DE102022101656A1 - Exhaust gas recirculation cooler, in particular for a motor vehicle, and motor vehicle - Google Patents

Abstract

The invention relates to an exhaust gas recirculation cooler (1), with at least two cooling cassettes (9b, 9c) arranged one on top of the other in a stacking direction (8), each of which has two interconnected half-shells (10a-d) and one through which the exhaust gas to be cooled can flow through the respective half-shells (10a-d) of the respective cooling cassette (9b, 9c) and arranged along the stacking direction (8) between the respective half-shells (10a-d) of the respective cooling cassette (9b, 9c), with one of the Half-shells (10a, 10b) of one of the cooling cassettes (9b) and one of the half-shells (10c, 10d) of the other cooling cassette (9c) are connected to one another in respective web areas (16, 17). An outer shell (21) at least partially surrounding the cooling cassettes (9b, 9c) is provided. Provided is a connecting to the web areas (16, 17), arranged along the stacking direction (8) between the one half-shell (10b) of one cooling cassette (9b) and the one half-shell (10c) of the other cooling cassette (9c) and of a Coolant for cooling the exhaust gas through which a cooling channel (20) can flow.

Description

The invention relates to an exhaust gas recirculation cooler and a motor vehicle with at least one such exhaust gas recirculation cooler.

The DE 10 2005 042 908 A1 there is known a fin structure having a fin plate accommodated in a heat transfer tube. Furthermore, from the EP 2 906 893 B1 a heat exchanger is known, which can be designed as an exhaust gas cooler.

The object of the present invention is to create an exhaust gas recirculation cooler and a motor vehicle with such an exhaust gas recirculation cooler, so that excessive, thermally induced stresses in the exhaust gas recirculation cooler can be avoided.

This object is achieved according to the invention by an exhaust gas recirculation cooler having the features of patent claim 1, by an exhaust gas recirculation cooler having the features of patent claim 7 and by a motor vehicle having the features of patent claim 10. Advantageous configurations of the invention are the subject matter of the dependent claims.

A first aspect of the invention relates to an exhaust gas recirculation cooler, in particular for a motor vehicle. The exhaust gas recirculation cooler can be used in or for an exhaust gas recirculation device, by means of which exhaust gas recirculation can be carried out. In the case of exhaust gas recirculation, at least part of an exhaust gas flowing through an exhaust tract, in particular an internal combustion engine, is branched off from the exhaust tract and returned to an intake tract, also known as the intake tract, in particular of the internal combustion engine, and introduced into the intake tract through which air can flow. The exhaust gas results from combustion processes that take place in at least one combustion chamber, in particular the internal combustion engine. In the respective combustion process, a fuel-air mixture, also simply referred to as a mixture, is burned, resulting in the exhaust gas. The mixture includes the air flowing through the intake tract, which is guided to and into the combustion chamber by means of the intake tract. In addition, the mixture includes a liquid fuel, for example. The air flowing through the intake tract takes the exhaust gas, which was recirculated and introduced into the intake tract, into the combustion chamber. In this case, the exhaust gas recirculation cooler is usually used to cool the exhaust gas to be recirculated on its way from the exhaust tract into the intake tract.

The exhaust gas recirculation cooler has at least two cooling cassettes which are arranged one on top of the other along a stacking direction and each have two half-shells which are connected to one another. The respective half-shells of the respective cooling cassette are designed separately from one another, with the cooling cassettes being designed separately from one another. In particular, the respective half-shell is made of sheet metal, and is therefore designed as a particularly one-piece sheet metal component. The feature that the respective half-shell is preferably designed in one piece means that the respective half-shell is not composed of several components that are designed separately from one another and are connected to one another, but rather the half-shell is designed as an integral body and thus manufactured in one piece, and is therefore designed as a monoblock. For example, one of the cooling cassettes is also referred to as the first cooling cassette and the other cooling cassette is also referred to as the second cooling cassette. For example, one of the half-shells of the first cooling cassette is called the first half-shell and the other half-shell of the first cooling cassette is called the second half-shell. For example, one of the half-shells of the second cooling cassette is also called the third half-shell and the other half-shell of the second cooling cassette is called the fourth half-shell.

The respective cooling cassette also has a respective gas duct, delimited by the respective half-shells of the respective cooling cassette and arranged along the stacking direction between the respective half-shells of the respective cooling cassette, through which the exhaust gas to be cooled by means of the exhaust gas recirculation cooler can flow. The second half-shell of the first cooling cassette and the third half-shell of the second cooling cassette are therefore arranged between the gas channels, for example viewed along the stacking direction. The second half-shell of the first cooling cassette and the third half-shell of the second cooling cassette face one another along the stacking direction and are connected to one another in the respective web areas. The web area of the second half-shell is also referred to as the first web area, and the web area of the third half-shell is also referred to as the second web area. In particular, the web areas are connected directly to one another. For example, the web areas are, in particular directly, cohesively connected to one another, in particular in such a way that the web areas are soldered to one another, in particular directly. The exhaust gas recirculation cooler also has an outer shell that at least partially, in particular at least predominantly and thus more than half or completely, surrounds the cooling cassettes. The respective gas channel can, for example, be flown through by the exhaust gas along a flow direction, so that the exhaust gas on its way flows through the gas channel in the flow direction through the respective gas channel and is thereby cooled, in particular such that the temperature of the exhaust gas viewed along the flow direction, ie in the flow direction, decreases. In this case, for example, the outer shell surrounds the cooling cassettes in the circumferential direction of the exhaust gas recirculation cooler running around the direction of flow, the circumferential direction running, for example, in a plane in which the stacking direction also runs.

The exhaust gas recirculation cooler also has at least one cooling duct, in particular in the flow direction of the exhaust gas, adjoining the web areas and arranged along the stacking direction between the second half-shell of the first cooling cassette and the third half-shell of the second cooling cassette, through which a preferably liquid coolant for cooling the exhaust gas can flow. In order to cool the exhaust gas, heat can be transferred from the exhaust gas to the second or third half-shell and from the second or third half-shell to the coolant flowing through the cooling channel. The cooling channel is delimited in a counterflow direction opposite to the direction of flow by the web areas connected to one another, and is therefore sealed. A liquid coolant is preferably used as the coolant, which coolant contains at least water, for example.

The cooling channel is partially and directly delimited in each case by the second half-shell of the first cooling cassette, by the third half-shell of the second cooling cassette and by a wall of the outer shell arranged laterally next to the cooling cassettes, wherein the wall, viewed in a connection direction running perpendicular to the flow direction and perpendicular to the stacking direction, adjoins the cooling cassettes and is therefore arranged laterally next to the cooling cassettes.

In order to be able to avoid excessive, thermally induced stresses in the exhaust gas recirculation cooler, in particular in the half-shells, which results in an advantageously long service life of the exhaust gas recirculation cooler, it is provided according to the invention that the outer shell, at least in a sub-area arranged laterally next to the web areas, viewed in particular in the connection direction, opposite ends of the respective web areas facing away from the cooling channel, which end in particular in the counterflow direction at the in particular free ends, in a direction pointing to the cooling channel and thus in particular parallel to the flow direction of the gas flowing through the respective gas channel Exhaust gas running direction is set back. Thus, the respective web area is arranged without overlapping to the outer shell at least over a respective length of the respective web area running along the flow direction, viewed in the connection direction. As a result, the web areas can expand or deform thermally, without excessive stresses occurring in the half-shells.

The outer shell is set back, for example, in relation to the ends of the web areas mentioned, in that the outer shell is provided with a cutout, also referred to as a recess, formed, for example, by a trimming of the outer shell. Thus, the web areas are, so to speak, free with regard to the outer shell, so that the web areas can deform, in particular expand, due to thermal factors, without excessive, in particular mechanical, stresses occurring in the half-shells.

Another embodiment is characterized in that the web area of the second half-shell of the first cooling cassette is adjoined by a first wall area of the second half-shell, which runs at an angle to the web area of the second half-shell and extends away from the third half-shell of the second cooling cassette, with the first wall area running in a first plane, for example, which runs obliquely or parallel to the stacking direction. The web area of the third half-shell is adjoined by a second wall area of the third half-shell, which runs at an angle to the web area of the third half-shell and extends away from the second half-shell, it being preferably provided that the second wall area extends in a second plane, which runs obliquely or parallel to the stacking direction. The web areas, the first wall area and the second wall area form a T-joint, ie a T-shaped structure designed as a solid body, as a result of which the exhaust gas cooler can be particularly robust.

It has proven to be particularly advantageous if the partial area is arranged next to the T-joint, particularly when viewed in the connection direction, so that the T-joint is arranged without overlapping with the outer shell when viewed in the connection direction. The partial area extends at least over the entire height of the T-joint running along the stacking direction, and therefore of the T-shaped structure. As a result, particularly strong, thermally induced expansions or deformations of the web areas can be permitted without excessive stresses occurring in the half-shells.

A further embodiment is characterized in that the first wall area and/or the second wall area is directly connected to the wall of the outer shell, in particular materially, in particular soldered, as a result of which a particularly high level of robustness can be achieved.

In order to avoid excessive stresses in the exhaust gas recirculation cooler, a further embodiment of the invention provides for the first wall area of the second half-shell to be connected directly to a corresponding wall area of the first half-shell, in particular materially, in particular soldered. Alternatively or additionally, the second wall area of the third half-shell is connected directly to a corresponding wall area of the fourth half-shell, in particular materially, in particular soldered, which means that the exhaust gas recirculation cooler can be particularly robust.

In order to be able to avoid excessive stresses in the exhaust gas recirculation cooler, it is provided in a further embodiment of the invention that the wall area of the first half-shell and/or the wall area of the fourth half-shell is directly connected to the wall of the outer shell, in particular with a material bond, in particular soldered.

The exhaust gas recirculation cooler can have a large number of half-shells, the previous and following statements on the respective half-shell being readily applicable to other half-shells and thus, for example, to an nth half-shell, with n designating an integer, positive, natural number.

A second aspect of the invention relates to an exhaust gas recirculation cooler, wherein the previous and following statements on the exhaust gas recirculation cooler according to the first aspect of the invention can also be easily applied to the exhaust gas recirculation cooler according to the second aspect of the invention and vice versa. The exhaust gas recirculation cooler according to the second aspect of the invention has at least two cooling cassettes which are arranged one on top of the other along a stacking direction and are therefore consecutive, each of which has two half-shells connected to one another and a gas duct through which exhaust gas to be cooled can flow, which is delimited by the respective half-shells of the respective cooling cassette and is arranged along the stacking direction between the respective half-shells of the respective cooling cassette.

One of the half-shells of one of the cooling cassettes has at least one lateral wall that at least partially overlaps the gas channel in a first direction running perpendicular to the stacking direction. For example, the exhaust gas flows on its way through the gas duct in a flow direction through the respective gas duct, with a temperature of the exhaust gas decreasing, for example, viewed in the flow direction, since the exhaust gas is cooled on its way through the gas duct. In this case, for example, the first direction mentioned runs perpendicularly to the direction of flow.

In the second aspect of the invention, said wall extends along the stacking direction and thus in a plane running parallel to the stacking direction towards at least one of the half-shells of the other cooling cassette. The wall ends along the stacking direction at an end edge of one half-shell of one cooling cassette. The wall has three longitudinal regions arranged in succession in a second direction perpendicular to the first direction and perpendicular to the stacking direction, namely a first longitudinal region, a second longitudinal region and a third longitudinal region arranged along the second direction between the first longitudinal region and the second longitudinal region. The third length area is designed as a transition area, over which the first length area, viewed in the second direction, transitions into the second length area in such a way that the wall tapers when viewed in the second direction.

In the second aspect of the invention, the exhaust gas recirculation cooler has an outer shell that at least partially surrounds the cooling cassettes. Furthermore, the exhaust gas recirculation cooler has a cooling duct through which the coolant can flow to cool the exhaust gas, which is arranged along the first direction between the second longitudinal region and a wall arranged laterally next to the cooling cassettes, in particular when viewed in the first direction, in particular in such a way that the cooling duct is in each case directly delimited by the second longitudinal region and the wall of the outer shell. The wall of one half-shell of one cooling cassette is also referred to as the first wall, with the wall of the outer shell also being referred to as the second wall. Due to the fact that the first wall of one half-shell of one cooling cassette tapers in the first direction, the second length region is set back from the second wall region of the outer shell compared to the first length region, i.e. in a direction opposite to the first direction and pointing away from the second wall of the outer shell, whereby the cooling channel is formed between the second wall of the outer shell and the second length region of one half-shell of one cooling cassette, in particular as a hollow space or intermediate space.

In order to avoid excessive stresses in the exhaust gas recirculation cooler, in particular in the half-shells, the second aspect of the invention provides that the transition area (third length area) at the end edge has an indentation which extends in particular from the half-shells of the other cooling cassette, as a result of which the transition area is set back in a third direction running parallel to the stacking direction and pointing away from the half-shells of the other cooling cassette. For example, the bulge is formed in a fourth length area of the end edge, so that, for example, the end edge in the fourth length area is set back in the fourth direction and compared to a fifth length area of the end edge, with the fifth length area directly adjoining the fourth length area, for example, in particular in a counterflow direction opposite to the direction of flow of the exhaust gas. Advantages and advantageous configurations of the first aspect of the invention are to be regarded as advantages and advantageous configurations of the second aspect of the invention and vice versa.

It has been found that at least one part of the transition area between the cooling cassettes can lead to an accumulation of material, in particular because the cooling cassettes are connected to one another, in particular directly, at least in the part of the transition area mentioned, in particular in a materially bonded manner and very particularly by soldering. In particular, it was found that a capillary effect can occur between the cooling cassettes, which can lead to a large accumulation of material. This accumulation of material can lead to high stresses in the half-shells due to thermally induced deformations or expansions, but this can now be avoided by the indentation. As a result of the indentation, the transition area is, so to speak, exposed, as a result of which both a capillary effect and an excessive accumulation of solder and thus material can be avoided.

In a particularly advantageous embodiment of the second aspect of the invention, the indentation is formed by a trimming of one half-shell of one cooling cassette, as a result of which excessive mechanical stresses can be avoided particularly well.

A further embodiment is characterized in that the first longitudinal area, the second longitudinal area and the third longitudinal area are formed in one piece with one another. In other words, the first longitudinal area, the second longitudinal area and the third longitudinal area are an integral part of a body which is produced integrally and is therefore made in one piece and is therefore designed as a monoblock, so that the first longitudinal area, the second longitudinal area and the third longitudinal area are not composed of components that are formed separately from one another and are connected to one another, but rather the first longitudinal area, the second longitudinal area and the third longitudinal area are formed by bodies that are integral and therefore in one piece and therefore designed as a monoblock. As a result, excessive loads on the exhaust gas recirculation cooler can be avoided particularly well.

A third aspect of the invention relates to a motor vehicle, preferably designed as a motor vehicle, in particular as a passenger car, which has at least one exhaust gas recirculation cooler according to the first aspect of the invention and/or at least one exhaust gas cooler according to the second aspect of the invention.

• 1 eine schematische Perspektivansicht eines Abgasrückführkühlers für ein Kraftfahrzeug;
• 2 ausschnittsweise eine schematische und geschnittene Perspektivansicht des Abgasrückführkühlers;
• 3 ausschnittsweise eine weitere schematische und geschnittene Perspektivansicht des Abgasrückführkühlers;
• 4 ausschnittsweise eine weitere schematische und geschnittene Perspektivansicht des Abgasrückführkühlers;
• 5 ausschnittsweise eine weitere schematische und geschnittene Perspektivansicht des Abgasrückführkühlers;
• 6 ausschnittsweise eine weitere schematische und geschnittene Perspektivansicht des Abgasrückführkühlers;
• 7 ausschnittsweise eine weitere schematische und geschnittene Perspektivansicht des Abgasrückführkühlers; und
• 8 ausschnittsweise eine schematische Perspektivansicht von Kühlkassetten des Abgasrückführkühlers.

Further details of the invention result from the following description of a preferred exemplary embodiment with the accompanying drawings. It shows:

• 1 a schematic perspective view of an exhaust gas recirculation cooler for a motor vehicle;
• 2 a detail of a schematic and sectional perspective view of the exhaust gas recirculation cooler;
• 3 a further schematic and sectioned perspective view of the exhaust gas recirculation cooler;
• 4 a further schematic and sectioned perspective view of the exhaust gas recirculation cooler;
• 5 a further schematic and sectioned perspective view of the exhaust gas recirculation cooler;
• 6 a further schematic and sectioned perspective view of the exhaust gas recirculation cooler;
• 7 a further schematic and sectioned perspective view of the exhaust gas recirculation cooler; and
• 8th A partial schematic perspective view of cooling cassettes of the exhaust gas recirculation cooler.

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

1 shows a schematic perspective view of an exhaust gas recirculation cooler 1 for a motor vehicle, in particular for a motor vehicle. This means that the motor vehicle has the exhaust gas recirculation cooler 1 in its fully manufactured state. In its fully manufactured state, the motor vehicle also has an internal combustion engine, by means of which the motor vehicle can be driven. The internal combustion engine has an intake tract through which air can flow and at least one combustion chamber into which the air flowing through the intake tract is guided by means of the intake tract. In addition, a particularly liquid fuel is introduced into the combustion chamber, as a result of which a fuel-air mixture comprising the air and the fuel, also referred to simply as a mixture, is formed. The mixture is burned in the combustion chamber, resulting in exhaust gas from the internal combustion engine. The internal combustion engine has an exhaust gas tract through which the exhaust gas can flow and into which the exhaust gas from the combustion chamber flows. The exhaust tract is in 1 partially shown and denoted by 2. In particular, the exhaust tract 2 includes a manifold 3, also referred to as an exhaust manifold. The intake tract is in 1 also partially recognizable and labeled 4. The intake tract 4 includes, for example, an air pipe 5 . The internal combustion engine also has an exhaust gas recirculation device 6 which includes the exhaust gas recirculation cooler 1 . The exhaust gas recirculation device 6 has a recirculation line 7 , by means of which at least part of the exhaust gas flowing through the exhaust gas tract 2 is branched off from the exhaust gas tract 2 , returned to the intake tract 4 and introduced into the intake tract 4 . The exhaust gas recirculation cooler 1 , which is also referred to as an EGR cooler, is arranged in the recirculation line 7 . The exhaust gas branched off from the exhaust tract 2 flows through the return line 7 and is returned to the intake tract 4 by means of the return line 7 . On its way through the recirculation line 7, the exhaust gas flows through the exhaust gas recirculation cooler 1, by means of which the exhaust gas to be recirculated is cooled.

For example, the internal combustion engine has at least one exhaust gas turbocharger, which has a turbine that is arranged in the exhaust tract 2 and can be driven by the exhaust gas, and a compressor that is arranged in the intake tract 4 and can be driven by the turbine. Air flowing through this intake tract 4 can be compressed by means of the compressor. For example, exhaust gas recirculation device 6 is designed as a high-pressure exhaust gas recirculation device, by means of which exhaust gas recirculation (EGR) designed as high-pressure exhaust gas recirculation (HP-EGR) can be carried out. For this purpose, at least part of the exhaust gas from the exhaust gas tract 2 can be branched off at a discharge point by means of the recirculation line 7, which is arranged upstream of the turbine in the direction of flow of the exhaust gas flowing through the exhaust gas tract 2. For example, the exhaust gas flowing through the recirculation line 7 can be introduced at a feed point into the intake tract 4 by means of the recirculation line 7, the feed point preferably being arranged upstream of the compressor in the flow direction of the air flowing through the intake tract 4.

The exhaust gas recirculation device 6 also includes, for example, an exhaust gas recirculation valve (EGR valve) which is arranged in particular in the recirculation line 7 and by means of which a quantity of the exhaust gas to be recirculated can be adjusted.

The exhaust gas recirculation cooler 1 is in 2 until 8th shown in a respective, schematic and sectional perspective view in part. Particularly good looking 2 until 4 It can be seen that the exhaust gas recirculation cooler 1 has a plurality of cooling cassettes 9a-d arranged one after the other along a stacking direction illustrated by a double arrow 8. The cooling cassettes 9a-d are formed separately from one another and are connected to one another, in particular cohesively, in particular soldered to one another. In particular, the cooling cassettes 9a-d are directly, in particular cohesively, connected to one another, in particular directly soldered to one another. The exhaust gas recirculation cooler 1 is described below with reference to the cooling cassettes 9b and 9c. Out of 4 it can be seen that the exhaust gas recirculation cooler 1 can have a further cooling cassette 9e, the cooling cassettes 9a-e being arranged one on top of the other along the stacking direction illustrated by the double arrow 8. The cooling cassette 9b is one of the cooling cassettes 9a-e and is also called the first cooling cassette, and the cooling cassette 9c is another one of the cooling cassettes 9a-e and is also called the second cooling cassette. The respective cooling cassette 9b, c has in each case, in particular exactly, two, in particular directly, connected to one another, in particular bonded and in particular soldered, half-shells 10a-d. The half-shell 10a is one of the half-shells 10a and 10b of the cooling cassette 9b and is also referred to as the first half-shell, and the half-shell 10b, the other half-shell of the cooling cassette 9b, is also referred to as the second half-shell. The half-shell 10c is one of the half-shells 10d of the cooling cassette 19 and is also called the third half-shell, and the half-shell 10d is the other half-shell of the cooling cassette 19 and is also called the fourth half-shell. The previous and following explanations for the cooling cassettes 9b and 9c can also be easily transferred to the other cooling cassettes 9a, 9d and 9e and vice versa. Based on the cooling cartridges 9b and 9c it can be seen that the respective cooling cartridge 9b, c in each case at least or exactly one of the to be returned and gas channel 11, 12 through which the exhaust gas to be cooled can flow in a direction of flow, the direction of flow being illustrated by an arrow 13. The exhaust gas thus flows on its way through the return line 7 and thus through the gas channels 11 and 12 in the direction of flow illustrated by the arrow 13 through the gas channels 11 and 12 . The respective gas channel 11, 12 is delimited, in particular directly, by the respective half-shells 10a, b or 10c, d of the respective cooling cassette 9b, c and is arranged along the stacking direction (double arrow 8) between the respective half-shells 10a, b or 10c, d of the respective cooling cassette 9b, c.

Particularly good looking 2 it can be seen that, for example, within the respective gas duct 11, 12 a respective lamella pack 14, 15 formed from sheet metal, for example, is arranged, around which the exhaust gas flows on its way through the respective gas duct 11, 12. The respective disk set 14, 15 has, for example, respective disks which run at least essentially in a meandering manner, in particular in a plane of extent which runs, for example, perpendicularly to the direction of flow. In this case, for example, the stacking direction runs in the extension plane. The respective disk set 14, 15 has a particularly large surface area, via which heat from the exhaust gas flowing through the respective gas duct 11, 12 can transfer to the respective disk set 14, 15 in a particularly advantageous manner. The heat can advantageously be transferred from the respective disk pack 14, 15 to the respective half-shells 10a and 10b or 10c and 10d, as a result of which the exhaust gas can advantageously be cooled.

Particularly good looking 2 and 3 It can be seen that the second half-shell 10b and the third half-shell 10c are connected to one another, in particular directly, in the respective web areas 16 and 17, in particular in such a way that the web areas 16 and 17 of the half-shells 10b and 10c are connected to one another, in particular directly. For example, the web areas 16 and 17 are, in particular directly, cohesively connected to one another, in particular soldered to one another. The land area 16 is the land area of the half-shell 10b, and the land area 17 is the land area of the half-shell 10c. It can be seen that the web area 16 of the half-shell 10b of the cooling cassette 9b and the web area 17 of the half-shell 10c of the cooling cassette 9c form a web 18 which, in particular in the direction of flow of the exhaust gas illustrated by the arrow 13, is in particular directly exposed to the exhaust gas and flows around it, and is therefore directly exposed to the exhaust gas.

The cooling cassettes 9b and 9c form a cooling cassette pair 19, which is explained in more detail below. Particularly good looking 4 It can be seen that the exhaust gas recirculation cooler 1 also has an outer shell 21 made in particular from a metallic material, in particular sheet metal, which surrounds the cooling cassettes 9a-e, preferably completely, in particular in the circumferential direction of the cooling cassettes 9a-e running around the direction of flow. Particularly good looking 3 It can be seen that the exhaust gas recirculation cooler 1 also has at least or exactly one cooling channel 20, in particular for each cooling cassette pair 19, which is in particular in the flow direction adjoining the web areas 16 and 17 and thus to the web 18 and through which a preferably liquid coolant can flow, in particular during operation of the exhaust gas recirculation device 6. The heat can be transferred from the disk packs 14 and 15 to the half-shells 10b and 10c, for example, and the heat can be transferred from the half-shells 10b and 10c to the coolant which flows through the cooling channel 20 between the half-shells 10b and 10c. It can be seen that the cooling channel 20 is arranged along the stacking direction (double arrow 8) between the half-shells 10b and 10c and, in the exemplary embodiment shown in the figures, is limited on the one hand directly by the half-shell 10b and on the other hand directly by the half-shell 10c, namely along the stacking direction (double arrow 8).

Out of 4 it can be seen that the outer shell 21 has a wall 22 arranged laterally next to the cooling cassettes 9a-e. In particular, the wall 22 is arranged next to the cooling cassettes 9b and 9c in a connection direction which runs perpendicularly to the stacking direction and perpendicularly to the flow direction and is illustrated by an arrow 23 . The cooling channel 20 is also partially and directly delimited by the wall 22 , specifically in the connection direction illustrated by the arrow 23 , which points away from the respective cooling cassette 9 b , c and points towards the wall 22 .

In order to avoid excessive stresses, particularly in the half-shells 10b and 10c, the outer shell 21 is particularly good 4 can be seen, in a partial area TB arranged laterally next to the web areas 16 and 17 viewed in the connection direction and thus laterally next to the web 18 viewed in the connection direction opposite ends E of the web areas 16 and 17 facing away from the cooling channel 20 in a direction pointing to the cooling channel 20, coinciding with the direction of flow and thus illustrated by the arrow 13. For this purpose, the wall 22 has a recess 24, also referred to as a recess, through which the web areas 16 and 17 are at least partially overlapped in the connection direction illustrated by the arrow. Thus, the web areas 16 and 17, and consequently the web 18 viewed in the connection direction, are arranged at least partially without overlapping with the wall 22 of the outer shell 21.

Since the land portions 16 and 17 are directly exposed to the hot exhaust gas, which exhaust gas may have a high temperature of, for example, 600° C. or more, the land portions 16 and 17 are extremely heated. Thus, the half-shells 10b and 10c have a very high temperature in their web areas 16 and 17. However, in the further areas adjoining the web areas 16 and 17 in the direction of flow, the half-shells 10b and 10c have a significantly lower temperature compared to the web areas 16 and 17, since, for example, the further areas delimit the cooling channel 20, in particular directly. As a result, thermally induced deformations or expansions of the web areas 16 and 17 can occur. Since the wall 22 now has the recess 24 and is therefore set back towards the cooling channel 20 compared to the ends E, so that the web areas 16 and 17 are arranged without overlapping with the wall 22 at least over a length running in the direction of flow, viewed in the connection direction, the thermally induced deformations and expansions of the web areas 16 and 17 can advantageously be permitted without excessive mechanical stresses in the half shells 10b and 10c coming. As a result, for example, the tendency of the exhaust gas recirculation cooler 1 to crack can be kept particularly low.

Particularly good looking 4 it can be seen that the web area 16 of the half-shell 10b is adjoined by a first wall area W1 of the half-shell 10b running at an angle to the web area 16 of the half-shell 10b and extending, for example, in a plane running parallel to the stacking direction and extending away from the half-shell 10c. The web area 17 of the half-shell 10c is adjoined by a second wall area W2 of the half-shell 10c running at an angle, in particular perpendicularly, to the web area 17 of the half-shell 10c and extending, for example, in a plane running parallel to the stacking direction and extending away from the half-shell 10b. The web areas 16 and 17 and the wall areas W1 and W2 form a T-joint 25, which is an at least essentially T-shaped structure of the exhaust gas recirculation cooler 1, in particular of the cooling cassette pair 19, designed as a solid body and formed by the web areas 16 and 17 and the wall areas W1 and W2. The wall area W1 is in particular directly connected to the half-shell 10a, in particular cohesively, in particular soldered, and the wall area W2 is, in particular directly, connected to the half-shell 10d, in particular cohesively, in particular soldered. The half-shell 10a is connected, in particular directly and/or cohesively, to the wall 22, in particular soldered, and the half-shell 10d is connected, in particular directly and/or cohesively, to the wall 22, in particular soldered. As a result, the cooling channel 20 is also sealed between the wall 22 and the cooling cassettes 9a-e or 9b and 9c.

The exhaust gas recirculation cooler 1 also has a component 26 common to the cooling cassettes 9a-e, produced by casting and thus designed as a cast component, which is also referred to as a diffuser. The exhaust gas can flow through the component 26 , the exhaust gas being supplied to the gas channels 11 and 12 via the component 26 , and consequently being divided between the gas channels 11 and 12 . It can be seen that the outer shell 21, the cooling cassettes 9a-e and in particular the web areas 16 and 17 are each at least partially arranged in the component 26, so that the component 26, in particular in the circumferential direction of the cooling cassettes 9a-e, surrounds at least respective partial or longitudinal areas of the outer shell 21 of the web areas 16 and 17, in particular completely circumferentially. In particular, the component 26 is connected directly to the outer shell 21, in particular the wall 22. The at least partial arrangement of the outer shell 21, in particular the wall 22 and the web 18 in the component 26 can be particularly good 5 be recognized. Also from 5 the recess 24 of the wall 22 can be seen particularly well.

The recess 24 is also particularly good 6 recognizable. In particular, is particularly good looking 6 recognizable that through the recess 24 the wall 22 is set back towards the cooling channel 20 in relation to the front ends E of the webs 16 and 17 . The T-Shock 25 is particularly good looking 7 recognizable. Also visible is the recess 24, through which the T-joint 25 is at least partially overlapped in the connection direction (arrow 23).

Out of 4 it can be seen that the wall area W1 of the half-shell 10b is connected, in particular soldered, directly and/or cohesively to a third wall area W3 of the half-shell 10a. The wall area W3 of the half-shell 10a is formed by a wall 27 of the half-shell 10a, the wall 27 and thus the wall area W3 also consisting of 8th are recognizable. In particular, is off 8th an outside A of the wall 27 recognizable, the outside A of the wall 22 facing in particular in the connection direction illustrated by the arrow 23 . The wall 27 is also referred to as the first wall of the half-shell 10a, the wall 27 at least partially overlapping the gas channel 11 of the cooling cassette 9b in the connection direction (arrow 23), also referred to as the first direction. The wall region W1 is arranged at least partially between the gas channel 11 of the cooling cassette 9b and the wall 27 along the connection direction, which is also designated as the first direction and illustrated by the arrow 23 4 it can be seen that the gas channel 11 is delimited in the connection direction illustrated by the arrow 23 in part directly by the wall region W3 and thus by the wall 27 (first wall) of the half-shell 10a. It is particularly conceivable here for the wall 27 to be connected, in particular by soldering, to the wall 22, in particular in a materially bonded manner and/or directly. The wall 27 extends along the stacking direction and in particular in a plane running parallel to the stacking direction towards the half-shell 10c of the cooling cassette 9c, the wall 27 in particular running at least substantially parallel to the wall region W1. In particular, the wall 27 runs at an angle, i.e. obliquely or perpendicularly, to a web area of the half-shell 10a, whose web area forms a further web with a web area of a corresponding half-shell of the cooling cassette 9a, to which the previous and following statements on the web 18 can be transferred and vice versa.

Out of 8th it can be seen that the wall 27 ends at an end edge EK of the half-shell 10a of the cooling cassette 9b along the stacking direction and viewed towards the half-shell 10c. In addition, viewed along the direction of flow, the wall 27 has three longitudinal regions arranged in succession in the direction of flow perpendicular to the first direction and perpendicular to the stacking direction and also referred to as the second direction, namely a first longitudinal region L1, a second longitudinal region L2 and a third longitudinal region L3. In other words, the direction of flow illustrated by the arrow 13 is a second direction, which runs perpendicularly to the first direction, and therefore perpendicularly to the connection direction and also perpendicularly to the stacking direction. Viewed along the direction of flow (second direction), the longitudinal area L3 is arranged between the longitudinal areas L1 and L2, with the wall 27 viewed in the second direction (direction of flow) extending in such a way that the longitudinal area L1 in the direction of flow merges via the longitudinal area L3 into the longitudinal area L2. The length area L3 is thus a transition area of the wall 27. The length area L1 merges into the length area L2 via the transition area in such a way that the wall 27 tapers in the second direction (flow direction, arrow 13). As a result, the outer side A of the length region L2 is set back in a direction opposite to the connection direction and pointing away from the wall 22 compared to the outer side of the length region L1, and therefore set back away from the wall 22. As a result, a cavity or intermediate space in the form of the cooling channel 20 is formed along the first direction between the length region L2 and the wall 22 of the outer shell 21, which is delimited directly by the length region L2 in the reset direction and directly by the wall 22 of the outer shell 21 in the connection direction (first direction) opposite the reset direction and is therefore arranged between the length region L2 and the wall 22 along the first direction or along the reset direction. The cooling channel 20 is thus arranged partly along the stacking direction between the half-shells 10b and 10c and partly along the connection direction between the length region L2 and the wall 22 .

In order to avoid excessive stresses, particularly in the half-shell 10a, the longitudinal area L3 (transitional area) has an indentation 28 at the end edge EK, as a result of which the longitudinal area L3 runs parallel to the stacking direction and points away from the half-shells 10c and 10d of the cooling cassette 9c, in 8th illustrated by an arrow 29, third direction is set back. It can be seen that the indentation 28 is arranged in the area of a so-called case corner 30 of the half-shell 10b of the cooling cassette 9b. The indentation 28 makes it possible to avoid excessive accumulations of a solder in the area of the case corner 30, by means of which the cooling cassettes 9c and 9b are connected to one another, in particular directly, so that in the area of the case corner 30 excessive material accumulations and, as a result, excessive, thermally induced mechanical stresses can be avoided.

Reference List

1

exhaust gas recirculation cooler

2

exhaust tract

3

exhaust manifold

4

admission tract

5

air pipe

6

exhaust gas recirculation device

7

return line

8th

double arrow

9a-d

cooling cassette

10a-d

half shell

11

gas channel

12

gas channel

13

Arrow

14

plate pack

15

slat package

16

bridge area

17

bridge area

18

web

19

cooling cassette pair

20

cooling channel

21

outer shell

22

wall

23

Arrow

24

recess

25

T-joint

26

component

27

wall

28

indentation

29

Arrow

30

suitcase corner

A

outside

E

End

EK

trailing edge

L1

first length range

L2

second length range

L3

third length range

w1

wall area

W2

wall area

QUOTES INCLUDED IN DESCRIPTION

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

Patent Literature Cited

• DE 102005042908 A1 [0002]
• EP 2906893 B1 [0002]

Claims (10)

Exhaust gas recirculation cooler (1), with: - At least two cooling cassettes (9b, 9c) arranged one on top of the other along a stacking direction (8), which each have two interconnected half-shells (10a-d) and a gas channel (11, 12) through which exhaust gas to be cooled can flow, which is delimited by the respective half-shells (10a-d) of the respective cooling cassette (9b, 9c) and is arranged along the stacking direction (8) between the respective half-shells (10a-d) of the respective cooling cassette (9b, 9c). , wherein one of the half-shells (10a, 10b) of one of the cooling cassettes (9b) and one of the half-shells (10c, 10d) of the other cooling cassette (9c) are connected to one another in respective web areas (16, 17), - an outer shell (21) at least partially surrounding the cooling cassettes (9b, 9c), - a cooling duct (20) adjoining the web areas (16, 17), arranged along the stacking direction (8) between the one half-shell (10b) of one cooling cassette (9b) and the one half-shell (10c) of the other cooling cassette (9c) and through which a coolant can flow for cooling the exhaust gas, which in each case passes partially and directly through the one half-shell (10b) of one cooling cassette (9b), through the one half-shell (10c) of the other cooling cassette (9c ) and is delimited by a wall (22) of the outer shell (21) arranged laterally next to the cooling cassettes (9b, 9c), the outer shell (21) being set back in a direction (13) pointing towards the cooling duct (20), at least in a partial area (TB) arranged laterally next to the ridge regions (16, 17) opposite ends (E) of the ridge regions (16, 17) facing away from the cooling duct (20). Exhaust gas recirculation cooler (1) after claim 1 , dadurch gekennzeichnet , dass: - sich an den Stegbereich (16) der einen Halbschale (10b) der einen Kühlkassette (9b) ein winklig zu dem Stegbereich (16) der einen Halbschale (10b) der einen Kühlkassette (10b) verlaufender und sich von der einen Halbschale (10c) der anderen Kühlkassette (9c) wegerstreckender, erster Wandungsbereich (W1) der einen Halbschale (10b) der einen Kühlkassette (10b) anschließt, und - sich an den Stegbereich (17) der einen Halbschale (10c) der anderen Kühlkassette (9c) ein winklig zu dem Stegbereich (17) der einen Halbschale (10c) der anderen Kühlkassette (9c) verlaufender und sich von der einen Halbschale (9c) der einen Kühlkassette (9c) wegerstreckender, zweiter Wandungsbereich (W2) der einen Halbschale (10c) der anderen Kühlkassette (9c) anschließt, wobei die Stegbereiche (16, 17), der erste Wandungsbereich (W1) und der zweite Wandungsbereich (W2) einen T-Stoß (25) bilden. Exhaust gas recirculation cooler (1) after claim 2 , characterized in that the partial area (TB) is arranged laterally next to the T-joint (25) and extends at least over the entire height of the T-joint (25) running along the stacking direction (8). Exhaust gas recirculation cooler (1) after claim 2 or 3 , characterized in that the first wall area (W1) and/or the second wall area (W2) is connected directly to the wall (22) of the outer shell (21). Exhaust gas recirculation cooler (1) according to one of claims 2 until 4 , characterized in that : - the first wall area (W1) of one half-shell (10b) of one cooling cassette (9b) is connected directly to a corresponding wall area of the other half-shell (10a) of one cooling cassette (9b), and/or - the second wall area (W2) of one half-shell (10c) of the other cooling cassette (9c) is directly connected to a corresponding wall area of the other half-shell (10d) of the other cooling cassette (9c). is. Exhaust gas recirculation cooler (1) after claim 5 , characterized in that the wall area of the other half-shell (10a) of one cooling cassette (9b) and/or the wall area of the other half-shell (10d) of the other cooling cassette (9c) is connected directly to the wall (22) of the outer shell (21). Exhaust gas recirculation cooler (1), with: - at least two cooling cassettes (9b, 9c) arranged one on top of the other along a stacking direction (8), which each have two interconnected half-shells (10a-d) and a gas duct (11 , 12), wherein one of the half-shells (10a-d) of one of the cooling cassettes (9b, 9c) has at least one lateral first wall (27) that at least partially overlaps the gas channel (11, 12) in a first direction (23) running perpendicularly to the stacking direction (8), which: ◯ extends along the stacking direction (8) towards at least one of the half-shells (10c, 10d) of the other cooling cassette (9c), ◯ along the stacking direction (8) at an end edge (EK) of one half-shell (10a) of the one cooling cassette (9b), and ◯ has three longitudinal regions (L1, L2, L3) arranged in succession in a second direction (13) perpendicular to the first direction (23) and perpendicular to the stacking direction (8), namely one first longitudinal area (L1), a second longitudinal area (L2) and a third longitudinal area (L3) arranged along the second direction (13) between the first longitudinal area (L1) and the second longitudinal area (L2), which is designed as a transition area via which the first longitudinal area (L1) merges into the second longitudinal area (L2) in such a way that the first wall (27) narrows when viewed in the second direction (13), - one of the cooling cassettes (9b, 9c) at least partially surrounding outer shell (21), - a cooling channel (20) through which a coolant for cooling the exhaust gas can flow, which is arranged along the first direction (23) between the second length region (L2) and a second wall (22) of the outer shell (21) arranged laterally next to the cooling cassettes (9b, 9c), the transition region (L3) having an indentation (28) at the end edge (EK), whereby the transition region (L3) moves in a direction parallel to the stacking direction (8) running and from the half-shells (10c, 10d) of the other cooling cassette (9c) pointing away, third direction (29) is set back. Exhaust gas recirculation cooler (1) after claim 7 , characterized in that the indentation (28) is formed by a cut of a half-shell (10a) of a cooling cassette (9b). Exhaust gas recirculation cooler (1) after claim 7 or 8th , characterized in that the longitudinal areas (L1, L2, L3) are formed in one piece with each other. Motor vehicle with at least one exhaust gas recirculation cooler (1) according to one of the preceding claims.

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