DE102020007407A1 - Valve guide element for an internal combustion engine, in particular a motor vehicle, and internal combustion engine - Google Patents

Abstract

The invention relates to a valve guide element (10) for an internal combustion engine, with a through-opening (12) having a hole edge (16, 18) at each of its two ends (E1, E2) for guiding a valve stem of a gas exchange valve of the internal combustion engine, at least one of the hole edges (16, 18) has an embossing (20, 22) at least in a partial area (T).

Description

The invention relates to a valve guide element for an internal combustion engine, in particular a motor vehicle, according to the preamble of patent claim 1. The invention also relates to an internal combustion engine for a motor vehicle.

Such a valve guide element for an internal combustion engine, in particular a motor vehicle, is, for example, already DE 10 2017 010 826 A1 to be taken as known. The valve guide element has a through opening which has a hole edge at each of its two ends. A valve stem of a gas exchange valve of the internal combustion engine can be guided by means of the through opening. In other words, at least one longitudinal area of the valve stem can be arranged in the through-opening and thus penetrate the through-opening and thus the valve guide element, as a result of which the gas exchange valve can be guided via its valve stem by means of the valve guide element, in particular relative to a cylinder head of the internal combustion engine. Furthermore, the DE 10 2019 121 826 A1 a valve guide for guiding a valve stem in a cylinder head of an internal combustion engine.

The object of the present invention is to further develop a valve guide element and an internal combustion engine of the type mentioned at the outset in such a way that a particularly advantageous guidance of a gas exchange valve can be implemented.

This object is achieved by a valve guide element having the features of patent claim 1 and by an internal combustion engine having the features of patent claim 4 . Advantageous configurations with expedient developments of the invention are specified in the remaining claims.

In order to further develop a valve guide element of the type specified in the preamble of claim 1 in such a way that a particularly advantageous operation of guiding the gas exchange valve can be implemented, it is provided according to the invention that at least one of the hole edges has an embossing, i.e. a hole edge embossing, at least in a partial area. In other words, the at least one hole edge is processed by embossing or embossing, at least in the sub-area mentioned.

When new, valve guides in internal combustion engines usually have an at least essentially cylindrical shape. Finishing of the respective valve guide usually takes place in a pressed-in state of the respective valve guide, which in its pressed-in state is pressed into a cylinder head of the internal combustion engine. This means that the valve guide or the valve guide element, also referred to as the valve guide, is formed separately from the cylinder head and is accommodated at least partially, in particular at least predominantly or completely, in the cylinder head, i.e. in a receptacle of the cylinder head, and preferably in the receptacle or in the cylinder head is pressed in. In finishing, for example, a surface of the valve guide is rubbed to a caliper. Conventionally, when manufacturing the valve guide, a valve clearance changes due to wear of a production tool, by means of which the valve guide is manufactured, in particular from a large valve clearance to a small valve clearance.

Against the background described, it is now intended that the valve guide element, also referred to as the valve guide, is basically produced as in the prior art, only that a hole edge embossing tool is then used or is used in order to use the hole edge embossing tool to emboss the at least one hole edge at least in the To emboss sub-area, therefore to be provided with the embossing. The hole edge tool, also referred to simply as an embossing tool, has a calibration mandrel, for example. Thus, the valve clearance can be kept at least almost the same. The embossing tool can be designed in such a way that different dimensions and/or geometries are produced on a combustion chamber side, ie on a combustion chamber end of the through opening and/or on a valve stem seal side, ie on a valve stem seal end of the through opening. The combustion chamber side is a first side of the through opening or of the valve guide element, with the first side facing a combustion chamber of the internal combustion engine in the fully manufactured state of the internal combustion engine, preferably referred to as a reciprocating piston engine or reciprocating piston engine. The valve stem seal side is to be understood as meaning a second side of the through opening or of the valve guide element, the second side facing away from the first side, in particular in the axial direction of the valve guide element. In particular, the second side faces a valve stem seal, by means of which, for example, a valve stem, also simply referred to as a stem, of the gas exchange valve, which is preferably designed as a poppet valve, is held against the cylinder the head and/or is sealed against the valve guide element.

• - Reibleistungsreduzierung
• - schneller Teileeinlauf
• - verbesserter Ölzufluss
• - kleine Fertigungstoleranzen
• - Vermeidung von Ventilklemmen
• - verbesserte Schmierölversorgung ins Lager beziehungsweise in die Ventilführung
• - bessere Wärmeabfuhr durch Ölfilm
• - Reduzierung der thermischen Belastung des Gaswechselventils
• - schneller Einlauf durch Kantenträger
• - Erhöhung einer Dichtfunktion zwischen Gaswechselventil und Ventilführung
• - unterschiedliche Spielauslegungen zwischen Ventilführung oben beziehungsweise unten und Ventilführungseinlass beziehungsweise -auslass möglich

An embossing bead is produced by producing or forming the embossing, in particular by means of the embossing tool. This embossed bead allows a very quick run-in to be enforced, which means that a reduction in friction can be achieved compared to conventional solutions. On the valve stem seal side, for example, an increased bearing gap can be forced or created by interrupting the embossing, also known simply as embossing, particularly on or in unloaded or slightly loaded areas, so that oil transport into the valve guide or into the through-opening is supported. Because of this increased oiling, heat can be dissipated in a particularly advantageous manner, as a result of which the friction can be further reduced. On or on the combustion chamber side, the or an embossing can run completely around the through opening in the circumferential direction of the through opening, thus running 360 degrees in the circumferential direction of the through opening, whereby a particularly good seal to the combustion chamber side can be achieved. In particular, the following advantages can be realized by the invention:

• - Friction reduction
• - faster parts infeed
• - improved oil flow
• - Small manufacturing tolerances
• - Avoidance of valve sticking
• - Improved lubricating oil supply to the bearing or the valve guide
• - Better heat dissipation through oil film
• - Reduction of the thermal load on the gas exchange valve
• - faster run-in thanks to edge carriers
• - Increase of a sealing function between gas exchange valve and valve guide
• - Different clearance designs between the valve guide at the top or bottom and the valve guide inlet or outlet are possible

The invention also includes an internal combustion engine for a motor vehicle, with at least one valve guide element according to the invention. Advantages and advantageous configurations of the valve guide element according to the invention are to be regarded as advantages and advantageous configurations of the internal combustion engine according to the invention and vice versa.

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 and the features and combinations of features mentioned below in the description of the figures and/or shown alone in the figures can be used not only in the combination specified in each case, but also in other combinations or on their own, without going beyond the scope of the leave invention.

• 1 eine schematische Seitenansicht eines erfindungsgemäßen Ventilführungselements für eine Verbrennungskraftmaschine;
• 2 eine schematische Längsschnittansicht des Ventilführungselements;
• 3 eine schematische und vergrößerte Darstellung eines in 2 mit Y bezeichneten Bereichs des Ventilführungselements;
• 4 eine schematische und vergrößerte Darstellung eines in 2 mit Z bezeichneten Bereichs des Ventilführungselements; und
• 5 ausschnittsweise eine schematische Unteransicht des Ventilführungselements;
• 6 eine weitere schematische Längsschnittansicht des Ventilführungselements bei dessen Herstellung mittels eines Lochkantenprägewerkzeugs;
• 7 eine schematische und vergrößerte Darstellung eines in 6 mit X bezeichneten Bereichs.

The drawing shows in:

• 1 a schematic side view of a valve guide element according to the invention for an internal combustion engine;
• 2 a schematic longitudinal sectional view of the valve guide element;
• 3 a schematic and enlarged representation of an in 2 area of the valve guide element marked Y;
• 4 a schematic and enlarged representation of an in 2 designated Z area of the valve guide member; and
• 5 a detail of a schematic bottom view of the valve guide element;
• 6 a further schematic longitudinal sectional view of the valve guide element during its production by means of a hole edge embossing tool;
• 7 a schematic and enlarged representation of an in 6 area marked X.

Elements that are the same or have the same function are provided with the same reference symbols in the figures.

1 shows a schematic side view of a valve guide element 10, also referred to as a valve guide, for an internal combustion engine designed as a reciprocating piston engine or reciprocating piston machine of a motor vehicle, in particular a motor vehicle preferably designed as a passenger car. This means that the motor vehicle can be driven by the internal combustion engine. The internal combustion engine has at least one combustion chamber. At least one gas exchange valve, which can be designed as a poppet valve, is assigned to the combustion chamber. The combustion chamber is partly delimited by a combustion chamber roof and partly by a cylinder. The cylinder is characterized by a crankcase or cylinder crankcase, for example formed cylinder housing of the internal combustion engine formed or limited. The combustion chamber roof is delimited by a cylinder head of the internal combustion engine, the cylinder head of which is designed separately from the cylinder housing and is connected to the cylinder housing. The cylinder head has a receptacle designed, for example, as a through-opening, in which the valve guide element 10 (valve guide) designed separately from the cylinder head is arranged at least partially, in particular at least predominantly or completely. For example, the valve guide is pressed into the mount and thus into the cylinder head.

Especially good in combination with 2 it can be seen that the valve guide element 10 has a through opening 12 which completely penetrates the valve guide in the axial direction of the valve guide. The gas exchange valve, also referred to simply as a valve, has a valve stem, also referred to simply as a stem. In the completely manufactured state of the internal combustion engine, at least one longitudinal area of the valve stem is arranged in the through-opening 12, so that the valve stem penetrates the through-opening 12 and thus the valve guide, in particular completely. The gas exchange valve is movable relative to the cylinder head and thus relative to the valve guide in a translatory manner between a closed position and at least one open position. The gas exchange valve is guided via the valve stem by means of the through opening 12, ie by means of the valve guide element 10, in particular relative to the cylinder head. The axial direction of the valve guide element 10 is in 1 and 2 illustrated by a dot-dash line 14. How particularly good looking 2 As can be seen, the through-opening 12 has a respective hole edge 16 or 18 at its two opposite ends E1 and E2 in the axial direction of the valve guide. While the hole edge is 16 in 3 shown partially and enlarged, the edge of the hole is in 4 shown partially and enlarged.

The end E1 and thus the hole edge 16 are arranged on or on a combustion chamber side S1 of the valve guide and thus the through-opening 12 . In the fully manufactured state of the internal combustion engine, the combustion chamber side S1 faces the combustion chamber. The end E2 and thus the edge of the hole 18 are arranged on or on a valve stem sealing side S2 of the valve guide and the through opening 12 . In the fully manufactured state of the internal combustion engine, the valve stem seal side S2 faces away from the combustion chamber and faces a valve stem seal, by means of which the gas exchange valve, in particular the stem, is sealed against the valve guide element 10 and/or the cylinder head. In addition, the combustion chamber side S1 and the valve stem seal side S2 are also collectively referred to as sides, with the sides facing away from one another in the axial direction of the valve guide.

In order to be able to implement a particularly advantageous guidance of the gas exchange valve by means of the valve guide element 10, the hole edge 16 has a first embossing 20, also referred to as hole edge embossing, which extends in the circumferential direction of the through opening 12 and the valve guide around the axial direction of the valve guide by 360 Degree extends, therefore extends completely around the through-opening 12 around. In addition, the edge of the hole 18 has a respective second embossing 22 in at least or exactly two partial areas T, also referred to as hole edge embossing. The sub-areas T and thus the embossings 22 arranged or running in the sub-areas T are spaced apart from one another in the circumferential direction of the through-opening 12 and thus of the valve guide and arranged one after the other and preferably arranged evenly distributed. The respective partial area T and thus the respective embossing 22 arranged or running in the respective partial area T extend in the circumferential direction of the through-opening 12 and thus of the valve guide over a respective first angular range. It is preferably provided that the first angular ranges, over which the second embossings 22 extend, are the same. In the circumferential direction of the through-opening 12, the respective first angular range and thus the respective second embossing 22 is followed by a respective second angular range in which the hole edge 18 is free of an embossing and thus free of the embossing 22. This means that a respective, second partial area of the hole edge 18 extends over the respective, second angular range, the respective second partial area of the hole edge 18, hence the hole edge 18 in the respective second partial area, being free of an embossing. This also means that the respective second partial areas are arranged in the circumferential direction between the first partial areas T, so that the first partial areas and the second partial areas follow one another alternately in the circumferential direction of the through-opening 12 . Thus, while the edge of the hole 16 is provided with the embossing 20 along its entire extent running in the circumferential direction of the through-opening 12, the edge of the hole 18 is provided with the embossing 22 only locally and is free of an embossing in the second partial areas. In other words, the embossing 20 is a hole edge embossing extending over 360 degrees in the circumferential direction of the through-opening 12. which is arranged on or on the combustion chamber side S1. In this way, a particularly advantageous sealing of or towards the combustion chamber side S1 can be implemented.

For example, the respective, first sub-area T is a loaded area, in particular during operation of the internal combustion engine, while, for example, the respective, second sub-area is a non-loaded or less heavily loaded area during operation. In other words, for example during operation of the internal combustion engine, the respective second partial area is less heavily loaded than the respective first partial area. Thus, the respective embossing 22 is provided in the stressed or more heavily stressed area, while the area (second partial area) that is not or less heavily stressed is not embossed, that is to say is free of an embossing. To put it another way, no embossing or no embossing is provided in the non-loaded or unloaded or less heavily loaded area, that is to say in the respective second partial area. This can ensure a particularly advantageous oil transport into the valve guide.

In 5 one of the second partial areas can be seen and is labeled T2. Engine oil can particularly advantageously flow into the valve guide, in particular via the respective second partial area T2, as a result of which particularly advantageous lubrication can be ensured.

Based on 6 and 7 a production of the valve guide element 10 (valve guide) is illustrated. The respective embossing 20 or 22 is - as in 6 and 7 is illustrated using the example of embossing 22 - produced for example by means of a hole edge embossing tool 24, which is simply referred to as an embossing tool. The stamping tool includes a calibration mandrel 26 so that an excessive change in valve clearance due to wear of a production tool for making the valve guide can be avoided. The valve guide is embossed at the respective end E1 or E2 by means of the embossing tool, that is to say it is machined in an embossing manner, as a result of which the respective embossing 20 or 22 is produced.

Reference List

10

valve guide element

12

passage opening

14

dotted line

16

hole edge

18

hole edge

20

embossing

22

embossing

24

hole edge embossing tool

26

calibration mandrel

E1, E2

End

S1

combustion chamber side

S2

valve stem seal side

T, T2

subarea

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 102017010826 A1 [0002]
• DE 102019121826 A1 [0002]

Claims (4)

Valve guide element (10) for an internal combustion engine, with a through opening (12) having a hole edge (16, 18) at each of its two ends (E1, E2) for guiding a valve stem of a gas exchange valve of the internal combustion engine, characterized in that at least one of the hole edges ( 16, 18) has an embossing (20, 22) at least in a partial area (T). Valve guide element (10) after claim 1 , characterized in that the embossing (20) in the circumferential direction of the through-opening (12) extends completely around the through-opening (12). Valve guide element (10) after claim 1 , characterized in that the embossing (22) extends in the circumferential direction of the through-opening (12) over a first angular range (T), with a second angular range (T2) adjoining the first angular range (T) in the circumferential direction of the through-opening (12). , in which the at least one hole edge (18) is free of an embossing. Internal combustion engine for a motor vehicle, having at least one valve guide element (10) according to one of the preceding claims.

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