V8 engine for a motor vehicle, and motor vehicle replacement

Abstract

The invention relates to a V8 engine (10) for a motor vehicle, the V8 engine comprising eight cylinders (1-8) which are arranged in two cylinder banks (16, 18) of four cylinders (1-4, 5-8) each in such a way that a first of the cylinder banks (16, 18) has a first one of the cylinders (1-8), a second one of the cylinders (1-8), a third one of the cylinders (1-8), and a fourth one of the cylinders (1-8). A second of the cylinder banks (16, 18) has a fifth one of the cylinders (1-8), a sixth one of the cylinders (1-8), a seventh one of the cylinders (1-8), and an eighth one of the cylinders (1-8). The cylinder banks (16, 18) are arranged next to one another along a straight line (22) extending perpendicularly to a viewing direction (20), the viewing direction (20) extending in the longitudinal direction (24) of the V8 engine (10) and from a front side (VS) of the V8 engine (10) towards an output side (AS) of the V8 engine (10) opposite the front side (VS) in the longitudinal direction (24) of the V8 engine (10).

Description

[0001] V8 engine for a motor vehicle and motor vehicle replacement

[0002] The invention relates to a V8 engine for a motor vehicle according to the preamble of patent claim 1. Furthermore, the invention relates to a motor vehicle with such a V8 engine.

[0003] DE 102018215 119 B3 discloses a V-type internal combustion engine having eight cylinders arranged in two banks of four cylinders each. Such an internal combustion engine is also known from DE 102017222 003 A1.

[0004] The object of the present invention is to provide a V8 engine for a motor vehicle and a motor vehicle so that a particularly advantageous noise behavior of the V8 engine can be realized.

[0005] This object is achieved by a V8 engine having the features of patent claim 1 and by a motor vehicle having the features of patent claim 7. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0006] A first aspect of the invention relates to a V8 engine for a motor vehicle, also simply referred to as a vehicle. This means that the motor vehicle, preferably designed as a motor vehicle, in particular as a passenger car, has the V8 engine in its fully manufactured state and can be driven by the V8 engine. The V8 engine is an internal combustion engine, also referred to as an internal combustion engine or combustion engine, with a V design, which is also referred to as a V-type. The V8 engine is a reciprocating piston machine, and therefore a reciprocating piston engine. The V8 engine has, in particular, exactly eight combustion chambers, as will be explained in more detail below.During fired operation of the V8 engine, which will also be referred to simply as the engine below, a respective combustion process takes place in the respective combustion chamber within a respective engine working cycle, during which a respective fuel-air mixture is ignited and thereby burned. In particular, the engine is a self-igniting internal combustion engine. The respective fuel-air mixture comprises air, also referred to as fresh air, and a fuel, in particular a liquid fuel. Preferably, the engine is designed as a car engine, so that the fuel is preferably a gasoline. The respective combustion process results in engine exhaust, the exhaust of which is also referred to as engine exhaust.

[0007] Each combustion chamber of the engine is partially defined by, in particular precisely, a respective cylinder, so that the V8 engine has, in particular precisely, eight cylinders. Since the respective igniter partially defines and thus forms the respective combustion chamber, the respective combustion process taking place in the respective combustion chamber within the respective working cycle takes place in the respective cylinder that partially defines the respective combustion chamber, so that the exhaust gas is created in the respective cylinder. The cylinder banks are also simply referred to as banks. The V8 engine is therefore an eight-cylinder engine with a V design. This means that the cylinder banks are arranged in a V-shape to one another, with the cylinder banks enclosing an angle different from 0 and 81°. This angle is understood in particular to be the smallest angle enclosed by the cylinder banks.In particular, the cylinder banks are arranged in a V-shape relative to one another when viewed in a plane, so that the cylinder banks form a V-shape in the plane, for example, which is simply referred to as a V. Thus, for example, the cylinder banks enclose the aforementioned angle in the plane. The plane is explained in more detail below.

[0008] The eight cylinders are arranged in the two cylinder banks of four cylinders each such that a first of the cylinder banks has, in particular, exactly four of the cylinders, namely a first of the cylinders, a second of the cylinders, a third of the cylinders and a fourth of the cylinders. Thus, for example, a second of the cylinder banks has, in particular, exactly four of the cylinders, namely a fifth of the cylinders, a sixth of the cylinders, a seventh of the cylinders and an eighth of the cylinders. The cylinder banks are arranged next to one another along a straight line perpendicular to the straight line, i.e. along a straight line running along a viewing direction in the longitudinal direction of the V8 engine and from a front of the V8 engine to an output side of the V8 engine opposite the front in the longitudinal direction of the V8 engine.The second cylinder bank is arranged to the right of the first cylinder bank when viewed in the direction of view. In other words, if a person standing in the vicinity of the V8 engine views the V8 engine in the direction of view mentioned, the second cylinder bank is arranged to the right of the first cylinder bank for that person along the straight line running perpendicular to the direction of view. On the output side, the V8 engine can be coupled to a transmission of the motor vehicle in a torque-transmitting manner, so that the motor vehicle can be driven by the V8 engine via the transmission. This means that the V8 engine has a coupling device on its output side, by means of which the V8 engine on the output side can be or is coupled to the transmission in a torque-transmitting manner.For this purpose, the transmission comprises, for example, a clutch designed as a friction clutch or as a hydrodynamic torque converter, to which, for example, the V8 engine is or can be coupled via the coupling device in a torque-transmitting manner. This means in particular that the V8 engine can provide drive torque on the output side, by means of which the motor vehicle can be driven, wherein the respective drive torque can be or is dissipated by the V8 engine on the output side in order to thereby drive the motor vehicle. For example, the front side is a control side, on which a control drive of the V8 engine is arranged, designed, for example, as a chain drive, belt drive or gear drive. The V8 engine has, for example, an output shaft which can be rotated about a drive shaft axis of rotation relative to the cylinder banks.The V8 engine can provide the aforementioned drive torque via its output shaft. For example, a valve train can be driven from the output shaft via the timing drive, which has gas exchange valves assigned to the combustion chamber and thus to the cylinders.

[0009] The first cylinder, the second cylinder, the third cylinder, and the fourth cylinder are arranged in the following initial sequence, i.e., one after the other, in the viewing direction: the first cylinder - the second cylinder - the third cylinder - the fourth cylinder. Thus, for the person viewed in the viewing direction, the second cylinder is arranged relative to the first cylinder and the third cylinder, and the third cylinder is arranged relative to the second cylinder and the fourth cylinder. The first cylinder would also be designated 1, the second cylinder 2, the third cylinder 3, and the fourth cylinder 4.

[0010] The fifth cylinder, the sixth cylinder, the seventh cylinder, and the eighth cylinder are arranged one after the other in the viewing direction in the following second order: the fifth cylinder - the sixth cylinder - the seventh cylinder - the eighth cylinder. Thus, for the person viewed in the viewing direction, the sixth cylinder is arranged between the fifth cylinder and the seventh cylinder, and the seventh cylinder is arranged next to the sixth cylinder and the eighth cylinder. The fifth cylinder is also designated 5, the sixth cylinder also 6, the seventh cylinder also 7, and the eighth cylinder also 8. In particular, the first, second, third, and fourth cylinders are arranged one after the other along a first viewing line in the first order, wherein the first viewing line runs parallel to the viewing direction and thus in the longitudinal direction of the V8 engine.In particular, the fifth, sixth, seventh, and eighth cylinders are arranged consecutively along a second viewing line, with the second viewing line running parallel to the first viewing line and thus parallel to the viewing direction and parallel to the longitudinal direction, i.e., in the longitudinal direction of the V8 engine. The longitudinal direction of the V8 engine coincides with the output shaft rotation axis.

[0011] The combustion chamber partially bounded by the first cylinder was also called the first combustion chamber, the combustion chamber partially bounded by the second cylinder was also called the second combustion chamber, the combustion chamber partially bounded by the third cylinder is also called the third combustion chamber, the combustion chamber partially bounded by the fourth cylinder is also called the fourth combustion chamber, the combustion chamber partially bounded by the fifth cylinder is also called the fifth combustion chamber, the combustion chamber partially bounded by the sixth cylinder is also called the sixth combustion chamber, the combustion chamber partially bounded by the seventh cylinder is also called the seventh combustion chamber and the combustion chamber partially bounded by the eighth cylinder is also called the eighth combustion chamber.

[0012] The V8 engine has an exhaust tract through which the exhaust gas from the V8 engine can flow. The exhaust tract has at least one first exhaust outlet assigned to the first cylinder, via which the exhaust gas from the V8 engine can be discharged from the first cylinder and thus from the first combustion chamber. The exhaust tract has at least one second exhaust outlet assigned to the second cylinder, via which the exhaust gas from the V8 engine can be discharged from the second cylinder and thus from the second combustion chamber. The exhaust tract has at least one third exhaust outlet assigned to the third cylinder and thus to the third combustion chamber, via which the exhaust gas from the third cylinder and thus from the third combustion chamber can be discharged. The exhaust tract has at least one fourth exhaust outlet assigned to the fourth cylinder, via which the exhaust gas from the fourth cylinder and thus from the fourth combustion chamber can be discharged.The exhaust tract has at least one fifth exhaust outlet assigned to the fifth cylinder and thus to the fifth combustion chamber, via which the exhaust gas of the V8 engine can be discharged from the fifth cylinder and thus from the fifth combustion chamber. The exhaust tract has at least one sixth exhaust outlet assigned to the sixth cylinder, via which the exhaust gas of the V8 engine can be discharged from the sixth cylinder and thus from the sixth combustion chamber. The exhaust tract has at least one seventh exhaust outlet assigned to the seventh cylinder and thus to the seventh combustion chamber, via which the exhaust gas of the V8 engine can be discharged from the seventh cylinder and thus from the seventh combustion chamber. Furthermore, the exhaust tract has at least one eighth exhaust outlet assigned to the eighth cylinder and thus to the eighth combustion chamber, via which the exhaust gas of the V8 engine can be discharged from the eighth cylinder and thus from the eighth combustion chamber.For example, the respective exhaust gas outlet is or comprises, in particular precisely, a respective exhaust channel which is formed or delimited, for example, in particular directly, by a respective cylinder head.

[0013] The V8 engine has a first exhaust gas turbocharger and a second exhaust gas turbocharger provided in addition to the first exhaust gas turbocharger, so that the V8 engine is designed, for example, as a bi-turbo engine. The first exhaust gas turbocharger has a first turbine arranged in the exhaust tract. The second exhaust gas turbocharger has a second turbine arranged in the exhaust tract and provided in addition to the first turbine. The first turbine has, for example, a first turbine housing and a first turbine wheel, which is arranged in the first turbine housing and is rotatable about a first impeller axis of rotation relative to the first turbine housing. The second turbine has, for example, a second turbine housing and a second turbine wheel, which is arranged, for example, in the second turbine housing and is rotatable about a second impeller axis of rotation relative to the second turbine housing.

[0014] Preferably, impeller rotation axes are spaced apart from one another, wherein the impeller rotation axes preferably run parallel to one another.

[0015] In order to be able to achieve particularly advantageous noise behavior of the V8 engine, in particular during fired operation of the V8 engine, the invention provides that the first exhaust outlet and the third exhaust outlet are merged, i.e. combined, to form a first exhaust line running in the exhaust tract in the flow direction of the exhaust gas flowing through the exhaust tract upstream of the first turbine. During fired operation of the V8 engine, the exhaust gas flows through the exhaust tract in the said flow direction. The first turbine, i.e. the first turbine wheel, can be supplied with the exhaust gas flowing through the first exhaust line from the first cylinder and the third cylinder via the first exhaust line, such that the first turbine can be driven by the exhaust gas from the first cylinder and the third cylinder.The second exhaust outlet and the fifth exhaust outlet are combined or joined to form a second exhaust line running upstream of the first turbine in the exhaust system with respect to the flow direction of the exhaust gas of the V8 engine flowing through the exhaust system, wherein the first turbine, i.e., the first turbine wheel, can be supplied with the exhaust gas flowing through the second exhaust line from the second cylinder and the fifth cylinder via the second exhaust line. As a result, the first turbine wheel can be driven by the exhaust gas from the second cylinder and the fifth cylinder. For example, the first exhaust line and the second exhaust line run at least partially separately from one another.

[0016] The sixth exhaust outlet and the eighth exhaust outlet are combined to form a third exhaust line in the exhaust system, which runs upstream of the second turbine in relation to the flow direction of the exhaust gas flowing through the exhaust system. Via this third exhaust line, the second turbine, i.e., the second turbine wheel, can be supplied with the exhaust gas flowing through the third exhaust line from the sixth cylinder and the eighth cylinder. Thus, the second turbine wheel can be driven by the exhaust gas from the sixth cylinder and the eighth cylinder.In addition, the seventh exhaust outlet and the fourth exhaust outlet are combined or joined to form a fourth exhaust line in the exhaust tract, which runs upstream of the second turbine with respect to the flow direction of the exhaust gas flowing through the exhaust tract, wherein the second turbine, i.e. the second turbine wheel, can be supplied with the exhaust gas flowing through the fourth exhaust line from the seventh cylinder and the fourth cylinder via the fourth exhaust line. The second turbine wheel can therefore also be driven by the exhaust gas from the seventh cylinder and the fourth cylinder. In particular, the invention makes it possible to generate the typical so-called V8 bubbling sound during fired operation of the V8 engine, so that the V8 engine produces a particularly pleasant and powerful sound for a person in the vicinity of the V8 engine, particularly during fired operation. At the same time, particularly efficient operation of the V8 engine can be achieved.

[0017] In order to be able to realize a particularly advantageous noise behavior, it is provided in one embodiment of the invention that in the installation position of the V8 engine, which assumes an installation position in the completely manufactured state of the motor vehicle having the V8 engine, and with respect to a viewing direction of a person viewing the motor vehicle in the longitudinal direction of the motor vehicle from front to rear, the viewing direction corresponds to the viewing direction.

[0018] In order to be able to generate a particularly advantageous sound pattern, and in particular the typical V8 burble, a further embodiment of the invention provides for the V8 engine to have the following firing order: first cylinder - fifth cylinder - fourth cylinder - eighth cylinder - third cylinder - seventh cylinder - second cylinder - sixth cylinder. In other words, the firing order of the V8 engine, also known as the firing sequence, is preferably:

[0019] 1-5-4-8-3-7-2-6

[0020] The ignition sequence means that within the respective working cycle of the V8 engine during fired operation of the V8 engine, first, i.e. with regard to the eight cylinders, the mixture in the first cylinder is ignited, then the mixture in the fifth cylinder, then the mixture in the fourth cylinder, then the mixture in the eighth cylinder, then the mixture in the third cylinder, then the mixture in the seventh cylinder, then the mixture in the second cylinder and, in particular, lastly, the mixture in the sixth cylinder.

[0021] A further embodiment is characterized in that the aforementioned angle enclosed by the cylinder banks, also referred to as the cylinder bank angle, lies in a range from 80° to 0°, in particular 90°. This allows for particularly advantageous noise behavior.

[0022] In order to achieve particularly advantageous noise characteristics and particularly efficient operation of the V8 engine, a further embodiment of the invention provides that the turbines are each arranged at least partially between the cylinder banks, viewed along the straight line, and are each at least partially overlapped by the respective cylinder bank, viewed along the straight line toward the respective cylinder bank. As a result, the turbines are arranged in the aforementioned V, so to speak, which is also referred to as the hot V, which lies between the cylinder banks, viewed along the straight line.

[0023] Finally, to achieve particularly favorable noise characteristics and particularly efficient operation of the V8 engine, it has proven particularly advantageous if a respective piston is mounted in each cylinder so that it can move translationally. The pistons are pivotally coupled to the output shaft of the V8 engine, so that the translational movements of the piston can be converted into a rotational movement of the output shaft around the output shaft's axis of rotation and relative to the respective cylinder bank. The output shaft is designed as a flat-plane crankshaft, also known as a flat crankshaft, flat crankshaft, or flat-plane crankshaft.

[0024] The previously mentioned plane runs perpendicular to the viewing direction, thus perpendicular to the longitudinal direction and perpendicular to the output shaft rotation axis.

[0025] The pre-plane crankshaft is characterized in that, in particular, all the crankpins of the output shaft, also referred to as the crankshaft, are arranged in pairs offset by 180° from one another, in particular when viewed in the circumferential direction of the output shaft extending around the output shaft's axis of rotation and, in particular, the aforementioned plane. Thus, in particular, all the crankpins of the output shaft are arranged in an arrangement plane in which the longitudinal direction and the output shaft's axis of rotation extend, so that the arrangement plane is perpendicular to the aforementioned plane. The invention is based in particular on the following findings and considerations:

[0026] Compared to a cross-plane crankshaft, also known as a cross-plane crankshaft, a flat-plane crankshaft is typically disadvantageous in terms of generating the typical V8 burble, meaning that a flat-plane crankshaft cannot typically produce as pronounced a V8 burble as a cross-plane crankshaft. However, the use of a flat-plane crankshaft has the advantage over a cross-plane crankshaft that, especially in combination with the hot V, a more even fresh air charge can be achieved, which can lead to better or higher performance and reduced exhaust emissions.Compared to the crossplane crankshaft, the flatplane crankshaft has disadvantages in terms of sound, particularly with regard to the generation of the typical V8 burble. This is because the use of a flatplane crankshaft usually results in a symmetrical alternation of exhaust gas flows into the exhaust tract, also known as the exhaust system. As a result, the exhaust noise resembles two four-cylinder engines running in parallel. This means that the typical V8 burble cannot be generated at idle, for example, and even when revving, a sound characteristic is created that could be considered less advantageous than a V8 engine with a crossplane crankshaft. However, the aforementioned disadvantages can now be avoided by the invention.The described merging of the exhaust outlets and thus the cylinders creates a cross-bank merging of the exhaust outlets and thus the cylinders, so that, despite the use of the flat-plane crankshaft, a particularly advantageous noise behavior of the V8 engine according to the invention can be achieved, in particular such that, for example, the V8 engine exhibits the typical V8 burbling when idling. At the same time, due to the use of the flat-plane crankshaft, an advantageously high specific power can be achieved, and particularly low-emission operation of the V8 engine can be achieved. In other words, disadvantages of a V8 engine with a cross-plane crankshaft with regard to power and exhaust emissions can thus be at least almost completely avoided.By combining the exhaust outlets and thus the cylinders as provided according to the invention, a certain irregularity is deliberately created in an exhaust gas flow formed by the exhaust gas across the two cylinder banks, whereby a V8-typical sound pattern can be realized, particularly in a muzzle noise of the exhaust tract.

[0027] A second aspect of the invention relates to a motor vehicle, also referred to simply as a vehicle and preferably designed as a motor vehicle, in particular a passenger car, which has a V8 engine according to the first aspect of the invention and is drivable by means of the V8 engine. 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.

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

[0029] The drawing shows, in the sole Fig. 1, a schematic representation of an internal combustion engine designed as a V8 engine for a motor vehicle. Fig. 1 shows, in a schematic representation, an internal combustion engine designed as a V8 engine 10 for a motor vehicle, also simply referred to as a vehicle. The V8 engine is designed as a reciprocating piston engine. The V8 engine has, in particular, exactly eight combustion chambers, namely a first combustion chamber, a second combustion chamber, a third combustion chamber, a fourth combustion chamber, a fifth combustion chamber, a sixth combustion chamber, a seventh combustion chamber, and an eighth combustion chamber.During fired operation of the V8 engine, which is also simply referred to as the engine, a respective combustion process takes place in the respective combustion chamber within a respective engine working cycle, in which a respective fuel-air mixture, which is also simply referred to as the mixture, is combusted, in particular ignited and burned. The respective mixture comprises fresh air, also simply referred to as air, and a preferably liquid fuel. The combustion of the respective mixture results in an exhaust gas from the engine, also referred to as engine exhaust. The respective combustion chamber is partially delimited by a respective cylinder of the engine, so that the engine has, in particular, exactly eight cylinders, namely a first cylinder 1, a second cylinder 2, a third cylinder 3, a fourth cylinder 4, a fifth cylinder 5, a sixth cylinder 6, a seventh cylinder 7 and an eighth cylinder 8.The first cylinder 1 partially delimits the first combustion chamber, the second cylinder 2 the second combustion chamber, the third cylinder 3 the third combustion chamber, the fourth cylinder 4 the fourth combustion chamber, the fifth cylinder 5 the fifth combustion chamber, the sixth cylinder 6 the sixth combustion chamber, the seventh cylinder 7 the seventh combustion chamber and the eighth cylinder 8 the eighth combustion chamber each partially delimiting. In the respective cylinder 1-8, a respective piston is accommodated so as to be translationally movable, the respective piston partially delimiting the respective combustion chamber, which is delimited by the respective cylinder 1-8 in which the respective piston is accommodated so as to be translationally movable.The pistons are articulated, in particular via connecting rods, to an output shaft 12 of the engine designed as a crankshaft, so that the translational movements of the pistons can be converted into a rotational movement of the output shaft 12 running around an output shaft rotation axis 14.

[0030] The eight cylinders 1-8 are arranged in two cylinder banks 16, 18, each comprising four cylinders, in particular separately formed from one another, such that the first cylinder bank 16 has cylinders 1-4 and the second cylinder bank 18 has cylinders 5-8. The cylinder banks 16, 18 are arranged next to one another along a first straight line 22 running perpendicular to the viewing direction, illustrated by an arrow 20, with respect to a viewing direction running in the longitudinal direction of the V8 engine 10 and from a front side VS of the engine to an output side AS of the engine opposite the front side VS in the longitudinal direction of the engine. The viewing direction 20 runs along a second straight line 24, which runs perpendicular to the first straight line 22 and coincides with the output shaft axis of rotation 14. The output shaft 12 is rotatable about the output shaft axis of rotation 14 relative to the cylinder banks 16, 18.Due to the articulated coupling of the pistons with the output shaft 12, the translational movements of the pistons can be converted into the aforementioned rotational movement of the output shaft 12 around the output shaft axis of rotation and relative to the cylinder banks 16, 18.

[0031] Relative to the viewing direction (arrow 20), i.e. for a person viewing the V8 engine 10 in the viewing direction and thus in the longitudinal direction of the V8 engine 10 from the front VS to the output side AS, and located in an area 26 of the engine, the cylinder bank 18 is arranged along the straight line 22 to the right of the cylinder bank 16. Furthermore, cylinders 1-4 are arranged consecutively in the viewing direction in the following first order, i.e. one behind the other: 1-2-3-4. Furthermore, cylinders 5-8 are arranged consecutively in the viewing direction in the following second order: 5-6-7-8.It can be seen that cylinders 1-4 are arranged sequentially along a first viewing line and cylinders 5-8 along a second viewing line in the respective stated order, wherein the viewing lines are spaced apart from one another along the straight line 22, run perpendicular to the straight line 22, and run parallel to the second straight line 24 and thus to the longitudinal direction of the V8 engine 10. The longitudinal direction of the V8 engine 10, like the stated viewing direction (arrow 20), runs straight, thus along the straight line 24, wherein the viewing direction and the longitudinal direction of the V8 engine 10 coincide with the output shaft rotation axis 14.

[0032] On the output side AS, in particular when the motor vehicle is fully assembled, a respective drive torque provided or can be provided by the engine via the output shaft 12 and intended to drive the motor vehicle can be or will be discharged from the output shaft 12 and introduced or introduced, for example, into a transmission of the motor vehicle. The output shaft 12 is, for example, coupled on the output side AS to the transmission, in particular to a clutch of the transmission, in a torque-transmitting manner. For example, a timing drive is arranged on the front side VS, via which a valve drive can be actuated from the output shaft 12, by means of which gas exchange valves assigned to cylinders 1-8 and thus to the combustion chambers can be actuated.

[0033] The V8 engine 10 has an exhaust tract 28 through which the engine's exhaust gas flows, also referred to as an exhaust system. At least one exhaust outlet 30a-h of the exhaust tract 28 is assigned to each cylinder 1-8 and each combustion chamber. The exhaust gas from the respective cylinder 1-8, to which the respective exhaust outlet 30a-h is assigned, can be discharged via the respective exhaust outlet 30a-h and thus introduced into the exhaust tract 28. The exhaust gas can then flow through the exhaust tract 28.

[0034] It can also be seen that the V8 engine 10 has a first exhaust gas turbocharger 32 and a second exhaust gas turbocharger 34. The exhaust gas turbocharger 32 has a first turbine 36 arranged in the exhaust tract 28 and having a first turbine wheel 38. The exhaust gas turbocharger 34 has a second turbine 40 arranged in the exhaust tract 28 and having a second turbine wheel 42. The respective exhaust gas turbocharger 32, 34 has a respective compressor 44, 46 with a respective compressor wheel 48, 50. The compressor wheel 48 can be driven by the turbine wheel 38 driving the turbine wheel 38. The compressor wheel 50 can be driven by the turbine wheel 42 driving the turbine wheel 42. The aforementioned fresh air can be compressed by means of the compressor wheels 48 and 50, thus by means of the compressors 44 and 46. The turbine wheels 38 and 42, and thus the turbines 36 and 40, are driven by the exhaust gas, so that the energy contained in the exhaust gas can be used to compress the fresh air.

[0035] In order to be able to realize a particularly advantageous noise behavior of the V8 engine, the first exhaust outlet 30a and the third exhaust outlet 30c are brought together, that is to say combined, to form a first exhaust line A1 which runs in the exhaust tract 28 in the flow direction of the exhaust gas flowing through the exhaust tract 28 upstream of the first turbine 36, that is to say upstream of the turbine wheel 38, via which the first turbine 36, that is to say the first turbine wheel 38, can be supplied with the exhaust gas from the cylinders 1, 3 flowing through the first exhaust line A1.The second exhaust outlet 30b and the fifth exhaust outlet 30e are combined, i.e., joined, to form a second exhaust line A2, which runs upstream of the first turbine 36, i.e., upstream of the turbine wheel 38, in the exhaust tract 28 in the flow direction of the exhaust gas flowing through the exhaust tract 28. Via this second exhaust line, the first turbine 36, i.e., the first turbine wheel 38, can be supplied with the exhaust gas flowing through the second exhaust line A2 from cylinders 2, 5. Thus, the turbine wheel 38 can be driven by the exhaust gas from cylinders 1, 3, 2, 5.The sixth exhaust outlet 30f and the eighth exhaust outlet 30h are combined to form a third exhaust line A3 which runs in the exhaust tract 28 in the flow direction of the exhaust gas flowing through the exhaust tract 28 upstream of the second turbine 40 and thus upstream of the second turbine wheel 42, via which the second turbine 40, i.e. the second turbine wheel 42, can be supplied with the exhaust gas flowing through the third exhaust line A3 from the cylinders 6, 8. In addition, the seventh exhaust outlet 30g and the fourth exhaust outlet 30d are combined to form a fourth exhaust line A4 which runs in the exhaust tract 28 in the flow direction of the exhaust gas flowing through the exhaust tract 28 upstream of the second turbine 40, that is to say upstream of the turbine wheel 42, via which the second turbine 40, that is to say the second turbine wheel 42, can be supplied with the exhaust gas flowing through the fourth exhaust line A4 from the cylinders 7, 4.Thus, the turbine wheel 42 can be driven by the exhaust gas from cylinders 6, 8, 7 and 4.

[0036] The V8 engine preferably has the following firing order: 1-5-4-8-3-7-2-6. This makes it possible to achieve particularly advantageous noise behavior. Viewed in the aforementioned plane, the cylinder banks 16 and 18 are arranged in a V-shape relative to one another, so that the cylinder banks 16 and 18, viewed in the aforementioned plane, form a V-shape, simply referred to as a V, particularly between them, such that the cylinder bank 16 is a first leg of the V-shape and the cylinder bank 18 is a second leg of the V-shape. The legs, and therefore the cylinder banks 18, enclose an angle, also referred to as the cylinder bank angle, which is preferably 90°. The angle is the smallest angle enclosed by the cylinder banks or legs. The turbines 36 and 40 are arranged in the V, which is also referred to as the hot V because it lies between the cylinder banks 16 and 18.

[0037] In order to achieve particularly advantageous noise characteristics and particularly low-emission operation of the V8 engine, it is also provided that the output shaft 12, designed as a crankshaft, is designed as a flat-plane crankshaft, which is also referred to as a flat-plane crankshaft.

[0038] 1 first cylinder

[0039] 2 second cylinder

[0040] 3 third cylinder

[0041] 4 fourth cylinder

[0042] 5 fifth cylinder

[0043] 6 sixth cylinder

[0044] 7 seventh cylinder

[0045] 8 eighth cylinder

[0046] 10 V8 engine

[0047] 12 Output shaft

[0048] 14 Output shaft rotation axis

[0049] 16 first cylinder bank

[0050] 18 second cylinder bank

[0051] 20 Arrow

[0052] 22 first straight

[0053] 24 second straight

[0054] 26 Surroundings

[0055] 28 Exhaust system

[0056] 30a-h exhaust outlet

[0057] 32 first exhaust gas turbocharger

[0058] 34 second exhaust turbocharger

[0059] 36 first turbine

[0060] 38 first turbine wheel

[0061] 40 second turbine

[0062] 42 second turbine wheel

[0063] 44 compressors

[0064] 46 compressors

[0065] 48 Compressor wheel

[0066] 50 compressor wheel

[0067] A1 first exhaust pipe

[0068] A2 second exhaust pipe

[0069] A3 third exhaust pipe

[0070] A4 fourth exhaust pipe

[0071] AS output side

[0072] VS front

Claims

Patent claims 1. V8 engine (10) for a motor vehicle, comprising: - eight cylinders (1-8) which are arranged in two cylinder banks (16, 18) of four cylinders each (1-4, 5-8) such that: o a first of the cylinder banks (16, 18) has a first of the cylinders (1-8), a second of the cylinders (1-8), a third of the cylinders (1-8) and a fourth of the cylinders (1-8); o a second of the cylinder banks (16, 18) has a fifth of the cylinders (1-8), a sixth of the cylinders (1-8), a seventh of the cylinders (1-8) and an eighth of the cylinders (1-8); o the cylinder banks (16, 18) are arranged next to one another along a straight line (22) running perpendicular to the viewing direction (20) with respect to a viewing direction (20) running in the longitudinal direction (24) of the V8 engine (10) and from a front side (VS) of the V8 engine (10) to an output side (AS) of the V8 engine (10) opposite the front side (VS) in the longitudinal direction (24) of the V8 engine (10);o the second cylinder bank (18) is arranged to the right of the first cylinder bank (16) with respect to the viewing direction (20); o the first cylinder (1), the second cylinder (2), the third cylinder (3) and the fourth cylinder (4) are arranged successively in the viewing direction (20) in the following first order: the first cylinder (1) - the second cylinder (2) - the third cylinder (3) - the fourth cylinder (4); and o the fifth cylinder (5), the sixth cylinder (6), the seventh cylinder (7) and the eighth cylinder (8) are arranged successively in the viewing direction (20) in the following second order: the fifth cylinder (5) - the sixth cylinder (6) - the seventh cylinder (7) - the eighth cylinder (8); - an exhaust tract (28) which comprises: o at least one first exhaust outlet (30a) assigned to the first cylinder (1), via which exhaust gas from the V8 engine (10) can be discharged from the first cylinder (1); o at least one second exhaust outlet (30b) assigned to the second cylinder (2), via which exhaust gas from the V8 engine (10) can be discharged from the second cylinder (2); o at least one third exhaust outlet (30c) assigned to the third cylinder (3), via which exhaust gas from the V8 engine (10) can be discharged from the third cylinder (3); o at least one fourth exhaust outlet (30d) assigned to the fourth cylinder (4), via which exhaust gas from the V8 engine (10) can be discharged from the fourth cylinder (4); o at least one fifth exhaust outlet (30e) assigned to the fifth cylinder (5), via which exhaust gas from the V8 engine (10) can be discharged from the fifth cylinder (5); o at least one sixth exhaust outlet (30f) associated with the sixth cylinder (6), via which exhaust gas of the V8 engine (10) can be discharged from the sixth cylinder (6);o at least one seventh exhaust outlet (30g) associated with the seventh cylinder (7), via which exhaust gas from the V8 engine (10) can be discharged from the seventh cylinder (7); and o at least one eighth exhaust outlet (30h) associated with the eighth cylinder (8), via which exhaust gas from the V8 engine (10) can be discharged from the eighth cylinder (8); - a first exhaust gas turbocharger (32) with a first turbine (36) arranged in the exhaust tract (28); and - a second exhaust gas turbocharger (34) with a second turbine (40) arranged in the exhaust tract (28); characterized in that: - the first exhaust gas outlet (30a) and the third exhaust gas outlet (30c) are combined to form a first exhaust gas line (A1) running upstream of the first turbine (36) in the exhaust gas tract (28), via which first exhaust gas line the first turbine (36) can be supplied with the exhaust gas flowing through the first exhaust gas line (A1) from the first cylinder (1) and the third cylinder (3); - the second exhaust gas outlet (30b) and the fifth exhaust gas outlet (30e) are combined to form a second exhaust gas line (A2) running upstream of the first turbine (36) in the exhaust gas tract (28), via which second exhaust gas line the first turbine (36) can be supplied with the exhaust gas flowing through the second exhaust gas line (A2) from the second cylinder (2) and the fifth cylinder (5); - the sixth exhaust outlet (30f) and the eighth exhaust outlet (30h) are combined to form a third exhaust line (A1) running in the exhaust tract (28) upstream of the second turbine (40), via which the second turbine (40) can be supplied with the exhaust gas flowing through the third exhaust line (A3) from the sixth cylinder (6) and the eighth cylinder (8); and - the seventh exhaust outlet (30g) and the fourth exhaust outlet (30d) are combined to form a fourth exhaust line (A4) running in the exhaust tract (28) upstream of the second turbine (40), via which fourth exhaust line the second turbine (40) can be supplied with the exhaust gas flowing through the fourth exhaust line (A4) from the seventh cylinder (7) and the fourth cylinder (4).

2. V8 engine (10) according to claim 1, characterized in that in the installed position of the V8 engine (109) and with respect to a viewing direction of a person viewing the motor vehicle in the longitudinal direction of the motor vehicle from front to rear, the viewing direction (20) corresponds to the viewing direction.

3. V8 engine (10) according to claim 1 or 2, characterized in that the V8 engine (10) has the following firing order: first cylinder (1) - fifth cylinder (5) - fourth cylinder (4) - eighth cylinder (8) - third cylinder (3) - seventh cylinder (7) - second cylinder (2) - sixth cylinder (6).

4. V8 engine (10) according to one of the preceding claims, characterized in that a cylinder bank angle enclosed by the cylinder banks (16, 18) lies in a range from 80 degrees to 100 degrees inclusive.

5. V8 engine (10) according to one of the preceding claims, characterized in that the turbines (36, 40) viewed along the straight line (22) each have at least partially arranged between the cylinder banks (16, 18) and, viewed along the straight line (22) towards the respective cylinder bank (16, 18), are each at least partially overlapped by the respective cylinder bank (16, 18).

6. V8 engine (10) according to one of the preceding claims, characterized in that a respective piston is accommodated in the respective cylinder (1-8) so as to be translationally movable, wherein the pistons are articulatedly coupled to an output shaft (12) of the V8 engine (10), the output shaft (12) of which is designed as a flat-plane crankshaft.

7. Motor vehicle with a V8 engine (10) according to one of the preceding claims, wherein the motor vehicle can be driven by means of the V8 engine (10).

Images