DE102022001586A1 - Internal combustion engine for a motor vehicle - Google Patents

Abstract

The invention relates to an internal combustion engine (10) for a motor vehicle, with a gear drive (24), via which at least one shaft (20) and/or at least one auxiliary unit can be driven by an output shaft (14) of the internal combustion engine (10), with tooth flanks ( 30) a toothing (28) of at least one gear (26a-c) of the gear drive (24) is coated with graphene (32).

Description

The invention relates to an internal combustion engine for a motor vehicle according to the preamble of patent claim 1.

Such internal combustion engines for motor vehicles are already well known from the general state of the art. The respective internal combustion engine has a gear drive, also known as a gear drive, via which at least one shaft, such as a camshaft and / or at least one auxiliary unit, can be driven by an output shaft of the internal combustion engine, for example designed as a crankshaft.

Furthermore, the reveals DE 10 2015 005 133 A1 a method for producing a gear, in which a component blank with a shape close to the final contour is produced. Furthermore, it is provided that at least one powdery material is melted and applied as a coating to at least one area of the component blank produced.

The object of the present invention is to improve an internal combustion engine of the type mentioned at the outset.

This task is achieved by an internal combustion engine with the features of patent claim 1. Advantageous embodiments with useful developments of the invention are specified in the remaining claims.

In order to improve an internal combustion engine of the type specified in the preamble of claim 1, it is provided according to the invention that the tooth flanks of a toothing of at least one gear of the gear train is coated with graphene. This makes it possible to achieve a high level of wear resistance and a high level of durability of the teeth and thus of the gear. In addition, the generation of undesirable noises can be avoided, so that a particularly advantageous noise behavior of the internal combustion engine can be achieved. The invention is based in particular on the following findings and considerations: Gear drives in internal combustion engines, also known as internal combustion engines, for example as a camshaft drive, as drives for an oil pump, as a mass balancing gear, etc., are always in a conflict of objectives in the design with regard to noise, backlash, wear and durability. In other words, it is desirable, on the one hand, to avoid excessive wear and thus to create a high level of durability. On the other hand, it is desirable to avoid excessive backlash and thus the generation of undesirable noises. This conflict of objectives can be resolved or significantly shifted by the invention. The very resistant graphene creates a particularly wear-resistant surface of the gearing, whereby the surface formed by the graphene is, on the one hand, harder than classic, hardened layers. On the other hand, the graphene is advantageously elastic. The graphene can therefore be used to create an ultra-hard yet elastic surface of the toothing.

According to the invention, the graphene forms a coating which can be thinner compared to conventional solutions because graphene is significantly more wear-resistant than other conventional coatings. This also means that there is less wear residue in an oil circuit. The invention can also be used to set the backlash to a long-term compromise than with conventional solutions, since less wear can be expected, which negatively influences the backlash and thus also the noise. The positive properties of a hard surface for precision can be combined with the elastic properties that have a positive effect on acoustics. This means that, on the one hand, undesirable noises can be avoided, and on the other hand, a high level of wear resistance and thus a high level of durability of the wheel drive can be achieved.

Further advantages, features and details of the invention result from the following description of a preferred exemplary embodiment and from the drawing. The features and combinations of features mentioned above in the description as well as the features and combinations of features mentioned below in the description of the figures and/or shown in the figures alone can be used not only in the combination specified in each case, but also in other combinations or on their own, without the scope of to abandon invention.

• 1 eine schematische und geschnittene Seitenansicht einer Verbrennungskraftmaschine mit einem Rädertrieb; und
• 2 ausschnittsweise eine schematische und geschnittene Vorderansicht eines Zahnrads des Rädertriebs.

The drawing shows in:

• 1 a schematic and sectional side view of an internal combustion engine with a gear drive; and
• 2 a detail of a schematic and sectioned front view of a gear of the gear train.

In the figures, identical or functionally identical elements are provided with the same reference numerals.

1 shows a schematic and sectional side view of an internal combustion engine 10 designed as a reciprocating piston engine for a motor vehicle, in particular for a motor vehicle. This means that the motor vehicle, which is preferably designed as a motor vehicle, in particular as a passenger car, has the internal combustion engine 10 in its completely manufactured state and can be driven by means of the internal combustion engine 10. The internal combustion engine 10 has a housing 12 designed, for example, as a cylinder housing, in particular as a cylinder crankcase, which is also referred to as an engine block. Furthermore, the internal combustion engine 10 has an output shaft 14, in the present case designed as a crankshaft, via which the internal combustion engine 10 can provide torque for driving the motor vehicle. The output shaft 14 is rotatably mounted on the housing 12 about an output shaft rotation axis 16 relative to the housing 12. In the present case, the output shaft 14 is articulated via connecting rods (not shown in the figures) to pistons (not shown in the figures) of the internal combustion engine 10, the combustion chambers of which are partly delimited by the pistons and partly by the housing 12. The internal combustion engine 10 also has a housing element, in the present case designed as a cylinder head 18, which is designed separately from the housing 12 and is connected to the housing 12. The respective combustion chamber is partially delimited by a respective combustion chamber roof, the respective combustion chamber roof being formed by the cylinder head 18. The internal combustion engine 10 has at least one shaft, in the present case designed as a camshaft 20, which is rotatably mounted on the cylinder head 18 about a camshaft rotation axis 22 relative to the cylinder head 18. By means of the camshaft 20, respective gas exchange valves of the respective combustion chamber can be actuated, in particular opened.

The internal combustion engine 10 also has a gear drive 24, which is also referred to as a gear drive. The camshaft 20 can be driven by the output shaft 14 via the gear drive 24 and can therefore be rotated about the camshaft rotation axis 22 relative to the cylinder head 18. For this purpose, the wheel drive 24 includes gears 26a-c, which have respective teeth, in particular external teeth.

In 2 For example, the gear 26a is shown in detail in a front view, with the teeth of the gear 26a in 2 is designated 28. The gear 26a is non-rotatably connected to the output shaft 14, and the gear 26c is, for example, non-rotatably connected to the camshaft 20. The previous and following statements about the gear 26a and its teeth 28 can easily be transferred to the other gears 26b and 26c of the gear train 24 and vice versa. Alternatively or additionally, it is conceivable that at least one auxiliary unit can be driven by the output shaft 14 via the gear drive 24. The auxiliary unit can be, for example, a liquid pump, in particular an oil pump or water pump, or a mass balancer, or another auxiliary unit.

In order to be able to achieve a particularly high level of wear resistance and a high level of durability of the gear drive 24 as well as a particularly advantageous noise behavior of the internal combustion engine 10, these are particularly good 2 can be seen, at least tooth flanks 30 of the toothing 28 are coated with graphene. This means that the graphene forms a coating 32, also known as a graphene coating, with which the tooth flanks 30 are provided and therefore coated. The graphene, hence the coating 32, forms a surface 34 of the toothing 28, the surface 34 of which is, on the one hand, ultra-hard and, on the other hand, advantageously elastic. This allows unwanted noises to be avoided. In addition, excessive wear of the teeth 28 can be avoided.

Reference symbol list

10

Internal combustion engine

12

Housing

14

output shaft

16

Output shaft rotation axis

18

cylinder head

20

camshaft

22

Camshaft rotation axis

24

Wheel drive

26a-c

gear

28

gearing

30

tooth flank

32

Coating

34

surface

QUOTES INCLUDED IN THE DESCRIPTION

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

Cited patent literature

• DE 102015005133 A1 [0003]

Claims (2)

Internal combustion engine (10) for a motor vehicle, with a gear drive (24), via which at least one shaft (20) and/or at least one auxiliary unit can be driven by an output shaft (14) of the internal combustion engine (10), characterized in that tooth flanks (30 ) a toothing (28) of at least one gear (26a-c) of the gear drive (24) is coated with graphene (32). Internal combustion engine (10). Claim 1 , characterized in that the toothing (28), with the exception of the tooth flanks (30), is free of a coating formed from graphene.

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