EP2402585A1 - Device for reclaiming exhaust gas for a combustion engine - Google Patents

Abstract

The device has an exhaust gas pipe (3) conducting exhaust gas. A channel (1) conducts air to a combustion engine, where the gas pipe extends into the channel. The gas pipe is in thermal exchange with a coolant from a coolant circuit in an area of insertion in the channel. The gas pipe is connectable to an assembly member (2), where the coolant passes through a coolant channel (6) that is provided at the assembly member. The gas pipe includes a flange (4) that is connectable to the assembly member, where a seal (5) is arranged between the flange and the assembly member. The assembly member is formed of metal.

Description

The invention relates to a device for exhaust gas recirculation for an internal combustion engine according to the preamble of claim 1 and claim 12

The recirculation of exhaust gas of an internal combustion engine, for example, to reduce pollutants is common in commercial vehicles and passenger cars. In the course of increasing demands on the pollutant poverty increasing return rates are required, for example, to over 30%. Irrespective of measures such as exhaust gas cooling, the recirculated exhaust gas can have very high temperatures, depending on the recirculation rate and the operating state. It is known and customary to provide the inflow of the recirculated exhaust gas into the combustion air in a metal plenum region (intake manifold).

It is the object of the invention to provide a device for exhaust gas recirculation for an internal combustion engine, by means of which a large stream of hot exhaust gas can be introduced into the combustion air in a simple manner.

This object is achieved for an aforementioned device according to the invention with the characterizing features of claim 1. The thermal exchange with a coolant prevents the area of the exhaust gas outlet from overheating into the air-conducting duct. As a result, the surrounding components can be designed according to uncritical and higher security for cases of extreme operating conditions and malfunction z. B. exhaust gas cooler or exhaust gas control is achieved. In the context of the invention, a coolant means any suitable fluid circuit of the internal combustion engine or of a motor vehicle as a whole, such as the engine coolant circuit, a separate low-temperature cooling circuit or the refrigeration circuit of an air conditioning system. The coolant is preferably liquid, but in individual cases may also be gaseous or present in several phases.

In a preferred embodiment of the invention, the exhaust pipe is connected to a mounting member, in particular made of metal, wherein the coolant flows through a coolant channel provided on the mounting member. As a result, the mounting member can be cooled, so that it is possible to provide the mounting member on non-temperature-resistant structures. Examples include an air-conducting duct made of plastic or an intercooler made of aluminum. Examples of a mounting member according to the invention are a plate, a sheet metal part, milled part or other suitable component, preferably made of aluminum or steel, which is designed for receiving the exhaust pipe on the one hand and for fixing to the air duct on the other. The particular type of determination is arbitrary depending on the requirements, so for example cohesively (soldered, welded, glued, etc.), with fasteners such as screws, rivets, clips, etc. or otherwise.

For ease of determination while the exhaust pipe in a preferred detail design has a connectable to the mounting member flange. As a result, in particular a detachable fixing, for example by screwing the flange, possible. In this case, it may be provided in a further preferred detail design that the coolant channel also flows around the screws or fixing means, since these represent thermal bridges. Further preferred may be between the Flange and the mounting member to be arranged a seal. As a result, not only is there a seal between the exhaust pipe and the outer space, but also an additional insulation against heat transfer from the hot exhaust pipe to the mounting member. Generally advantageous, the coolant channel is arranged on a side opposite the flange of the mounting member, but can also be provided depending on the requirements on the same page.

In an expedient embodiment of the invention, the coolant channel is designed as a pipe, in particular cohesively connected to the mounting member. Such a pipeline may have a polygonal or round cross-section. The connection of the coolant channel to a cooling circuit can then be done, for example, by simply attaching hoses on free ends of the pipeline.

In an alternative or supplementary embodiment, the coolant channel can also be formed as a one-piece or multi-piece sheet-metal part, in particular materially connected to the mounting member.

In a preferred embodiment of the invention, the region of the mouth of the exhaust pipe is provided on a through-flow of the coolant charge air cooler. Here, the exhaust gas in the radiator area can flow into the charge air, so that a good turbulence and at the same time a further cooling of the exhaust gas or better use of the intercooler is given. In an advantageous development, the area of the confluence can be arranged on a coolant-side collector member of the intercooler to simplify the construction. With a suitable design of the collector member so can already sufficient cooling of the area the confluence can be achieved by the coolant flows in the collector. Depending on the requirements but can also be provided an additional coolant line for cooling the exhaust pipe.

In an alternative embodiment, the exhaust pipe opens into the channel upstream of an intercooler. Especially in this area conventional air ducts are often made of plastic to save costs and weight, which previously opposed inflow of hot exhaust gas. In general, it is also advantageous that when inflow above the intercooler optimum mixing and further cooling of the exhaust gas charge air mixture takes place in the intercooler.

In general, it is preferably provided for cost and weight savings and made possible by the invention that the channel is formed at least in the region of the mouth of the exhaust pipe of a plastic.

Further advantageously, the invention also includes the features of any one of claims 12 to 16, thereby further avoiding excessive local heating of components by the exhaust stream.

The object of the invention is also achieved by the characterizing features of claim 12 for an aforementioned device. By forming the exhaust pipe in a region of its mouth into the channel as at least one pipe section having a plurality of exhaust ports for the exhaust gas along the pipe section, a split of the exhaust gas stream into a plurality of partial streams over a large spatial area is achieved. As a result, excessive local heating, for example, a wall of the channel, avoided and also improves the mixing of exhaust gas and air.

In one possible embodiment, the exhaust pipe branches in the region of its confluence into a plurality of pipe sections, whereby a particularly uniform distribution of the exhaust gas is achieved. In the interest of a simple design, however, only a single pipe section can be provided for the inflow of the exhaust gas into the air.

In a particularly preferred detailed embodiment of the invention, the outflow openings are distributed according to number and / or size over a length of the pipe section, that a hydraulic Ausströmquerschnitt per unit length of the pipe section increases in the flow direction of the exhaust gas. As a result, an occurring pressure drop over the length of the pipe section is taken into account, so that the outflowing exhaust gas mass flow can be distributed as required and in particular uniformly over the length of the pipe section.

As a supplemental or alternative advantageous measure flow obstacles are arranged on at least some of the outflow openings, whereby a swirling achieved and / or a preferred outflow direction can be specified. In this way, a harmful heat input, for example, in the walls of the channel can be additionally avoided.

To optimize the distribution of the exhaust gas in the air flow flowing through the channel and thus to equalize the temperature or avoid temperature peaks, it may be provided that the outflow openings at least predominantly in an outflow angle of between 45 ° and 135 °, in particular between 90 ° and 135 °, are aligned with a main flow direction of the air in the channel.

Further advantages and features of a device according to the invention will become apparent from the embodiments described below and from the dependent claims.

Fig. 1

zeigt eine Schnittansicht durch ein erstes Ausführungsbeispiel der Erfindung.

Fig. 2

zeigt eine Draufsicht auf ein Montageglied des Beispiels aus Fig.1.

Fig. 3

zeigt eine seitliche und stirnseitige Draufsicht auf eine Abgasleitung des Beispiels aus Fig. 1.

Fig. 4

zeigt eine Schnittansicht eines zweiten Ausführungsbeispiels der Erfindung.

Fig. 5

zeigt eine Schnittansicht eines dritten Ausführungsbeispiels der Erfindung.

Fig. 6

zeigt eine Draufsicht auf das Beispiel aus Fig. 5.

Fig. 7

zeigt eine Schnittansicht eines vierten Ausführungsbeispiels der Erfindung.

Fig. 7a

zeigt eine Abwandlung des vierten Ausführungsbeispiels.

Fig. 8

zeigt eine Draufsicht auf ein fünftes Ausführungsbeispiel der Erfindung.

Fig. 9

zeigt eine Draufsicht auf ein sechstes Ausführungsbeispiel der Erfindung von oben.

Fig. 10

zeigt das Beispiel aus Fig. 9 mit eingesetzter Abgasleitung.

Fig. 11

zeigt eine Schnittansicht durch ein siebentes Ausführungsbeispiel der Erfindung.

Fig. 12

zeigt eine Schnittansicht durch ein achtes Ausführungsbeispiel der Erfindung.

Fig. 13

zeigt eine Schnittansicht durch ein neuntes Ausführungsbeispiel der Erfindung.

Fig. 14

zeigt eine Schnittansicht durch ein zehntes Ausführungsbeispiel der Erfindung.

Fig. 15

zeigt vier Schnittansichten und teilweise Draufsichten in mehreren Ebenen des Ausführungsbeispiels aus Fig. 14.

Fig. 16

zeigt verschiedene Ausströmwinkel eines elften Ausführungsbeispiels der Erfindung.

Hereinafter, several preferred embodiments of the invention will be described and explained in more detail with reference to the accompanying drawings.

Fig. 1

shows a sectional view through a first embodiment of the invention.

Fig. 2

shows a plan view of a mounting member of the example Fig.1 ,

Fig. 3

shows a side and frontal plan view of an exhaust pipe of the example Fig. 1 ,

Fig. 4

shows a sectional view of a second embodiment of the invention.

Fig. 5

shows a sectional view of a third embodiment of the invention.

Fig. 6

shows a plan view of the example Fig. 5 ,

Fig. 7

shows a sectional view of a fourth embodiment of the invention.

Fig. 7a

shows a modification of the fourth embodiment.

Fig. 8

shows a plan view of a fifth embodiment of the invention.

Fig. 9

shows a plan view of a sixth embodiment of the invention from above.

Fig. 10

shows the example Fig. 9 with inserted exhaust pipe.

Fig. 11

shows a sectional view through a seventh embodiment of the invention.

Fig. 12

shows a sectional view through an eighth embodiment of the invention.

Fig. 13

shows a sectional view through a ninth embodiment of the invention.

Fig. 14

shows a sectional view through a tenth embodiment of the invention.

Fig. 15

Fig. 4 shows four sectional views and partial plan views in several planes of the embodiment Fig. 14 ,

Fig. 16

shows different discharge angles of an eleventh embodiment of the invention.

The exhaust gas recirculation apparatus according to the first embodiment of the invention ( Fig. 1 ) comprises a designed as a perforated aluminum plate mounting member 2, which is set over a side opening of a compressed combustion air leading channel 1. The determination of the channel can be made arbitrarily, such as by gluing, positive recording or screwing.

The mounting member has a central opening 2a, in which an exhaust pipe 3 made of a temperature-resistant material, such as stainless steel, is introduced, so that the exhaust gas (dashed arrow) flows into the channel for mixing with the combustion air (solid arrows). The position of the inflow into the channel 1 is upstream of a charge air cooler.

At the exhaust pipe 3, a flange 4 is provided, by means of which the mounting member 2 and the exhaust pipe 3 are sealingly connected together. For this purpose, there is a seal 5 between flange 4 and mounting member 2. The flange 4 is by means of screws (not shown), the corresponding bolt holes 4a, 2b pass through the flange and mounting member, releasably secured.

To cool the mounting member, a coolant channel 6 is provided on it, which rotates the opening 2a. The coolant channel 6 is located on the opposite side of the flange 4 and is formed as a round pipe. The coolant channel 6 consists in the present case of aluminum and is soldered flat on the plate 2. Its (not shown) connection to a coolant circuit can be done by simply attaching hoses on its ends 6a. The coolant circuit may be, for example, the cooling circuit of the internal combustion engine or else a separate or connected low-temperature cooling circuit.

• Im Betrieb des Verbrennungsmotors wird ein einstellbarer Teil des Abgasstroms abgezweigt und -gegebenenfalls nach Kühlung in einem (nicht gezeigten) Abgaskühler durch die Abgasleitung 3 der verdichteten Verbrennungsluft in dem Kanal 1 zugeführt. Dabei kann sich die Abgasleitung auf eine hohe Temperatur von mehreren hundert °C erhitzen. Eine Beschädigung des Material des Kanals 1 wird dadurch ausgeschlossen, dass die Abgasleitung im Bereich ihrer Einmündung Wärme an das Kühlmittel in dem Kühlmittelkanal 6 abführt, so dass das Montageglied 2 zumindest im Bereich seiner Berührung mit dem Kanal 1 jederzeit eine unkritische Temperatur aufweist. Durch die Dichtung 5 wird eine zusätzliche Isolation zwischen Montageglied 2 und Abgasleitung 3 geschaffen.

The invention now works as follows:

• During operation of the internal combustion engine, an adjustable part of the exhaust gas flow is branched off and, if necessary, after cooling in an exhaust gas cooler (not shown), is supplied through the exhaust gas line 3 to the compressed combustion air in the channel 1. In this case, the exhaust pipe can be heated to a high temperature of several hundred ° C. Damage to the material of the channel 1 is precluded by the fact that the exhaust pipe in the region of its junction dissipates heat to the coolant in the coolant channel 6, so that the mounting member 2 at any time at least in the region of its contact with the channel 1 has an uncritical temperature. By the seal 5 additional insulation between the mounting member 2 and exhaust pipe 3 is created.

• Im Unterschied zur Ausführung nach Fig. 1 hat hier das Rohr des Kühlmittelkanals 6 einen rechteckigen Querschnitt, so dass eine besonders große Kontaktfläche zwischen Kühlmittelkanal 6 und Montageglied 2 zur Verfügung steht.

Second embodiment ( Fig. 4 ):

• Unlike the execution after Fig. 1 Here, the tube of the coolant channel 6 has a rectangular cross section, so that a particularly large contact area between the coolant channel 6 and mounting member 2 is available.

• Im Unterschied zu den ersten beiden Ausführungsbeispielen wird der Kühlmittelkanal 6 hier von einem auf die Montageplatte aufgesetzten, zum Montageglied 2 hin offenem Blechformteil 6b gebildet, so dass das Montageglied 2 einen Teil der Wand des Kühlmittelkanals 6 ausformt. Das Formteil 6b ist flächig mit der dem Montageglied 2 verbunden, wobei zum Beispiel eines der Teile aus einem lotplattierten Blech geformt sein kann. Fig. 6 zeigt beispielhaft, welchen Verlauf das Blechformteil 6b dem Kühlmittelkanal 6 geben kann. An dem Blechformteil 6b sind zudem Anschlüsse 6a für den Kühlmittelkreis vorgesehen.

Third embodiment ( Fig. 5 ):

• In contrast to the first two embodiments, the coolant channel 6 is here formed by a patch on the mounting plate, the mounting member 2 through open sheet metal part 6b, so that the mounting member 2 forms a part of the wall of the coolant channel 6. The molded part 6b is flat with the mounting member 2, wherein, for example, one of the parts may be formed from a solder-plated sheet metal. Fig. 6 shows by way of example, which course the sheet metal part 6b can give the coolant channel 6. At the sheet metal part 6b terminals 6a are also provided for the coolant circuit.

• Im Unterschied zum dritten Ausführungsbeispiel sind hier Kühlmittelkanal 6 und Flansch 4 auf der gleichen Seite des Montageglieds 2 angeordnet. Der Flansch 4 sitzt dabei mit seiner Dichtung 5 unmittelbar auf dem Blechformteil 6b auf, so dass eine besonders gute und aktiv gekühlte Isolierung zwischen Flansch 4 und Montageglied 2 gegeben ist. In Fig. 7a ist dargestellt, dass das Blechformteil auch aus mehreren Teilstücken 6b, 6c aufgebaut sein kann.

Fourth embodiment ( Fig. 7 . Fig. 7a ):

• In contrast to the third embodiment, here coolant channel 6 and flange 4 are arranged on the same side of the mounting member 2. The flange 4 sits with its seal 5 directly on the sheet metal part 6b, so that a particularly good and actively cooled insulation between flange 4 and 2 mounting member is given. In Fig. 7a is shown that the sheet metal part can also be composed of several sections 6b, 6c.

• Im Unterschied zum dritten Ausführungsbeispiel (siehe etwa Fig. 6) ist hier der Kühlmittelkanal so geformt, dass er die Befestigungsschrauben 2b für den Flansch mit einschließt. Hierdurch werden auch diese Wärmebrücken aktiv gekühlt.

Fifth Embodiment ( Fig. 8 ):

• In contrast to the third embodiment (see, for example Fig. 6 ) Here, the coolant channel is shaped so that it includes the fastening screws 2b for the flange. As a result, these thermal bridges are actively cooled.

• Im sechsten Ausführungsbeispiel ist die erfindungsgemäße Vorrichtung baueinheitlich mit einem indirekten bzw. kühlmitteldurchströmten Ladeluftkühler 7 mit luftumströmten und kühlmitteldurchströmten Flachrohren 9 ausgebildet, der sich in unmittelbarer Nachbarschaft zu der Abgasleitung befindet. Dabei wird ein Boden 8 des Ladeluftkühlers 7 so vergrößert bzw. ausgeformt, dass er eine Öffnung 8a für die Abgasleitung 3 umfasst. Zudem wird ein Sammlerdeckel 10 entsprechend ausgeformt.
• Es kann vorgesehen sein, den Sammlerdeckel 10 bzw. Wasserkasten des Ladeluftkühlers und einen Kühlkanal 6 in einem zum Beispiel tiefgezogenen Blechformteil zu vereinen. Je nach Ausformung ist bei diesem Ausführungsbeispiel nicht notwendig ein Kühlkanal 6 vorgesehen, da eine aktive Kühlung der Abgasleitung 3 bereits aufgrund des Durchgreifens des Sammlers gegeben ist. In den vorliegenden Zeichnungen Fig. 9, Fig. 10 ist allerdings erkennbar ein Kühlmittelkanal 6 mit einem Anschluss 6a ausgeformt, wobei der Anschluss 6a zugleich ein Anschluss des Ladeluftkühlers an den Kühlmittelkreislauf ist.

Sixth embodiment ( Fig. 9, Fig. 10 ):

• In the sixth embodiment, the device according to the invention is constructed in a unitary manner with an indirect or coolant-flow intercooler 7 with air-flowed and coolant-flow-through flat tubes 9, which are located in the immediate vicinity of the Exhaust pipe is located. In this case, a bottom 8 of the intercooler 7 is enlarged or formed so that it comprises an opening 8a for the exhaust pipe 3. In addition, a collector cover 10 is formed accordingly.
• It can be provided to combine the header cover 10 or water tank of the intercooler and a cooling channel 6 in a deep-drawn sheet metal part, for example. Depending on the shape of a cooling duct 6 is not necessarily provided in this embodiment, since an active cooling of the exhaust pipe 3 is already given due to the punching through of the collector. In the present drawings Fig. 9, Fig. 10 However, it is evident that a coolant channel 6 is formed with a connection 6a, wherein the connection 6a is at the same time a connection of the intercooler to the coolant circuit.

• Fig. 11 zeigt eine dem Beispiel aus Fig. 9, Fig. 10 ähnliche Ausführungsform der Erfindung, bei der die Abgasleitung 3 unmittelbar in einen Ladeluftkühler 7 mündet. Ein Flansch 4 der Abgasleitung 3 sitzt auf einem Sammlerkasten 10 dichtend auf, wobei der Sammlerkasten 10 eine von der Abgasleitung 3 durchgriffene und nicht vom Kühlmittel umströmte Ausnehmung 11 umläuft. Bei diesem Beispiel kann der Sammlerkasten 10 insgesamt als Kühlmittelkanal für die Abgasleitung angesehen werden.

Seventh embodiment ( Fig. 11 ):

• Fig. 11 shows an example Fig. 9, Fig. 10 Similar embodiment of the invention, in which the exhaust pipe 3 opens directly into a charge air cooler 7. A flange 4 of the exhaust pipe 3 is seated on a collector box 10 sealingly, wherein the collector box 10 rotates a swept by the exhaust pipe 3 and not flowed around by the coolant recess 11. In this example, the header box 10 may be considered as a whole as a coolant passage for the exhaust pipe.

In addition, the protruding into the intercooler 7 exhaust pipe 3 is formed as a pipe section 12 having a plurality of radially directed exhaust ports 13 for the exhaust gas. As a result, the exhaust gas is divided into a plurality of small partial flows, so that local overheating of components of the charge air cooler 7 is avoided. In principle, such a pipe section 12 can also lead, while maintaining these advantages, into a simple channel 1, see, for example, the first exemplary embodiment.

In the present case, the pipe section 12 is closed at the end, being received with its closed end in a seal 14 in an opening of the bottom 8 opposite the inlet side 8 '. Of course, depending on the construction, the pipe section can also protrude freely into the intercooler 7.

• Beim achten Ausführungsbeispiel liegt im Unterschied zum siebten Ausführungsbeispiel eine Verzweigung der Abgasleitung in mehrere, vorliegend drei, Rohrabschnitte 12 vor, wodurch eine noch stärker verteilte Ausströmung des Abgases erreicht wird. Die Verzweigung erfolgt innerhalb des Ladeluftkühlers hinter der Ausnehmung 11 bzw. dem eintrittsseitigen Boden 8.

Eighth embodiment ( Fig. 12 ):

• In the eighth exemplary embodiment, in contrast to the seventh exemplary embodiment, a branching of the exhaust gas line into a plurality of, in the present case three, tube sections 12 occurs, as a result of which an even more distributed outflow of the exhaust gas is achieved. The branching takes place inside the charge air cooler behind the recess 11 or the inlet-side bottom 8.

• Dieses Beispiel betrifft eine Weiterentwicklung einer Abgasleitung 3 mit Rohrabschnitt 12 wie im Beispiel nach Fig. 11. Vorliegend sind die Ausströmöffnungen 13 über den Verlauf des Rohrabschnitts 12 mit zunehmender räumlicher Dichte (siehe obere Schnittkante des Rohrabschnitts 12) oder auch mit bei gleichem Abstand zunehmender Querschnittsfläche (siehe untere Schnittkante des Rohrabschnitts 12) ausgebildet. In jedem Fall ist hierdurch erreicht, dass ein hydraulischer Ausströmquerschnitt pro Längeneinheit des Rohrabschnitts 12 in der Strömungsrichtung zunimmt, so dass der mit der Ausströmung verbundene Druckabfall des Abgases kompensiert wird. Insgesamt wird hierdurch ein gleichmäßigerer Massenstrom des ausströmenden Abgases über die Länge des Rohrabschnitts 12 erzielt.

Ninth Embodiment ( Fig. 13 ):

• This example relates to a further development of an exhaust pipe 3 with pipe section 12 as in the example Fig. 11 , In the present case, the outflow openings 13 are formed over the course of the pipe section 12 with increasing spatial density (see upper cut edge of the pipe section 12) or with an increasing cross-sectional area at the same distance (see lower cut edge of the pipe section 12). In any case, this achieves the result that a hydraulic outflow cross section per unit length of the pipe section 12 increases in the flow direction, so that the pressure drop of the exhaust gas associated with the outflow is compensated. Overall, this results in a more uniform mass flow of the outflowing exhaust gas over the length of the pipe section 12.

• Als weitere Möglichkeit der Beeinflussung der Abgasausströmung sind in im Beispiel nach Fig. 14 Strömungshindernisse 15 über zumindest einigen der Ausströmöffnungen 13 vorgesehen. Die Strömungshindernisse 15 sind vorliegend als aufgeschobene Blechringe ausgebildet, die an den Stellen der Überdeckung mit den Ausströmöffnungen 13 definiert dimensionierte und aufgestellte Laschen umfassen. Je nach Position an Rohrabschnitt 12 sind die Laschen bzw. Strömungshindernisse 15 unterschiedlich geformt und/oder aufgestellt. Fig. 15 zeigt zur Verdeutlichung vier Schnitte durch die vier in Fig. 14 gezeigten Blechringe nebst jeweiligem Ausschnitt einer Draufsicht auf die Laschen.

Tenth embodiment ( Fig. 14, Fig. 15 ):

• As a further possibility of influencing the exhaust gas outflow are in the example after Fig. 14 Flow obstacles 15 over at least some the discharge openings 13 are provided. In the present case, the flow obstacles 15 are designed as pushed-on sheet-metal rings which, at the points of overlap with the outflow openings 13, comprise dimensioned and erected tabs. Depending on the position of the pipe section 12, the tabs or flow obstacles 15 are shaped differently and / or placed. Fig. 15 shows for clarity four sections through the four in Fig. 14 shown metal rings together with respective section of a plan view of the tabs.

• In Fig. 16 werden die Strömungen von Ladeluft (durchgezogene Linien) und aus einem Rohrabschnitt 12 einströmendem Abgas (gestrichelte Linien) dargestellt, wobei die Ausströmöffnungen jeweils unter verschiedenen Winkeln zur Symmetrieebene bzw. Hauptströmungsrichtung der Ladeluft angeordnet sind.

Eleventh Embodiment of the Invention ( Fig. 16 ):

• In Fig. 16 the flows of charge air (solid lines) and from a pipe section 12 inflowing exhaust gas (dashed lines) are shown, wherein the outflow openings are each arranged at different angles to the plane of symmetry or main flow direction of the charge air.

It will be appreciated that both at too small angles (e.g., 0 °) and too large angles (e.g., 180 °), a relatively compact exhaust plume is formed. This means a poorer mixing and the risk of local overheating of components of the charge air duct or intercooler.

Preferably, therefore, an angle to the geometric flow direction of the charge air (in the figures horizontally from right to left) is selected for the outflow 13, which is between 45 ° and 135 °, preferably between 90 ° and 135 °.

It is understood that all individual features of the embodiments described above can be meaningfully combined with each other depending on the requirements. In particular, the provision of a pipe section 12 with a plurality of outflow openings 13 with its respective detailed developments with any of the embodiments combined. In a possible embodiment of the invention, it is not necessarily provided that the exhaust pipe 3 is cooled with the pipe section 12 by a coolant. By the pipe section 12 per se, a more uniform distribution of the hot exhaust gas over a larger spatial area can be done, so that a critical heat exposure is avoided, for example, on a channel wall.

Claims (16)

Exhaust gas recirculation device for an internal combustion engine, comprising
an exhaust pipe (3) for guiding exhaust gas, and
a duct (1) for supplying air to the internal combustion engine,
wherein the exhaust pipe (3) opens into the channel (1),
characterized,
that the exhaust line (3) in an area of its inlet to the duct (1) in heat exchange communication with a coolant flowing in a coolant circuit. Apparatus according to claim 1, characterized in that the exhaust pipe (3) with a mounting member (2), in particular of metal, is connected, wherein the coolant flows through a provided on the mounting member (2) coolant channel (6). Apparatus according to claim 2, characterized in that the exhaust pipe (3) has a with the mounting member (2) connectable flange (4). Device according to Claim 3, characterized in that a seal (5) is arranged between the flange (4) and the mounting member (2). Device according to one of claims 2 to 4, characterized in that the coolant channel (6) as with the mounting member (2) in particular cohesively connected pipe is formed. Device according to one of claims 2 to 4, characterized in that the coolant channel (6) as with the mounting member (2) in particular cohesively connected, single or multi-piece sheet metal part (6a, 6b) is formed. Device according to one of the preceding claims, characterized in that the region of the mouth of the exhaust pipe (3) is provided on a charge air cooler (7) through which the coolant flows. Apparatus according to claim 7, characterized in that the region of the confluence on a coolant-side header member (10) of the charge air cooler (7) is arranged. Device according to one of claims 1 to 6, characterized in that the exhaust pipe (3) opens upstream of a charge air cooler (7) in the channel (1). Device according to one of the preceding claims, characterized in that the channel (1) is formed at least in the region of the mouth of the exhaust pipe (3) made of a plastic. Device according to one of the preceding claims, further comprising the characterizing features of one of the subsequent claims. Exhaust gas recirculation device for an internal combustion engine, comprising
an exhaust pipe (3) for guiding exhaust gas, and
a duct (1) for supplying air to the internal combustion engine,
wherein the exhaust pipe (3) opens into the channel (1),
characterized,
that the exhaust line (3) in an area of its inlet to the duct (1) as at least one pipe section (12) is formed, wherein a plurality of outflow openings (13) for the exhaust gas along the pipe section (12). Apparatus according to claim 12, characterized in that the exhaust pipe (13) branches in the region of their confluence in a plurality of pipe sections (12). Apparatus according to claim 12 or 13, characterized in that the outflow openings (13) are distributed over number and / or size over a length of the pipe section (12) that a hydraulic Ausströmquerschnitt per unit length of the pipe section (12) in the flow direction of the exhaust gas increases. Device according to one of claims 12 to 14, characterized in that flow obstacles (15) are arranged on at least some of the outflow openings (13). Device according to one of claims 12 to 15, characterized in that the outflow openings (13) at least are aligned predominantly in an outflow angle of between 45 ° and 135 °, in particular between 90 ° and 135 °, to a main flow direction of the air in the channel (1).

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