Secondary air valve for a secondary air system of an internal combustion engine, internal combustion engine and motor vehicle

Description

[0001] The invention relates to a secondary air valve for a secondary air system of an internal combustion engine according to the preamble of claim 1. The invention further relates to an internal combustion engine for a motor vehicle, comprising a secondary air system. The invention also relates to a motor vehicle.

[0002] German patent DE 103 57 886 B4 discloses a valve for a secondary air supply system of an internal combustion engine, by means of which secondary air supplied to the system can be introduced into an exhaust system of the internal combustion engine. US patent 2016 / 0 115 845 A1 also discloses a secondary air valve. Furthermore, a discharge mechanism for compressed gas is known from German patent GB 2 520 038 A. Another valve is known from US patent 2005 / 204732 A1.

[0003] The object of the present invention is to provide a secondary air valve for a secondary air system of an internal combustion engine, an internal combustion engine and a motor vehicle, so that a particularly advantageous secondary air injection can be realized.

[0004] This problem is solved by a secondary air valve with the features of claim 1, by an internal combustion engine with the features of claim 6, and by a motor vehicle with the features of claim 9. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0005] A first aspect of the invention relates to a secondary air valve for a secondary air system of an internal combustion engine, also referred to as an internal combustion engine or combustion power unit, and designed, for example, as a reciprocating piston engine, i.e., a piston engine, of 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, in its fully manufactured state, has the secondary air system. Furthermore, the internal combustion engine, in its fully manufactured state, has an exhaust tract through which exhaust gas from the internal combustion engine flows, which is also referred to as the exhaust system.The internal combustion engine also has at least one combustion chamber, and in particular several combustion chambers, in which combustion processes take place in the respective combustion chamber during firing operation. In each combustion process, a fuel-air mixture is burned, resulting in exhaust gas from the internal combustion engine. The exhaust gas can flow out of the respective combustion chamber and into the exhaust system, subsequently flowing through it. Furthermore, the internal combustion engine has an intake manifold, which is also referred to as the intake system. The intake manifold is permeable to air, which is also referred to as fresh air. The intake manifold allows air to be directed to and into the respective combustion chamber, so that the fuel-air mixture can be formed from the air and a preferably liquid fuel.By means of the secondary air system, secondary air can be introduced into the exhaust tract, in particular directly, bypassing the respective combustion chamber, i.e. bypassing the combustion chamber(s) of the internal combustion engine, so that the secondary air on its way through the secondary air system and to and into the exhaust tract does not flow through the respective combustion chamber, in particular through none of the combustion chambers, of the internal combustion engine, thus bypassing the respective combustion chamber, in particular the combustion chamber(s) of the internal combustion engine.

[0006] The exhaust system contains, for example, at least one exhaust aftertreatment component for treating the exhaust gas. The secondary air, and in particular the oxygen it contains, is used, for example, to effectively and efficiently heat and / or maintain the temperature of the exhaust aftertreatment component. In this context, the secondary air, and in particular the oxygen it contains, is used, for example, to oxidize, and thus combust, unburned fuel, i.e., unburned hydrocarbons, in the exhaust system, and in particular in the exhaust aftertreatment component. This fuel can, in particular, be the fuel itself.

[0007] For example, the secondary air system has a secondary air duct through which the secondary air flows, and which can be fluidically connected to the intake manifold at a connection point. This allows, for example, at least a portion of the air flowing through the intake manifold to be diverted at the connection point and introduced into the secondary air duct. The air diverted from the intake manifold and introduced into the secondary air duct can then flow through the secondary air duct as secondary air and is directed to the exhaust manifold, bypassing the combustion chamber. Thus, a portion of the air flowing through the intake manifold is used as secondary air. The secondary air valve, for example, is located in the secondary air duct.For example, the secondary air valve can be used to regulate the amount of secondary air flowing through the secondary air line. In particular, it is conceivable that the secondary air valve can be used to selectively block or open the secondary air line. If the secondary air valve opens the secondary air line, the secondary air can flow through it and subsequently be introduced into the exhaust system. If the secondary air valve blocks the secondary air line, no secondary air, or air from the intake manifold, can flow through it.

[0008] The secondary air valve has a valve housing, also referred to simply as a housing, through which the secondary air to be introduced into the exhaust system of the internal combustion engine can flow. The valve housing has a cylindrical chamber, which is directly bounded by an inner circumferential surface of the valve housing. The valve housing has, in particular, at least or exactly, an inlet opening through which the secondary air can be introduced into the valve housing and into the chamber. In particular, it is conceivable that the inlet opening is fluidically connected or connectable to the intake manifold, especially at the connection point. For example, the inlet opening opens, in particular directly, into the chamber. Thus, for example, the chamber is fluidically connected to the intake manifold via the inlet opening.In particular, the valve element is arranged at least partially in the valve housing and thus at least partially in the housing space, at least in the closed position, and especially in the closed and open positions.

[0009] The valve housing also has, in particular precisely or at least, an outlet opening through which the secondary air, i.e., the air taken in or capable of being taken in the housing space (also referred to as the receiving chamber), can be discharged or vented from the valve housing, i.e., from the housing space. By venting the secondary air through the outlet opening from the valve housing and thus from the housing space, the secondary air can be introduced into the exhaust system.

[0010] The secondary air valve also has a valve element which is movable along a direction of movement relative to the valve housing between a closed position and at least one open position, in particular translationally. In the closed position, the outlet opening is closed by the valve element, i.e., fluidically blocked, so that the secondary air, or the air that can be drawn in or is drawn into the housing, cannot flow through the outlet opening and thus cannot flow out of the valve housing and therefore out of the secondary air valve as a whole. In the open position, the valve element releases the outlet opening, so that the secondary air, or the air that can be drawn in or is drawn into the housing, can flow through the outlet opening and thus out of the valve housing and therefore out of the secondary air valve as a whole.Thus, for example, the secondary air line is closed in the closed position by means of the valve element and therefore by means of the secondary air valve. In the open position, for example, the secondary air line is open. In other words, for example, the valve element and therefore the secondary air valve open the secondary air line. Thus, for example, the air diverted from the intake manifold at the connection point can flow through the secondary air valve and subsequently the secondary air line in the open position of the valve element, specifically in such a way that the secondary air originating from the intake manifold can flow into the valve housing through the inlet opening and out of the valve housing and thus out of the secondary air valve altogether through the outlet opening.

[0011] For example, particularly during or in the operation of the internal combustion engine, where air flows through the intake tract during operation, a pressure also referred to as housing pressure or housing pressure prevails in the housing space and / or the housing pressure acts particularly via the inlet opening on the valve element, which is, for example, in the closed position, wherein the housing pressure is caused, for example, by air that is contained in the housing space and / or by air that is contained in the secondary air line, particularly in a first section of the secondary air line, and acts on the valve element, which is, for example, in the closed position, particularly via the inlet opening.The housing pressure prevailing in the housing chamber and / or in the first duct section, and acting particularly on the valve element (e.g., in the closed position), corresponds, for example, to the pressure prevailing in the intake tract, also referred to as intake tract pressure, because the housing chamber is fluidically connected to the intake tract via the inlet opening. This pressure is caused, for example, by the air flowing through the intake tract. Particularly when the connection point is located downstream of a compressor in the intake tract, by which the air flowing through the intake tract is compressed, the intake tract pressure, and thus the housing pressure, can be very high and, in particular, higher than the ambient pressure.Specifically, the air flowing through the intake tract and drawn into the housing is the air compressed by the compressor, also known as charge air. The intake tract pressure is then also referred to as boost pressure, meaning the housing pressure is or corresponds to the boost pressure.

[0012] Thus, for example, the first section of the secondary air line can be fluidically connected to the intake manifold at the connection point, and the first section of the secondary air line can also be fluidically connected to the inlet opening. Therefore, the intake manifold pressure can act as the housing pressure via the first section of the line within the housing, and / or the intake manifold pressure can act on the valve element via the first section of the line and the inlet opening. In other words, for example, in both the closed and open positions, at least some of the air flowing through the intake manifold can enter the housing as secondary air via the first section of the line and the inlet opening, thus causing the housing pressure within the housing.In particular, the intake manifold pressure can act on the valve element via the first duct section and the inlet opening when the valve element is closed. A second duct section of the secondary air line is, for example, fluidically connected or connectable to the exhaust manifold, especially at an inlet point, and, for example, the second duct section is fluidically connected to the outlet opening. This allows, for example, secondary air to flow through the outlet opening in the open position and thus into the second duct section, subsequently flowing through the second duct section and being guided from the outlet opening to the inlet point via the second duct section, and finally being introduced into the intake manifold at the inlet point.

[0013] The closed position is also referred to as the first position or is a first position of the valve element. The open position is also referred to as the second position or is a second position of the valve element. In particular, it is provided that in both positions, i.e., both in the closed position and in the open position, the inlet opening is open, thus allowing airflow. This means that, for example, in both the closed and open positions, the housing pressure in the housing chamber, and thus in the valve housing, can act, in particular on the valve element. For example, at least in the closed position, the housing pressure in the housing chamber, and thus in the valve housing, can correspond to the intake manifold pressure. Therefore, in the closed position, the intake manifold pressure can act on the valve element via the inlet opening, and in particular directly.In summary, at least in the closed position, the housing pressure acting within the housing and / or the intake manifold pressure acting on the valve element via the inlet opening and especially the first section of the pipe can be very high, and in particular higher than ambient pressure, so that the housing pressure or the intake manifold pressure can be significantly greater than 1 bar. The introduction of secondary air into the exhaust manifold is also referred to as secondary air injection.

[0014] In order to achieve a particularly advantageous secondary air injection, it is provided according to the invention that the inlet opening, viewed along the direction of movement, is arranged, in particular completely, between two sealing elements by means of which the valve element is sealed against the valve housing.The valve element is free, at least on its outer circumference, in particular on its outer and inner circumference, and most preferably in principle, along its entire extent, at least in the closed position along the direction of movement between the sealing elements, from a surface running obliquely or perpendicular to the direction of movement, so that the intake manifold pressure and / or housing pressure acting on the valve element, for example at least in the closed position, does not cause a force acting on the valve element along the direction of movement, nor does it cause a force that has a force component running along or in the direction of movement.In other words, the invention prevents the intake manifold pressure from exerting a force on the valve element in the closed position, either parallel or oblique to the direction of movement, which could open the valve element and thus move it from the closed to the open position. This allows the valve element to be held securely in the closed position, thus protecting it from unwanted opening and movement from the closed to the open position. Put another way, the invention prevents unwanted movements of the valve element relative to the valve housing caused by the housing pressure or the intake manifold pressure, particularly from the closed to the open position, so that, for example, the valve element remains securely in the closed position and does not open unintentionally.In particular, the invention makes it possible to arrange the aforementioned connection point such that it is located downstream of the compressor, allowing the charge air, or at least a portion thereof, to be used as the secondary air. Thanks to the invention, the high housing pressure or intake manifold pressure does not cause the valve element to open unintentionally, i.e., to move unintentionally from the closed to the open position. This allows for on-demand secondary air injection, and in particular, at least a portion of the charge air can be used as the secondary air, enabling secondary air injection to be carried out, for example, in particularly advantageous operating ranges or especially during a cold start of the internal combustion engine.

[0015] The sealing elements seal an outer surface of the valve element, facing the inner surface, against the inner surface of the valve housing. This prevents excessive flow of air or secondary air from the intake tract between the inner and outer surfaces, thus reliably preventing unwanted airflow and any resulting forces acting on the valve element that could open it. Specifically, the inner surface is aligned with the outer surface, particularly along a direction perpendicular to the direction of movement.

[0016] The valve element is designed as a disc- or disk-shaped valve and comprises a disc- or disk-shaped valve part and a valve stem to which the valve part is connected. The secondary air valve also features a third sealing element, which seals the valve part against the valve housing in the closed position.

[0017] The invention is based in particular on the following findings and considerations: Conventional secondary air systems have only a very small, near-idle operating range. This means that conventional secondary air systems can only be used to perform secondary air injection in a small, near-idle operating range of the internal combustion engine. However, in order to perform secondary air injection even during cold starts with higher loads, a high secondary air pressure is required, because then, and especially only then, can the secondary air be injected into the exhaust system against an increasing exhaust gas pressure, also known as exhaust gas pressure.Therefore, it is advantageous to connect the secondary air line, particularly the first section of the line, to the intake manifold, and especially at the connection point, thus fluidically connecting the secondary air line, particularly the first section of the line, to the intake manifold at the connection point, with the connection point preferably being located downstream of the aforementioned compressor. This allows at least a portion of the charge air compressed by the compressor to be used as the secondary air, enabling a particularly high secondary air pressure to be achieved. In particular, the secondary air pressure can then correspond at least almost to the charge pressure. Specifically, the secondary air pressure can then be greater than 2 bar.However, it was found that conventional secondary air valves are not airtight at such high secondary air bridge pressures, and therefore cannot keep the secondary air line closed. Instead, they open undesirably, and especially automatically, at high secondary air pressures, for example, greater than 500 mbar, thus undesirably releasing the secondary air line, particularly without the conventional secondary air valves being actuated. This can now be avoided by the invention, making it possible to connect the secondary air line to the intake manifold and, in particular, to use at least a portion of the charge air as secondary air. Furthermore, it was found that conventional secondary air valves only remain airtight up to a pressure of approximately 500 mbar.At higher pressures, conventional secondary air valves open automatically and undesirably, making them unsuitable for use as secondary air for charge air with a pressure greater than 500 mbar, particularly greater than 1 bar, and especially greater than 2 bar. However, this can now be achieved by the invention.

[0018] In order to reliably prevent forces acting on the valve element resulting from the housing pressure or the intake tract pressure, which could open the closed valve element and thus keep the valve element securely in the closed position, one embodiment of the invention provides that the valve element is cylindrical on its outer circumference along its entire extent, at least in the closed position along the direction of movement between the sealing elements, and thus has the shape of a straight circular cylinder.This results in a cylindrical shape of the valve element on its outer circumference, at least over its entire extent, particularly in the closed position, extending between the sealing elements in the direction of movement. This prevents the intake manifold pressure or the housing pressure from exerting an axial force, i.e., a force acting on the valve element along or oblique to the direction of movement, which could open the valve element. Thus, the secondary air line, particularly the first section of the line, can advantageously be fluidically connected to the intake manifold at the connection point, preferably located downstream of the compressor, and the valve element can be held securely closed.For example, the secondary air valve comprises a spring element, in particular designed as a mechanical spring, by means of which, for example, the valve element is held or retained in the closed position. The invention makes it possible to hold the valve element, in particular by means of the spring element, especially advantageously in the closed position even when the air from the intake tract has a high pressure, such as the boost pressure, and is therefore, for example, charge air.

[0019] The respective sealing element is preferably made of rubber, i.e., of an elastically deformable material. For example, the respective sealing element rests, on one side, particularly directly, against the inner circumferential surface of the valve housing and, on the other side, particularly directly, against the outer circumferential surface of the valve element.

[0020] The valve element and the valve housing are also referred to as components of the secondary air valve. For example, the respective sealing element is arranged in a corresponding recess of one of the components, the recess being designed, for example, as a groove, particularly an annular groove. The sealing element is partially arranged in the recess and projects out of it, for example, in particular along an oblique or perpendicular direction to the direction of movement, so that the sealing element abuts the outer surface of the other component, in particular directly. Preferably, one component is the valve housing, and the other component is, for example, the valve element.This allows for a particularly advantageous seal, so that unwanted flows of air from the intake tract as well as unwanted movements of the valve element relative to the valve housing can be reliably avoided.

[0021] In order to seal the valve element particularly advantageously against the valve housing, a further embodiment of the invention provides that the sealing elements are designed separately from each other and spaced apart from each other along the direction of movement.

[0022] Another embodiment is characterized in that the sealing elements are held on the valve housing, so that the valve element is movable along the direction of movement relative to the valve housing and relative to the sealing elements between the closed and open positions, in particular translationally and, most importantly, purely translationally. This reliably prevents unwanted airflow and thus unwanted forces acting on the valve element that could unintentionally open it, thus enabling advantageous, demand-based secondary air injection.

[0023] Finally, it has proven particularly advantageous if the inlet opening has a flow direction along which the air flowing into or into the valve housing via the inlet opening can pass through it, wherein the flow direction is oblique or preferably perpendicular to the direction of movement. This prevents undesirable, excessive forces acting on the valve element that could move the valve element relative to the valve housing along the direction of movement, thus enabling a particularly advantageous and demand-oriented secondary air injection.

[0024] A second aspect relates to an internal combustion engine, also referred to as an internal combustion engine or combustion power unit, for a motor vehicle, wherein the internal combustion engine has a secondary air system comprising at least one secondary air valve according to the first aspect of the invention. 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.

[0025] One embodiment of the second aspect of the invention is characterized in that the internal combustion engine has the aforementioned exhaust tract and the aforementioned intake tract through which fresh air flows, by means of which the fresh air flowing through the intake tract can be introduced into the respective combustion chamber of the internal combustion engine. The secondary air system has the aforementioned secondary air line, which is fluidically connected or connectable to the intake tract at the connection point located upstream of the combustion chamber. Thus, at least a portion of the fresh air flowing through the intake tract can be diverted at the connection point on the intake tract by means of the secondary air line and introduced into the exhaust tract as secondary air, bypassing the respective combustion chamber. The secondary air line also has the secondary air valve, which is arranged in the secondary air line.This allows for a particularly advantageous secondary air injection.

[0026] Another embodiment of the second aspect of the invention is characterized in that the compressor is arranged in the intake tract for compressing the fresh air flowing through the intake tract, with the connection point being located downstream of the compressor. This allows a particularly high secondary air pressure to be achieved in a particularly simple manner, and the invention ensures that the valve element remains securely in the closed position.

[0027] A third aspect of the invention relates to a motor vehicle, also referred to as a vehicle, which has an internal combustion engine according to the second aspect and can be driven by means of the internal combustion engine. Advantages and advantageous embodiments of the first and second aspects of the invention are to be regarded as advantages and advantageous embodiments of the third aspect of the invention, and vice versa.

[0028] Further advantages, features, and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing. The features and combinations of features mentioned above in the description, as well as those mentioned below in the figure description and / or shown in the figures alone, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention.

[0029] The drawing shows in: Fig. 1 a schematic representation of an internal combustion engine of a motor vehicle; and Fig. 2 a schematic longitudinal sectional view of a secondary air valve of a secondary air system of the internal combustion engine, wherein a valve element of the secondary air valve is in an open position; and Fig. 3 a schematic longitudinal sectional view of the secondary air valve, wherein the valve element is in a closed position.

[0030] In the figures, identical or functionally equivalent elements are provided with the same reference numerals.

[0031] Fig. 1Figure 10 shows a schematic representation of an internal combustion engine 10 of a motor vehicle, also referred to simply as a vehicle, which can be powered by the internal combustion engine 10. The internal combustion engine 10 has a cylinder housing 12, designed, for example, as a cylinder crankcase and also referred to as an engine block, which in this case has, for example, two cylinder banks 14 and 16, each with at least or exactly four cylinders 18. Each cylinder 18 forms or delimits a combustion chamber of the internal combustion engine 10, such that in the Fig. 1In the illustrated embodiment, the internal combustion engine 10 has exactly eight combustion chambers. The internal combustion engine 10 has an intake manifold 20, through which air, also referred to as fresh air, flows. The fresh air flowing through the intake manifold 20 is directed to and into the combustion chambers via the intake manifold 20. The internal combustion engine 10 also has an exhaust manifold 22, through which exhaust gas from the internal combustion engine 10, i.e., exhaust gas from the combustion chambers, flows. An exhaust gas turbocharger 24 is provided for each cylinder bank 14, 16, which has a turbine 26 arranged in the exhaust manifold 22 and a compressor 28 arranged in the intake manifold 20. The respective turbine 26 is driven by the exhaust gas flowing through the exhaust manifold 22.The respective compressor 28 of the respective exhaust gas turbocharger 24 can be driven, in particular via a respective shaft 30 of the respective exhaust gas turbocharger 24, by the respective turbine 26 of the respective exhaust gas turbocharger 24. By driving the respective compressor 28, the fresh air flowing through the intake tract 20 is compressed by the respective compressor 28. The fresh air compressed by the respective compressor 28 is also referred to as charge air. In the intake tract 20, a respective charge air cooler 32 is arranged downstream of the respective compressor 28, by means of which the compressed and thus heated charge air is cooled. Each compressor 28 is provided with a respective recirculation system 34 with a respective recirculation line 36 and a respective recirculation valve 38 arranged on the respective recirculation line 36.Furthermore, in the intake tract 20, a throttle valve 40 is arranged for each cylinder bank 14, 16, which is located downstream of the respective charge air cooler 32.

[0032] Each turbine 26 is associated with a bypass device 42, comprising a bypass line 44 and a bypass valve 46 located in the bypass line 44. At least a portion of the exhaust gas flowing through the exhaust tract 22 can bypass the turbine 26 via the bypass line 44. The amount of exhaust gas flowing through the bypass line 44, and thus bypassing the turbine 26, can be adjusted, for example, by means of the bypass valve 46. The bypass valve 46 is also referred to as a wastegate.

[0033] Downstream of each turbine 26, an exhaust aftertreatment device 48 is arranged in the exhaust tract 22. Each exhaust aftertreatment device 48 comprises exhaust aftertreatment elements 50a-c, by means of which the exhaust gas is treated. For example, exhaust aftertreatment element 50a is or comprises a catalyst, in particular a three-way catalyst. For example, each exhaust aftertreatment element 50b is or comprises a particulate filter. For example, the internal combustion engine 10 is designed as a gasoline engine, so that the particulate filter is, for example, a gasoline particulate filter (GPF). For example, each exhaust aftertreatment element 50c is or comprises a further catalyst, in particular a three-way catalyst. Each exhaust aftertreatment element 50a-c is also referred to as an exhaust aftertreatment component.

[0034] The internal combustion engine 10 also has a secondary air system 52. The secondary air system 52 has a secondary air line 54. The secondary air line 54 has a first line section 56, which is fluidically connected to the intake manifold 20 at a connection point V. It can be seen that the connection point V is located upstream of the combustion chambers and downstream of the compressor 28. For each cylinder bank 14, 16, the secondary air line 54 has a second line section 58. The line section 56 is a line section common to the line sections 58. The secondary air line 54 is permeable to secondary air, whereby the secondary air initially flowing through line section 56 is divided among the line sections 58, thus being divided into respective partial flows flowing through the line sections 58.The secondary air flowing through the secondary air line 54 is introduced into the exhaust gas tract 22, bypassing the combustion chambers, at respective inlet points located downstream of the combustion chambers, where the secondary air line 54 is fluidically connected to the exhaust gas tract 22. Specifically, the respective second line section 58 is fluidically connected to the exhaust gas tract 22 at each inlet point. Fig. 1 It is evident that, for example, for each combustion chamber, in particular at least or exactly one inlet point is provided, at which the secondary air line 54, in particular the respective second line section 58, is fluidically connected to the exhaust gas tract 22.

[0035] The secondary air system 52 includes a secondary air pump 60, also referred to simply as a pump, by means of which, for example, the secondary air can be conveyed through the secondary air line 54. For example, the secondary air pump 60 is or operates as an auxiliary compressor by means of which the secondary air is compressed or is to be compressed. For example, the secondary air pump 60 is an electric pump, i.e., an electrically operated pump, so that, for example, the secondary air pump 60 is designed as an electric auxiliary compressor.

[0036] Since the connection point V is located upstream of the combustion chambers of the internal combustion engine 10 and downstream of the compressors 28, at least a portion of the charge air flowing through the intake tract 20 can be diverted from the intake tract 20 at connection point V via the secondary air line 54 and introduced into the exhaust tract 22 as secondary air, bypassing all combustion chambers of the internal combustion engine. Since the secondary air pump 60 is located downstream of connection point V, the air already compressed by the compressors 28 and used as secondary air is compressed again, so that the secondary air flowing through the secondary air line 54 is compressed air.

[0037] A pressure sensor 62 of the secondary air system 52 is arranged in the secondary air line 54. The pressure sensor 62 can be used to detect the pressure of the secondary air, particularly downstream of the secondary air pump 60 and upstream of the inlet points.

[0038] In the respective second line section 58, a secondary air valve 64 of the secondary air system 52 is arranged, such that the respective secondary air valve 64 (SLV) is located in the secondary air line 54. Thus, one secondary air valve 64 is provided for each cylinder bank 14, 16. It can be seen that the respective secondary air valve 64 is located upstream of the respective inlet point and downstream of the secondary air pump 60, in particular downstream of the pressure sensor 62.

[0039] The respective secondary air valve 64 is shown in a schematic longitudinal sectional view in the Figs. 2 and 3 shown. From Figs. 2 and 3It is evident that the secondary air valve 64 has a valve housing 66, which has a housing chamber 68, also referred to as a receiving chamber or valve chamber, and is in particular directly bounded. The housing chamber 68 is directly bounded by an inner circumferential surface 70 of the valve housing 66. The housing chamber 68 is cylindrical. The secondary air flowing through the secondary air line 54, in particular the respective second line section 58, can flow through the valve housing 66, in particular the housing chamber 68, so that the secondary air flows through the secondary air line 54 and thus through the valve housing 66, in particular through the housing chamber 68, on its way from the connection point V to the respective inlet point and thus to the exhaust tract 22.

[0040] The valve housing 66 has, in particular, an inlet opening 72 through which secondary air can flow into the valve housing 66 and thus into the housing chamber 68, i.e., be introduced. This is shown in Fig. 2 illustrated by an arrow 74. Furthermore, the valve housing 66, in particular, has an outlet opening 76 through which the secondary air flowing into the valve housing 66 and thus into the receiving chamber (housing chamber 68) via the inlet opening 72 can be discharged or diverted from the valve housing 66, in particular from the secondary air valve 64 as a whole, and thus can flow out.

[0041] The secondary air valve 64 also has a valve element 78, which extends along a Fig. 2 direction of movement relative to the valve housing 66 illustrated by a double arrow 80 between a closed position S closing the outlet opening 76 ( Fig. 3) and at least one opening O releasing the exit opening 76 ( Fig. 2 ) is translationally movable. It can be seen that in the closed position S, the valve element 78 closes the outlet opening 76, also referred to as the outflow opening, thus fluidically blocking it. In the open position O, the valve element 78 releases the outlet opening 76. Furthermore, it is evident from Figs. 2 and 3It is evident that in both the closed position S and the open position O, which are collectively referred to as positions, the inlet opening 72 is open, and thus accessible to air, particularly from the intake tract 20. In other words, in both positions, the housing chamber 68 is fluidically connected to the intake tract 20 via the inlet opening 72, which is accessible in both positions. Therefore, in the closed position S, air originating from the intake tract 20 and compressed, for example, by the respective compressor 28, can flow through the inlet opening 72 and thus enter the housing chamber 68 via the inlet opening 72 or act upon the valve element 78.Thus, for example, in the closed position S of the valve element 78, air is drawn in at least in part of the housing space 68 and therefore at least in part of the valve housing 66. This air originates from the intake tract 20 and, in particular when the internal combustion engine 10 is operating, is charge air, i.e., a portion of the charge air or a portion of the air compressed by the compressor 28. In other words, in the closed position S of the valve element 78, air originating from the intake tract 20 is present, which, in particular when the internal combustion engine 10 is operating, is charge air, i.e., a portion of the charge air or a portion of the air compressed by the compressor 28.Thus, the air taken in at least in the part of the housing space 68 in the closed position S of the valve element 78, which is also referred to as housing air, or the air acting on the valve element 78 via the inlet opening 72 in the closed position S of the valve element 78 and originating from the intake tract 20, has a high pressure, since, for example, the housing air or the air acting on the valve element 78 via the inlet opening 72 in the closed position S of the valve element 78 is the charge air or a part of the charge air.

[0042] The secondary air valve 64 has an actuator 82, in this case designed as a solenoid, which can be supplied with electrical energy and thus electrically controlled. In other words, the actuator 82 can be supplied with electrical energy, i.e., with electric current, which is also referred to as energizing the actuator 82. The secondary air valve 64 also has a spring element 84, which in this case is designed as a mechanical spring and thus as a solid body. For example, the spring element 84 is a helical spring. By energizing the actuator 82, i.e., by supplying the actuator 82 with electrical energy, the valve element 78, which is initially in the closed position S, can be moved from the closed position S to the open position O by means of the actuator 82, i.e., opened.This tensions the spring element 84, which in turn provides a spring force by which the valve element 78 can be moved from the open position O to the closed position S, thus closing it. For example, if the actuator 82 is de-energized, the valve element 78 is moved from the open position O to the closed position S by means of the spring force of the spring element 84. For example, the spring element 84 is tensioned in the closed position S, so that it also provides a spring force in the closed position S by means of which the valve element 78 is held in the closed position S. Thus, the secondary air valve 64 is closed when the actuator 82 is de-energized. By energizing the actuator 82, the valve element 78 is opened by the actuator 82 against the spring force of the valve element 84.

[0043] The valve element 78 is designed as a disc- or disk-shaped valve and includes a disc- or disk-shaped valve part 86. The valve element 78 also has a valve stem 88 to which the valve part 86 is connected. It is conceivable that the valve part 86 and the valve stem 88, which is also referred to as a rod or piston rod, are designed separately and connected to each other, or that the valve part 86 and the valve stem 88 are formed integrally, i.e., from a single piece. The valve stem 88 and the valve part 86, i.e., the valve element 78, are together movable translationally along the direction of movement relative to the valve housing 66 from the closed position S to the open position O and from the open position O to the closed position S.For example, the open position O and the closed position S are respective end positions, whereby the valve element 78 can be moved into the respective end position, but not beyond it. In particular, the actuator 82 can drive the valve stem 88 and, via this, the valve part 86, and thus move it relative to the valve housing 66, in particular opening it.

[0044] Furthermore, the spring force of the spring element 84 can drive the valve stem 88 and, via this, the valve part 86, thus closing it.

[0045] Since the inlet opening 72 is open in the closed position S, and since the housing chamber 68 is thus fluidically connected to the intake tract 20 via the inlet opening 72 in the closed position S, the valve element 78, in particular via the valve stem 88 in the closed position S, can be directly acted upon or is acted upon by the housing air flowing into the valve housing 66 and thus into the housing chamber 68 via the inlet opening 72 and / or the air originating from the intake tract 20 acts on the valve stem 88 and thus on the valve element 78 via the inlet opening 72 in the closed position S.

[0046] To prevent the secondary air valve 64 from opening unintentionally and to enable the injection and realization of a particularly advantageous secondary air supply, the secondary air valve 64 is designed so that the inlet opening 72, viewed along the direction of movement, is arranged between two sealing elements 90 and 92. These sealing elements seal an outer circumferential surface 94 of the valve element 78, facing the inner circumferential surface 70, against the inner circumferential surface 70 of the valve housing 66. This prevents, for example, an excessive amount of air acting on the valve element 78, and in particular on the outer circumferential surface 94, via the inlet opening 72, from flowing beyond the sealing elements 90 and 92 and between the outer surfaces 70 and 94.Furthermore, it is provided that the valve element 78 is free on its outer circumference, that is, on its outer circumferential surface 94 along its entire extent ER, at least in the closed position S along the direction of movement between the sealing elements 90 and 92, from a surface running obliquely or perpendicular to the direction of movement. In other words, the outer circumferential surface 94 of the valve element 78 has no surface over its entire extent E, at least in the closed position S along the direction of movement between the sealing elements 90 and 92, that extends in a plane that runs obliquely or perpendicularly to the direction of movement (double arrow 80).This prevents the air originating from the intake tract 20, which acts directly on the valve element 78, in particular the outer surface 94, via the inlet opening 72 in the closed position S, from exerting a force on the valve element 78 that has a force component extending along the direction of movement and could thus open the valve element 78. Therefore, the valve element 78 can be held securely in the closed position S, particularly by means of the spring element 84.

[0047] In the embodiment shown in the figures, the valve element 78 is designed to be cylindrical on its outer circumference, i.e., the outer surface 94 along its entire extent ER, at least in the closed position S along the direction of movement between the sealing elements 90 and 92, and thus has the shape of a straight circular cylinder.

[0048] In the embodiment shown in the figures, the sealing elements 90 and 92, which are made of rubber, for example, are formed separately from each other and then spaced apart from each other along the direction of movement, in particular completely. For example, the sealing elements 90 and 92 are held on the valve housing 66 so that the valve element 78 is movable along the direction of movement relative to the valve housing 66 and relative to the sealing elements 90 and 92 between the closed position S and the open position O.

[0049] The inlet opening 72 has a direction of passage, illustrated by arrow 74, along which the housing air or secondary air can flow through or is flowed through the inlet opening 72. The direction of passage is perpendicular to the direction of movement.

[0050] The secondary air valve 64 also has a third sealing element 96, which can, for example, be formed separately from the valve housing 66 and separately from the valve element 78. Alternatively or additionally, the sealing element 96 is formed separately from the sealing element 90 and / or separately from the sealing element 92 and is spaced away from the sealing element 90 and / or from the sealing element 92, in particular completely. The sealing element 96 can be made of rubber. In the closed position S, the sealing element 96 rests directly against the valve housing 66 and the valve element 78, in particular against the valve part 86, so that in the closed position S the valve element 78, in particular the valve part 86, is sealed against the valve housing 66 by means of the sealing element 96. This prevents excessive leakage.

[0051] Furthermore, it is preferably provided that the sealing element 90 and / or the sealing element 92 is formed separately from the valve element 78 and separately from the valve housing 66. The respective sealing element 90, 92 bears, on one hand, particularly directly, against the valve housing 66, especially a surface 70, and preferably, on the other hand, the respective sealing element 90, 92 bears, on the other hand, particularly directly, against the valve element 78, especially the valve stem 88 and, most particularly, against the surface 94. This ensures a particularly advantageous seal.

[0052] The secondary air valve 64 also has a check valve 98 which, in particular when viewed along the direction of movement, is arranged between the valve element 78, in particular the valve part 86, and the inlet opening 72.

[0053] The check valve 98 can be located further downstream in the flow towards the outlet channel. It also does not necessarily have to be integrated into the secondary air valve and could be housed in downstream components.

Claims

1. Secondary air valve (64) for a secondary air system (52) of an internal combustion engine (10), the secondary air valve comprising: - a valve housing (66) through which secondary air to be introduced into an exhaust tract (22) of the internal combustion engine (10) can flow and which has: ∘ a cylindrical housing chamber (68) which is directly bounded by a lateral surface (70) of the valve housing (66) on the inner circumferential side; ∘ an inlet opening (72) through which the secondary air can be introduced into the valve housing (66) and into the housing chamber (68); and ∘ an outlet opening (76) through which the secondary air from the valve housing (66) can be discharged to introduce the secondary air into the exhaust tract (22), and - a valve element (78) which can be moved, in a direction of movement (80), relative to the valve housing (66) between a closed position (S) which closes the outlet opening (76) and at least one open position (O) which releases the outlet opening (76), characterized in that: - the inlet opening (72) is arranged, in the direction of movement (80), between two sealing elements (90, 92) by means of which a lateral surface (94) of the valve element (78) on the outer circumferential surface and facing the lateral surface (70) on the inner circumferential surface is sealed off from the lateral surface (70) of the valve housing (66) on the inner circumferential surface; - the valve element (78) is designed as a plate-shaped or disk-shaped valve and has a plate-shaped or disk-shaped valve part (86) and a valve stem (88) to which the valve part (86) is connected; - the secondary air valve (64) has a third sealing element (96) by means of which, in the closed position (S), the valve part (86) is sealed off from the valve housing (66); and - the valve element (78) is free from a surface extending obliquely or perpendicularly to the direction of movement (80), at least on the outer circumferential side, along its entire extension (ER) which, at least in the closed position (S), extends, in the direction of movement (80), between the sealing elements (90, 92).

2. Secondary air valve (64) according to claim 1, characterized in that the valve element (78) is cylindrical, on the outer circumferential side, along its entire extension (ER) which, at least in the closed position (S), extends, in the direction of movement (80), between the sealing elements (90, 92).

3. Secondary air valve (64) according to claim 1 or claim 2, characterized in that the sealing elements (90, 92) are separate from one another and are spaced apart from one another in the direction of movement (80).

4. Secondary air valve (64) according to any of the preceding claims, characterized in that the sealing elements (90, 92) are held on the valve housing (66) so that the valve element (78) can be moved, in the direction of movement (80), relative to the valve housing (66) and relative to the sealing elements (90, 92) between the closed position (S) and the open position (O).

5. Secondary air valve (64) according to any of the preceding claims, characterized in that the inlet opening (72) has a passage direction (74) in which the inlet opening (72) can be flowed through by the air flowing into the valve housing (66) through the inlet opening (72), the passage direction (74) extending obliquely or perpendicularly to the direction of movement (80).

6. Internal combustion engine (10) for a motor vehicle, comprising a secondary air system (52) which has at least one secondary air valve (64) according to any of the preceding claims.

7. Internal combustion engine (10) according to claim 6, characterized in that the internal combustion engine (10) has: - the exhaust tract (22); and - an intake tract (20) through which air can flow and by means of which the air flowing through the intake tract (20) can be introduced into at least one combustion chamber (18) of the internal combustion engine (10), the secondary air system (52) having: ∘ a secondary air line (54) which is connected or can be connected fluidically to the intake tract (20) at a connection point (V) arranged upstream of the combustion chamber (18) so that at least a portion of the air flowing through the intake tract (20) can be diverted from the intake tract (20) at the connection point (V) by means of the secondary air line (54) and introduced into the exhaust tract (22) as secondary air, bypassing the combustion chamber (18); and ∘ the secondary air valve (64) which is arranged in the secondary air line (54).

8. Internal combustion engine (10) according to claim 7, characterized in that a compressor (28) for compressing the air flowing through the intake tract (20) is arranged in the intake tract (20), the connection point (V) being arranged downstream of the compressor (28).

9. Motor vehicle comprising an internal combustion engine (10) according to any of claims 6 to 8.