EP2077386A1 - Cylinder head with exhgaust manifold integrated in cylinder head - Google Patents

Abstract

The cylinder head has cylinders (1a-1c) with two outlets (2a, 2b) for discharging exhaust gas from the cylinder. Exhaust gas pipes (4a, 4b) are attached at the outlets. The pipes are combined to form an overall gas pipe (6) by formation of an exhaust manifold (13) within the head. A re-feeding pipe (7) is provided in the cylinder head for re-feeding the exhaust gas. The re-feeding pipe is branched out from the exhaust manifold and exhaust gas pipe parts (5a-5c), where a part of exhaust gas discharged from the cylinders is withdrawn from the manifold within the head.

Description

• jeder Zylinder mindestens zwei Auslaßöffnungen zum Abführen der Abgase aus dem Zylinder aufweist,
• sich an jede Auslaßöffnung eine Abgasleitung anschließt,
• die Abgasleitungen unter Ausbildung eines Abgaskrümmers innerhalb des Zylinderkopfes zu einer Gesamtabgasleitung zusammenführen, wobei zunächst die Abgasleitungen der mindestens zwei Auslaßöffnungen jedes Zylinders zu einer dem Zylinder zugehörigen Teilabgasleitung zusammenführen, bevor diese Teilabgasleitungen der mindestens zwei Zylinder zu der Gesamtabgasleitung zusammenführen.

The invention relates to a cylinder head with an at least partially integrated in the cylinder head coolant jacket for an internal combustion engine having at least two cylinders, in which

• each cylinder has at least two exhaust ports for exhausting the exhaust gases from the cylinder,
• adjoining each outlet opening an exhaust pipe,
• the exhaust pipes together to form an exhaust manifold within the cylinder head to merge an overall exhaust line, wherein first connect the exhaust pipes of the at least two exhaust ports of each cylinder to a cylinder associated with the partial exhaust line, before merging these partial exhaust gas lines of at least two cylinders to the entire exhaust line.

Furthermore, the invention relates to the use of such a cylinder head.

Internal combustion engines have a cylinder block and a cylinder head, which is used to form the individual cylinder d. H. Combustion chambers are interconnected.

The cylinder block has a corresponding number of cylinder bores for receiving the pistons or the cylinder tubes. The pistons are guided axially movably in the cylinder tubes and, together with the cylinder tubes and the cylinder head, form the combustion chambers of the internal combustion engine.

The cylinder head is often used to hold the valve train. In order to control the charge cycle, an internal combustion engine requires control means and actuators to operate these controls. As part of the change of charge, the expulsion of the combustion gases via the outlet openings and the filling of the combustion chamber that is the suction of the fresh mixture or the fresh air via the inlet openings takes place. For controlling the charge cycle, four-stroke engines use almost exclusively globe valves as control members, which oscillate during operation of the internal combustion engine Execute lifting movement and thus release the inlet and outlet openings and close. The required for the movement of the valves valve actuating mechanism including the valves themselves is referred to as a valve train.

It is the task of the valve train to open the intake and exhaust ports of the combustion chamber in time or close, with a quick release of the largest possible flow cross sections is sought to keep the throttle losses in the incoming and outflowing gas flows low and the best possible filling of the Combustion chamber with fresh mixture or an effective d. H. To ensure complete removal of the exhaust gases. Therefore, according to the prior art, two or more intake and exhaust ports are increasingly being provided as well as the cylinder head which is the subject of the present invention.

The inlet ducts leading to the inlet openings and the outlet ducts or exhaust ducts adjoining the outlet openings are at least partially integrated in the cylinder head according to the prior art. The exhaust pipes of the at least two exhaust ports of a single cylinder are often - within the cylinder head - merged into a cylinder associated partial exhaust gas line, these partial exhaust gas lines are then combined outside the cylinder to form a single overall exhaust line. The merging of the exhaust pipes to the entire exhaust line is referred to in general and in the context of the present invention as exhaust manifold or manifold.

Downstream of the manifold, the exhaust gases are then optionally supplied to the turbine of an exhaust gas turbocharger and / or one or more exhaust aftertreatment systems.

It is on the one hand endeavored to arrange the turbine as close to the outlet of the internal combustion engine, in order to make optimum use of the exhaust enthalpy of the hot exhaust gases and to ensure a rapid response of the turbocharger. On the other hand, the way the hot exhaust gases to the various exhaust aftertreatment systems should be as short as possible, so that the exhaust gases little time is granted for cooling and the exhaust aftertreatment systems as fast as possible Reach operating temperature or light-off temperature, in particular after a cold start of the internal combustion engine.

In this context, therefore, it is basically endeavored to minimize the thermal inertia of the portion of the exhaust pipe between exhaust port on the cylinder and exhaust aftertreatment system or between exhaust port on the cylinder and exhaust gas turbocharger, which can be achieved by reducing the mass and the length of this section.

In order to achieve the aforementioned objects, according to one prior art approach, the exhaust manifold is partially or fully integrated with the cylinder head. A cylinder head, in which connects to each outlet opening an exhaust pipe and merge the exhaust gas lines of the cylinder within the cylinder head to form an overall exhaust gas line, is the subject of the present invention.

Such a cylinder head is characterized by a very compact design, wherein the total distance traveled by the exhaust pipes of the exhaust manifold has been minimized. The use of such a cylinder head also leads to fewer components and consequently to a reduction in costs, in particular the assembly and deployment costs.

However, such a cylinder head is thermally loaded higher than a conventional cylinder head, which is equipped with an external manifold, and therefore makes increased demands on the cooling.

The heat released during combustion by the exothermic, chemical conversion of the fuel is partly dissipated via the walls delimiting the combustion chamber to the cylinder head and the cylinder block and partly via the exhaust gas flow to the adjacent components and the environment. In order to keep the thermal load of the cylinder head within limits, a portion of the introduced into the cylinder head heat flow must be withdrawn from the cylinder head again.

In principle, it is possible to carry out the cooling in the form of air cooling or liquid cooling. Due to the significantly higher heat capacity of liquids compared to air can be dissipated with the liquid cooling much larger amounts of heat than is possible with an air cooling.

The liquid cooling requires the equipment of the internal combustion engine or the cylinder head with a coolant jacket d. H. the arrangement of the coolant through the cylinder head leading coolant channels, which causes a complex structure of the cylinder head construction. In this case, the mechanically and thermally highly stressed cylinder head is weakened by the introduction of the coolant channels on the one hand in its strength. On the other hand, the heat must not be directed to the cylinder head surface as in the air cooling, to be dissipated. The heat is already in the interior of the cylinder head to the coolant, usually mixed with additives added water. The coolant is thereby conveyed by means of a pump arranged in the cooling circuit, so that it circulates in the coolant jacket. The heat given off to the coolant is removed in this way from the interior of the cylinder head and removed from the coolant in a heat exchanger again.

For these reasons, a coolant jacket is integrated in the cylinder head according to the prior art in a cylinder head of the present type.

A cylinder head with integrated exhaust manifold and integrated liquid cooling ie a cylinder head according to the preamble of claim 1 ie the generic type, for example, discloses the EP 1 722 090 A2 , as well as the registration EP 07110193.5 ,

Modern internal combustion engines are increasingly equipped with a cylinder head of the type in question. Increasingly, an exhaust gas recirculation is provided.

Exhaust gas recirculation, ie the recirculation of combustion gases from the exhaust gas side to the intake side of the internal combustion engine, has been identified as being expedient in order to comply with future limit values for pollutant emissions, in particular the limit values for nitrogen oxide emissions. Since the formation of nitrogen oxides requires not only an excess of air but also high temperatures, there is a concept for reducing nitrogen oxide emissions It is to develop combustion processes with lower combustion temperatures, wherein the exhaust gas recirculation is a means to lower the temperatures.

wobei m_AGR die Masse an zurückgeführtem Abgas und m_Frischluft die zugeführte und gegebenenfalls komprimierte Frischluft bzw. Ladeluft bezeichnet.With increasing exhaust gas recirculation rate, the nitrogen oxide emissions can be significantly reduced. The exhaust gas recirculation rate x _{EGR is} determined as follows: $${\mathrm{x}}_{\mathrm{AGR}}={\mathrm{m}}_{\mathrm{AGR}}/\left({\mathrm{m}}_{\mathrm{AGR}}/{\mathrm{m}}_{\mathrm{fresh\; air}}\right)$$

where m _AGR the mass of recirculated exhaust gas and m _fresh air refers to the supplied and optionally compressed fresh air or charge air.

Exhaust gas recirculation is also suitable for reducing emissions of unburned hydrocarbons in the partial load range.

In order to achieve a significant reduction in nitrogen oxide emissions, high exhaust gas recirculation rates are required, which can be on the order of x _AGR ≈ 50% to 70%.

In this case, the exhaust gas can basically be branched off downstream or upstream of an exhaust gas aftertreatment system provided on the exhaust side or of a turbine of an exhaust gas turbocharger, i. be removed.

If the exhaust gas branched off outside of the cylinder head, so that the tapping point for exhaust gas recirculation is arranged outside of the cylinder head, the line for returning the exhaust gas branches off from the total exhaust gas line as a rule. In this case, the return line must be connected to the entire exhaust line, for example by means of a flange connection. The joint is on the one hand a potential leakage point for the unwanted escape of exhaust gases, which implies high demands on the seal. On the other hand, this connection is thermally highly loaded by the hot exhaust gases, so that high demands are placed on the execution of the connection. If the entire exhaust line made of high temperature resistant material, the compound must also be made of costly and difficult to process material.

However, the prior art also includes concepts in which a line for exhaust gas recirculation is integrated into the cylinder head, wherein the return line branches off from an at least partially integrated in the cylinder head exhaust manifold.

The integrated into the cylinder head tapping point allows the one-piece design of manifold and return line d. H. the avoidance of training and sealing a non-positive connection point. Furthermore, the integration of the return line leads to a reduction in the number of components and a more compact design. The latter also supports the effort to achieve as dense as possible a packaging of the drive unit in the engine compartment.

A cylinder head with a built-in cylinder head tapping point for exhaust gas recirculation describes, for example, the GB 2 370 073 A , The return line branches off from a partial exhaust gas line of a cylinder with two outlet openings, wherein the first portion of the return line is employed against the flow direction of the exhaust gas in the used partial exhaust gas line, thus making it more difficult for exhaust gas to flow out of the associated cylinder. For the formation of this section also a special casting core must be provided, since the entire return line extends within the cylinder head and this section can not be formed in any other way, which makes the production difficult. In order to integrate the return line completely in the cylinder head, the cylinder head must also have the necessary material substance, which usually leads to an increase in weight.

The Indian GB 2 370 073 A described cylinder head also has an integrated only partially in the cylinder head exhaust manifold, so that the distance of the exhaust pipes and partial exhaust gas line to a possibly located outside of the cylinder head total exhaust gas line is comparatively long. This has the consequence that the return line is actually acted upon only with the exhaust gas of the individual cylinder or can be diverted from the partial exhaust gas line this line.

However, the exhaust gas of a single cylinder of a multi-cylinder internal combustion engine is insufficient to generate high return rates, which is why cylinder heads are provided must be able to achieve the high rates of return already mentioned above.

Against the background of the above, it is the object of the present invention to provide a cylinder head according to the preamble of claim 1, which is equipped with a built-in cylinder head tapping point for exhaust gas recirculation and with which the known prior art disadvantages are overcome and in particular high exhaust gas recirculation rates can be achieved.

Another object of the present invention is to show uses of such a cylinder head.

• jeder Zylinder mindestens zwei Auslaßöffnungen zum Abführen der Abgase aus dem Zylinder aufweist,
• sich an jede Auslaßöffnung eine Abgasleitung anschließt,
• die Abgasleitungen unter Ausbildung eines Abgaskrümmers innerhalb des Zylinderkopfes zu einer Gesamtabgasleitung zusammenführen, wobei zunächst die Abgasleitungen der mindestens zwei Auslaßöffnungen jedes Zylinders zu einer dem Zylinder zugehörigen Teilabgasleitung zusammenführen, bevor diese Teilabgasleitungen der mindestens zwei Zylinder zu der Gesamtabgasleitung zusammenführen,

und der dadurch gekennzeichnet ist, dass

• eine Leitung zur Rückführung von Abgas im Zylinderkopf vorgesehen ist, die von dem im Zylinderkopf integrierten Abgaskrümmer abzweigt und mit der zumindest ein Teil des aus den Zylindern abgeführten Abgases dem Abgaskrümmer innerhalb des Zylinderkopfes entnehmbar ist, wobei
• die Leitung zur Rückführung von Abgas von einer Teilabgasleitung abzweigt und aus dem Zylinderkopf austritt.

The first object is achieved by a cylinder head with an at least partially integrated in the cylinder head coolant jacket for an internal combustion engine with at least two cylinders, in which

• each cylinder has at least two exhaust ports for exhausting the exhaust gases from the cylinder,
• adjoining each outlet opening an exhaust pipe,
• first, connect the exhaust pipes of the at least two exhaust ports of each cylinder to a partial exhaust line associated with the cylinder, before these partial exhaust lines of the at least two cylinders merge to form the exhaust line, forming an exhaust manifold within the cylinder head;

and which is characterized in that

• a line is provided for the return of exhaust gas in the cylinder head, which branches off from the exhaust manifold integrated in the cylinder head and with which at least a portion of the exhaust gas discharged from the cylinders is removable from the exhaust manifold inside the cylinder head, wherein
• the line for returning exhaust gas branches off from a partial exhaust gas line and exits from the cylinder head.

The simultaneous combined integration of the exhaust manifold and the return line in the cylinder head leads to synergy effects in an advantageous manner.

The cylinder head according to the invention has - in contrast to that in the GB 2 370 073 A described cylinder head - via a fully integrated in the cylinder head exhaust manifold, which is why the distances of the individual exhaust pipes are comparatively short up to the total exhaust gas line. Due to the shorter flow paths, the return line for the individual partial exhaust gas streams of all cylinders or outlet openings is comparatively easily accessible. This advantageously leads to the fact that the return line diverging from the partial exhaust line of a single cylinder can be acted upon or acted upon by the exhaust gas of all the cylinders of the internal combustion engine.

The cylinder head according to the invention differs from concepts in which the cylinder head has an only partially integrated manifold, and also of concepts in which the return line branches off from the entire exhaust line or an exhaust pipe of a single outlet opening.

In the latter variant, a much more pronounced backflow of the exhaust components discharged from the other outlet openings would be required, but this does not occur in practice in this way or can not be realized, so that high return rates could not be realized with such a concept. In addition, a strong pulsation in the return line would be observed, since the return line would be acted upon substantially only with the exhaust gas of a single outlet opening.

On the other hand, the removal of the exhaust gas from the entire exhaust gas line would significantly increase the travel distance of the return line to be integrated into the cylinder head or complicate the routing of this return line. If necessary, this would require a substantial weight increase of the cylinder head, i. cause.

Thus, the first of the invention underlying subtask is solved, namely to provide a cylinder head of the generic type, with a cylinder head in the integrated tapping point is equipped for exhaust gas recirculation and can be achieved with the high exhaust gas recirculation rates.

Since the line for recycling the exhaust gas according to the invention and in contrast to that in the GB 2 370 073 A described cylinder head exiting from the cylinder head and consequently not the entire return line is integrated in the cylinder head, the production simplifies that means the formation of the branching off of the partial exhaust line section of the return line considerably. Thus, the return line - depending on the individual case - partially or completely be introduced by means of machining production process in the cylinder head blank.

The return line can also be partially or completely formed already during the casting of the cylinder head blank, which can be done by introducing a simple, outwardly open and therefore easily removable core.

In addition, there are more degrees of freedom in the production of the cylinder head. Thus, for example, a part of the return line can be formed during the casting of the cylinder head blank, the return line and the partial exhaust line remaining separated by an initially remaining wall. The subsequent removal of the wall then ensures the connection of the two lines. Ie. For a motor series, a uniform cylinder head blank can be made, in which can be selectively introduced by reworking a line for the return of exhaust gas or not.

Further advantageous embodiments of the cylinder head are discussed in connection with the subclaims.

Embodiments of the cylinder head in which the line for returning exhaust gas runs in a straight line are advantageous. The rectilinear design of the return line simplifies the production of the line considerably. A rectilinear return line can be formed for example in a simple manner by drilling.

In addition, a straight-line course can serve to shorten the length of the return line and thus to reduce the volume of the line. This in turn improves the response of the exhaust gas recirculation, which is considered to be advantageous.

Embodiments of the cylinder head in which the line for returning exhaust gas runs essentially parallel to the longitudinal axis of the cylinder head are advantageous. The return line usually connects laterally to the exhaust manifold and is not guided in the direction of the cylinder longitudinal axis up or down.

Embodiments of the cylinder head in which the line for recirculating exhaust gas to form a funnel-shaped inlet region adjoins the partial exhaust gas line are advantageous. In this embodiment, the diameter of the return line at the junction increases in the direction of the partial exhaust line, so that a funnel-shaped inlet region is formed, which supports the influx of exhaust gas, both the inflow from the cylinder, which is assigned to the partial exhaust gas line used for the return, and the inflow from the other cylinders. This is advantageous in particular with regard to the realization of high return rates.

Advantageously, sharp edges at which the exhaust gas flow breaks off or swirls are avoided. The cylinder head walls forming the partial exhaust gas line should preferably be continuous d. H. flow smoothly into the return line.

For this reason, embodiments of the cylinder head are also advantageous in which the walls of the conduit for returning exhaust gas to form the funnel-shaped inlet region bulge, whereby a trumpet-shaped inlet region is formed.

An inlet area which widens towards the partial exhaust gas line also leads to a reduction of the pulsation. If the inlet area to the partial exhaust gas line has curved, ie rounded, transitions, it is possible to influence the inflow conditions with the aid of the size of the radii of these rounded transitions. The use of different radii on the side facing away from the exhaust gas line on the one hand and On the other hand, on the side facing the overall exhaust gas line allows a targeted distribution of the exhaust gas streams used for the return.

Advantageous embodiments of the cylinder head, in which the line for recirculation of exhaust gas externally connected to the exhaust manifold.

This embodiment is advantageous because the cylinder head in this way only slightly by the introduction d. H. the integration of the return line is weakened or affected. In particular, the length of the return line is shortened, whereby the volume of the line is reduced, which - as already stated above - improves the response of the exhaust gas recirculation. Such a running return line also limits the interpretation of the cylinder head construction with respect to other requirements or functions as little as possible.

It should be noted in this context, in particular, that the cylinder head is anyway a thermally and mechanically highly loaded component, since the cylinder head already have a variety of tasks and functions. Thus, the cylinder head not only receives the valvetrain as described above, but also includes the bores into which the bolts for connecting the cylinder head to the cylinder block are inserted. Optionally, additional lines for venting the crankcase are provided in the cylinder head.

In addition, a cylinder head with integrated exhaust manifold has a comparatively bulky coolant jacket due to the high thermal load.

In general, a coolant jacket is introduced into the cylinder head, which has a lower coolant jacket, which is arranged between the exhaust pipes and the mounting end face of the cylinder head, and an upper coolant jacket, which is arranged on the side opposite the lower coolant jacket side of the exhaust pipes, wherein these two coolant jackets are additionally connected by means of passages.

Against this background, it is thus advantageous if the line for recirculation of exhaust gas has the smallest possible volume, which can be realized for example by the external connection of the return line to the exhaust manifold.

For the same reasons, embodiments in which the line for recirculating exhaust gas branches off from the partial exhaust line of an outer cylinder are also advantageous in internal combustion engines with three and more cylinders.

Furthermore, embodiments of the cylinder head in which the coolant jacket integrated in the cylinder head at least partially surrounds the line for returning exhaust gas are advantageous. In this way, the exhaust branched off from the exhaust manifold, provided for a return exhaust gas is already cooled in the cylinder head. The thermal load of a downstream of the return line or the tap point provided valve for controlling the return rate (EGR valve) and / or a seal decreases. An optionally provided additional radiator for cooling the recirculated exhaust gas may therefore be smaller in size.

The temperature of the cylinder fresh charge, which occurs in the mixture of fresh air with the recirculated exhaust gases, is consequently also reduced, which contributes to a better filling of the combustion chamber with fresh mixture. Increasing the density also reduces the volume, resulting in a decrease in flow losses.

Advantageously, the use of a cylinder head according to one of the aforementioned types, in particular in a supercharged internal combustion engine, since the exhaust gas recirculation and charging are often used in combination and a supercharged internal combustion engine is charged thermally higher.

Due to the cooling of the exhaust manifold and the return line in the cylinder head can be dispensed with the use of costly heat-resistant materials. This is due to the high exhaust gas temperatures, especially in supercharged internal combustion engines of relevance or advantage.

In addition, the dimensioning d. H. Determining the length of the exhaust ducts in supercharged internal combustion engines with respect to the combustion process of lesser importance than uncharged internal combustion engines, so that in turbocharged internal combustion engines, the generally short length of the cylinder head integrated manifold has no negative impact on the performance of the internal combustion engine.

The use of the cylinder head according to the invention is advantageous in particular in internal combustion engines that are charged by turbocharging. In these internal combustion engines, the turbine of the exhaust gas turbocharger is arranged in the overall exhaust line, thereby increasing the exhaust pressure upstream of the turbine and thus the exhaust pressure in the manifold, which in turn facilitates the introduction of the exhaust gas streams in the return line or reinforced, so that high return rates can be realized ,

Fig. 1

in einer Draufsicht den Gußkern der in einer ersten Ausführungsform des Zylinderkopfes integrierten Abgasleitungen mitsamt dem Gußkern für die integrierte Rückführleitung.

In the following the invention with reference to an embodiment according to the FIG. 1 described in more detail. Hereby shows:

Fig. 1

in a plan view of the casting core of the integrated in a first embodiment of the cylinder head exhaust pipes together with the casting core for the integrated return line.

FIG. 1 shows in a plan view of the casting core 12 of the integrated in a first embodiment of the cylinder head exhaust pipes 4a, 4b, 5a, 5b, 5c, 6, so that FIG. 1 per se, the system of integrated in the cylinder head exhaust pipes 4a, 4b, 5a, 5b, 5c, 6 itself illustrates or reproduces why the reference numerals for the exhaust pipes 4a, 4b, 5a, 5b, 5c, 6 were registered or used.

Shown is also provided in the cylinder head d. H. integrated line 7 for the return of exhaust gas or the casting core 11 used to form the return line 7.

At the in FIG. 1 illustrated casting core 12 and exhaust system is the exhaust pipes 4a, 4b, 5a, 5b, 5c, 6 of a cylinder head of a three-cylinder in-line engine.

Each of the three cylinders 1a, 1b, 1c is provided with two outlet openings 2a, 2b, with an exhaust pipe 4a, 4b for discharging the exhaust gases adjoining each outlet opening 2a, 2b.

The exhaust pipes 4a, 4b lead together to form an exhaust gas manifold 3 to form an overall exhaust gas line 6. The exhaust gas conduits 4a, 4b of each cylinder 1a, 1b, 1c initially lead to a partial exhaust gas line 5a, 5b, 5c associated with the cylinder 1a, 1b, 1c, these sub exhaust gas conduits 5a, 5b, 5c subsequently d. H. downstream open into a common total exhaust line 6. The exhaust gas leaves the cylinder head at the outlet 9 of the total exhaust line 6 from the cylinder head.

In the cylinder head, a line 7 for the return of exhaust gas is integrated. The return line 7 branches off from the exhaust manifold 3 integrated in the cylinder head, the return line 7 branching off from a partial exhaust line 5a of the manifold 3 and having an outlet 8 from the cylinder head.

At the in FIG. 1 illustrated embodiment, the rectilinear and parallel to the cylinder head longitudinal axis extending return line 7 branches off from the partial exhaust line 5a of an outer cylinder 1a, wherein the line 7 connects externally to the exhaust manifold 3.

The return line 7 connects to form a funnel-shaped inlet region 10 to the partial exhaust gas line 5a. In this case, the diameter of the return line 7 increases at the connection point in the direction of the partial exhaust gas line 5a. The inflow of exhaust gas is thereby simplified and that both the inflow from the cylinder 1 a, from the partial exhaust line 5 a, the return line 7 branches off, as well as the inflow from the other cylinders 1 b, 1 c.

The walls of the return line 7 bulge outwards in the direction of the partial exhaust gas line 5a, so that the inlet region 10 assumes a trumpet-shaped form.

Such a trained inlet region 10, which widens toward the partial exhaust gas line 5a, also leads to a reduction of the pulsation.

reference numeral

1a

cylinder

1b

cylinder

1c

cylinder

2a

outlet

2 B

outlet

3

exhaust manifold

4a

exhaust pipe

4b

exhaust pipe

5a

Part exhaust pipe

5b

Part exhaust pipe

5c

Part exhaust pipe

6

Total exhaust pipe

7

Line for recirculation of exhaust gas, return line

8th

Outlet of the return line from the cylinder head

9

Outlet of the entire exhaust line from the cylinder head

10

entry area

11

Cast core of the return line

12

Cast core of the exhaust manifold

Claims (10)

Cylinder head with an at least partially integrated in the cylinder head coolant jacket for an internal combustion engine having at least two cylinders (1 a, 1 b, 1 c), in which each cylinder (1a, 1b, 1c) has at least two outlet openings (2a, 2b) for discharging the exhaust gases from the cylinder (1a, 1b, 1c), - An exhaust pipe (4a, 4b) connects to each outlet opening (2a, 2b), - The exhaust pipes (4a, 4b) merge to form an exhaust manifold (3) within the cylinder head to an overall exhaust line (6), wherein first the exhaust pipes (4a, 4b) of the at least two outlet openings (2a, 2b) of each cylinder (1a, 1b , 1c) to a partial exhaust gas line (5a, 5b, 5c) associated with the cylinder (1a, 1b, 1c) before these partial exhaust gas lines (5a, 5b, 5c) of the at least two cylinders (1a, 1b, 1c) to the total exhaust gas line ( 6) merge characterized in that - A line (7) is provided for the return of exhaust gas in the cylinder head, which branches off from the integrated cylinder head exhaust manifold (3) and with the at least a portion of the cylinders (1a, 1b, 1c) exhaust discharged to the exhaust manifold (3) within the cylinder head is removable, wherein - The line (7) for returning exhaust gas from a partial exhaust gas line (5a, 5b, 5c) branches off and exits from the cylinder head. Cylinder head according to claim 1, characterized in that the conduit (7) for the return of exhaust gas is rectilinear. Cylinder head according to claim 1 or 2, characterized in that the line (7) for the return of exhaust gas extends substantially parallel to the longitudinal axis of the cylinder head. Cylinder head according to one of the preceding claims, characterized in that the line (7) for recirculation of exhaust gas with the formation of a funnel-shaped inlet region (10) to the partial exhaust gas line (5a, 5b, 5c) connects. Cylinder head according to claim 4, characterized in that the walls of the duct (7) for returning exhaust gas to the formation of the funnel-shaped inlet region (10) bulge. Cylinder head according to one of the preceding claims, characterized in that the line (7) for the return of exhaust gas externally connected to the exhaust manifold (3). Cylinder head according to one of the preceding claims for an internal combustion engine having at least three cylinders (1a, 1b, 1c), characterized in that the line (7) for recirculating exhaust gas from the partial exhaust pipe (5a, 5c) of an external cylinder (1a, 1c) branches. Cylinder head according to one of the preceding claims, characterized in that the coolant jacket integrated in the cylinder head at least partially surrounds the conduit (7) for the return of exhaust gas. Use of a cylinder head according to one of the preceding claims for a supercharged internal combustion engine. Use according to claim 9, characterized in that the internal combustion engine is charged by means of exhaust gas turbocharging.

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