Bearing arrangement for a camshaft of an internal combustion engine and crankcase with same

Abstract

A bearing arrangement for a camshaft of an internal combustion engine, the internal combustion engine including a crankcase and a camshaft including a camshaft gear wheel and a side including a shaft end allocated to the camshaft gear wheel, includes: an axial bearing configured for supporting the camshaft on the side of the shaft end, the axial bearing including a plain bearing body, which includes a mounting surface, is crescent-shaped, and is configured for axially supporting the camshaft and for being attached to the crankcase by way of the mounting interface.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This is a continuation of PCT application no. PCT / EP2023 / 085434, entitled “BEARING ASSEMBLY FOR A CAMSHAFT OF AN INTERNAL COMBUSTION ENGINE, AND CRANKCASE COMPRISING SAME”, filed Dec. 12, 2023, which is incorporated herein by reference. PCT application no. PCT / EP2023 / 085434 claims priority to German patent application no. 10 2022 133 736.7, filed Dec. 16, 2022, which is incorporated herein by reference.BACKGROUND OF THE INVENTION1. Field of the Invention

[0002] The present invention relates to internal combustion engines.2. Description of the Related Art

[0003] Bearing arrangements of the aforementioned type are generally known and are used in engine construction to ensure an operationally stable and positionally precise arrangement of the camshaft in the crankcase. Since the camshaft controls the timing sequence of the engine's ignition points, a smooth operation and high reliability are of great importance.

[0004] While the known bearing arrangements generally perform their purpose satisfactorily, there is nevertheless a desire to improve the bearing arrangements in terms of cost efficiency, without compromising the quality and operational reliability of the bearing arrangement.

[0005] Accordingly, what is needed in the art is to reduce the disadvantages described above as far as possible in a bearing arrangement of the type mentioned at the outset. In particular, what is needed in the art is a bearing arrangement that allows for simplified maintenance and assembly without impairing the running quality of the camshaft.SUMMARY OF THE INVENTION

[0006] The present invention relates to a bearing arrangement for a camshaft of an internal combustion engine, wherein the internal combustion engine has a crankcase, the camshaft has a camshaft gear wheel and a shaft end allocated to the cam shaft gear wheel, and wherein the bearing arrangement has an axial bearing which is designed to support the camshaft on the side of the shaft end.

[0007] The present invention provides a bearing arrangement for a camshaft of an internal combustion engine, wherein the internal combustion engine has a crankcase and a camshaft which has a camshaft gear wheel and a shaft end allocated to a cam shaft gear wheel, and wherein the bearing arrangement has an axial bearing which is designed to support the camshaft on a side of the shaft end, characterized in that the axial bearing has a crescent-shaped plain bearing body designed to axially support the camshaft and to be attached to the crankcase by way of a mounting interface.

[0008] In a first further development, the camshaft has a bearing groove that is circumferentially incorporated into the camshaft. The crescent-shaped plain bearing body is designed to be inserted into the bearing groove for axial support of the camshaft, to support the camshaft axially when inserted, and to be attached—in the inserted state—to the crankcase by way of the mounting interface when inserted.

[0009] Alternatively, the present invention proposes that instead of the camshaft, the plain bearing body is equipped with the bearing groove and is designed to be slid onto a corresponding shoulder of the camshaft for axial support of the camshaft, to axially support the camshaft in the slid-on state, and to be attached to the crankcase in the slid-on state by way of a mounting interface. Accordingly, the following considerations and optional embodiments also apply to this alternative.

[0010] The present invention is based on the realization that conventional axial bearings-due to their reduced number of parts compared to roller bearings, which however overall is still quite high-involve an assembly effort that can be optimized. In conventional axial bearings, where rotating parts are to be supported axially on stationary parts, the axial bearings were designed as dedicated components, whereby always a stationary part had be attached to a first component and a rotating part was attached to the second, rotating component, wherein these stationary and rotating components of the axial bearing were designed as single or multiple parts respectively, and frequently had additional interaction elements, forming the sliding surface or other bearing surfaces.

[0011] The present invention separates from the conventional concept in that the axial bearing is formed by only two mechanical elements when including the camshaft. Strictly speaking, the axial bearing consists of only one single component, namely the crescent-shaped plain bearing body, which engages in the groove with its bearing surfaces which are adapted to the groove.

[0012] In the concept of the current invention the term crescent-shape is understood to mean that the plain bearing body has a section with a substantially semicircular contour that conforms to the surrounding bearing groove, in particular has an identical curvature.

[0013] Optimization of cost efficiency has already been achieved through parts reduction.

[0014] A further optimization of cost efficiency is achieved in that the crescent-shaped plain bearing can be laterally inserted into the bearing groove, namely in a radial or radial / tangential motion. This allows for the camshaft and crankcase to be mounted and to be inserted into the predetermined position in the crankcase. Once the bearing groove is arranged approximately in the designated assembly position, the plain bearing body can be meshed with the camshaft by inserting it into the bearing groove. Since the camshaft is still movable in the axial direction at this point, assembly of the unit consisting of camshaft and plain bearing body can then be accomplished in a single step by attaching the plain bearing body with the mounting interface to the crankcase.

[0015] This also expedites and simplifies assembly, resulting in a further improvement in cost efficiency. At the same time, the plain bearing body remains more easily accessible for maintenance work.

[0016] If reference is made to an axial direction in connection with the present invention, this is to be understood to be the direction of the rotational axis of the camshaft. Equally, a radial or tangential movement is always understood as a movement relative to the rotational axis of the camshaft.

[0017] The present invention is advantageously further developed in that the mounting interface has a contact surface, wherein the crankcase has a corresponding contact surface, which is arranged optionally on a wall of the crankcase.

[0018] In optional embodiments, a side wall, end wall, or another separating wall in the crankcase is used as the crankcase wall. The wall can close off partial volumes of the crankcase or the entire crankcase, or only certain areas of the crankcase. As an alternative to a wall, other structures that provide rigidity to the crankcase, such as struts or ribs for supporting the camshaft in general, and the axial bearing in particular, can also be used.

[0019] In one optional embodiment, the plain bearing body is designed to be axially screwed to the crankcase. The position of the plain bearing body on the crankcase can be very precisely defined by mechanical processing of the contact surfaces of the mounting interface and the crankcase. This avoids establishment of longer tolerance chains, which are unavoidable in conventional axial bearings. The axial screw connection of the plain bearing body to the crankcase also facilitates assembly of the unit consisting of camshaft and plain bearing body.

[0020] In a further optional embodiment, the mounting interface on the plain bearing body has a number of through-bores in a predetermined pattern, which extend in axial direction from a first side that faces away from the contact surface to a second side of the plain bearing body that faces toward the contact surface, and wherein the crankcase has a number of threaded holes in the same pattern.

[0021] It can be advantageous to introduce the round holes that define the pattern in a single processing step into the plain bearing body and the crankcase. In optional embodiments, the holes of the pattern, in other words the through-bores in the plain bearing body and the threaded holes in the crankcase, are arranged on a common pitch circle around the camshaft axis.

[0022] In a further optional embodiment, the plain bearing body features an increased material thickness in axial direction in the region of the mounting interface, optionally designed as a protrusion on the first side. The regions of increased material thickness advantageously result in an increase in the grip length for the screw connection. The material reinforcements can be designed to be integral on the plain bearing body if, for example, it is a cast part. Alternatively, they can also be provided additionally on the plain bearing body, for instance, by way of discs or sleeves that are arranged on the plain bearing body or are firmly connected to it.

[0023] In an optional version, the plain bearing body can be provided as a cast part, or in another optional version as a sheet metal part; in both versions, precise shaping and machining of the relevant contact surfaces and bearing surfaces is possible even in high quantities.

[0024] In a further optional embodiment, the plain bearing body has a first bearing surface and a second bearing surface opposite the first bearing surface, the bearing groove has two opposite groove edges, and the bearing surfaces each face one of the groove edges in the inserted state of the plain bearing body. The groove edges and the plain bearing surfaces are optionally arranged parallel to each other. A surface of the plain bearing body, and a groove edge facing toward the latter respectively provide a plain bearing surface pairing.

[0025] In an optional embodiment, the (first) axial distance between the opposite groove edges is greater than the (second) axial distance between the opposite bearing surfaces of the plain bearing body, wherein the first axial distance is optionally greater within a range of 0.01 to 0.5 mm than the second distance, so that, in the inserted state, an axial bearing gap can form between the bearing surfaces and the groove edges respectively. Furthermore, the axial bearing gap on both sides of the bearing surfaces is optionally 0.025 mm to 0.4 mm or more, especially optionally 0.05 mm to 0.2 mm.

[0026] In a further optional embodiment, the axial bearing is a fluid-lubricated axial bearing, and the plain bearing body has a fluid channel that can be connected in a fluid-conducting manner to a lubricant supply, wherein the fluid channel has at least one outlet for each bearing surface that opens into the bearing surface. The output of lubricant to both bearing surfaces via the fluid channel has the advantage that a fluid film can form on both sides of the plain bearing body at the respective groove edges, which simultaneously favors or causes a hydrodynamic centering of the plain bearing body in the bearing gap that is formed by the groove edges. It is particularly optional if the outlets of the fluid channel are each aligned symmetrically, and especially optional if they are aligned with each other towards the opposite sides of the plain bearing body.

[0027] In a further optional embodiment, the plain bearing body has an inlet side and an outlet side in circumferential direction relative to the direction of rotation of the camshaft. In the context of the present invention, direction of rotation refers to the direction in which the camshaft rotates for the majority of the operating time in normal operation of the engine.

[0028] The outlets of the fluid channel are optionally positioned closer to the inlet side than to the outlet side. This is advantageous for lubricant distribution along the bearing gaps.

[0029] As previously indicated, the outlets of the fluid channel are optionally aligned coaxially to one another in an optional embodiment.

[0030] In a further optional embodiment, the bearing surfaces have an end face in circumferential direction at their inlet end, where a chamfer is formed at each, wherein the chamfer optionally has an angle of 2° to 10°, especially optionally of 4° to 6°, so that the plain bearing body is tapered in a wedge shape at the inlet end. The wedge-shaped taper provided by the chamfers has the advantage that the assembly, in other words, insertion of the plain bearing body into the bearing groove, is clearly simplified. On the other hand, the wedge-shaped taper contributes to the fact that during operation, i.e., when the camshaft is rotating, lubricant that is not introduced into the gap through the fluid channel, but rather is swirled up due to the rotating parts in the engine housing and impacts the inlet side of the axial bearing, is drawn into the wedge acting as a funnel due to the rotation of the camshaft, which further improves the lubrication of the axial bearing.

[0031] In one optional embodiment, the bearing arrangement includes a radial bearing for the camshaft, particularly in the region of the shaft end, wherein the radial bearing supports the camshaft radially at the crankcase. In this type of embodiment, the radial bearing is optionally arranged in a bearing seat of the crankcase, and the axial bearing is arranged in axial direction between the radial bearing and the camshaft gear.

[0032] In an optional embodiment, the radial bearing is arranged in the wall of the crankcase, to which the axial bearing with its mounting interface is also attached from the direction of one of the axial end faces. Thus, the camshaft gear wheel and the axial bearing are located optionally on the same side relative to the wall of the crankcase where the radial bearing is located, which further simplifies both assembly and maintenance. To service or replace the axial bearing, simply remove the camshaft gear from the face of the shaft end, and the entire axial bearing is exposed on the wall of the crankcase.

[0033] The axial bearing is optionally aligned such that the plain bearing body engages under the camshaft. In other words, the plain bearing body wraps around the camshaft-with respect to the direction of gravity in the operational orientation of the crankcase-from below. The crescent shape causes the plain bearing body to form a trough. This has the advantage that less oil escapes both during operation and at standstill. This is particularly advantageous after standstill periods, in that emergency lubrication is ensured until sufficient oil pressure in the lubrication supply of the bearing arrangement is established after engine start, optionally within 15 to 20 seconds after engine start.

[0034] The present invention was described above in a first aspect, with reference to a bearing arrangement. In a second aspect, the present invention further relates to a crankcase of an internal combustion engine, with a camshaft, a camshaft gear wheel, fixed to the camshaft for driving the camshaft, and a bearing arrangement.

[0035] According to the second aspect, the present invention further provides that the bearing arrangement is designed according to one of the previously described embodiments.

[0036] The present invention exploits the same advantages concerning the second aspect as the bearing arrangement according to the first aspect. Optional embodiments of the bearing arrangement of the first aspect are also optional embodiments of the crankcase according to the second aspect and vice versa, which is why reference is made to the above descriptions in order to avoid repetitions.

[0037] Due to the fact that, in the crankcase according to the present invention, the camshaft has the camshaft gear wheel and a shaft end allocated to the camshaft gear wheel, and that the bearing arrangement includes the axial bearing, which axially supports the camshaft on the side of the shaft end, whereby the camshaft has the bearing groove that is circumferentially introduced into the camshaft, and the axial bearing has the crescent-shaped plain bearing body that is inserted into the bearing groove for axial support of the camshaft, axially supports the camshaft and is fixed to the crankcase via the mounting interface, a reliable support of the camshaft is achieved, which, compared to conventional axial bearings, is significantly easier to install and maintain without including the quality of the axial positioning of the camshaft.

[0038] The plain bearing body does not need to be pressed in but can be screwed axially to the crankcase. The fluid channel of the plain bearing body can be connected to a lubrication supply with minimal effort, wherein the fluid channel ensures lubrication of the plain bearing.

[0039] Embodiments of the present invention are described below with reference to the drawings in comparison to the prior art, which is also partially illustrated.

[0040] With regard to additions to the teachings that can be directly inferred from the drawings, reference is made to the relevant state of the art. It is thereby to be considered that numerous modifications and changes regarding the design and detail of an embodiment can be made without departing from the general concept of the present invention.

[0041] The general concept of the present invention is not limited to the exact design or detail of the optional embodiment shown and described below, nor is it limited to an object that would be restricted compared to the object claimed in the claims. In the case of specified measurement ranges, values within the stated limits are to be disclosed as threshold values that can be used and claimed randomly.BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:

[0043] FIG. 1 is a schematic spatial representation of a crankcase according to an optional design example;

[0044] FIG. 2 is a partially sectioned schematic top view of the crankcase according to FIG. 1, from a different perspective;

[0045] FIG. 3 is a partially sectioned schematic top view of the crankcase according to FIG. 1 and FIG. 2, from a different perspective;

[0046] FIG. 4 is a partially sectioned schematic top view of the crankcase according to FIG. 1 to FIG. 3, from a different perspective;

[0047] FIGS. 5A and 5B are top views onto a wall of the crankcase according to FIG. 1 to FIG. 3 with camshaft gear wheel removed; and

[0048] FIGS. 6A, 6B, and 6C are various partial sectional views of a plain bearing body for the crankcase represented in FIG. 1 to FIGS. 5A, 5B.

[0049] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate at least one embodiment of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.DETAILED DESCRIPTION OF THE INVENTION

[0050] FIG. 1 shows crankcase 1 of internal combustion engine 100. Crankcase 1 has a wall 3 in which camshaft 5 is mounted by way of a bearing arrangement (see FIG. 2 to FIG. 6).

[0051] Camshaft 5 has shaft end 7 to which camshaft gear wheel 9 is attached. Camshaft gear wheel 9 is designed to be driven by way of a transmission and to rotate camshaft 5 in direction of rotation B about a rotation axis A. Crankcase 1 can be closed with one or more covers which however are not necessary for explanation of the present invention and are therefore not shown.

[0052] As can be seen from FIG. 2 to FIG. 5, axial bearing 11 is arranged between camshaft gear wheel 9 and wall 3. Axial bearing 11 has a crescent-shaped plain bearing body 13. Plain bearing body 13 has a bearing section 15 that is inserted into bearing groove 17, which is provided circumferentially on camshaft 5.

[0053] Plain bearing body 13 moreover has a mounting interface 19, by way of which plain bearing body 13 is attached to wall 3.

[0054] The assembly optionally is performed in such a way that camshaft 5 is pushed into its approximate designated operating position in the direction of axis A. Then, optionally with camshaft gear wheel 9 not yet assembled, plain bearing body 13 is engaged laterally with camshaft 5 so that bearing portion 15 dips into bearing groove 17.

[0055] Plain bearing body 13 is then brought into contact with wall 3 via the mounting interface and attached, for example, axially screw-fastened, as shown in the present design example. For this purpose, the bearing arrangement has a number, in particular a plurality, of screws 21 that are installed along a predetermined pattern on plain bearing body 13 and on wall 3.

[0056] To accommodate plain bearing body 13, wall 3 has a contact surface 23 corresponding to mounting interface 19 of the latter, which can be designed as one piece or segmented into several spaced-apart parts. After mounting plain bearing body 13 and securing it to wall 3, camshaft gear wheel 9 can finally be connected in a known manner with shaft end 7 of camshaft 5.

[0057] Meshing of plain bearing body 13 into camshaft 5, particularly into its bearing groove 17, is shown in more detail in FIG. 3 and FIG. 4.

[0058] Bearing groove 17 has a groove bottom 25, as well as a first groove edge 27 and a second groove edge 29 arranged opposite.

[0059] Edges 27, 29 are optionally axially aligned with their surface-normal and parallel to each other.

[0060] Bearing section 15 has a first bearing surface 31 and an opposite second bearing surface 33. First bearing surface 31 is optionally oriented towards groove edge 27, while second bearing surface 33 is oriented towards second groove edge 29. Bearing surfaces 31, 33 are optionally aligned axially with their surface normal and are parallel to each other.

[0061] Camshaft 5 is supported radially in wall 3 of crankcase 1 by way of a radial bearing 34 designed as a plain bearing, so that axial bearing 11 acts adjacent and at a distance from radial bearing 34 on one hand and camshaft gear wheel 9 of camshaft 5 on the other.

[0062] Seating of camshaft 5 is ensured through precision machining of contact surface 23 of wall 3 on one the hand and dimensional machining of mounting interface 19 on the other. As further illustrated in FIG. 4, screws 21 extend axially from a first side S1 of plain bearing body 13 to a second side S2 of the plain bearing body (compare FIG. 6).

[0063] The material thickness in the radial outer region of bearing body 13, in other words, radially outside bearing section 15, has an increased material thickness in axial direction, which results in higher stability of bearing body 13 and an increased gripping length for screws 21.

[0064] FIG. 3 and FIG. 4 show a cross section through crankcase 1 along axis A.

[0065] The region of increased material thickness extends as a protrusion towards axis A on first side S1 of plain bearing body 13.

[0066] FIG. 5-specifically divided into FIG. 5A and FIG. 5B shows the crescent-shaped structure of plain bearing body 13. The term crescent-shape describes that bearing section 15 takes an essentially semicircular progression in order to best fit into bearing groove 17. It is possible—and provided in optional versions—to extend the shoulders at an inlet side 37 and an outlet side 39 positioned opposite in the circumferential direction. However, the arc of contact that bearing section 15 takes around camshaft 5 in bearing groove 17 remains limited to 180° or less to maintain assembly capability.

[0067] FIG. 5A shows a top view of a plain bearing body in its mounted position on wall 3 of crankcase 1 with blocked out camshaft gear wheel 9.

[0068] Plain bearing body 13 is designed approximately semicircular from inlet side 37 to outlet side 39 in operating rotation direction B. Axial bearing 11 shown in FIG. 5A and FIG. 5B is fluidically connected to a lubrication source 43 via a supply channel 41 in wall 3 of crankcase 1 for the supply of lubricant.

[0069] As shown, the outer contour of the plain bearing body can also be designed to be essentially semicircular. However, the exact contour along mounting interface 19 with screw fittings 21 is not functionally essential for the bearing itself, but is rather of economic interest in regard to manufacturing and depends on the configuration of screws 21, supply channel 41, etc.

[0070] As shown in FIG. 5B, plain bearing body 13 has a fluid channel 45 as shown in the cross section of its interior, through which lubricant is directed towards inlet side 37 in the direction of arrow P1.

[0071] At inlet side 37, plain bearing body 13 has two outlets 47, 49, one of which opens towards first side S1 and the other towards second side S2 into bearing surfaces 31, 33, with outlets 47, 49 being coaxially aligned, symmetrically to each other.

[0072] By symmetrically introducing lubricant through fluid channel 45 and outlets 47, 49, a hydrodynamic centering of plain bearing body 13 in bearing groove 17 is achieved when camshaft 5 rotates at the intended operational speed. Fluid channel 45 can, as shown in the illustrated embodiment, be designed as a combination of fluid-conductive connected linear bores, which are sealed at the ends with suitable plugs.

[0073] Since the distance between bearing surfaces 31, 33 in axial direction is somewhat less than the distance between corresponding groove edges 27, 29 of bearing groove 17, a bearing gap is formed on both sides of bearing section 15 of plain bearing body 13, which is filled with lubricant during operation to enable essentially frictionless gliding of camshaft 5 in axial bearing 11.

[0074] FIG. 6 shows several additional details of plain bearing body 13 for the bearing arrangement and the crankcase of FIGS. 1 to 5. FIG. 6 is divided into the three details: FIGS. 6A, 6B, and 6C. In FIG. 6A, first side S1 of plain bearing body 13 is shown.

[0075] Radially outside adjacent to bearing section 15 is the region of the assembly interface described above with increased material thickness. At the points where screws 21 (see FIG. 1 to FIG. 5) are to be passed through the corresponding through-holes 35 of plain bearing body 13, a raised eye 51 with a supporting surface 53 is formed on first side S1, with supporting surface 53 being designed to fit against a screw head of screws 21.

[0076] In FIG. 6A, the view of first outlet 47 for the lubricant is moreover made available.

[0077] FIG. 6B shows a cross-section through plain bearing body 13, again illustrating the progression of fluid channel 45. Fluid channel 45 has a first sub-channel 45a and a second sub-channel 45b, which are each tightly sealed at the end by appropriate plugs 55.

[0078] FIG. 6C shows the view from the outside onto second side S2 of plain bearing body 13. Second side S2, has a flat surface 57 that transitions in a continuous manner into bearing surface 31, optionally forming a continuous flat surface with it.

[0079] On inlet side 37, bearing surface 31 has a front side 59, on which a bevel 61 is arranged both on first side S1 and on second side S2. Bevels 61 each optionally have an angle relative to respective bearing surface 31, 33 of 2° to 10°, optionally 4° to 6°, optionally 5°, thereby creating a wedge-shaped taper towards front side 59. This simplifies the insertion of plain bearing body 13 into bearing groove 17.

[0080] In addition, inlet 63 of fluid channel 45 is shown in FIG. 6C, which can be fluidically connected to lubricant source 43 and supply channel 41, from which the lubricant can be conveyed through fluid channel 45 to outlets 47, 49.

[0081] The arrangement outlined in FIG. 1 to FIG. 6 can be easily transformed in a short time from a fully disassembled to a fully assembled state with just a few manipulations and can be maintained easily and manufactured at low cost. The quality of the axial bearing is in no way inferior to conventional axial bearings.COMPONENT IDENTIFICATION LISTING1 Crankcase

[0083] 3 wall

[0084] 5 camshaft

[0085] 7 shaft end

[0086] 9 camshaft gear wheel

[0087] 11 axial bearing

[0088] 13 plain bearing body

[0089] 15 bearing section

[0090] 17 bearing groove

[0091] 19 mounting interface

[0092] 21 screws

[0093] 23 contact surface

[0094] 25 groove bottom

[0095] 27 first groove edge

[0096] 29 second groove edge

[0097] 31 first bearing surface

[0098] 33 second bearing surface

[0099] 34 plain bearing / radial bearing

[0100] 35 through-bore

[0101] 37 inlet side

[0102] 39 outlet side

[0103] 41 supply channel

[0104] 43 lubricant source

[0105] 45 fluid channel

[0106] 45a first partial channel

[0107] 45b second partial channel

[0108] 47,49 outlets

[0109] 53 support surface

[0110] 55 plug

[0111] 57 flat surface

[0112] 59 end face

[0113] 61 chamfer

[0114] 100 combustion engine

[0115] A rotational axis

[0116] B operational direction of rotation

[0117] P1 arrow

[0118] S1 first side

[0119] S2 second side

[0120] While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.

Claims

1. A bearing arrangement for a camshaft of an internal combustion engine, the internal combustion engine including a crankcase and a camshaft including a camshaft gear wheel and a side including a shaft end allocated to the camshaft gear wheel, the bearing arrangement comprising:an axial bearing configured for supporting the camshaft on the side of the shaft end, the axial bearing including a plain bearing body, which includes a mounting surface, is crescent-shaped, and is configured for axially supporting the camshaft and for being attached to the crankcase by way of the mounting interface.

2. The bearing arrangement according to claim 1, wherein the camshaft includes a bearing groove that is circumferentially incorporated into a circumference of the camshaft, the plain bearing body (a) is configured for being inserted into the bearing groove for an axial support of the camshaft in order to support the camshaft axially in an inserted state of the plain body bearing, and (b) is configured for being attached in the inserted state to the crankcase by way of the mounting interface.

3. The bearing arrangement according to claim 1, wherein the plain bearing body includes a bearing groove and is configured for being slid onto a corresponding shoulder of the camshaft for an axial support of the camshaft, for axially supporting the camshaft in a slid-on state, and for being attached to the crankcase in the slid-on state by way of the mounting interface.

4. The bearing arrangement according to claim 1, wherein the mounting interface includes a contact surface corresponding to a contact surface of the crankcase.

5. The bearing arrangement according to claim 4, wherein the plain bearing body is configured for being axially screwed to the crankcase.

6. The bearing arrangement according to claim 5, wherein the plain bearing body includes an axial direction and a region of the mounting interface, wherein the plain bearing body includes an increased material thickness in the axial direction in the region of mounting interface.

7. The bearing arrangement according to claim 6, wherein the plain bearing body includes a first side, the increased material thickness being formed as a protrusion on the first side.

8. The bearing arrangement according to claim 1, wherein the plain bearing body includes a first bearing surface and a second bearing surface opposite first bearing surface, wherein the camshaft includes a bearing groove that is circumferentially incorporated into a circumference of the camshaft, the bearing groove including two groove edges opposite one another, and wherein the first bearing surface and the second bearing surface in an inserted state each facing respectively one of the two groove edges.

9. The bearing arrangement according to claim 8, wherein an axial distance between opposite ones of the two groove edges is greater than an axial distance between opposite ones of the first bearing surface and the second bearing surface, such that, in the inserted state, the bearing arrangement is configured such that an axial bearing gap forms between the first bearing surface and the second bearing surface and the two groove edges respectively.

10. The bearing arrangement according to claim 9, wherein the plain bearing body includes a fluid channel that can be connected in a fluid-conducting manner to a lubricant supply, wherein the fluid channel includes a first outlet and a second outlet respectively for the first bearing surface and the second bearing surface, the first outlet and the second outlet opening respectively into the first bearing surface and the second bearing surface.

11. The bearing arrangement according to claim 10, wherein the plain bearing body includes an inlet side and an outlet side in a circumferential direction of the plain bearing body relative to a direction of rotation of the camshaft.

12. The bearing arrangement according to claim 11, wherein the first outlet and the second outlet are positioned closer to the inlet side than to the outlet side.

13. The bearing arrangement according to claim 12, wherein the first outlet and the second outlet are aligned coaxially relative to one another.

14. The bearing arrangement according to claim 8, wherein the first bearing surface and the second bearing surface have an inlet end and an end face in a circumferential direction of the plain bearing body at the inlet end, where a chamfer is formed respectively, such that the plain bearing body is tapered in a wedge shape at the inlet end.

15. The bearing arrangement according to claim 1, wherein the bearing arrangement further includes a radial bearing on the side of the shaft end, which supports the camshaft radially at the crankcase, wherein the radial bearing is arranged in a bearing seat of the crankcase, and wherein the axial bearing is arranged between the radial bearing and the camshaft gear wheel.

16. An internal combustion engine, comprising:a crankcase;a camshaft;a camshaft gear wheel, which is attached to the camshaft and is configured for driving the camshaft, the camshaft including a side including a shaft end allocated to the camshaft gear wheel; anda bearing arrangement for the camshaft, the bearing arrangement including an axial bearing configured for supporting the camshaft on the side of the shaft end, the axial bearing including a plain bearing body, which includes a mounting surface, is crescent-shaped, and is configured for axially supporting the camshaft and for being attached to the crankcase by way of the mounting interface.

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