Internal combustion engine for a motor vehicle, and motor vehicle

Abstract

The invention relates to an internal combustion engine (10) for a motor vehicle, having a crankcase (12) and having a cylinder head (14) which is formed separately from the crankcase (12) and is connected to the crankcase (12), wherein the crankcase (12) and the cylinder head (14) are adhesively bonded directly to one another by means of an adhesive (K) arranged between the crankcase (12) and the cylinder head (14).

Description

[0001] Mercedes-Benz Group AG

[0002] internal combustion engine for a motor vehicle as well as motor vehicle

[0003] The invention relates to an internal combustion engine for a motor vehicle, in particular for a car, according to the preamble of claim 1 or 8. Furthermore, the invention relates to a motor vehicle, in particular a car, with such an internal combustion engine.

[0004] US Patent 5,961,127 A discloses a sealing structure for a cylinder and a cylinder head in an internal combustion engine designed as a reciprocating piston engine. Furthermore, German Patent DE 10,2011 008,988 A1 discloses an internal combustion engine for a motor vehicle.

[0005] The object of the present invention is to create an internal combustion engine for a motor vehicle and a motor vehicle with such an internal combustion engine, so that a particularly high robustness of the internal combustion engine can be achieved.

[0006] This problem is solved by an internal combustion engine with the features of claim 1, by an internal combustion engine with the features of claim 9, and by a motor vehicle with the features of claim 11. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0007] A first aspect of the invention relates to an internal combustion engine, also referred to as a combustion engine, internal combustion power unit, or motor, for a motor vehicle, also referred to simply as a vehicle. This means that the motor vehicle, preferably designed as a motor vehicle, in particular as a passenger car, in its fully manufactured state, has the internal combustion engine and can be driven by means of the internal combustion engine. The internal combustion engine is designed as a reciprocating engine, and thus as a reciprocating piston engine, and has a crankcase, also designed as a cylinder housing or cylinder block.

[0008] The internal combustion engine also has a cylinder head. The cylinder head is separate from the crankcase and connected to it. For this purpose, separate screws can be provided, for example, to connect the cylinder head to the crankcase, thus connecting the cylinder head to the crankcase and vice versa. In particular, each screw has a first thread, especially an external thread, which is screwed directly into a corresponding second thread, especially an internal thread, such that the first thread is screwed directly into the second thread. The second thread is provided as an internal thread in the crankcase.This means that the crankcase and cylinder head are bolted together and thus connected, i.e., fastened to each other. The respective second thread is formed by a corresponding screw element that corresponds to the respective screw.

[0009] The internal combustion engine, for example, has at least one combustion chamber in which combustion processes take place during operation. The combustion chamber is partially bounded by a cylinder, partially by a combustion chamber roof, and partially by a piston that is movably mounted within the cylinder. The cylinder is a cylinder of the crankcase. Thus, the crankcase contains the cylinder, so the crankcase forms the cylinder. The combustion chamber roof is formed by the cylinder head. During the respective combustion process, a mixture, also known as a fuel-air mixture, is burned in the combustion chamber, in particular ignited and combusted. The mixture comprises at least air and a fuel, in particular a liquid fuel.For example, the internal combustion engine is designed as a spark-ignited internal combustion engine, in particular as a gasoline engine, or as a self-igniting internal combustion engine, in particular as a diesel engine.

[0010] The internal combustion engine, for example, has a crankshaft designed as an output shaft, which is rotatable around a crankshaft axis relative to the crankcase. The piston is articulated to the crankshaft via a connecting rod, so that the translational movements of the piston within the cylinder and relative to the crankcase can be converted into a rotational movement of the crankshaft. During this rotational movement, the crankshaft rotates around its axis relative to both the crankcase and the cylinder head. In particular, the internal combustion engine can provide drive torque via the crankshaft to propel the vehicle.

[0011] To achieve particularly high robustness of the internal combustion engine, the first aspect of the invention provides that the crankcase and the cylinder head are directly bonded together by means of an adhesive arranged between the crankcase and the cylinder head. This means that the crankcase has a first bonding surface and the cylinder head a second bonding surface. The bonding surfaces face each other. In particular, each bonding surface lies in a plane, with the planes being parallel to or coinciding with each other. Thus, the bonding surfaces, and therefore the crankcase and the cylinder head, are directly bonded together by means of the adhesive and thus materially connected.In contrast to conventional solutions, the invention eliminates the need for a cylinder head gasket located between the crankcase and the cylinder head and designed separately from the crankcase and the cylinder head, by which the crankcase and the cylinder head are supported against each other in 14 conventional solutions.

[0012] It is preferably provided that no sealing element, in addition to the adhesive and in addition to the crankcase and the cylinder head, is arranged between the crankcase and the cylinder head to seal them against each other. The adhesive directly contacts the bonding surfaces without a sealing element, separate from the crankcase and the cylinder head, being arranged between the bonding surfaces, so that, apart from the adhesive, no other sealing element, in addition to the adhesive, the crankcase and the cylinder head, is arranged between the bonding surfaces and thus between the crankcase and the cylinder head.The adhesive surfaces are or function, for example, as support surfaces which are directly or indirectly supported against each other by means of the adhesive, without a sealing element being arranged between the adhesive surfaces in addition to the adhesive and in addition to the crankcase and the cylinder head, and which is designed separately from the crankcase and the cylinder head, so that the crankcase and the cylinder head are directly or, in particular, only indirectly supported against each other by means of the adhesive.

[0013] In particular, it is preferably provided that exactly one adhesive layer formed by the adhesive is arranged between the crankcase and the cylinder head, especially between the bonding surfaces, by means of which the crankcase and the cylinder head, especially the bonding surfaces and thus the crankcase and the cylinder head, are directly bonded to one another and thereby connected to each other. In particular, the adhesive layer directly contacts the bonding surfaces without a sealing element being arranged between the bonding surfaces and thus between the crankcase and the cylinder head, in addition to the crankcase and the cylinder head and in addition to the adhesive layer, and which is formed separately from the crankcase and the cylinder head.

[0014] The invention is based in particular on the following findings and considerations: It has been found that in highly stressed internal combustion engines, which are operated under high load, i.e., high cylinder pressure and high combustion temperature, and / or frequently undergo cold starts followed by strong or high acceleration, resulting in high temperature and pressure fluctuations in the cylinders, relatively large relative movements occur between the crankcase and the conventionally provided cylinder head gasket and / or between the cylinder head and the conventionally provided cylinder head gasket and / or between the crankcase and the cylinder head. These relative movements can cause deformations of a base material, particularly of the cylinder head, at a contact surface of the crankcase and / or the cylinder head where the conventionally provided cylinder head gasket rests directly on or against it.This can lead to gas leaks and, due to superimposed stress and notch effects, to cracks, especially in the crankcase, if no 2024P01445WQ.

[0015] 5. Appropriate countermeasures have been taken. This means that the aforementioned relative movements can lead to cracking, in particular cracking due to frictional wear in the cylinder's edge region. Specifically, the deformation of the cylinder head is transmitted to the crankcase via the cylinder head gasket in the area of ​​a so-called stop ring of the cylinder head gasket, resulting in the aforementioned cracking in the area of ​​the stop ring at the cylinder's edge. The stop ring of the cylinder head gasket, which is a known feature, lies in the cylinder's edge region, enclosing the cylinder between the crankcase and the cylinder head, and provides additional sealing for the combustion chamber.

[0016] To avoid the aforementioned disadvantages, the invention provides that, compared to conventional solutions, the cylinder head gasket is omitted as a sealing element between the crankcase and the cylinder head, and the crankcase and the cylinder head are bonded directly to each other using the adhesive. In other words, the cylinder head is bonded directly to the crankcase without a cylinder head gasket or any other sealing element, in addition to the adhesive and in addition to the crankcase and the cylinder head, being arranged between them. Thus, an adhesive bond is created between the crankcase and the cylinder head, which are directly bonded together by means of this adhesive connection.In addition to the adhesive bond, screws designed, for example, as cylinder head bolts can be used to create a screw connection between the crankcase and the cylinder head, which are then bolted together and thus connected. The invention is also based on the understanding that the adhesive bond, also referred to as a bonded connection, is sufficient on its own to hold the cylinder head and crankcase together gas-tight and with sufficient strength. Advantageously, the invention now makes it possible, on the one hand, to dispense with conventionally used high-quality, high-tensile-strength cylinder head bolts and, on the other hand, to use cylinder head bolts of lower quality and / or lower tensile strength only for the additional securing of the adhesive bond, so that the cylinder head bolts can be, for example, smaller, i.e.,Cylinder head bolts can be smaller in diameter and / or have lower tensile strength and / or fewer in number than conventional bolts when using a cylinder head gasket, thus saving costs and assembly effort. Furthermore, it offers the possibility of designing cylinder heads more efficiently or rethinking conventional designs, since using an adhesive bond instead of a cylinder head gasket reduces the tensile stresses the cylinder head has to absorb from the bolts, and / or smaller cylinder head bolts with, for example, a smaller diameter allow more clearance for cooling channels and / or exhaust and / or intake ports in the cylinder head.As a result, the previously described relative movements between the crankcase and the cylinder head can be absorbed by the at least partially elastic adhesive bond, thereby avoiding undesirable effects resulting from such relative movements, such as the previously described cracking and gas leaks.It was found that, due to a force component of the adhesive and because of a high combustion pressure of, for example, 200 bar occurring in the combustion chamber during the fired operation of the internal combustion engine, the expansion of the cylinder, especially in its upper region, can be advantageously kept low when using cylinder head bolts, thereby avoiding excessive relative movements between the crankcase and the cylinder head and the resulting undesirable effects. High specific power outputs of the internal combustion engine can thus be achieved without the aforementioned undesirable effects.

[0017] In order to be able to connect the crankcase and the cylinder head particularly firmly and gas-tightly without a cylinder head gasket or another sealing element, provided separately from the crankcase and the cylinder head and designed to seal the crankcase and the cylinder head against each other, being arranged between the crankcase and the cylinder head in addition to the adhesive and in addition to the crankcase and the cylinder head, it is provided in one embodiment of the invention that the adhesive is an anaerobic adhesive.

[0018] In a preferred alternative embodiment, the adhesive is a silicone. Preferably, a heat-resistant silicone is used. Silicone can be used both as a sealant and as an adhesive. Silicones are characterized by high elasticity, high heat resistance, and the ability to compensate for movement between components. Silicones also possess adhesive properties and can be used, among other things, for flexible bonding, particularly where elasticity and temperature resistance are required.

[0019] Another embodiment is characterized by the fact that the adhesive has a temperature resistance of at least 210 degrees Celsius. This means that the adhesive can withstand temperatures of up to 210 degrees Celsius and thus firmly bond the crankcase and the cylinder head together up to a temperature of 210 degrees Celsius, thereby ensuring a particularly high robustness of the internal combustion engine.

[0020] To advantageously reduce undesirable relative movements between the crankcase and the cylinder head, and thus achieve particularly high robustness of the internal combustion engine, a further embodiment of the invention provides that the internal combustion engine has dowel pins formed separately from the crankcase and the cylinder head, as well as dowel pins formed separately from the adhesive, wherein each dowel pin is designed as a solid and inherently rigid body. Each dowel pin engages in a corresponding first recess in the crankcase and a corresponding second recess in the cylinder head. In particular, the crankcase and the cylinder head are positioned relative to each other by means of the dowel pins.

[0021] It is conceivable that each dowel pin engages with its respective first recess in the crankcase, thus forming a first fit with its respective first recess. Alternatively or additionally, it is possible that each dowel pin engages with its respective second recess in the cylinder head, thus forming a second fit with its respective second recess.

[0022] In order to avoid excessive relative movements between the crankcase and the cylinder head and thus achieve a particularly high robustness of the internal combustion engine, it is further provided in the invention that the respective first fit and / or the respective second fit is a respective transition fit, so that preferably the dowel pins engage with a respective transition fit in the recesses of the cylinder head and / or in the recesses of the crankcase.

[0023] In order to achieve a particularly high robustness of the internal combustion engine in a particularly cost-effective manner, a further embodiment of the invention provides that the respective first fit and / or the respective second fit is a clearance fit, so that the dowel pins engage with a clearance fit in the recesses of the cylinder head and / or in the recesses of the crankcase.

[0024] To particularly advantageously prevent undesired relative movements between the crankcase and the cylinder head, and consequently to achieve a particularly high robustness of the internal combustion engine, a further embodiment of the invention provides that the adhesive is contained in the recesses of the cylinder head and / or in the recesses of the crankcase, thus acting as a filler. This prevents excessive relative movements between the respective dowel pin and the crankcase or the cylinder head. Furthermore, the respective dowel pin can, for example, be bonded to the crankcase or the cylinder head using the adhesive, so that excessive, undesired relative movements between the crankcase and the cylinder head can be reliably prevented.

[0025] The respective first recess and / or the respective second recess is, for example, designed as a bore and thus produced by machining. In particular, it is conceivable that the respective dowel pin is held in the respective recess by means of the adhesive, thereby advantageously preventing undesired relative movements.

[0026] A second aspect of the invention relates to an internal combustion engine, also referred to as a combustion engine, internal combustion power plant, or motor, for a motor vehicle, also referred to simply as a vehicle. Advantages and advantageous embodiments of the first aspect of the invention are to be considered as advantages and advantageous embodiments of the second aspect of the invention, and vice versa. Thus, the preceding and following embodiments of the first aspect of the invention can readily be transferred to the second aspect of the invention, and vice versa. The internal combustion engine according to the second aspect of the invention has a crankcase. The internal combustion engine according to the second aspect of the invention has a cylinder head. The cylinder head is formed separately from the crankcase and connected to the crankcase.

[0027] To achieve particularly high robustness of the internal combustion engine, the second aspect of the invention provides for an intermediate element, separate from the crankcase and cylinder head, to be arranged between them. This intermediate element supports the crankcase and cylinder head against each other. Specifically, in this second aspect of the invention, the crankcase has a first bonding surface and the cylinder head has a second bonding surface. The bonding surfaces face each other, with the intermediate element positioned between them. Thus, the bonding surfaces face the intermediate element. In particular, each bonding surface extends in a specific plane, with the planes being parallel to or coinciding with each other.

[0028] The intermediate element is bonded to the cylinder head, in particular to the second adhesive surface of the cylinder head, by means of a first adhesive layer arranged between the intermediate element and the cylinder head, in particular between the intermediate element and the second adhesive surface, directly to the second adhesive layer, and thus directly to the cylinder head. The intermediate element is bonded to the crankcase, in particular to the first adhesive surface of the crankcase, by means of a second adhesive layer arranged between the intermediate element and the crankcase, in particular between the intermediate element and the first adhesive surface of the crankcase, directly to the crankcase, in particular directly to the first adhesive surface, and thus to the crankcase.The characteristic that the intermediate element is bonded directly to the crankcase and the cylinder head, i.e., directly to the respective bonding surface of the crankcase and the cylinder head, means that, with the exception of the respective adhesive layer, also referred to as the respective adhesive layer, between the intermediate element and the respective bonding surface, and thus between the intermediate element and the crankcase and the cylinder head, no other, further, 2024P01445WÖ.

[0029] 10. In addition to the adhesive, the intermediate element, and the crankcase and cylinder head, a sealing element of the internal combustion engine is provided and is designed separately from the intermediate elements and separately from the crankcase and cylinder head. The background of the second aspect of the invention is, in particular, the realization that an adhesive arranged between the crankcase and the cylinder head, especially between the bonding surfaces, by means of which the crankcase and the cylinder head, especially the bonding surfaces, can be directly bonded to one another, must accommodate a residual relative movement between the crankcase and the cylinder head, even if very small, but technically unavoidable. For this purpose, the adhesive must have advantageous elasticity.If the adhesive, considered in isolation, does not exhibit sufficient elasticity to accommodate even very slight relative movements between the cylinder head and the crankcase, then the intermediate element is preferably used, which allows the formation of the aforementioned two adhesive layers. Compared to a single adhesive layer positioned between the crankcase and the cylinder head, the use of two adhesive layers achieves twice the elasticity when using an identical adhesive for both layers. This allows relative movements between the crankcase and the cylinder head to be advantageously accommodated, while the crankcase and cylinder head remain firmly and gas-tightly bonded to each other.

[0030] Preferably, the intermediate element is a dummy, also known as a dummy, which, for example, has an outline and / or shape like a conventional cylinder head gasket. This allows, for example, the continued use of openings in the crankcase and cylinder head that are used for coolant transfer between the crankcase and the cylinder head. The openings in the crankcase and cylinder head are generally undesirably large because, for casting reasons, they cannot be produced with advantageously small cross-sections, especially when the crankcase and cylinder head are formed as a single casting and thus manufactured from it. When using the intermediate element, it is possible to design the intermediate element with additional openings configured as through-holes, which overlap with the openings of the crankcase and the 2024P01445WÖ

[0031] 11

[0032] The openings of the intermediate element are arranged so that the coolant can flow through them between the crankcase and the cylinder head. These additional openings can advantageously be manufactured with small cross-sections, allowing them to act as a throttling mechanism for the coolant exchange between the crankcase and the cylinder head, i.e., for the coolant flow between the crankcase and the cylinder head. In particular, the flow cross-section of each additional opening through which the coolant flows is smaller than the flow cross-sections of the openings with which it overlaps.This allows the coolant flow between the crankcase and the cylinder head to be advantageously throttled or the coolant flow to be adjusted, and the crankcase and cylinder head can be manufactured advantageously.

[0033] In order to achieve a particularly high robustness of the internal combustion engine, in one embodiment of the second aspect of the invention it is provided that the intermediate element is made of a metallic material, in particular sheet metal.

[0034] A third aspect of the invention relates to a motor vehicle, also simply referred to as a vehicle, preferably designed as a motor car, in particular as a passenger car, which has an internal combustion engine according to the first aspect of the invention or according to the second aspect of the invention and can be driven by means of the internal combustion engine. Advantages and advantageous embodiments of the first aspect and the second aspect of the invention are to be regarded as advantages and advantageous embodiments of the third aspect of the invention and vice versa.

[0035] Further advantages, features, and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing. The features and combinations of features mentioned above in the description, as well as those mentioned below in the figure description and / or shown in the figures alone, are not only present in the combinations specified, but also in other configurations.

[0036] 12

[0037] Can be used in combinations or on their own without leaving the scope of the invention.

[0038] The drawing shows in:

[0039] Fig. 1 shows a partial schematic sectional view of a first embodiment of an internal combustion engine for a motor vehicle;

[0040] Fig. 2 shows a partial schematic underside view of a cylinder head of the internal combustion engine according to the first embodiment;

[0041] Fig. 3 shows a partial schematic sectional view of the internal combustion engine according to the first embodiment;

[0042] Fig. 4 shows a further schematic underside view of the cylinder head of the internal combustion engine according to the first embodiment;

[0043] Fig. 5 shows a schematic cross-sectional view of a dowel pin of the internal combustion engine according to the first embodiment; and

[0044] Fig. 6 shows a schematic top view of an intermediate element of a second embodiment of the internal combustion engine.

[0045] In the figures, identical or functionally equivalent elements are provided with the same reference symbols.

[0046] Fig. 1 shows a partial schematic sectional view of a first embodiment of an internal combustion engine 10 of a motor vehicle, designed as a reciprocating piston engine. The internal combustion engine 10 has a crankcase 12. The internal combustion engine 10 also has a cylinder head 14.

[0047] The internal combustion engine 10 has combustion chambers, two of which are partially visible in Fig. 3 and are labelled 16. Each combustion chamber 16 is partially formed, i.e., delimited, by a respective cylinder 18, a respective combustion chamber roof 20, and a respective piston that is movably mounted within the respective cylinder 18. The cylinders 18 are cylinders of the crankcase 12 and are thus formed by the crankcase 12. In other words, the crankcase 12 contains the cylinders 18. The combustion chamber roofs 20 are formed by the cylinder head 14, and are therefore combustion chamber roofs of the cylinder head 14.

[0048] For example, the crankcase 12 is designed as a first casting and is therefore manufactured by casting. Alternatively or additionally, the cylinder head 14 is a second casting and is therefore manufactured by casting. For example, the crankcase 12 is designed as a single piece, that is, formed from a single part. Preferably, the cylinder head 14 is designed as a single piece, that is, formed from a single part.

[0049] Fig. 2 shows a partial schematic bottom view of the cylinder head 14. It can be seen from Fig. 2 that each combustion chamber 16 is assigned, in particular, exactly four gas exchange valves. Of these, in particular, two of the gas exchange valves assigned to each combustion chamber 16 are inlet valves designated 22, and, in particular, exactly two of the four gas exchange valves assigned to each combustion chamber 16 are exhaust valves designated 24.

[0050] As can be seen from Fig. 3, the combustion chambers 16, and thus the cylinders 18, are arranged successively in a row along a straight direction of arrangement, illustrated by a double arrow 26, i.e., along a straight line. In particular, a respective web 28 of the crankcase 12 is arranged between each pair of cylinders 18 that are adjacent to each other along this direction. The respective cylinders 18, which are arranged directly adjacent to each other along this direction, are separated from each other by the respective web 28 arranged between them.

[0051] The gas exchange valves are held on the cylinder head 14 so as to be movable, particularly translationally.

[0052] For example, each combustion chamber 16 is assigned a respective injector by means of which a fuel, in particular liquid, can be introduced, in particular injected, into the respective assigned combustion chamber 16, in particular directly. The respective injector is arranged at least partially in a respective, corresponding receptacle of the cylinder head 14, one of which is visible in Fig. 3 and is designated 30.

[0053] Figures 1 to 5 show a first embodiment of the internal combustion engine.

[0054] In the first embodiment, the separately formed crankcase 12 and cylinder head 14 are connected to each other such that the crankcase 12 and the cylinder head 14 are directly bonded to each other by means of an adhesive K arranged between the crankcase 12 and the cylinder head 14, and are thus materially bonded to each other, without a sealing element being arranged between the crankcase 12 and the cylinder head 14, in addition to the adhesive K and in addition to the crankcase 12 and the cylinder head 14, and which is formed separately from the crankcase 12 and the cylinder head 14 and separately from the adhesive K. The crankcase 12 has a first bonding surface F1, and the cylinder head 14 has a second bonding surface F2. The bonding surfaces F1 and F2 face each other.The respective bonding surfaces F1 and F2 lie in their respective planes. These planes are parallel to each other or coincide. The adhesive K is positioned between the bonding surfaces F1 and F2 and directly contacts them, without a sealing element being arranged between the bonding elements F1 and F2. This sealing element would be a solid body, separate from the adhesive K and the crankcase 12 and cylinder head 14, and would seal the crankcase 12 and cylinder head 14 against each other. As a result, the bonding surfaces F1 and F2 are directly bonded to each other, thus directly bonding the crankcase 12 and cylinder head 14 together and creating a material-bonded connection.It is also evident that between the adhesive surfaces F1 and F2 exactly one adhesive layer S, also referred to as an adhesive layer, is arranged, formed by the adhesive K, which directly touches the adhesive surfaces F1 and F2 and thereby bonds them directly together, without a sealing element being arranged between the adhesive surfaces F1 and F2 in addition to the adhesive K and in addition to the crankcase 12 and the cylinder head 14, which is formed separately from the crankcase 12 and the cylinder head 14 and separately from the adhesive K, is formed as a solid body and seals the crankcase 12 and the cylinder head 14 against each other.In the first embodiment, no additional, solid-body component of the internal combustion engine 10 is arranged between the adhesive surfaces F1 and F2, in addition to the adhesive K and in addition to the crankcase 12 and the cylinder head 14.

[0055] Preferably, the adhesive K is an anaerobic adhesive. Particularly preferably, the adhesive K is a silicone. Preferably, the adhesive K has a temperature resistance of at least 210 degrees Celsius. In principle, all temperature-resistant and sealing adhesives with sufficient elasticity are conceivable. It is also conceivable that the adhesive K is made of a plastic. Furthermore, it is conceivable that the adhesive K is made of a metallic material, and thus, for example, of a liquid metal.

[0056] To ensure a particularly strong and gas-tight connection between the crankcase 12 and the cylinder head 14, especially over a long service life of the internal combustion engine 10, the internal combustion engine 10, according to the first embodiment, has screws 32 that are designed separately from the crankcase 12 and the cylinder head 14 and separately from the adhesive K. These screws are provided in addition to the crankcase 12 and the cylinder head 14 and in addition to the adhesive K and are designed, for example, as cylinder head bolts, in particular as expansion bolts. The crankcase 12 and the cylinder head 14 are screwed together and thus connected by means of the screws 32. In the first embodiment, each screw 32 has a first thread designed as an external thread.In the first embodiment, each screw 32 is associated with a corresponding internal thread (not shown) as a second thread in the crankcase 12. The first thread of each screw 32 is screwed, in particular directly, into the second thread of the screw element associated with each screw 32, thereby screwing the crankcase 12 and the cylinder head 14 together. It can be seen that each screw 32 penetrates the adhesive K and thus the adhesive layer S. Furthermore, each screw 32 penetrates a corresponding first through-opening 34 of the cylinder head 14. 2024P01445WÖ.

[0057] Each screw 32 engages in a corresponding opening 36 of the cylinder head 14. For example, the respective opening 36 is a second through-hole which is penetrated by the respective screw 32 engaging in the respective opening 36.

[0058] To detach the bonded cylinder head 14 from the crankcase 12, and thus to separate the bonded crankcase 12 and cylinder head 14, various methods are conceivable. In one method, for example, a local heating, particularly overheating, of the adhesive K is caused by means of an energy beam, in particular a laser beam, thereby negatively impairing, and in particular destroying, the adhesive K, at least with regard to its ability to bond the crankcase 12 and the cylinder head 14 together. Alternatively or additionally, such local heating or overheating of the adhesive K can be caused by means of an oven in which the crankcase 12 and the cylinder head 14 are placed.The described heating, in particular overheating, of the adhesive K by means of the energy beam and / or by means of the oven can negatively impair, i.e., destroy, the adhesive K, at least with regard to its ability or function to bond the crankcase 12 and the cylinder head 14 together, so that, as a result of the heating, in particular overheating, of the adhesive K, the crankcase 12 and the cylinder head 14 can be separated from each other, in particular without causing undesirable damage to the crankcase 12 and the cylinder head 14. In a second possibility, heating wires, in particular made of a metallic material, are arranged in the adhesive layer S and thus in the adhesive K, which are supplied with electrical energy and thereby electrically heated.This causes the adhesive K to heat up, in particular to overheat, thereby negatively impairing, in particular destroying, the adhesive K, at least with regard to its function or ability to bond the crankcase 12 and the cylinder head 14 together, so that, as a result of the heating, in particular overheating, of the adhesive K, the crankcase 12 and the cylinder head 14 can be separated from each other, in particular non-destructively, i.e., in such a way that no damage or destruction of the crankcase 12 and the cylinder head 14 occurs. In a third possibility, a solvent is used by means of which the adhesive K is at least partially dissolved and thereby negatively impaired, i.e., destroyed, at least with regard to its ability to bond the crankcase 12 and the cylinder head 14 together.In a fourth method, pressure screws are used which are rotated relative to the crankcase 12 and the cylinder head 14, thereby causing the bonding surfaces F1 and F2 to move away from each other. In a fifth method, a wedge is used by means of which the bonding surfaces F1 and F2 are moved away from each other, in particular by driving the wedge between the bonding surfaces F1 and F2. In a sixth method, a spreading wedge, in particular a hydraulic spreading wedge, is used by means of which the bonding surfaces F1 and F2 are moved away from each other, in particular by placing the spreading wedge at a suitable point between the bonding surfaces F1 and F2.

[0059] Preferably, a heat-resistant adhesive is used as adhesive K. Adhesive K can be a one-component adhesive. Furthermore, it is conceivable that adhesive K is a two-component or a multi-component adhesive. Silicone is particularly preferred as adhesive K. In the process for manufacturing the internal combustion engine 10, for example, the adhesive K, in a liquid, and in particular a paste-like, state, is applied to the bonding surface F1 and / or the bonding surface F2, whereupon the bonding surfaces F1 and F2 are bonded together by means of the adhesive K, in particular directly. In particular, the adhesive can be applied with a roller or brush, sprayed on, or laid down as a matrix.

[0060] The adhesive K creates a bonded connection, also known as an adhesive bond or adhesive joint, by which the crankcase 12 and the cylinder head 14 are directly bonded together and thus connected. The optionally provided screws 32 create a screwed connection by which the crankcase 12 and the cylinder head 14 are bolted together and thus connected. The screwed connection is optional and can be provided in addition to the adhesive connection.

[0061] A dowel pin connection between the crankcase 12 and the cylinder head 14 can optionally be provided. This dowel pin connection is optional and is explained in more detail below. The dowel pin connection can be provided in addition to the adhesive connection and preferably in addition to the screw connection. The dowel pin connection is formed by dowel pins of the internal combustion engine 10, one of which is visible in Fig. 3 and is designated 38. This means that the dowel pins 38 form, i.e., create, the dowel pin connection. The dowel pins 38 are separate from the crankcase 12 and the cylinder head 14, and separate from each other. They are provided in addition to the crankcase 12 and the cylinder head 14, and also in addition to the adhesive K. If the screw connection is provided, the dowel pins 38 are provided in addition to the screws 32 and are designed separately from them.

[0062] As can be seen from Fig. 3, the respective dowel pin 38 engages in a respective, corresponding first recess 40 of the crankcase 12 and in a respective, corresponding second recess 42 of the cylinder head 14.

[0063] As can be seen from Fig. 4, the combustion chamber roofs 20, as well as the combustion chambers 16 and the cylinders 18, are arranged successively along the direction of arrangement illustrated by the double arrow 26, and thus in a series, with a further web 44 of the cylinder head 14 being arranged between two combustion chamber roofs 20 that are directly adjacent to each other along this direction. It can be seen from Fig. 4, for example, that two recesses 40, 42 are formed in the respective web 44 and thus correspondingly in the respective web 28 of the crankcase 12, in particular, into which one of the dowel pins 38 engages. For example, the respective recess 40, 42 is formed as a bore produced by machining.

[0064] The respective dowel pin 38 can, for example, engage with the respective recess 40 with a specific fit. The specific fit could be, for example, a transition fit such as h6 / N6. It is conceivable that the respective dowel pin 38 engages with the respective recess 42 without a specifically manufactured fit. Conversely, it is conceivable that the respective dowel pin 38 engages with the respective recess 42 with a specific fit, such as a transition fit, and engages with the respective recess 40 without a specifically manufactured fit. For example, in this case, the recess 42 has an interference of, for example, 200 pm relative to the dowel pin 38 engaging in the recess 42. Thus, the dowel pin 38 engages with play in the respective recess 42. In this case, it is provided that the adhesive K is applied to the respective recess 42.

[0065] 19 is arranged and is therefore a filler or functions as a filler. In particular, the adhesive K is a curing adhesive which is applied in liquid state to the bonding surface F1 and / or the bonding surface F2, whereupon the bonding surfaces F1 and F2 are bonded together by means of the adhesive K and the adhesive K cures.

[0066] It is also conceivable that the adhesive K is made of a plastic. Furthermore, it is conceivable that the adhesive K is made of a metallic material, and thus, for example, of a liquid metal.

[0067] The dowel pins 38 engage in respective recesses 40 of the crankcase 12 and the cylinder head 14, thereby preventing or greatly reducing relative movements between the crankcase 12 and the cylinder head 14.

[0068] Fig. 5 shows a schematic cross-sectional view of one of the dowel pins 38. Also shown in Fig. 5 is the adhesive K, which is included as a filler in the recess 42 into which the dowel pin 38 engages, in particular with clearance.

[0069] Finally, a second embodiment of the internal combustion engine 10 is illustrated with reference to Fig. 6. In the second embodiment, an intermediate element 46, designed separately from the crankcase 12 and the cylinder head 14, is arranged between the crankcase 12 and the cylinder head 14, and the crankcase 12 and the cylinder head 14 are supported against each other by means of this intermediate element. The rigid intermediate element 46, designed as a solid body, is bonded directly to the adhesive surface F1 and thus directly to the cylinder head 14 by means of a first adhesive layer arranged between the intermediate element 46 and the adhesive surface F2, and thus between the intermediate element 46 and the cylinder head 14.The intermediate element 46 is bonded to the crankcase 12 by means of a second adhesive layer arranged between the intermediate element 46 and the adhesive surface F1, and thus directly to the crankcase 12. For this purpose, the intermediate element 46 has two further adhesive surfaces: a third adhesive surface F3 and a fourth adhesive surface (not visible in Fig. 6) located opposite the third adhesive surface F3. Adhesive surface F3 faces away from the fourth adhesive surface, and vice versa. The third adhesive surface F3 faces towards the adhesive surface F2, and vice versa, so that the third adhesive surface F3 faces away from the first adhesive surface F1. The fourth adhesive surface faces towards the first adhesive surface F1, and vice versa, with the fourth adhesive surface facing away from both the third adhesive surface F3 and the second adhesive surface F2.The first adhesive layer is arranged between the third adhesive surface F3 and the second adhesive surface F2 and directly contacts the adhesive surfaces F2 and F3, thereby bonding the adhesive surfaces F2 and F3 directly to each other, without a sealing element being arranged between the adhesive surfaces F2 and F3 in addition to the adhesive layers and in addition to the crankcase 12 and the cylinder head 14 and in addition to the intermediate element 46, and which is formed separately from the crankcase 12 and the cylinder head 14 and separately from the adhesive layers and separately from the intermediate element 46, sealing the cylinder head 14 against the intermediate element 46.

[0070] It is conceivable that the adhesive layers are formed from the same adhesive. Furthermore, it is conceivable that the first adhesive layer is formed from a first adhesive and the second adhesive layer from a second adhesive. The first and second adhesives can be the same adhesive, or the first adhesive can be a different adhesive.

[0071] The second adhesive layer is arranged between the adhesive surface F1 and the fourth adhesive surface and directly contacts the fourth adhesive surface and the first adhesive surface F1, thereby bonding the first adhesive surface F1 and the fourth adhesive surface directly to each other, without the need for a sealing element between the adhesive surface F1 and the fourth adhesive surface, in addition to the crankcase 12 and the cylinder head 14, the intermediate element 46, and the adhesive layers. This sealing element would be separate from the crankcase 12 and the cylinder head 14, separate from the adhesive layers, and separate from the intermediate element 46, and would seal the crankcase 12 against the intermediate element 46. 2024P01445WÖ

[0072] 21

[0073] Reference symbol list

[0074] 10 Internal combustion engine

[0075] 12 cylinder housings

[0076] 14 Cylinder head

[0077] 16 combustion chamber

[0078] 18 cylinders

[0079] 20 Combustion chamber roof

[0080] 22 inlet valves

[0081] 24 exhaust valves

[0082] 26 Double Arrow

[0083] 28 Bridge

[0084] 30 recordings

[0085] 32 screw

[0086] 34 Passage opening

[0087] 36 Opening

[0088] 38 Dowel pin

[0089] 40 Exclusion

[0090] 42 Exclusion

[0091] 44 Bridge

[0092] 46 Intermediate element

[0093] F1 first adhesive surface

[0094] F2 second adhesive surface

[0095] F3 third adhesive surface

[0096] K adhesive

[0097] S adhesive layer

Claims

Mercedes-Benz Group AG Patent claims 1. Internal combustion engine (10) for a motor vehicle, comprising a crankcase (12) and a cylinder head (14) which is formed separately from the crankcase (12) and connected to the crankcase (12), characterized in that the crankcase (12) and the cylinder head (14) are bonded directly to each other by means of an adhesive (K) arranged between the crankcase (12) and the cylinder head (14).

2. Internal combustion engine (10) according to claim 1, characterized in that no sealing element is arranged between the crankcase (12) and the cylinder head (14) in addition to the adhesive (K) and in addition to the crankcase (12) and the cylinder head (14) sealing the crankcase (12) and the cylinder head (14) against each other.

3. Internal combustion engine (10) according to claim 1 or 2, characterized in that the adhesive (K) is an anaerobic adhesive.

4. Internal combustion engine (10) according to claim 1 or 2, characterized in that the adhesive (K) is a silicone.

5. Internal combustion engine (10) according to one of the preceding claims, characterized in that the adhesive (K) has a temperature resistance of at least 210 degrees Celsius.

6. Internal combustion engine (10) according to one of the preceding claims, characterized in that dowel pins (38) are provided which are formed separately from the crankcase (12) and the cylinder head (14) and engage in respective recesses (40, 42) of the crankcase (12) and the cylinder head (14).

7. Internal combustion engine (10) according to claim 6, characterized in that the dowel pins (38) engage with a respective transition fit in the recesses (42) of the cylinder head (14) and / or in the recesses (40) of the crankcase (12).

8. Internal combustion engine (10) according to claim 6, characterized in that the dowel pins (38) engage with a respective clearance fit in the recesses (42) of the cylinder head (14) and / or in the recesses (40) of the crankcase (12).

9. Internal combustion engine (10) according to one of claims 6 to 8, characterized in that the adhesive (K) is incorporated as a filler in the recesses (42) of the cylinder head (14) and / or in the recesses (40) of the crankcase (12).

10. Internal combustion engine (10) for a motor vehicle, with a crankcase (12) and with a cylinder head (14) which is formed separately from the crankcase (12) and connected to the crankcase (12), characterized in that: - an intermediate element (46) is arranged between the crankcase (12) and the cylinder head (14), which is designed separately from the crankcase (12) and the cylinder head (14), and by means of which the crankcase (12) and the cylinder head (14) are supported against each other; - the intermediate element (46) is bonded directly to the cylinder head (14) by means of a first adhesive layer arranged between the intermediate element (46) and the cylinder head (14); and - the intermediate element (46) is bonded directly to the crankcase (12) by means of a second adhesive layer arranged between the intermediate element (46) and the crankcase (12).

11. Internal combustion engine (10) according to claim 10, characterized in that the intermediate element (46) is made of a metallic material.

12. Motor vehicle, comprising an internal combustion engine (10) according to any of the preceding claims.

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