DE102020124847A1 - Timing adjustment system for an internal combustion engine - Google Patents

Abstract

The invention relates to a control timing adjustment system (1) for an internal combustion engine (2), having a camshaft (3) and a camshaft adjuster (4) coupled to the camshaft (3), with a stator (10) of the camshaft adjuster on an axial side (5). (4) a support area (7) further coupled to the camshaft (3) is arranged, which support area (7) is used directly for axial and/or radial support of the camshaft (3) relative to a component (8) fixed to the housing of the internal combustion engine (2) is prepared, and wherein the camshaft adjuster (4) is connected to the camshaft (3) by means of an anchor element (9) and a rotor (11) of the camshaft adjuster (4) which can be rotated to a limited extent relative to the stator (10) directly on a support area ( 7) having the base body (22) of the anchor element (9) or is at least partially formed integrally with this base body (22).

Description

The invention relates to a timing adjustment system for an internal combustion engine, such as an Otto or diesel engine, of a motor vehicle, with a camshaft and a camshaft adjuster coupled to the camshaft, with a camshaft further coupled/connected to a (first) axial side of a stator of the camshaft adjuster Support area is arranged, which support area is prepared directly for axial and / or radial support of the camshaft relative to a housing-fixed part of the internal combustion engine. The control time setting system that is the subject of the invention is alternatively also referred to as a camshaft setting system/camshaft adjustment system or as a kit consisting of a camshaft adjuster and a camshaft.

Generic tax timing adjustment systems are already well known from the prior art. Accordingly, for example, revealed the DE 10 2016 118 710 A1 a camshaft adjustment system for an internal combustion engine, in which a hydraulic valve is designed in operative connection with an actuator as a stop. Furthermore, the EP 1 596 040 B1 a camshaft adjuster which, together with a pressure medium distributor and a component fixed to the cylinder head, forms a camshaft axial bearing.

Consequently, designs are known from the prior art in which, outside of the camshaft adjuster, the camshaft is mounted on a component of the internal combustion engine that is fixed to the housing, such as a cylinder head. With these adjusters, however, it has been found that the existing connections between the camshaft adjuster and the central valve used, or between the central valve and the camshaft, are relatively complex to construct. Since the central valve forms a corresponding axial bearing in these designs, the manufacturing costs are also adversely affected.

It is therefore the object of the present invention to provide a control timing adjustment system with a camshaft adjuster and a camshaft whose components can be assembled as simply and quickly as possible.

According to the invention, this is achieved in that the camshaft adjuster is (indirectly) connected to the camshaft (arranged towards the first axial side or a second axial side of the camshaft adjuster facing away from the first axial side) by means of an anchor element and delimits a position relative to the stator rotatable rotor of the camshaft adjuster is fastened directly to a base body of the anchor element that has the support area, or is formed at least partially in one piece with this base body

As a result, an additional central valve body that fulfills the fastening tasks can be dispensed with, which in turn significantly reduces the manufacturing effort. Due to the direct coupling of the rotor to the anchor element forming the support area, the forces generated during operation are supported directly.

Further advantageous embodiments are claimed with the dependent claims and explained in more detail below.

Accordingly, it is also advantageous if the rotor is attached to the anchor element by means of an interference fit. As a result, the assembly effort is further reduced.

As an alternative to this, it is also advantageous if an annular body of the rotor/the rotor is designed as a one-piece material component of the base body of the anchor element. This enables even more robust storage.

In addition, it is advantageous if the support area has at least one axial bearing surface, which is in (direct) axial contact with the component that is fixed to the housing. As a result, the support area can be produced as simply as possible.

Furthermore, it is expedient if the support region even has two axial bearing surfaces which face away from one another (axially) and which are in axial contact with the component part which is fixed to the housing. As a result, the support area is secured completely axially to the component that is fixed to the housing.

It is also advantageous if the support area has a radial bearing surface that is in radial contact with the component that is fixed to the housing. At the same time, this results in a reliable centering of the anchor element/camshaft.

It is also advantageous if an actuator used to control the camshaft adjuster is connected to the component fixed to the housing and is arranged at a distance from the support area or is in direct contact with the support area. As a result, the actuator is accommodated directly on the component that is fixed to the housing. More preferably, this is also used directly for the axial support of the support area, which further simplifies the structure.

Consequently, it is advantageous for a variable usability of the control timing adjustment system if the camshaft adjuster is designed as a hydraulic camshaft adjuster or an electric camshaft adjuster. Accordingly, the actuator is designed either as a central magnet actuator that adjusts a (hydraulic) control valve, or as an electric servomotor.

It has also proven to be expedient if the support area has at least one radial collar (supported by the housing-fixed component) and/or at least one radial recess (supported by the housing-fixed component). As a result, the support area can be produced as easily as possible while forming a bearing area.

In order to further simplify production, it is also advantageous if the at least one radial collar is formed in one piece with the base body of the anchor element (more preferably also formed in one piece as a whole). As a result, the assembly effort is further reduced.

As an alternative or in addition to this, it is also advantageous if a radial collar is formed on a fastening nut screwed to the base body of the anchor element. This allows axial play to be set quickly and precisely.

In this regard, it has also been found to be expedient if the support area even has two axially spaced-apart radial flanges which are supported on mutually axially opposite mating surfaces of the component part fixed to the housing. This also enables an axial bearing that is as robust as possible.

As an alternative or in addition to the provision of at least one radial collar, it is also expedient if at least one recess is present (in the support area), into which a support web of the component part fixed to the housing preferably projects. As a result, the assembly process can be further simplified if necessary.

It is also expedient if the support area has two axially spaced (to each other) recesses, into each of which a support web of the housing-fixed component protrudes.

Furthermore, it has also proven to be advantageous for a simple structure if the housing-fixed component (for example if only one radial collar or one recess is provided) is located axially in contact with a stator-fixed component, such as a cover of the stator.

The anchor element (if the camshaft adjuster is designed as a hydraulic camshaft adjuster) more preferably has a receiving space that is open axially toward the actuator and in which a control valve that is operatively connected to the actuator is integrated.

In addition, it is expedient if the anchor element/the base body of the anchor element is connected to the camshaft via a non-positive and/or positive connection. This also further simplifies the manufacturing effort.

The invention will now be explained in more detail below with reference to figures, in which context various exemplary embodiments are also shown.

• 1 eine Längsschnittdarstellung eines erfindungsgemäßen Steuerzeiteneinstellsystems nach einem ersten Ausführungsbeispiel, wobei auch detailliert ein an einem Ankerelement ausgebildeter Stützbereich zu erkennen ist, der einen in einem gehäusefesten Bestandteil der Verbrennungskraftmaschine unmittelbar axial und radial abgestützten Radialbund aufweist,
• 2 eine Längsschnittdarstellung eines Teilbereichs eines erfindungsgemäßen Steuerzeiteneinstellsystems nach einem zweiten Ausführungsbeispiel, wobei der dargestellte Stützbereich des Ankerelementes nun eine Ausnehmung aufweist,
• 3 eine Längsschnittdarstellung eines Teilbereichs eines erfindungsgemäßen Steuerzeiteneinstellsystems nach einem dritten Ausführungsbeispiel, wobei der dargestellte Stützbereich des Ankerelementes zwei axial beabstandete Ausnehmungen aufweist,
• 4 eine Längsschnittdarstellung eines erfindungsgemäßen Steuerzeiteneinstellsystems nach einem vierten Ausführungsbeispiel, wobei der Stützbereich eine zusätzliche, an dem Ankerelement / einem Grundkörper des Ankerelementes verschraubte, einen Radialbund ausbildende Befestigungsmutter aufweist und der gehäusefeste Bestandteil zwischen diesem Radialbund und einem Deckel eines Stators des Nockenwellenverstellers aufgenommen ist,
• 5 eine Längsschnittdarstellung eines erfindungsgemäßen Steuerzeiteneinstellsystems nach einem fünften Ausführungsbeispiel, in dem der Grundkörper des Ankerelementes und eine daran befestigte Befestigungsmutter zusammen zwei Radialbünde ausbilden, sowie
• 6 eine Längsschnittdarstellung eines erfindungsgemäßen Steuerzeiteneinstellsystems nach einem sechsten Ausführungsbeispiel, in dem der Aktor unmittelbar zur axialen Sicherung des Stützbereiches mit eingesetzt ist.

Show it:

• 1 a longitudinal sectional view of a control timing adjustment system according to the invention according to a first embodiment, wherein a support area formed on an anchor element can also be seen in detail, which has a radial collar supported directly axially and radially in a part of the internal combustion engine that is fixed to the housing,
• 2 a longitudinal sectional view of a portion of a control timing adjustment system according to the invention according to a second embodiment, the illustrated support area of the anchor element now having a recess,
• 3 a longitudinal sectional view of a portion of a control timing adjustment system according to a third embodiment of the invention, the illustrated support area of the anchor element having two axially spaced recesses,
• 4 a longitudinal sectional view of a fourth exemplary embodiment of a control timing adjustment system according to the invention, with the support area having an additional fastening nut that is screwed to the anchor element/a base body of the anchor element and forms a radial collar, and the component that is fixed to the housing is accommodated between this radial collar and a cover of a stator of the camshaft adjuster,
• 5 a longitudinal sectional view of a fifth exemplary embodiment of a tax timing adjustment system according to the invention, in which the base body of the anchor element and a fastening nut attached to it together form two radial collars, and
• 6 a longitudinal sectional view of a tax timing adjustment system according to the invention according to a sixth exemplary embodiment, in which the actuator is also used directly for axially securing the support area.

The figures are only of a schematic nature and serve exclusively for understanding the invention. The same elements are provided with the same reference numbers. In principle, the different features of the various exemplary embodiments can also be freely combined with one another.

with 1 a structure of a tax timing adjustment system 1 according to the invention is illustrated according to a first exemplary embodiment. In this embodiment, the control timing adjustment system 1 is integrated in an indicated internal combustion engine 2 . The control timing adjustment system 1 typically serves to adjust a control timing of the internal combustion engine 2/a phase position of a camshaft 3 of the internal combustion engine 2 relative to a crankshaft. The crankshaft of the internal combustion engine 2 is rotationally coupled to a stator 10 of a camshaft adjuster 4 of the timing adjustment system 1 via an endless traction drive, not shown for the sake of clarity. A rotor 11 of the camshaft adjuster 4 that can be optionally adjusted relative to the stator 10 in a limited rotational angle range is in turn connected to the camshaft 3 in a rotationally fixed manner.

It should be noted that the structure of the tax timing adjustment system 1 described in more detail below 1 largely on the other embodiments of 2 until 6 applies, so that for the sake of brevity only the differences between these exemplary embodiments are described below.

with 1 It can be seen that the camshaft adjuster 4 is implemented as a hydraulic camshaft adjuster 4, namely as a camshaft adjuster 4 of the vane cell type. In addition to the camshaft adjuster 4, there is consequently also a central control valve 23 (also referred to as a central valve) in order to supply the hydraulic working chambers/partial chambers of the working chambers (not shown in detail for the sake of clarity) with hydraulic pressure during operation of the internal combustion engine 2 and thus to adjust the phase position of the camshaft 3 set specifically.

Furthermore, there is an actuator 19 that controls/adjusts the control valve 23 . In this embodiment, the actuator 19 is implemented as a central magnet actuator and is coupled in motion to a piston element 25 of the control valve 23 on the part of its axially extendable and retractable plunger 24 .

In this context, it should also be pointed out that the camshaft adjuster 4 is not limited to use as a hydraulic camshaft adjuster 4 and is more preferably implemented as an alternative electric camshaft adjuster in further embodiments according to the invention. When the camshaft adjuster 4 is realized as an electric camshaft adjuster, the actuator 19 is preferably designed as an electric servomotor that adjusts the electric drive/the electric adjustment of the rotor 11 relative to the stator 10 .

The camshaft 3 is coupled to the rotor 11 in a torque-proof manner via an anchor element 9 . The anchor element 9 has a base body 22 which connects the rotor 22 to the camshaft 3 . The base body 22 also has a (fully cylindrical) journal area 26 which is pushed into the hollow camshaft 3 and is connected to the camshaft 3 . For this rotary joint, a press joint or, more preferably, a combination of a non-positive and form-locking joint, for example a press joint with teeth engaging in a form-locking manner, is preferably implemented.

The base body 22 extends from the pin area 26 in the direction of the actuator 19. In turn, the piston element 25/the control valve 23 is seated in a cavity 27 formed in the base body 22. Axially spaced from the pin area 26 is on a radial outer side 28 of the base body 22 the rotor 11 is rotatably mounted. The rotor 11 is attached to the anchor element 9 via an interference fit 12 . In particular, the rotor is 11 in 1 recognizable as a ring body, on the radial outside of which, in the usual way, several wings are arranged distributed in the circumferential direction and not shown for the sake of clarity. In this connection it should be pointed out that the rotor 11 (in particular with its annular body) is also alternatively designed directly in one piece with the base body 22 / as a one-piece material component of the anchor element 9 in further embodiments according to the invention.

The anchor element 9 / the base body 22 penetrates the camshaft adjuster 4 axially. On a (first) axial side 5 of the camshaft adjuster 4 , the armature element 9 is mounted/supported axially and radially on a component 8 of the internal combustion engine 2 that is fixed to the housing. A support area 7 provided for this support is explained in more detail below. The support area 7 is thus located on a first axial side 5 of the camshaft adjuster 4; The anchor element 9 / the base body 22 is connected to the camshaft 3 on a second axial side 6 of the camshaft adjuster 4 facing away from the first axial side 5 .

The component 8 fixed to the housing supporting the support area 7 is preferably designed as a section of a cylinder head of the internal combustion engine 2 . The actuator 19 with its actuator housing 29 is also firmly accommodated in this part 8 fixed to the housing. For example, the actuator housing 29 is accommodated on the component 8 fixed to the housing via a bayonet connection.

In 1 the support area 7 is implemented by a single radial collar 17a. This radial collar 17a is converted to one end of the anchor element 9, which in this embodiment is made of one piece of material. In this embodiment, the base body 22 thus completely forms the anchor element 9 . The radial collar 17a is therefore also formed in one piece with the anchor element 9 .

The radial collar 17a forms a first axial bearing surface 14 in a first axial direction and a second axial bearing surface 15 in a second axial direction, which are supported on the mating contact surface 30a, 30b of the component 8 fixed to the housing. At the same time, a radial outer side of the radial collar 17a is in radial contact with the component 8 fixed to the housing, forming a radial bearing surface 16. As a result, the support area 7 and consequently the camshaft 3 are supported axially and radially on the component 8 fixed to the housing, forming a slide bearing .

It should also be pointed out that the support area 7 is arranged towards the second axial side 6 in further embodiments.

With the different versions of the 2 until 6 Various further variants for the formation of the support area 7 are illustrated.

Accordingly, it is according to the 2 and 3 As an alternative to the formation of a radial collar, it is in principle also advantageous if the support area 7 has at least one recess 20a, 20b, into which at least one recess 20a, 20b a support web 21a, 21b of the component 8 fixed to the housing protrudes and in turn ensures that the anchor element 9 is supported is.

2 shows that in a second exemplary embodiment, only a single recess 20a is made in the anchor element 9/the base body 22. A support web 21a of the component 8 fixed to the housing protrudes radially from the outside into this recess 20a. The recess 20a in turn forms the axial bearing surfaces 14, 15, which abut slidingly on the counter-abutment surfaces 30a, 30b formed by the support web 21a. A radial bearing surface 16 is formed, preferably axially following the recess 20a, via an outer lateral surface 32 of the anchor element 9.

According to the third embodiment of the 3 two axially spaced-apart recesses 20a, 20b are made in the anchor element 9/the base body 22, with a support web 21a, 21b of the component 8 fixed to the housing protruding into each recess 20a, 20b. A first recess 20a accommodates a first support web 21a; a second recess 20b accommodates a second support web 21b. Each recess 20a, 20b forms only one of the two axial bearing surfaces 14, 15. While the first recess 20a forms the first axial bearing surface 14, the second recess 20b forms the second axial bearing surface 15.

With the 4 until 6 are again alternatives to the radial collar 17a 1 implemented.

In the fourth embodiment, the radial collar 17a according to 4 formed on a separately molded member in the form of a fastening nut 13. The fastening nut 13 is in turn screwed to the base body 22 .

with 4 It can also be seen that the component 8 fixed to the housing is designed in such a way that it is supported directly on a cover 31 (front cover) of the stator 10 on a side facing away axially from the radial collar 17a. As a result, component 8 is supported axially between fastening nut 13/radial collar 17a and cover 31.

In the fifth embodiment of the 5 there are two axially spaced radial collars 17a, 17b on the part of the anchor element 9. The first radial collar 17a is secured by the fastening nut 13, as already shown in 4 , and the second radial collar 17b provided by the base body 22. The second radial collar 17b is formed as a one-piece material component of the base body 22 . The part 8 fixed to the housing is in turn accommodated/supported axially between these two radial collars 17a, 17b.

With the sixth embodiment of the 6 is, as already in 4 , only a radial collar 17a is used in the support area 7 . This radial collar 17a is now supported axially between the actuator housing 29 and the component 8 fixed to the housing. The two axial bearing surfaces 14, 15 are accordingly in turn both formed by the radial collar 17a. The first mating surface 30a is formed by the actuator housing 29, which is also to be regarded as a component part of the housing, while the second mating surface 30a continues through the housing-fixed component 8 is designed in the form of the cylinder head.

In other words, the axial bearing and/or the radial bearing for the VCCU assembly (assembly consisting of camshaft 3 and camshaft adjuster 4; VCCU stands for "Variable Camshaft Control Unit") is mounted directly on a rotor armature (armature element 9) that is in the Rotor 11 is pressed in axially and connects the rotor 11 to the camshaft 3 inextricably, is formed. The rotor armature has at least one radial rim (radial collar 17a, 17b) or at least one groove (recess 20a, 20b), in which at least one side surface is used as an axial bearing surface 14, 15 for the camshaft bearing.

In the axial section between the rotor 11 and the actuator/actuator 19, the rotor armature has at least one oil duct 18, preferably several oil ducts 18, in order to return the oil from the central valve to the tank and/or to the volume reservoir on the front side (first side 5) of the camshaft adjuster 4 enable.

The oil ducts 18 (/oil return ducts) connect the hollow inner area (cavity 27) of the rotor armature with the outside engine environment and can be made, for example, as radial bores in the rotor armature.

The axial and/or radial bearing is at least partially lubricated via these oil return channels. The oil channels 18 open out at least partially in the bearing area (/support area 7).

The second side surface of the rim or the groove on the rotor armature can also be used as the second axial bearing surface 15 . An outer diameter of the rotor armature or the rim or the groove can also be used as a radial bearing surface 16 for the camshaft 3 itself. Alternatively, a second rim (second radial collar 17b) or a second groove (second recess 20b) can be provided on the rotor armature, axially offset from the first rim or the groove, which forms the second axial bearing surface 15 on the camshaft bearing (/support area 7).

These solutions are suitable for the case in which the camshaft 3 can be inserted radially into the cylinder head during engine assembly and then fixed with the bearing shells. As soon as the camshaft 3 is joined axially during assembly in the cylinder head, at least one rim stands in the way of the assembly of the axial bearing bridge (part 8 fixed to the housing). A rotor armature with a rim and a detachable fastening nut 13 is preferably used for this assembly situation.

During assembly, the axial bearing is formed by a side surface of the rotor armature rim and the underside of the fastening nut 13, which is screwed into the rotor armature. As a result, the axial bearing gap can be adjusted in a targeted manner, because the stop surface for the fastening nut 13 and the side surface of the rim on the rotor armature can be produced very precisely in relation to one another in one production step. This considerably shortens the tolerance chain for the axial bearing gap and the axial bearing gap can be set particularly narrow. If necessary, e.g. in the case of rejects, the axial bearing can be easily dismantled again with the axial fastening nut 13.

Alternatively, the axial bearing can be formed between the fastening nut 13 and the front side of the front cover/cover 31 of the camshaft adjuster 4. The rotor armature can be placed with the camshaft bearing (support area 7) on the front side, e.g. between the bearing bracket (/part 8 fixed to the housing) and the camshaft adjuster 4, and on the back of the camshaft adjuster 4, i.e. between the camshaft adjuster 4 and the camshaft 3.

In order to further reduce the axial installation space in the system, the central magnet (actuator 19) can preferably also be pre-assembled with the bearing bracket and the VCCU assembly in the cylinder head. The central magnet can be centered in the bearing bridge and connected to it, e.g. via a bayonet lock.

The solution can also be used as an electric camshaft adjuster: instead of the central magnet, an electric motor (electric servomotor) is connected to the bearing bridge. A completely assembled assembly consisting of a central magnet or electric motor, bearing bracket, camshaft adjuster 4 with rotor armature and camshaft 3 is preferably added to the cylinder head in one step, without aligning and fastening individual system components to one another. Then only the bearing bridge needs to be positioned and fastened on the cylinder head.

In systems with a dry belt drive, the camshaft bearing can take on the function of a bearing bridge by means of a shaft seal ring holder, so that the radial shaft seal ring can seal the sealing collar through precise centering to the sealing collar on the camshaft adjuster 4 without any radial impact worth mentioning.

Reference List

1

timing adjustment system

2

internal combustion engine

3

camshaft

4

camshaft adjuster

5

first page

6

second page

7

support area

8th

component

9

anchor element

10

stator

11

rotor

12

press bandage

13

fastening nut

14

first thrust bearing surface

15

second thrust bearing surface

16

radial bearing surface

17a

first radial fret

17b

second radial collar

18

oil channel

19

actuator

20a

first recess

20b

second recess

21a

first support bar

21b

second support bar

22

body

23

control valve

24

pestle

25

piston element

26

pivot area

27

cavity

28

outside

29

actuator housing

30a

first mating surface

30b

second mating surface

31

lid

32

outer surface

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited 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.

Patent Literature Cited

• DE 102016118710 A1 [0002]
• EP 1596040 B1 [0002]

Claims (10)

Timing adjustment system (1) for an internal combustion engine (2), having a camshaft (3) and a camshaft adjuster (4) coupled to the camshaft (3), with a stator (10) of the camshaft adjuster (4) on an axial side (5). with the camshaft (3) further coupled support area (7) is arranged, which support area (7) is prepared directly for the axial and/or radial support of the camshaft (3) relative to a component (8) of the internal combustion engine (2) fixed to the housing, thereby characterized in that the camshaft adjuster (4) is connected to the camshaft (3) by means of an anchor element (9) and a rotor (11) of the camshaft adjuster (4) which can be rotated to a limited extent relative to the stator (10) directly on a support area (7) having base body (22) of the anchor element (9) attached or at least partially integrally formed with this base body (22). Timing adjustment system (1) according to claim 1 , characterized in that the support area (7) has at least one axial bearing surface (14, 15) which is in axial contact with the housing-fixed component (8). Timing adjustment system (1) according to claim 1 or 2 , characterized in that the support area (7) has two opposite axial bearing surfaces (14, 15) which are in axial contact with the housing-fixed component (8). Timing adjustment system (1) according to one of Claims 1 until 3 , characterized in that the support area (7) has a radial bearing surface (16) which is in radial contact with the housing-fixed component (8). Timing adjustment system (1) according to one of Claims 1 until 4 , characterized in that an actuator (19) used to control the camshaft adjuster (4) is connected to the component (8) fixed to the housing and is arranged at a distance from the support area (7) or is in direct contact with the support area (7). Timing adjustment system (1) according to one of Claims 1 until 5 , characterized in that the support area (7) has at least one radial collar (17a, 17b) and/or at least one radial recess (20a, 20b). Timing adjustment system (1) according to claim 6 , characterized in that the at least one radial collar (17a, 17b) is formed in one piece with the base body (22) of the anchor element (9). Timing adjustment system (1) according to claim 6 or 7 , characterized in that a radial collar (17a) is formed on a fastening nut (13) screwed to the base body (22) of the anchor element (9). Timing adjustment system (1) according to one of Claims 6 until 8th , characterized in that the support area (7) has two axially spaced radial collars (17a, 17b) which are supported on mutually opposite counter-abutment surfaces (30a, 30b) of the component (8) fixed to the housing. Timing adjustment system (1) according to one of Claims 6 until 9 , characterized in that a supporting web (21a, 21b) of the component (8) fixed to the housing projects into the at least one recess (20a, 20b).

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