intake tract in a particularly cost-effective, weight-saving and space-saving manner, a further embodiment of the invention provides for an electrical machine to be assigned to the compressor wheel, by means of which the compressor wheel is electrically, i.e can be driven using electrical energy. For example, the exhaust gas turbocharger is designed as an electrically assisted exhaust gas turbocharger (euATL), so that at least the compressor wheel and preferably also the turbine wheel can be driven, in particular via the shaft, by means of the electric machine. With the help of the electric machine, at least the compressor wheel can also be driven advantageously, so that the secondary air can also be advantageously conveyed by means of the compressor wheel when no or only a small mass flow of the exhaust gas is available for driving the turbine wheel and thus the compressor wheel. This has proven to be particularly advantageous when the motor vehicle is designed as a hybrid vehicle, because such a hybrid vehicle can have operating states extending over long periods of time in which the internal combustion engine is deactivated and therefore does not provide any exhaust gas resulting from combustion processes.

A further embodiment is characterized in that the internal combustion engine has at least or exactly four cylinders. The cylinders are arranged next to one another along a straight line, for example, and are therefore arranged in series. A first of the cylinders partially delimits the at least one combustion chamber, the at least one combustion chamber--as described above--also being referred to as the first combustion chamber. The first cylinder and thus the first combustion chamber are fluidically connected to a first exhaust gas line of the exhaust tract through which exhaust gas from the first cylinder or the first combustion chamber can flow, so that the exhaust gas can flow out of the first combustion chamber and into the first exhaust gas line. A second of the cylinders partially delimits a second combustion chamber of the internal combustion engine, the second cylinder being in particular directly adjacent to the first cylinder. The feature that the second cylinder is adjacent to the first cylinder means that, in particular along the aforementioned imaginary straight line between the first cylinder and the second cylinder, no other cylinder of the internal combustion engine that delimits another combustion chamber is arranged . The second cylinder and thus the second combustion chamber are fluidically connected to a second exhaust gas line of the exhaust tract through which exhaust gas from the second cylinder or from the second combustion chamber can flow and which is at least partially fluidically separated from the first exhaust gas line, so that the gas from the second cylinder or the second combustion chamber outflowing exhaust gas flows into the second exhaust pipe and flows through the second exhaust pipe.

A third of the cylinders partially delimits a third combustion chamber of the internal combustion engine, the third cylinder being particularly directly adjacent to the second cylinder, particularly along the aforementioned straight line. The third cylinder and thus the third combustion chamber are fluidically connected to a third exhaust line of the exhaust tract through which exhaust gas from the third cylinder or the third combustion chamber can flow and which is at least partially fluidically separated from the first exhaust line and the second exhaust line, so that the from the third Combustion chamber or exhaust gas flowing out of the third cylinder flows into the third exhaust pipe and flows through the third exhaust pipe. The fourth cylinder partially delimits a fourth combustion chamber of the internal combustion engine, the cylinder being adjacent to the third cylinder, in particular along the imaginary straight line mentioned above. In addition, the fourth cylinder and thus the fourth combustion chamber are fluidically connected to a fourth exhaust line of the exhaust tract through which exhaust gas from the fourth cylinder or from the fourth combustion chamber can flow and which is at least partially fluidically separated from the first exhaust line, the second exhaust line and the third exhaust line , so that the exhaust gas flowing out of the fourth cylinder or the fourth combustion chamber flows into the fourth exhaust pipe and flows through the fourth exhaust pipe.

Three alternative sub-executions are now possible. In a first of the sub-designs, it is provided that, with regard to the exhaust lines, only the second exhaust line of the second cylinder and the third exhaust line of the third cylinder each have at least or exactly one inlet point at which the secondary air flowing through the secondary air line is fed into the second exhaust line and into the third exhaust pipe can be introduced.

In a second of the sub-embodiments, it is provided that, based on the four exhaust lines, exclusively the first exhaust line and the fourth exhaust line each at least or exactly have an introduction point at which the secondary air flowing through the secondary air line can be introduced into the first exhaust gas line and into the fourth exhaust gas line.

In a third of the sub-embodiments, it is provided that the internal combustion engine comprises a second secondary air line, which is at least partially fluidically separated from the secondary air line and through which additional secondary air can flow. It is conceivable that the additional secondary air, which flows through the second secondary air line, comes from the intake tract. Thus, the previous and following statements on the first secondary air can also be applied to the second secondary air and vice versa. As will be explained in more detail below, in the third sub-embodiment, for example, the additional secondary air flowing through the second secondary air line can be introduced into the exhaust tract by means of the second secondary air line, preferably bypassing the or all combustion chambers of the internal combustion engine, so that the additional secondary air flowing through the second secondary air line does not flow through any combustion chamber of the internal combustion engine.

In the third sub-embodiment, it is preferably provided that the first exhaust pipe has at least or exactly one first inlet point, the second exhaust pipe has at least or exactly one second inlet point, the third exhaust pipe has at least or exactly one third inlet point and the fourth exhaust pipe has at least or exactly one fourth inlet point . At the first and at the fourth inlet point, the secondary air flowing through the first secondary air line can be introduced into the first exhaust line and the fourth exhaust line, with the further secondary air flowing through the second secondary air line being introduced into the second exhaust line and at the third inlet point can be introduced into the third exhaust line. The secondary air lines are therefore systems that are individual to the flow, via which the secondary air and the further secondary air can be introduced into the exhaust gas lines in a particularly advantageous manner. the exhaust pipes are parts of the exhaust system and are therefore also referred to as exhaust system parts.

• - Umsetzung einer Sekundärlufteinblasung bei minimalem Bauraum
• - Kostenreduzierung gegenüber herkömmlichen Lösungen
• - deutlich erweiterter Betriebsbereich gegenüber herkömmlichen Lösungen, da herkömmliche Sekundärluftpumpen vor allem bei Hybrid-Anwendungen nicht in der Lage sind, erforderliche Druckverhältnisse bei hohen Motorlasten zu liefern. Dies kann jedoch bei der Erfindung realisiert werden.

In particular, the following advantages can be realized by the invention:

• - Implementation of a secondary air injection with minimal installation space
• - Cost reduction compared to conventional solutions
• - Significantly extended operating range compared to conventional solutions, since conventional secondary air pumps are not able to deliver the required pressure ratios at high engine loads, especially in hybrid applications. However, this can be realized in the invention.

A second aspect of the invention relates to a motor vehicle, preferably designed as a motor vehicle, which has an internal combustion engine according to the first aspect of the invention and can be driven by the internal combustion engine. Advantages and advantageous configurations of the first aspect of the invention are to be regarded as advantages and advantageous configurations of the second aspect of the invention and vice versa.

Further advantages, features and details of the invention result from the following description of preferred exemplary embodiments and from the drawing. The features and combinations of features mentioned above in the description and the features and combinations of features mentioned below in the description of the figures and/or shown alone in the figures can be used not only in the combination specified in each case, but also in other combinations or on their own, without going beyond the scope of the leave invention.

• 1 eine schematische Darstellung einer ersten Ausführungsform einer erfindungsgemäßen Verbrennungskraftmaschine für ein Kraftfahrzeug;
• 2 eine schematische Darstellung einer zweiten Ausführungsform der Verbrennungskraftmaschine;
• 3 eine schematische Darstellung einer dritten Ausführungsform der Verbrennungskraftmaschine;
• 4 eine schematische Darstellung einer vierten Ausführungsform der Verbrennungskraftmaschine; und
• 5 eine schematische Darstellung einer fünften Ausführungsform der Verbrennungskraftmaschine.

The drawing shows in:

• 1 a schematic representation of a first embodiment of an internal combustion engine according to the invention for a motor vehicle;
• 2 a schematic representation of a second embodiment of the internal combustion engine;
• 3 a schematic representation of a third embodiment of the internal combustion engine;
• 4 a schematic representation of a fourth embodiment of the internal combustion engine; and
• 5 a schematic representation of a fifth embodiment of the internal combustion engine.

Elements that are the same or have the same function are provided with the same reference symbols in the figures.

1 shows a schematic representation of a first embodiment of an internal combustion engine 10 designed as a reciprocating piston engine and also referred to as an internal combustion engine for a motor vehicle, in particular for a motor vehicle. In the present case, the internal combustion engine 10 has exactly four along an imaginary straight line and thus arranged in a row one behind the other or one after the other Cylinder 12a-d, which are formed or limited by a cylinder housing 14 of the internal combustion engine 10. Cylinder 12a is referred to as the first cylinder, cylinder 12b is referred to as the second cylinder, cylinder 12c is referred to as the third cylinder, and cylinder 12d is referred to as the fourth cylinder. In particular, the first cylinder is also referred to as cylinder 1, the second cylinder is also referred to as cylinder 2, the third cylinder is also referred to as cylinder 3, and the fourth cylinder is also referred to as cylinder 4. The first cylinder 12a delimits a first combustion chamber 16a, the second cylinder 12b delimits a second combustion chamber 16b, the third cylinder 12c delimits a third combustion chamber 16c and the fourth cylinder 12d delimits a fourth combustion chamber 16d. Internal combustion engine 10 therefore also has exactly four combustion chambers in the form of combustion chambers 16a-d, in which combustion processes take place during fired operation of internal combustion engine 10. A respective piston is arranged in a translationally movable manner in the respective cylinder 12a-d, with the respective piston partially delimiting the respective combustion chamber 16a-d.

The internal combustion engine 10 has an exhaust gas tract 18 through which exhaust gas from the combustion chambers 16a-d can flow and in which, for example, an exhaust gas aftertreatment device (not shown in the figures) for aftertreatment of the exhaust gas can be arranged. During the fired operation, a fuel-air mixture, which preferably includes a liquid fuel and fresh air, is burned in the respective combustion process taking place in the respective combustion chamber 16a-d. Exhaust gas is produced by burning the fuel-air mixture.

The internal combustion engine 10 comprises an intake tract 20 through which the mentioned fresh air can flow and is also referred to as the intake tract, by means of which the fresh air flowing through the intake tract (AS 20) flows to and into the combustion chambers 16a-d and thus to and into the cylinders 12a-d is conducted.

The internal combustion engine 10 also includes an exhaust gas turbocharger 22 which has a compressor 24 arranged in the intake tract 20 and a turbine 26 arranged in the exhaust tract 18 . The compressor 24 includes a compressor wheel 28 which is arranged in the intake section 20 and by means of which the fresh air flowing through the exhaust section 2 can be compressed. The turbine 26 includes a turbine wheel 30 which is arranged in the exhaust tract 18 and can be driven by the exhaust gas. The exhaust gas turbocharger 22 includes a shaft 32 via which the compressor wheel 28 can be driven by the turbine wheel 30 . By driving the compressor wheel 28 , the fresh air flowing through the intake tract 20 is compressed by means of the compressor wheel 28 .

A charge air cooler 34 is arranged downstream of the compressor wheel 29 in the flow direction of the fresh air flowing through the intake tract 20, by means of which the compressed and thereby heated fresh air is cooled before it flows into the combustion chambers 16a-d. Furthermore, in the flow direction of the fresh air flowing through the intake tract 20, a throttle valve 36 is arranged downstream of the compressor wheel 28 and upstream of the charge air cooler 34, by means of which a quantity of fresh air to be supplied to the combustion chambers 16a-d can be adjusted.

The internal combustion engine 10 also includes a secondary air line 38 through which secondary air can flow, by means of which the secondary air flowing through the secondary air line 38 can be introduced into the exhaust tract 18 bypassing all combustion chambers 16a-d of the internal combustion engine 10 . The secondary air introduced into the exhaust tract 18 can, for example, form a secondary air/fuel mixture with unburned and therefore combustible components of the aforementioned fuel, which mixture can be burned, for example, in the exhaust tract 18 and release of heat. As a result, for example, the aforementioned exhaust gas aftertreatment device can be heated up effectively and efficiently, that is to say heated. The above-mentioned components of the fuel taken up in exhaust gas tract 18 or in the exhaust gas are, for example, fuel components that have reached exhaust gas tract 18 unburned from at least one of combustion chambers 16a-d and/or in a targeted manner, in particular by bypassing all combustion chambers 16a-d and/or are introduced into the exhaust tract 18 via at least one of the combustion chambers 16a-d.

Furthermore, the internal combustion engine 10 includes a valve element 40, by means of which a quantity of the secondary air flowing through the secondary air line 38 can be adjusted. For example, the valve element 40 can be switched or adjusted between at least one closed position and at least one release position. In the closed position, the valve element 40 blocks the secondary air line 38 so that no secondary air can flow through the secondary air line 38 . In the release position, the valve element 40 releases the secondary air line 38 , for example, so that secondary air can flow through the secondary air line 38 in the release position and can be introduced into the exhaust tract 18 by means of the secondary air line 38 . The introduction of the secondary air into the exhaust tract 18 is also referred to as secondary air injection, secondary air supply or secondary air introduction.

In order to be able to implement a particularly advantageous injection of secondary air into the exhaust tract 18, the valve element 40 is designed as a combination valve, via which the secondary air line 38 is fluidically connected or can be connected to the intake tract 20 at a branch point A arranged downstream of the compressor wheel 28 and upstream of the throttle valve 36 is. At the branching point A, at least part of the fresh air can be branched off from the intake tract 20 and consequently discharged or discharged. The fresh air branched off from intake tract 20 at branch point A, or its previously mentioned part, can be introduced via valve element 40 into secondary air line 38 and, as the aforementioned secondary air, can be introduced into exhaust tract 18 by means of secondary air line 38 . This means that the aforementioned part of the fresh air branched off from the intake tract 20 at the branching point A is the aforementioned secondary air or is used as the secondary air. Since the branching point A is arranged downstream of the compressor wheel 28, the compressor wheel 28 or the compressor 24 can be used as a secondary air pump in order to convey the secondary air, in particular to convey it into the secondary air line 38 and/or to convey it through the secondary air line 38 and/or or to promote in the exhaust tract 18 inside. As a result, an additional separate secondary air pump can be avoided, so that the number of parts, the weight, the costs and the installation space requirement of the internal combustion engine 10 can be kept within a particularly small framework. It can be seen that the secondary air flowing through the secondary air line 38 comes from the intake tract 20 and is introduced into the exhaust tract 18 bypassing the or all of the combustion chambers 16a-d. This means that the secondary air does not flow through any combustion chamber of internal combustion engine 10 .

Furthermore, it is provided that the turbine 26 is designed as a segment turbine. This means that the turbine 26 has at least or exactly two segments, which are also referred to as turbine segments and 1 are denoted by S1 and S2. For example, the turbine 26 includes a turbine housing, which forms or delimits a receiving space. The turbine wheel 30 is arranged in the receiving space and is rotatable relative to the turbine housing. The segments S1 and S2 are, in particular, delimited or formed by the turbine housing, channels through which the exhaust gas can flow, which, for example, run spirally in the circumferential direction of the turbine wheel over its circumference. Thus, the channels or segments S1 and S2 are preferably spiral channels or spiral segments. The segments S1 and S2 (channels) open into the receiving space via respective outflow cross sections through which the exhaust gas can flow. This means that the exhaust gas can flow out of the respective segment S1 or S2 via the respective outflow cross section and can flow into the receiving space. The outflow cross sections are not arranged one behind the other or one after the other in the axial direction of the turbine wheel 30, but the outflow cross sections are arranged one behind the other or one after the other in the circumferential direction of the turbine wheel 30 over its circumference. Thus, the segments S1 and S2 flow into the AR in the circumferential direction of the turbine wheel 30 over its circumference in succession. In other words, the segments S1 and S2 are distributed in the circumferential direction of the turbine wheel 30 over its circumference or arranged one behind the other. As a result, passive secondary air injection into the exhaust tract 18 is possible without an additional, separate secondary air pump, so that the number of parts, the space requirement, the costs and the weight can be kept particularly low. Furthermore, the secondary air line 38 and the valve element 40 have a dual function. On the one hand, the secondary air line 38 is used to introduce the secondary air into the exhaust tract 18, that is to say to blow it. In this respect, the valve element 40 is used on the one hand as a secondary air valve in order to adjust the quantity of secondary air flowing through the secondary air line 38 and to be introduced into the exhaust gas tract 18 . On the other hand, the secondary air line 38 is used, so to speak, to implement a type of overrun air or overrun air system, with the valve element 40 being used in this regard as an overrun air valve or as a type of overrun air valve. Since branch point A is located downstream of compressor wheel 28 and upstream of throttle valve 36, for example when the initially open throttle valve 36 is closed, in particular abruptly, an excessive braking of compressor wheel 28 caused by the fresh air compressed by compressor wheel 28 can be avoided in that at least part of the fresh air initially arranged between compressor wheel 28 and throttle valve 36 is branched off from intake tract 20 at branch point A and is introduced via valve element 40 into secondary air line 38.

A further function of the valve element 40 can preferably be that the valve element 40 is designed or can be operated as a check valve. The check valve blocks in the direction of branch point A, so that, for example, secondary air from secondary air line 38 does not return through valve element 40 to branch point A flow, and therefore cannot flow through the valve element 40 in a first flow direction pointing to the branch point A. However, valve element 40 opens in the opposite direction, i.e. in a second flow direction opposite to the first flow direction and pointing away from branch point A, so that part of the fresh air flows as secondary air in the second flow direction through valve element 40 and thus into secondary air line 38 can flow in.

Furthermore, it is off 1 recognizable that the first cylinder 12a or the first combustion chamber 16a is fluidly connected to a first exhaust line 42 of the exhaust tract 18 . The second cylinder 12b or the second combustion chamber 16b is fluidically connected to a second exhaust line 44 of the exhaust tract 18, the second exhaust line 44 being at least partially separate from the exhaust line 42, and the cylinders 12a and 12b being adjacent to one another. The third cylinder 12c or the third combustion chamber 16c is fluidly connected to a third exhaust line 46 of the exhaust tract 18, wherein the exhaust line 46 is at least partially fluidly separated from the exhaust lines 42 and 44. In addition, cylinder 12c is adjacent to cylinder 12b. The cylinder 12d or the combustion chamber 16d is fluidly connected to a fourth exhaust line 48 of the exhaust tract 18, the exhaust line 48 being at least partially fluidically separated from the exhaust lines 42, 44 and 46. In this case, the cylinder 12d is adjacent to the cylinder 12c. For example, the exhaust lines 42, 44, 46 and 48 are formed by an exhaust manifold 50 of the exhaust tract 18. The exhaust manifold 50 is also referred to as an exhaust manifold, for example. It can be seen that the exhaust gas lines 42 and 48 and thus the cylinders 1 and 4 are combined to form the segment S1 or open into the segment S1. The exhaust lines 44 and 46 and thus the cylinders 2 and 3 are brought together to form the segment S2 or open into the segment S2. In other words, combustion chambers 16a and 16d are fluidly connected to segment S1 via exhaust lines 42 and 48, while combustion chambers 16b and 16c are fluidly connected to segment S2 via exhaust lines 44 and 46.

At the in 1 The first embodiment shown has, in relation to the exhaust lines 42, 44, 46 and 48, only the exhaust lines 42 and 48 each have exactly one inlet point E1 or E4, at which the secondary air flowing through the secondary air line 38 enters the respective exhaust line 42 or 48 and thus into the exhaust tract 18 can be initiated. The secondary air line 38 is fluidically connectable or connected to the exhaust gas line 42 at the inlet point E and the secondary air line 38 is fluidically connectable or connected to the exhaust gas line 48 at the inlet point E4. There is no introduction of secondary air from the secondary air line 38 into the exhaust gas line 44 and 46 .

In connection with a surge charging of the segment turbine through a combination of increased exhaust gas energy and a strong separation of the segments S1 and S2, which is provided for the segment turbine and is also referred to as flow separation, there is the possibility of combining a secondary air system and an overrun air recirculation system, in particular through the above-described one The secondary air line 38 and the valve element 40 have a dual function. As a result, the complexity of the internal combustion engine 10 can be reduced compared to conventional solutions.

2 shows a second embodiment of the internal combustion engine 10. The second embodiment differs from the first embodiment in particular in that, based on the exhaust lines 42, 44, 46 and 48, only the second exhaust line 44 and the third exhaust line 46 each have exactly one inlet point E2 or E3 , at which the secondary air flowing through the secondary air line 38 can be introduced into the exhaust line 44 or 46 and thus into the exhaust tract 18 . A secondary air injection is thus omitted in the exhaust gas lines 42 and 48 . Thus, while secondary air is injected only into the exhaust gas lines 42 and 48 of cylinders 1 and 4 in the first embodiment, secondary air is injected only into the exhaust gas lines 44 and 46 of cylinders 2 and 3 in the second embodiment.

3 shows a third embodiment of the internal combustion engine 10. In the third embodiment, the internal combustion engine 10 comprises a second secondary air line 52, which is at least partially fluidically separate from the secondary air line 38, also referred to as the first secondary air line, and through which further secondary air can flow, and a second secondary air line 52, which is provided, for example, in addition to the valve element 40 second valve element 54. The previous and following statements regarding the secondary air line 38 and the valve element 40 can also be readily applied to the secondary air line 52 and the associated valve element 54 and vice versa. Valve element 54 is thus also embodied, for example, as a combination valve, via which second secondary air line 52 is fluidically connected to intake tract 20 at a second branch point A2 that is arranged downstream of compressor wheel 28 and upstream of throttle valve 36 and is spaced apart from branch point A, for example is bound or connectable, at which at least a further part of the fresh air can be branched off from the intake tract 20, can be introduced into the second secondary air line 52 via the second valve element 54 and can be introduced as the further secondary air into the exhaust tract 18 by means of the second secondary air line 52. For example, branch point A2 is arranged downstream of branch point A. The third embodiment is thus a combination of the first embodiment and the second embodiment, with the secondary air line 38 being fluidically connected to the exhaust lines 42, 44, 46 and 48 exclusively with the exhaust lines 42 and 48 (ZR 1 and 4) as in the first embodiment or is connectable. With respect to the exhaust gas lines 42, 44, 46 and 48, the second secondary air line 52 is connected exclusively to the exhaust gas lines 44 and 46 (cylinders 2 and 3). The secondary air line 38 and the valve element 40 thus form a first flow system, and the secondary air line 52 and the valve element 54 form a second flow system, the flow systems being individual flow systems via which the exhaust gas lines 42, 44, 46 and 48, in particular with regard to the segments S1 and S2 of the segment turbine can be supplied with the secondary air in a particularly advantageous manner.

In the third embodiment, the valve elements 40 and 54 are two separate secondary air valves. It is conceivable to combine the valve elements 40 and 54 and replace them, for example, with a single valve element, via which the secondary air lines 38 and 52 can be supplied with the secondary air, in particular in such a way that the secondary air lines 38 and 52 are fluidically connected via the common secondary air valve to the branch points A or A2 or are fluidically connected or connectable to a branch point common to the secondary air lines 38 and 52, such as branch point A or branch point A2.

4 12 shows a fourth embodiment of the internal combustion engine 10. In the fourth embodiment, the one secondary air line 38 is fluidically connected or can be connected to the exhaust gas lines 42, 44, 46 and 48 at the introduction points E1, E2, E3 and E4. The turbine 26 can be designed as a segment turbine or as another turbine.

Finally shows 5 a fifth embodiment. In the fifth embodiment, the exhaust gas turbocharger 22 is designed as an electrically assisted exhaust gas turbocharger (euATL). The exhaust gas turbocharger 22 comprises an in 5 particularly shown schematically, electric machine 56, by means of which at least the compressor wheel 28 can be driven electrically. The exhaust gas turbocharger 22 can thus be used particularly advantageously as a secondary air pump, so that a particularly large quantity of the secondary air can be introduced into the exhaust tract 18 via the secondary air line 38 . The use of an additional, separate secondary air pump can thus be dispensed with.

Reference List

10

internal combustion engine

12a-d

cylinder

14

cylinder body

16a-d

combustion chamber

18

exhaust tract

20

intake tract

22

exhaust gas turbocharger

24

compressor

26

turbine

28

compressor wheel

30

turbine wheel

32

Wave

34

intercooler

36

throttle

38

secondary air line

40

valve element

42

exhaust pipe

44

exhaust pipe

46

exhaust pipe

48

exhaust pipe

50

exhaust manifold

52

secondary air line

54

valve element

56

electric machine

A, A2

junction

E1 - E4

discharge point

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 10348131 A1 [0002]

Claims (5)

Internal combustion engine (10) for a motor vehicle, with an exhaust gas section (18) through which exhaust gas from at least one combustion chamber (16a) of the internal combustion engine (10) can flow, with an intake section (20) through which at least fresh air can flow, by means of which the Fresh air can be introduced into the combustion chamber (16a), with an exhaust gas turbocharger (22) which has a turbine (26) with a turbine wheel (30) arranged in the exhaust gas section (18) and which can be driven by the exhaust gas and a turbine wheel (30) arranged in the intake section (20). Compressor (24) with a compressor wheel (26) for compressing the fresh air to be introduced into the combustion chamber (16a), with at least one secondary air line (38) through which secondary air can flow, by means of which the secondary air flowing through the secondary air line (38) is fed into the exhaust tract (18) can be introduced, and having a valve element (40) by means of which a quantity of the secondary air flowing through the secondary air line (38) once adjustable, characterized in that the valve element (40) is designed as a combination valve, via which the secondary air line (38) is fluidically connected or can be connected to the intake tract (20) at a branch point (A) arranged downstream of the compressor wheel (26). which at least part of the fresh air can be branched off from the intake tract (20), can be introduced into the secondary air line (38) via the valve element (40) and can be introduced into the exhaust tract (18) as the secondary air by means of the secondary air line (38), the turbine ( 26) is designed as a segment turbine. Internal combustion engine (10) after claim 1 , characterized in that the valve element (40) is designed or can be operated as a non-return valve which blocks in the direction of the branch point (A) and opens in the opposite direction. Internal combustion engine (10) after claim 1 or 2 , characterized in that the compressor wheel (28) is assigned an electric machine (56) by means of which the compressor wheel (28) can be driven electrically. Internal combustion engine (10) according to one of the preceding claims, characterized in that the internal combustion engine (10) has at least or exactly four cylinders (12a-d), a first of the cylinders (12a-d) having the at least one combustion chamber (16a) as the first Combustion chamber (16a) is partially delimited and is fluidically connected to a first exhaust line (42) of the exhaust tract (18) through which exhaust gas from the first cylinder (12a) can flow, a second of the cylinders (12a-d) has a second combustion chamber (16b) of the Internal combustion engine (10) partially delimited and having a second exhaust line (44) of the exhaust tract (18) through which exhaust gas from the second cylinder (12b) adjacent to the first cylinder (12a) can flow and which is at least partially fluidically separated from the first exhaust line (42) is fluidly connected, a third of the cylinders (12a-d) a third combustion chamber (16c) of the internal combustion engine (10) partially bounded and having an exhaust gas from the second cylinder he (12b) adjacent, third cylinder (12c) through which fluid can flow and which is at least partially fluidically separated from the first and second exhaust gas lines (42, 44), the third exhaust gas line (46) of the exhaust tract (18) is fluidically connected, and the fourth cylinder (12d) a fourth combustion chamber (16d) of the internal combustion engine (10) partially delimited and having an exhaust gas from the fourth cylinder (12d) adjacent to the third cylinder (12c) through which it can flow and at least partially fluidly from the first, second and third exhaust gas line (42, 44 , 46) is fluidically connected to a separate, fourth exhaust line (48) of the exhaust tract (18), and wherein: - based on the exhaust lines (42, 44, 46, 48) only the second exhaust line (44) and the third exhaust line (46) each have at least or exactly one introduction point (E2, E3) at which the secondary air flowing through the secondary air line (38) can be introduced into the exhaust gas tract (18), or - based on the exhaust gas lines (42, 44, 46, 48) exclusively the first exhaust pipe (42) and the fourth exhaust pipe (48) each have at least or exactly one introduction point (E1, E4) at which the secondary air flowing through the secondary air pipe (38) can be introduced into the exhaust tract (18), or - a second secondary air line (52) which is at least partially fluidically separate from the secondary air line (38) and through which further secondary air can flow is provided, the first exhaust line (42) having at least or exactly one first introduction point (E1), the second exhaust line (44) having at least or exactly one second inlet point (E2), the third exhaust pipe (46) has at least or exactly one third inlet point (E3) and the fourth exhaust pipe (48) has at least or exactly one fourth inlet point (E4), wherein at the first and fourth inlet point ( E1, E3) the secondary air flowing through the first secondary air line (38) can be introduced into the exhaust tract (18), and wherein at the second and third introduction point ( E2, E3) the further secondary air flowing through the second secondary air line (52) can be introduced into the exhaust tract (18). Motor vehicle with an internal combustion engine (10) according to one of the preceding claims.

Images