EP3203048A1 - Fixing assembly for fixing an exhaust manifold on a cylinder head of a combustion engine - Google Patents

Abstract

In the case of a fastening arrangement for securing an exhaust manifold (12) on a cylinder head (14) of an internal combustion engine, the exhaust manifold (12) has an essentially planar first contact surface (20) for support with respect to an essentially planar second contact surface (22) of the cylinder head (14). the outlet manifold (12) having in a first fastening edge region (16) a wedge-like first fastening flange region (24) with a first fastening element support surface (26) inclined with respect to the first contact surface (20) at a first wedge angle (W 1), a first Fastening element (38) by means of at least one first fastening bolt unit (30) which is supported or can be supported with respect to the cylinder head (14) and has a first fastening flange support surface (40) against the first fastening element support surface (26), wherein for the first wedge angle (W 1) and a coefficient of static friction (µ) of R. The following applies to the interaction of the first fastening element (38) with respect to the exhaust manifold (12): 0 <W 1 ‰ ¤ 2 tan ˆ ’1 µ, where: W 1 is the first wedge angle, µ is the coefficient of static friction.

Description

The present invention relates to a fastening arrangement for fixing an exhaust manifold to a cylinder head of an internal combustion engine.

In internal combustion engines used in automobiles, which are generally constructed as multi-cylinder internal combustion engines with at least one row of cylinders formed in a cylinder block, an exhaust manifold of an elongated cylinder along the row of cylinders and thus the exhaust gases exiting therefrom is generally located on an exhaust side of the cylinder head also referred to as exhaust manifold defined. The exhaust manifold has a substantially planar bearing surface, which is supported with the intermediate storage of a sealing element with respect to a likewise substantially planar bearing surface of the cylinder head. The exhaust manifold has on its longitudinal sides respective fastening edge regions. By fixed to the cylinder head, for example by screw fastening bolt units are supported on the fastening edge areas supporting fasteners against the mounting edge areas or respectively provided Befestigungselementenabstützflächen or against the cylinder head, so that the Auslasskrümmer is pressed against the contact surface of the cylinder head, of course, with intermediate storage of the already mentioned sealing element for the production of a gastight seal.

For structural reasons, it may be necessary to arrange on at least one of the fastening edge regions with respect to the cylinder head on the one hand and a fastener on the other hand supporting mounting bolt units not orthogonal to the contact surface of the cylinder head, but inclined to access in fixing the Auslasskrümmers on the cylinder head access to the fastening bolt units to have. This inclined arrangement of the fastening bolt units on at least one of the fastening edge regions requires a wedge-like configuration of a fastening flange region provided on this fastening edge region, against which the fastening element pressed by these fastening bolt units against the fastening edge region is supported. Due to this inclined arrangement of the fastening bolt units and the wedge-like design of the fastening flange region, transverse forces arise which load the exhaust manifold in the direction of its other fastening edge region or fastening bolt units provided there and the fastening element provided there.

During operation of an internal combustion engine, the exhaust manifold, like the cylinder head, is subject to high thermal and mechanical stress. Due to the thermally induced expansions or contractions occurring at the beginning of an internal combustion operation and after the end of a combustion operation, forces repeatedly occur in the region of the attachment of the exhaust manifold to the cylinder head, which also heavily load the fastening bolt units used to fix the exhaust manifold on the cylinder head and, as well supported by the vibrations occurring in the combustion operation, can lead to the loosening of fastening bolt units and a deviating from a desired mounting position of the exhaust manifold with respect to the cylinder head installation position.

It is the object of the present invention to provide a fastening arrangement for fixing an exhaust manifold to a cylinder head of an internal combustion engine, which ensures stable under strong thermal and mechanical stress and secured against undefined movements fixing the exhaust manifold on the cylinder head.

wobei:

• W₁ der erste Keilwinkel ist,
• µ der Haftreibungskoeffizient ist.

According to the invention, this object is achieved by a fastening arrangement for fixing an exhaust manifold to a cylinder head of an internal combustion engine, wherein the exhaust manifold has a substantially plane first contact surface for support with respect to a substantially planar second contact surface of the cylinder head, wherein the exhaust manifold in a a first fastening flange portion having a first Befestigungselementenabstützfläche inclined with respect to the first bearing surface with a first wedge angle, wherein a first fastening element by means of at least one with respect to the cylinder head is supported or supportable first fastening bolt unit with a first Befestigungsflanschabstützfläche pressed against the first Befestigungselementenabstützfläche or pressed, wherein for the first wedge angle and a coefficient of static friction of the frictional interaction of the first fastener with respect to the exhaust manifold: $$\mathrm{0}<{\mathrm{W}}_{\mathrm{1}}\le \mathrm{2}{\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right).$$

in which:

• W _{1 is} the first wedge angle,
• μ is the static friction coefficient.

By selecting the first wedge angle in the aforementioned range, it is ensured that the forces oriented essentially parallel to the mutually prestressed support surfaces of the exhaust manifold on the one hand and of the cylinder head on the other hand, due to the wedge-like configuration of the first mounting flange region, result in a transverse load or transverse displacement the exhaust manifold with respect to the cylinder head could occur only in a friction cone not significantly exceeding extent. This limitation of the displacement forces acting on the exhaust manifold ensures that undesired displacement of the exhaust manifold or unwanted loosening of the fastening bolt units will not occur even if the thermal and mechanical loads repeatedly occur.

vorzugsweise $${\mathrm{W}}_{\mathrm{1}}={\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right)\mathrm{.}$$

In a particularly advantageous embodiment, it may be provided that the following applies for the first wedge angle and the static friction coefficient: $$\mathrm{0}<{\mathrm{W}}_{\mathrm{1}}\le {\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right).$$

preferably $${\mathrm{W}}_{\mathrm{1}}={\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right)\mathrm{,}$$

In this way it can be ensured that the forces exerted on the exhaust manifold in the direction of displacement forces are kept so low that they can not exceed the static friction forces occurring between the first mounting flange and the first fastener and thus by the means of the first mounting bolt units forces exerted on the exhaust manifold induced transverse displacement of the exhaust manifold can not occur minimized.

In an alternative embodiment in which the frictional friction forces resulting from frictional interaction are permitted to exceed slightly transverse forces, it is proposed that the following apply to the first wedge angle and the static friction coefficient: $${\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right)<{\mathrm{W}}_{\mathrm{1}}\le \mathrm{2}{\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right)\mathrm{,}$$

For a transverse forces also substantially excluding Abstützwechselwirkung between the first fastening element and the at least one first fastening bolt unit, it is proposed that the first fastening element to a first fastening bolt longitudinal axis of the at least one first fastening bolt unit substantially orthogonal first Befestigungsbolzeneinheitabstützfläche for supporting the at least one first fastening bolt unit with respect to the first Has fastening element.

In order to ensure access to the at least one first fastening bolt unit for the assembly of the exhaust manifold, it is proposed that a first fastening bolt longitudinal axis of the at least one first fastening bolt unit with a first longitudinal axis angle with respect to the second contact surface starting from the cylinder head towards a free end of the first mounting flange is inclined to, preferably in the range between 50 ° and 70 °, most preferably about 60 °. It lies Preferably, the first fastening bolt longitudinal axis of the at least one first fastening bolt unit in a plane substantially orthogonal to the second bearing surface, which means that this first fastening bolt longitudinal axis substantially only outwardly, ie in the direction away from the exhaust manifold and toward the free end of the first mounting flange is inclined, but not in the direction of the longitudinal extent of the exhaust manifold, in which it extends along the row of cylinders in a cylinder block, is inclined.

Furthermore, in order to avoid transverse displacements between these two modules, ie displacements substantially transversely to the fastening bolt longitudinal axis of this at least one first fastening bolt unit, in the interaction between the at least one fastening bolt unit and the first fastening element, it is further proposed that a fastening bolt of the at least one first fastening bolt unit has a fastening bolt through opening the first fastening element passes through transversely to the first fastening bolt longitudinal axis substantially without movement play.

In order to ensure a stable connection thereof to the cylinder head on the other side of the exhaust manifold, it is proposed that the exhaust manifold in a second fastening edge region have a second fastening flange region oriented substantially opposite the first fastening flange region and having a second inclined with respect to the first contact surface with a second wedge angle Fastening element support surface, wherein a second fastening element by means of at least one with respect to the cylinder head is supported or supportable second fastening bolt unit pressed against the cylinder head or pressable and identifies a relative to the second bearing surface with the second wedge angle inclined second Befestigungsflanschabstützfläche. The second fastening element can be fixed to the cylinder head prior to attachment of the exhaust manifold so that the exhaust manifold with its likewise wedge-like second fastening flange region is pushed under the second fastening element can be and subsequently carried out at the first attachment edge portion a determination by means of the first fastener.

Advantageously, a second fastening bolt longitudinal axis of the at least one second fastening bolt unit is arranged with respect to the second contact surface with a second longitudinal axis angle, wherein the second longitudinal axis angle is in the range of 90 °.

The second wedge angle is preferably greater than the first wedge angle, and the second fastening element may comprise a second fastening bolt unit supporting surface substantially orthogonal to the second fastening bolt longitudinal axis of the at least one second fastening bolt unit for supporting the at least one second fastening bolt unit with respect to the second fastening element.

In order to be able to absorb the high thermal and mechanical loads occurring during combustion, the exhaust manifold may be made of steel, preferably ST52. The first fastening element which comes into frictional interaction with the exhaust manifold can also be made of steel, preferably also ST52. The coefficient of static friction acting between the exhaust manifold and the cylinder head is, for example, in the range from 0.10 to 0.14, preferably in the range from 0.11 to 0.13, in particular when steel material is used to build up these assemblies.

The invention further relates to an internal combustion engine, in particular for a vehicle, comprising a cylinder head fixed to a cylinder block and an exhaust manifold fixed to the cylinder head by means of a fastening arrangement according to the invention.

Fig. 1

eine prinzipartige Querschnittansicht eines in einem ersten Befestigungsrandbereich mit einem Zylinderkopf verbundenen Auslasskrümmers;

Fig. 2

eine der Fig. 1 entsprechende Darstellung, welche die Festlegung des Auslasskrümmers am Zylinderkopf in einem zweiten Befestigungsrandbereich des Auslasskrümmers zeigt.

In the following, the invention will be described in detail with reference to the attached figures. It shows:

Fig. 1

a principle cross-sectional view of a connected in a first fastening edge region with a cylinder head exhaust manifold;

Fig. 2

one of the Fig. 1 corresponding representation showing the determination of the exhaust manifold on the cylinder head in a second fastening edge region of the exhaust manifold.

The Fig. 1 and 2 show in simplified representation a generally designated 10 mounting arrangement, by means of which an exhaust manifold 12 can be fixed to a cylinder head 14 of an internal combustion engine. It shows the Fig. 1 the determination of the exhaust manifold 12 on the cylinder head 14 in a first fastening edge region 16 of the exhaust manifold 12, while the Fig. 2 the determination of the exhaust manifold 12 on the cylinder head 14 in a second fastening edge region 18 of the exhaust manifold 12 shows. It should be noted that the exhaust manifold 12 is basically orthogonal to the planes of the drawing Fig. 1 and 2 may be elongate and extend with its longitudinal direction along the cylinder provided in a cylinder block.

The exhaust manifold 12 has a planar first contact surface 20, which faces a second abutment surface 22 of the cylinder head 14. As described below, the exhaust manifold 12 is urged toward the second abutment surface 22, with a seal member, not shown in the figures, being positioned between the first abutment surface 20 and the second abutment surface 22 to obtain a gas tight seal.

In the first fastening edge region 16, the outlet manifold 12 has a wedge-like first fastening flange region 24. This is limited in the direction of the cylinder head 14 through the first contact surface 20 and is limited in the direction away from the cylinder head 14 by a Befestigungselementenabstützfläche 26. Between the first contact surface 20 and the first Befestigungselementenabstützfläche 26, a first wedge angle W _{1 is} formed, so that the first mounting flange portion 24 is tapered toward a free end 28 thereof.

For fixing the exhaust manifold 12 in its first fastening edge region 16 on the cylinder head 14, it is preferable to have a plurality of in the longitudinal extension direction of the exhaust manifold 12, that is to say orthogonal to the plane of the drawing Fig. 1 successive first fastening bolt units 30 are provided. Each of these first fastening bolt units 30 comprises a fastening bolt 32, also generally referred to as stud bolt, which is inserted into an associated opening 34 in the cylinder head 14, preferably screwed. The fastening bolt 32 is therefore preferably designed as an external thread bolt, and the receiving opening 34 in the cylinder head 14 is designed as an internal thread opening.

In association with each first fastening bolt unit 30, in the first fastening flange region 24, for example, a fastening bolt through opening 36 which is open towards the free end 28 of the same is formed. By means of this fastening bolt passage opening 36, the fastening bolt 32 extends outward from the cylinder head 14 with its first fastening bolt longitudinal axis A ₁ at a first longitudinal axis angle L ₁ with respect to the second contact surface 22, ie in the direction away from the exhaust manifold 12 or in the direction of the free end 28 of FIG first mounting flange portion 24 to inclined. In this case, the first fastening bolt longitudinal axis A ₁ preferably lies in a position orthogonal to the second contact surface 22, and thus substantially also the plane of the drawing Fig. 1 appropriate level. The fastening bolt 32 thus has no inclination angle component in the direction of the longitudinal extent of the exhaust manifold 12.

The fastener assembly 10 also includes a first fastener 38 associated with the first fastener flange portion 24. The first fastener 38 preferably extends across the entire first fastener rim portion 16 in the direction of the longitudinal extent of the exhaust manifold 12 and thus acts with those therein Longitudinal direction of the exhaust manifold 12 successive first fastening bolt units 30 together.

The first attachment element 38 has a first attachment flange support surface 40, with which it bears against the first attachment element support surface 26 of the first attachment flange region 24. Assigned to each first fastening bolt unit 30, the first fastening element 38 has a fastening bolt through-opening 42, in which a respective fastening bolt 32 is received transversely to its first fastening bolt longitudinal axis A ₁ substantially without play. Thus, the most accurate fit is provided, which on the one hand enables the first fastening element 38 to be pushed onto the fastening bolts 32, but on the other hand does not substantially permit transverse displacements of the first fastening element 38 with respect to the fastening bolts 32.

At the side facing away from the first mounting flange region 24 and thus the first fastening element support surface 28, the first fastening element 38 has a fastening bolt unit support surface 44. At this fixing bolt unit support surface 44 oriented essentially orthogonally with respect to the first fastening bolt longitudinal axis A ₁ , a fastening nut 46 standing or engageable in threaded engagement with the fastening bolt 32 can be supported either directly or via an insert disk element. As a result of this fastening nut 46, when the same is applied to the first fastening element 48, a force directed essentially in the direction of the first fastening bolt longitudinal axis A ₁ and thus correspondingly inclined to the second contact surface 22 is exerted, which the first fastening element 38 against the first mounting flange region 24, thus the first Mounting flange support surface 40 against the first fastener support surface 26 presses.

Also in the in Fig. 2 illustrated second mounting edge portion 18, the exhaust manifold 12 has a substantially wedge-like second mounting flange 48. The second mounting flange 48 has a at a second wedge angle W ₂ with respect to the first contact surface 20 and thus also the second contact surface 22 inclined second Befestigungselementenabstützfläche 50 on. Also, the second mounting flange portion 48 is tapered toward its free end 52 and is thus oriented substantially opposite to the first mounting flange portion 24.

Associated with the second mounting flange portion 48, the mounting assembly 10 includes a second fastener 54. This is defined by a plurality of in the direction of the longitudinal extent of the exhaust manifold 12 successive second mounting bolt units 56 on the cylinder head 14. Each second mounting bolt unit 56 includes a mounting bolt 58 which is inserted into an associated opening of the cylinder head 14, preferably held therein by threaded engagement. The fastening bolts 58 of the second fastening bolt units 56 are thus preferably designed as external thread bolts, while the openings receiving these are formed in the cylinder head 14 as internal threaded openings. It can be seen in Fig. 2 in that the fastening bolts 58 with their second fastening bolt longitudinal axes A _{2 are arranged} with respect to the second contact surface 22 with a second longitudinal axis angle L ₂ of 90 °. The fastening bolts 58 thus extend substantially orthogonally with respect to the second contact surface 22 and also have no inclination angle components in the direction of the longitudinal direction of the exhaust manifold 12.

On a side remote from the second contact surface 22 of the cylinder head 14 side, the fastening element 54 on a second Befestigungsbolzeneinheitabstützfläche 60, the respective second mounting bolt longitudinal axis A _{2 of} the mounting bolt 58 in Substantially orthogonal and at which a threaded engagement with the fastening bolt 58 of a respective second fastening bolt unit 56 standing or bringable fastening nut 62 either directly or with intermediate storage of a Shim is supported or supportable. By the fastening nuts 62 of the second fastening bolt units 56, the second fastening element 54 is pressed with a Zylinderkopfabstützfläche 64 against the second bearing surface 22 of the cylinder head 14. The second fastening element 54 is thus held in a defined position relative to the cylinder head 14 by means of the second fastening bolt units 56. For this purpose, for example, the fastening bolt through openings for the fastening bolts 58 of the second fastening bolt units 56 formed in the second fastening element 54 have a dimensioning such that the fastening bolts 58 are again received transversely to their second fastening bolt longitudinal axes A ₂ essentially without movement play in these fastening bolt through openings, so that the second fastening element 54 is held substantially immovable not only in the direction orthogonal back to the receiving surface 22, but also in the direction parallel to the second bearing surface 22 in a defined position.

Associated with the second mounting flange portion 48 of the exhaust manifold 12, a second mounting flange support surface 66 is provided on the second fastener 54. This is inclined with respect to the second contact surface 22 and thus also the first contact surface 20 with the second wedge angle W ₂ , with which also the second Befestigungselementabstützfläche 50 of the second mounting flange 48 is inclined with respect to these surfaces. Thus, between the second Befestigungsflanschabstützfläche 66 and the second abutment surface 22, a wedge-like undercut is formed, in which the second mounting flange 48 can be positioned engaging. Due to the coincident angling of the two surfaces 50, 66, the second fastening element 54 and the exhaust manifold 12 abut one another in the region of these surfaces to produce a uniform contact surface contact. Where, in the longitudinal direction of the exhaust manifold 12, the fastening bolts 58 of the second fastening bolt units 56 extend out of the cylinder head 14, open recesses may be formed in the second mounting flange area 48 towards the free end 52, into which the fastening bolts 58 partially engage or through which the fastening bolts 58 may extend therethrough.

In order to be able to absorb the thermal and mechanical loads occurring during operation and to ensure a stable connection of the exhaust manifold 12 to the cylinder head 14, the exhaust manifold 12 and the two fastening elements 38, 54 are preferably made of steel material, for example ST52. The cylinder head 14 is constructed, for example, of aluminum material. The fastening bolt units 30, 56, in particular the fastening bolts 32, 58 of the same, are preferably also constructed of steel material, which also in the Abstützwechselwirkung with the cylinder head 14 on the one hand and the fastener 38, 54 on the other hand, the required connection strength and load capacity of the fastening bolts 32, 58 also guaranteed transversely to their mounting bolt longitudinal axes A ₁ , A ₂ .

To attach the exhaust manifold 12 to the cylinder head 14, it is possible, for example, to proceed by first inserting the fastening bolts 58 of the second fastening bolt units 56, possibly also the fastening bolts 32 of the first fastening bolt units 30, into the cylinder head 14 with the required installation depth. Subsequently, the second fastening element is pushed onto the fastening bolts 58 and pressed by the fastening nuts 62 of the second fastening bolt units 56 against the second contact surface 22 of the cylinder head 14. Unless already done, then the fastening bolts 32 of the first mounting bolt units 30 are introduced with the required installation depth in the cylinder head 14, so screwed, for example. Then, the sealing element, not shown in the figures, is placed on the second contact surface 22, so that it lies substantially between the two rows of fastening bolts 32, 58 at the intended position for installation. Subsequently, the exhaust manifold 12 is moved towards the cylinder head 14 such that the second mounting flange portion 18 engages with its second fastener support surface 50 below the second mounting flange support surface 66 of the second fastener 54.

In the course of this process, the exhaust manifold 12 may be pivoted such that its first abutment surface 20 approaches the second abutment surface 22 and the sealing element positioned thereon. During this movement, the first mounting flange portion 24 with the fastener bolt through holes 36 formed thereon moves over the mounting bolts 32 of the first mounting bolt units 30 until the exhaust manifold 12 is supported flatly with respect to the cylinder head 14, ie, the two abutment surfaces 20, 22 are substantially interposed therebetween are positioned parallel to each other.

Subsequently, the first fastener 38 is pushed with its Befestigungsbolzendurchgriffsöffnungen 42 on the mounting bolts 32 of the first mounting bolt units 30 and thus the first fastener 38 with its first Befestigungsflanschabstützfläche 40 on the first Befestigungselementenabstützfläche 26 fitting. By applying and tightening the fastening nuts 46 of the first fastening bolt units 30, the first fastening element 38 is pressed against the first fastening flange region 24. Due to the inclination of the fastening bolts 32 and due to the wedge-like configuration of the second mounting flange portion 24, forces can thereby arise, which the exhaust manifold 12 in the two representations of Fig. 1 and 2 each to the left, so in the direction of the cylinder head 14 fixed second fastener 24 to apply or move.

In order to avoid the occurrence of excessively large transverse forces, that is to say the exhaust manifold 12, forces acting essentially transversely to the cylinder head 14, according to the principles of the present invention, the first wedge angle W ₁ is selected such that the following condition is met: $$\mathrm{0}<{\mathrm{W}}_{\mathrm{1}}\le \mathrm{2}{\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right)\mathrm{,}$$

Here μ is in the region of the adjacent first
Fastener support surface 26 and first Befestigungsflanschabstützfläche 40 occurring static friction coefficient, also called coefficient of friction. This is essentially determined by the construction materials of the two abutting with these surfaces 26, 40 components Auslasskrümmer 12 and first fastener 38. As indicated above, these two components are preferably constructed of steel material, such as ST52, so that in this area Mutual investment will result in a static coefficient of friction in the range of 0.11 to 0.13. Considering this, for the first wedge angle W ₁ , according to the principles of the present invention, it is not greater than twice the inverse tangent of this static friction coefficient. For the mentioned material pairing, an upper limit value for this first wedge angle W ₁ in the range of approximately 14.81 ° thus results for a static friction coefficient of, for example, 0.13. In a particularly preferred embodiment, however, this first wedge angle W ₁ should not be greater than the simple inverse tangent of the static friction coefficient, that is should not be greater than 7.41 °.

When selecting the first wedge angle W ₁ in the above-mentioned range and in particular also such that the second wedge angle W _{2 is} greater than the first wedge angle W ₁ , the occurrence of excessively large forces, which is excessively strong, especially in a thermal expansion or contraction Displacement of the exhaust manifold 12 can lead in the direction of the second fastener 54 avoided. By avoiding excessive displacement, it is also avoided that the various fastening bolt units, in particular the first fastening bolt units 30, due to a displacement of the first mounting flange portion 24 relative to the first fastening element 38 in the illustration of Fig. 1 be loosened to the left or a required tightening torque is not maintained even over a longer period of operation. Nevertheless, the wedge-like configuration, in particular of the first attachment flange portion 24, enables the thermally induced expansions or contractions of the various components that unavoidably occur during operation of an internal combustion engine without an undefined, excessive relative movement between the exhaust manifold 12 and the cylinder head 14 or a loosening of the fastening bolt units.

In a particularly preferred embodiment, it may be provided that the first wedge angle W ₁ essentially corresponds to the inverse tangent of the static friction coefficient μ. In this case, therefore, the first wedge angle W ₁ essentially corresponds to the friction angle or friction cone angle. Thus, it can be ensured that significant lateral forces, which lead to a displacement of the cylinder head 14, do not occur. If the first wedge angle W ₁ is chosen so that it is slightly larger than the inverse tangent of the coefficient of static friction μ, although limited transverse forces can occur, excessive loading of the cylinder head 14 in the transverse direction is avoided.

It should finally be noted that the inventive design of a mounting arrangement or an internal combustion engine constructed therewith can be realized in a particularly advantageous manner, especially where there are large mechanical and thermal loads during operation, ie where the exhaust manifold is fixed to the cylinder head. In principle, however, such a fastening arrangement could also be used for fixing an intake manifold to a cylinder head.

Claims (11)

An attachment assembly for securing an exhaust manifold (12) to a cylinder head (14) of an internal combustion engine, the exhaust manifold (12) having a substantially planar first abutment surface (20) for support relative to a substantially planar second abutment surface (22) of the cylinder head (14) wherein the exhaust manifold (12) has a wedge-like first mounting flange portion (24) in a first mounting edge portion (16) with a first fastener support surface (26) inclined with respect to the first contact surface (20) at a first wedge angle (W ₁ ), wherein a first fastener (38) by means of at least one with respect to the cylinder head (14) supporting or supportable first fastening bolt unit (30) with a first Befestigungsflanschabstützfläche (40) against the first Befestigungselementenabstützfläche (26) is pressed or pressed, wherein for the first wedge angle (W ₁ ) and a static friction coefficient duck (μ) of the frictional interaction of the first fastener (38) with respect to the exhaust manifold (12): $$\mathrm{0}<{\mathrm{W}}_{\mathrm{1}}\le \mathrm{2}{\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right).$$

in which: W _{1 is} the first wedge angle, μ is the static friction coefficient. Fastening arrangement according to claim 1, characterized in that for the first wedge angle (W ₁ ) and the static friction coefficient (μ): $$\mathrm{0}<{\mathrm{W}}_{\mathrm{1}}\le {\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right).$$

preferably $${\mathrm{W}}_{\mathrm{1}}={\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right)\mathrm{,}$$

Fastening arrangement according to claim 1, characterized in that for the first wedge angle (W ₁ ) and the static friction coefficient (μ): $${\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right)<{\mathrm{W}}_{\mathrm{1}}\le \mathrm{2}{\tan }^{-\mathrm{1}}\left(\mathrm{\mu }\right)\mathrm{,}$$

Fastening arrangement according to one of claims 1-3, characterized in that the first fastening element (38) to a first fastening bolt longitudinal axis (A ₁ ) of the at least one first fastening bolt unit (30) substantially orthogonal first Befestigungsbolzeneinheitabstützfläche (44) for supporting the at least one first Fastening bolt unit (30) with respect to the first fastening element (38). Fastening arrangement according to one of claims 1-4, characterized in that a first fastening bolt longitudinal axis (A ₁ ) of the at least one first fastening bolt unit (30) with a first longitudinal axis angle (L ₁ ) with respect to the second bearing surface (22) starting from the cylinder head (14). towards a free end (28) of the first mounting flange portion (24) is inclined, preferably in the range between 50 ° and 70 °, most preferably about 60 °, and / / that a first fastening bolt longitudinal axis (A ₁ ) of the at least a first fastening bolt unit (30) lies in a plane substantially orthogonal to the second contact surface (22), and / or a fastening bolt (32) of the at least one first fastening bolt unit (30) has a fastening bolt penetration opening (42) in the first fastening element (38) in FIG Substantially traversed without movement play transversely to the first mounting bolt longitudinal axis (A ₁ ). Fastening arrangement according to one of claims 1-5, characterized in that the Auslasskrümmer (12) in a second fastening edge region (18) a the first mounting flange portion (24) substantially opposite oriented second Mounting flange (48) having a relative to the first contact surface (20) with a second wedge angle (W ₂ ) inclined second Befestigungselementenabstützfläche (50), wherein a second fastening element (54) by means of at least one with respect to the cylinder head (14) is supported or supportable second Fastening bolt unit (56) against the cylinder head (14) is pressed or pressed and with respect to the second bearing surface (22) with the second wedge angle (W ₂ ) inclined second Befestigungsflanschabstützfläche (66) identifies. Fastening arrangement according to claim 6, characterized in that a second fastening bolt longitudinal axis (A ₂ ) of the at least one second fastening bolt unit (56) with respect to the second contact surface (22) with a second longitudinal axis angle (L ₂ ) is arranged, wherein the second longitudinal axis angle (L ₂ ) in the range of 90 °. Fastening arrangement according to claim 6 or 7, characterized in that the second wedge angle (W ₂ ) is greater than the first wedge angle (W ₁ ). Fastening arrangement according to one of claims 6-8, characterized in that the second fastening element (54) to the second fastening bolt longitudinal axis (A ₂ ) of the at least one second fastening bolt unit (56) substantially orthogonal second Befestigungsbolzeneinheitabstützfläche (60) for supporting the at least one second fastening bolt unit (56) with respect to the second fastener (54). Fastening arrangement according to one of claims 1-9, characterized in that the outlet manifold (12) made of steel, preferably ST52, is constructed, or / and that the first fastening element (38) made of steel, preferably ST52, constructed, and / or the static friction coefficient (μ) is in the range of 0.10 to 0.14, preferably in the range of 0.11 to 0.13. Internal combustion engine, in particular for a motor vehicle, comprising a cylinder head (14) fixed to a cylinder block and an exhaust manifold (12) fixed to the cylinder head (14) by means of a fastening arrangement (10).

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