EP1722076A1 - Valve drive train for an internal combustion engine - Google Patents

Valve drive train for an internal combustion engine Download PDF

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Publication number
EP1722076A1
EP1722076A1 EP06005932A EP06005932A EP1722076A1 EP 1722076 A1 EP1722076 A1 EP 1722076A1 EP 06005932 A EP06005932 A EP 06005932A EP 06005932 A EP06005932 A EP 06005932A EP 1722076 A1 EP1722076 A1 EP 1722076A1
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EP
European Patent Office
Prior art keywords
valve
gas exchange
internal combustion
combustion engine
support element
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Granted
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EP06005932A
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German (de)
French (fr)
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EP1722076B1 (en
Inventor
Gert Fischer
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Bayerische Motoren Werke AG
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Bayerische Motoren Werke AG
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Publication of EP1722076A1 publication Critical patent/EP1722076A1/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
    • F01L13/0015—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
    • F01L1/12—Transmitting gear between valve drive and valve
    • F01L1/18—Rocking arms or levers
    • F01L1/185—Overhead end-pivot rocking arms
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
    • F01L13/0015—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
    • F01L13/0021—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque by modification of rocker arm ratio

Definitions

  • the invention relates to a valve train for an internal combustion engine with the features of the preamble of patent claim 1.
  • variable valve train for an internal combustion engine to achieve variable valve opening angle at particularly small valve strokes that with the camshaft rotational axis substantially parallel tilting axis of a rocker arm relative to a camshaft along a path controlled so displaced that with displaced tilting axis of the rocker arm only is activated approximately from the initial region to about the end portion of the cam tip of the control cam for valve actuation.
  • the valve drive has an axially displaceable support element, which can be latched in a defined position by a latching element, so that the gas exchange valve has its maximum valve lift. If the valve lift is to be reduced, the support element is unlatched and pressed against a spring element, whereby the valve lift of the gas exchange valve is reduced in the above manner.
  • a disadvantage of the described embodiment is the very complicated to be manufactured adjusting mechanism for the variable stroke valve drive of the internal combustion engine, as well as the high forces acting on the locking mechanism.
  • Object of the present invention is to show a measure of how the structural complexity and at the same time the forces occurring in a generic valve train for Ventilhubsver ein can be significantly reduced.
  • VANOS camshaft turning device
  • the intake gas exchange valves may have different strokes (maximum lift (X) and mini lift (Y)) to increase charge and swirl in the combustion chamber in the medium speed range.
  • the short opening of the mini-lift gas exchange valve ie a valve lift less than 2 mm (Y)
  • a valve lift less than 2 mm (Y) prevents a larger HC output (hydrocarbon discharge), since no fuel can accumulate on it as with a completely closed intake gas changeover valve.
  • the valve train according to the invention requires no special manufacturing tolerances in the mini stroke, since the Hubauf clips the rotating cam very well, the opening and closing time very precise and the mini stroke (Y) is very easy to adjust from the outside when needed, which is especially in idle and idle close range of the engine a good synchronization with low speed fluctuations is achieved.
  • the valve train according to the invention can also be used for Auslassgas crispventile.
  • the lifting height of the gas exchange valve in the mini-lift can be varied within the proposed Minihub Schemes in an advantageous manner.
  • a preferred embodiment of the clearance compensation element is the use of a hydraulic clearance compensation element.
  • the intermediate element is preferably a tilting or drag lever, particularly preferably with a roller.
  • valve train 1 shows a schematic diagram of a valve train 1 according to the invention for a non-illustrated internal combustion engine with a cylinder head 8.
  • the valve train 1 has a camshaft 2 with a cam 2 ', which is in operative connection with a roller 4' of an intermediate element 4.
  • the intermediate element 4 is a drag lever, which may also be a rocker arm in another embodiment.
  • the intermediate element 4 rests on the one hand on a valve stem end 3 'of a gas exchange valve 3 and on the other hand on a support element 6.
  • a spring element 7 is arranged, which presses the support element 6 together with the intermediate element 4 in the direction of the camshaft 2.
  • the support element 6 is held by a fixing device 9 in a defined position. In this position, the gas exchange valve 3 is opened upon actuation of the valve train 1 by the cam 2 'with a maximum stroke (X) against a spring force of a valve spring 5.
  • Fig. 2 in which the same reference numerals apply to the same components as in Fig. 1, the same valve gear for the internal combustion engine is shown again, but with an unlocked support member 6.
  • the support member 6 is now on the stop 10 and the Gas exchange valve 3 has a mini-stroke (Y) of a maximum of 2 mm due to the changed transmission ratio.
  • a very simple, extremely low-cost variability in the valve train 1 can be realized without the relevant mass for high speeds in the valve train 1 increase.
  • the installation space in the cylinder head 8 is neither increased in comparison to a cylinder head without this variability, nor is a noticeable increase in weight ascertainable, since neither additional adjusting motors, additional control shafts or the like are required.
  • a camshaft twisting device VANOS can be combined with the valve drive 1 according to the invention.
  • the opening angles of the intake gas exchange valves required for higher speeds and higher power can be increased to a certain extent.
  • the intake gas exchange valves 3 may also have different strokes, maximum lift (X) and mini lift (Y), in order to increase filling and swirl in the combustion chamber in the middle speed range.
  • X maximum lift
  • Y mini lift
  • the short opening of the mini-lift gas exchange valve prevents a larger HC emissions (hydrocarbon emissions), since no fuel, as in a completely closed inlet gas exchange valve, can attach to this.
  • valve gear 1 according to the invention requires in the Minihub Scheme (Y) no special manufacturing tolerances, since the Hubaufels the rotating cam very well, the opening and closing time very precise and the Minihub (Y) is very easy to adjust from the outside if necessary, which is particularly idle and idle region of the engine good synchronization with low speed fluctuations is achieved.
  • the valve gear 1 according to the invention can also be used for Auslassgas strigventile.
  • the cam 2 ' actuates a gas exchange valve 3, wherein the support member 6 has a fixing device 9, which causes the usual full stroke (X) of the gas exchange valve in the blocked state.
  • the support member 6 takes on the cam lift such that the gas exchange valve 3 initially remains closed.
  • the valve drive 1 runs against a fixed, advantageously also adjustable stop 10, so that the gas exchange valve 3 now has to compulsively open a mini-stroke (Y).
  • a gas exchange valve speed assumes values that move in the ramp range of conventional valve trains and also the mini-stroke (Y) is driven only in the lower speed range.
  • Y mini-stroke
  • no higher opening and closing speeds of the gas exchange valve 3 are achieved than in a conventional valve train.
  • the stop 10 can also be provided with an oil damping.
  • the gas exchange valve speed is plotted against the cam angle.
  • the gas exchange valve speed curve corresponds to an opening of the gas exchange valve 3 for a maximum lift (X).
  • the opening stroke of the gas exchange valve 3 begins in the coordinate 0, 0 with a ramp region, which is predetermined by a contour of the cam 2 ', as used in valve trains without hydraulic clearance compensation.
  • the region of the maximum gas exchange valve speed adjoins the ramp region in accordance with the further gas exchange valve opening stroke.
  • the gas exchange valve speed is reached 0 m / s, after the zero crossing, which is designated with the cam tip, closes the gas exchange valve 3 again.
  • the hatching area shown hatched in which the valve train 1 can be switched to the mini-stroke (Y).
  • a clearance compensation element preferably a hydraulic clearance compensation element is integrated into the support element 6.
  • the position fixing according to the invention can also be used when the valve train has no intermediate element.
  • An example of this is a valve train with a valve cup, which below the bottom to the valve stem an element, for example, instead of a hydraulic clearance compensation element includes, having a corresponding locking device.
  • the operation of the locking device is somewhat more difficult, the oscillating mass increases slightly and the space is increased easily, in this embodiment, the intermediate element 4 and the supporting element 6 would be represented together by the valve cup.

Abstract

The valve drive (1) has a camshaft (2) and a stopper (10). The stopper is provided for the supporting element (6) with that the unfixed supporting element is fixed in the second position, correspondingly a valve lift of the gas exchange valve (3) is smaller than 2 mm. An independent claim is also included for internal combustion engine.

Description

Die Erfindung betrifft einen Ventiltrieb für eine Brennkraftmaschine mit den Merkmalen aus dem Oberbegriff des Patentanspruchs 1.The invention relates to a valve train for an internal combustion engine with the features of the preamble of patent claim 1.

Sie geht von der deutschen Offenlegungsschrift DE 198 25 308 A1 aus. In dieser wird für einen variablen Ventiltrieb für eine Brennkraftmaschine zur Erzielung variabler Ventilöffnungswinkel bei besonders kleinen Ventilhüben vorgeschlagen, dass die mit der Nockenwellendrehachse im wesentlichen parallele Kippachse eines Kipphebels relativ zu einer Nockenwelle längs einer Bahn derart gesteuert verlagerbar ist, dass mit verlagerter Kippachse der Kipphebel lediglich etwa vom Anfangsbereich bis etwa zum Endbereich der Nockenspitze des Steuernockens zur Ventilbetätigung aktiviert ist. Um dies zu bewerkstelligen verfügt der Ventiltrieb über ein axial verschiebbares Stützelement, welches in einer definierten Lage von einem Rastelement verrastbar ist, so dass das Gaswechselventil seinen maximalen Ventilhub aufweist. Soll der Ventilhub verkleinert werden, wird das Abstützelement entrastet und gegen ein Federelement gedrückt, wodurch der Ventilhub des Gaswechselventils in o. g. Weise reduziert wird.She goes from the German Offenlegungsschrift DE 198 25 308 A1 out. In this is proposed for a variable valve train for an internal combustion engine to achieve variable valve opening angle at particularly small valve strokes that with the camshaft rotational axis substantially parallel tilting axis of a rocker arm relative to a camshaft along a path controlled so displaced that with displaced tilting axis of the rocker arm only is activated approximately from the initial region to about the end portion of the cam tip of the control cam for valve actuation. To accomplish this, the valve drive has an axially displaceable support element, which can be latched in a defined position by a latching element, so that the gas exchange valve has its maximum valve lift. If the valve lift is to be reduced, the support element is unlatched and pressed against a spring element, whereby the valve lift of the gas exchange valve is reduced in the above manner.

Nachteilig bei der beschriebenen Ausgestaltung ist der sehr aufwendig zu fertigende Verstellmechanismus für den hubvariablen Ventiltrieb der Brennkraftmaschine, sowie die hohen Kräfte, die auf den Rastmechanismus einwirken.A disadvantage of the described embodiment is the very complicated to be manufactured adjusting mechanism for the variable stroke valve drive of the internal combustion engine, as well as the high forces acting on the locking mechanism.

Aufgabe der vorliegenden Erfindung ist es eine Maßnahme aufzuzeigen, wie der bauliche Aufwand für und gleichzeitig die auftretenden Kräfte in einem gattungsgemäßen Ventiltrieb zur Ventilhubsverstellung deutlich reduziert werden können.Object of the present invention is to show a measure of how the structural complexity and at the same time the forces occurring in a generic valve train for Ventilhubsverstellung can be significantly reduced.

Diese Aufgabe wird durch das Merkmal im kennzeichnenden Teil des Patentanspruchs 1 dadurch gelöst, dass ein Anschlag für das Abstützelement vorgesehen ist, mit dem das unfixierte Abstützelement in einer zweiten Lage lagefixierbar ist, entsprechend einem Ventilhub des Gaswechselventils kleiner als 2 mm, d. h. für eine geringe Last und Drehzahl der Brennkraftmaschine.
Bei geeigneter Wahl des zwischen dem Nocken und dem Gaswechselventil angeordneten Zwischenelementes, welches gemäß Patentanspruch 6 ein Kipp- oder Schlepphebel bzw. ein Rollenkipp- oder ein Rollenschlepphebel ist, lässt sich eine sehr einfache, extrem kostengünstige Variabilität im Ventiltrieb realisieren, ohne die für hohe Drehzahlen relevante Masse zu erhöhen. Der Bauraum im Zylinderkopf wird im Vergleich zu einem Zylinderkopf ohne diese Variabilität weder vergrößert, noch ist eine spürbare Gewichtszunahme feststellbar, da weder zusätzliche Verstellmotoren, noch Steuerwellen oder dgl. benötigt werden. Bei Bedarf kann eine Nockenwellenverdreheinrichtung (VANOS) mit dem vorgeschlagenen Ventiltrieb kombiniert werden. Da die im unteren Drehzahlbereich schädlichen Ventilöffnungsüberschneidungen von Einlass- und Auslassgaswechselventil vermieden werden (bei externer Gemischaufbereitung, d. h. Saugrohreinspritzung), können die für höhere Drehzahlen und höhere Leistung erforderlichen Öffnungswinkel der Gaswechselventile in einem gewissen Rahmen vergrößert werden. Bei 4-Ventil-Brennkraftmaschinen können die Einlassgaswechselventile unterschiedliche Hübe aufweisen (Maximalhub (X) und Minihub (Y)), um im mittleren Drehzahlbereich Füllung und Drall im Brennraum zu erhöhen. Das kurze Öffnen des Minihub-Gaswechselventils, d. h. ein Ventilhub kleiner 2 mm (Y), verhindert hierbei einen größeren HC-Ausstoß (Kohlenwasserstoffausstoß), da sich kein Kraftstoff wie bei einem gänzlich geschlossenen Einlassgaswechselventil an diesem anlagern kann. Der erfindungsgemäße Ventiltrieb erfordert im Minihubbereich keine sonderlichen Fertigungstoleranzen, da die Hubauflösung des umlaufenden Nockens sehr gut, der Öffnungs- und Schließzeitpunkt sehr präzise und der Minihub (Y) bei Bedarf sehr einfach von außen einstellbar ist, womit besonders im Leerlauf und leerlaufnahem Bereich der Brennkraftmaschine ein guter Gleichlauf mit geringen Drehzahlschwankungen erzielt wird. Selbstverständlich kann der erfindungsgemäße Ventiltrieb auch für Auslassgaswechselventile verwendet werden.This object is achieved by the feature in the characterizing part of patent claim 1, characterized in that a stop for the support element is provided, with which the unfixed support element is positionally fixed in a second position, corresponding to a valve lift of the gas exchange valve smaller than 2 mm, ie for a small Load and speed of the internal combustion engine.
With a suitable choice of the arranged between the cam and the gas exchange valve intermediate element, which is a tilt or rocker arm or a Rollenkipp- or a roller rocker arm according to claim 6, can be a very simple, extremely low-cost variability in the valve train realize without the high speeds increase relevant mass. The space in the cylinder head is compared to a cylinder head without this variability neither increased, nor is a noticeable increase in weight determined, since neither additional adjusting motors, control shafts or the like. Needed. If necessary, a camshaft turning device (VANOS) can be combined with the proposed valve train. Since the valve opening overlaps damaging the intake and exhaust gas exchange valve in the lower speed range are avoided (with external mixture preparation, ie intake manifold injection), the opening angle of the gas exchange valves required for higher speeds and higher power can be increased to a certain extent. For 4-valve internal combustion engines For example, the intake gas exchange valves may have different strokes (maximum lift (X) and mini lift (Y)) to increase charge and swirl in the combustion chamber in the medium speed range. The short opening of the mini-lift gas exchange valve, ie a valve lift less than 2 mm (Y), prevents a larger HC output (hydrocarbon discharge), since no fuel can accumulate on it as with a completely closed intake gas changeover valve. The valve train according to the invention requires no special manufacturing tolerances in the mini stroke, since the Hubauflösung the rotating cam very well, the opening and closing time very precise and the mini stroke (Y) is very easy to adjust from the outside when needed, which is especially in idle and idle close range of the engine a good synchronization with low speed fluctuations is achieved. Of course, the valve train according to the invention can also be used for Auslassgaswechselventile.

Durch die Ausgestaltung gemäß Patentanspruch 2 kann in vorteilhafter Weise die Hubhöhe des Gaswechselventils im Minihubbereich zusätzlich innerhalb des vorgeschlagenen Minihubbereichs variiert werden.Due to the configuration according to claim 2, the lifting height of the gas exchange valve in the mini-lift can be varied within the proposed Minihubbereichs in an advantageous manner.

Durch die Ausgestaltung gemäß der Patentansprüche 3 und 4 wird ein spielfreier Ventiltrieb erzielt.Due to the configuration according to claims 3 and 4, a play-free valve train is achieved.

Eine bevorzugte Ausführungsvariante des Spielausgleichselementes ist die Verwendung eines hydraulischen Spielausgleichselementes.A preferred embodiment of the clearance compensation element is the use of a hydraulic clearance compensation element.

Wie bereits unter den vorteilhaften Wirkungen von Patentanspruch 1 ausgeführt, ist das Zwischenelement vorzugsweise ein Kipp- oder Schlepphebel, besonders bevorzugt mit einer Rolle.As already stated under the advantageous effects of claim 1, the intermediate element is preferably a tilting or drag lever, particularly preferably with a roller.

Im Folgenden ist die Erfindung anhand eines bevorzugten Ausführungsbeispieles in drei Figuren näher erläutert.

Fig. 1
zeigt in einer Schemazeichnung das Funktionsprinzip eines erfindungsgemäßen Ventiltriebes bei einem maximalen Gaswechselventilhub;
Fig. 2
zeigt die gleiche Schemazeichnung wie Fig. 1, jedoch für einen Minihub des Gaswechselventils;
Fig. 3
zeigt in einem Diagramm eine Gaswechselventilgeschwindigkeit über einem Nockenwinkel aufgetragen.
The invention is explained in more detail below with reference to a preferred embodiment in three figures.
Fig. 1
shows a schematic diagram of the principle of operation of a valve train according to the invention at a maximum Gaswechselventilhub;
Fig. 2
shows the same schematic drawing as Figure 1, but for a mini-stroke of the gas exchange valve.
Fig. 3
shows in a diagram a gas exchange valve speed plotted against a cam angle.

Fig. 1 zeigt eine Schemazeichnung eines erfindungsgemäßen Ventiltriebs 1 für eine nicht näher dargestellte Brennkraftmaschine mit einem Zylinderkopf 8. Der Ventiltrieb 1 weist eine Nockenwelle 2 mit einem Nocken 2' auf, der mit einer Rolle 4' eines Zwischenelementes 4 in Wirkverbindung steht. Im vorliegenden Ausführungsbeispiel ist das Zwischenelement 4 ein Schlepphebel, der in einem anderen Ausführungsbeispiel auch ein Kipphebel sein kann. Das Zwischenelement 4 liegt einerseits auf einem Ventilschaftende 3' eines Gaswechselventils 3 und andererseits auf einem Abstützelement 6 auf. Zwischen dem Zylinderkopf 8 und dem Abstützelement 6 ist ein Federelement 7 angeordnet, welches das Abstützelement 6 mitsamt dem Zwischenelement 4 in Richtung Nockenwelle 2 drückt. Das Abstützelement 6 wird von einer Fixiervorrichtung 9 in einer definierten Lage gehalten. In dieser Lage wird das Gaswechselventil 3 bei Betätigung des Ventiltriebes 1 von dem Nocken 2' mit einem Maximalhub (X) gegen eine Federkraft einer Ventilfeder 5 geöffnet.1 shows a schematic diagram of a valve train 1 according to the invention for a non-illustrated internal combustion engine with a cylinder head 8. The valve train 1 has a camshaft 2 with a cam 2 ', which is in operative connection with a roller 4' of an intermediate element 4. In the present embodiment, the intermediate element 4 is a drag lever, which may also be a rocker arm in another embodiment. The intermediate element 4 rests on the one hand on a valve stem end 3 'of a gas exchange valve 3 and on the other hand on a support element 6. Between the cylinder head 8 and the support element 6, a spring element 7 is arranged, which presses the support element 6 together with the intermediate element 4 in the direction of the camshaft 2. The support element 6 is held by a fixing device 9 in a defined position. In this position, the gas exchange valve 3 is opened upon actuation of the valve train 1 by the cam 2 'with a maximum stroke (X) against a spring force of a valve spring 5.

Bei einer Entriegelung des Abstützelementes 6 durch die Fixiervorrichtung 9 drückt der Nocken 2' das Zwischenelement 4 beim Betrieb der Brennkraftmaschine abstützelementseitig in Richtung Zylinderkopf gegen die Federkraft des Federelementes 7 weg, da die Federkraft der Ventilfeder 5 größer als die Federkraft des Federelementes 7 ist. Das Abstützelement 6 sackt hierbei so weit in Richtung Zylinderkopf 8 ab, bis es auf einem Anschlag 10 aufliegt. Durch das Niederdrücken des entriegelten Abstützelementes 6, wird das Übersetzungsverhältnis im Ventiltrieb 1 verändert, wodurch - wie in Fig. 2 dargestellt - nur noch ein Minihub (Y), kleiner 2 mm, von dem Gaswechselventil 3 durchgeführt wird.With an unlocking of the support element 6 by the fixing device 9, the cam 2 'pushes the intermediate element 4 during operation of the internal combustion engine abstützelementseitig in the direction of the cylinder head against the spring force of the spring element 7, since the spring force of the valve spring 5 is greater than the spring force of the spring element 7. The support element 6 sags in this case far in the direction of the cylinder head 8, until it rests on a stop 10. By depressing the unlocked support member 6, the gear ratio is changed in the valve train 1, whereby - as shown in Fig. 2 - only a mini lift (Y), less than 2 mm, is performed by the gas exchange valve 3.

In Fig. 2, in der die gleichen Bezugszeichen für die gleichen Bauelemente wie in Fig. 1 gelten, ist der gleiche Ventiltrieb für die Brennkraftmaschine nochmals dargestellt, jedoch mit einem entriegelten Abstützelement 6. Das Abstützelement 6 liegt nun auf dem Anschlag 10 auf und das Gaswechselventil 3 hat aufgrund des geänderten Übersetzungsverhältnisses einen Minihub (Y) von maximal 2 mm.In Fig. 2, in which the same reference numerals apply to the same components as in Fig. 1, the same valve gear for the internal combustion engine is shown again, but with an unlocked support member 6. The support member 6 is now on the stop 10 and the Gas exchange valve 3 has a mini-stroke (Y) of a maximum of 2 mm due to the changed transmission ratio.

Bei geeigneter Wahl des zwischen dem Nocken 2' und dem Gaswechselventil 3 angeordneten Zwischenelementes 4, welches im vorliegenden Ausführungsbeispiel ein Rollenschlepphebel ist, lässt sich eine sehr einfache, extrem kostengünstige Variabilität im Ventiltrieb 1 realisieren, ohne die für hohe Drehzahlen relevante Masse im Ventiltrieb 1 zu erhöhen. Der Bauraum im Zylinderkopf 8 wird im Vergleich zu einem Zylinderkopf ohne diese Variabilität weder vergrößert, noch ist eine spürbare Gewichtszunahme feststellbar, da weder zusätzliche Verstellmotoren, zusätzliche Steuerwellen oder dgl. benötigt werden. Bei Bedarf kann eine Nockenwellenverdreheinrichtung (VANOS) mit dem erfindungsgemäßen Ventiltrieb 1 kombiniert werden. Da die im unteren Drehzahlbereich schädlichen Gaswechselventilöffnungsüberschneidungen vermieden werden, (bei externer Gemischaufbereitung, d. h. Saugrohreinspritzung), können die für höhere Drehzahlen und höhere Leistung erforderlichen Öffnungswinkel der Einlassgaswechselventile in einem gewissen Rahmen vergrößert werden. Bei 4-Ventil-Brennkraftmaschinen können die Einlassgaswechselventile 3 auch unterschiedliche Hübe, Maximalhub (X) und Minihub (Y), aufweisen, um im mittleren Drehzahlbereich Füllung und Drall im Brennraum zu erhöhen. Das kurze Öffnen des Minihub-Gaswechselventils verhindert hierbei einen größeren HC-Ausstoß (Kohlenwasserstoffausstoß), da sich kein Kraftstoff, wie bei einem gänzlich geschlossenen Einlassgaswechselventil, an diesem anlagern kann. Der erfindungsgemäße Ventiltrieb 1 erfordert im Minihubbereich (Y) keine sonderlichen Fertigungstoleranzen, da die Hubauflösung des umlaufenden Nockens sehr gut, der Öffnungs- und Schließzeitpunkt sehr präzise und der Minihub (Y) bei Bedarf sehr einfach von außen einstellbar ist, womit besonders im Leerlauf und leerlaufnahen Bereich der Brennkraftmaschine ein guter Gleichlauf mit geringen Drehzahlschwankungen erzielt wird. Selbstverständlich kann der erfindungsgemäße Ventiltrieb 1 auch für Auslassgaswechselventile verwendet werden.With a suitable choice of between the cam 2 'and the gas exchange valve 3 arranged intermediate element 4, which is a Rollenschlepphebel in the present embodiment, a very simple, extremely low-cost variability in the valve train 1 can be realized without the relevant mass for high speeds in the valve train 1 increase. The installation space in the cylinder head 8 is neither increased in comparison to a cylinder head without this variability, nor is a noticeable increase in weight ascertainable, since neither additional adjusting motors, additional control shafts or the like are required. If necessary, a camshaft twisting device (VANOS) can be combined with the valve drive 1 according to the invention. Since the gas exchange valve opening overlaps which are detrimental in the lower speed range are avoided (with external mixture preparation, ie intake manifold injection), the opening angles of the intake gas exchange valves required for higher speeds and higher power can be increased to a certain extent. In 4-valve internal combustion engines, the intake gas exchange valves 3 may also have different strokes, maximum lift (X) and mini lift (Y), in order to increase filling and swirl in the combustion chamber in the middle speed range. The short opening of the mini-lift gas exchange valve prevents a larger HC emissions (hydrocarbon emissions), since no fuel, as in a completely closed inlet gas exchange valve, can attach to this. The valve gear 1 according to the invention requires in the Minihubbereich (Y) no special manufacturing tolerances, since the Hubauflösung the rotating cam very well, the opening and closing time very precise and the Minihub (Y) is very easy to adjust from the outside if necessary, which is particularly idle and idle region of the engine good synchronization with low speed fluctuations is achieved. Of course, the valve gear 1 according to the invention can also be used for Auslassgaswechselventile.

Beim Betrieb der Brennkraftmaschine liegt der Hauptvorteil darin, dass der Nocken 2' ein Gaswechselventil 3 betätigt, wobei das Abstützelement 6 eine Fixiervorrichtung 9 aufweist, die im blockierten Zustand den üblichen Vollhub (X) des Gaswechselventils bewirkt. Beim Entriegeln des Abstützelementes 6 durch die Fixiervorrichtung 9 nimmt das Abstützelement 6 den Nockenhub derart auf, dass das Gaswechselventil 3 zunächst geschlossen bleibt. In einem Spitzenbereich des Nockens 2' läuft der Ventiltrieb 1 gegen einen festen, vorteilhaft auch einstellbaren Anschlag 10, so dass das Gaswechselventil 3 nun zwanghaft einen Minihub (Y) öffnen muss. Dieser Vorgang ist ohne akustische oder mechanische Nachteile möglich, da im Spitzenbereich des Nockens 2' eine Gaswechselventilgeschwindigkeit Werte annimmt, die sich im Rampenbereich herkömmlicher Ventiltriebe bewegen und außerdem der Minihub (Y) nur im unteren Drehzahlbereich gefahren wird. Absolut gesehen werden keine höheren Öffnungs- und Schließgeschwindigkeiten des Gaswechselventils 3 erreicht als in einem konventionellen Ventiltrieb. Besonders bevorzugt kann der Anschlag 10 auch mit einer Öldämpfung versehen werden.When operating the internal combustion engine, the main advantage is that the cam 2 'actuates a gas exchange valve 3, wherein the support member 6 has a fixing device 9, which causes the usual full stroke (X) of the gas exchange valve in the blocked state. When unlocking the support element 6 by the fixing device 9, the support member 6 takes on the cam lift such that the gas exchange valve 3 initially remains closed. In a tip region of the cam 2 ', the valve drive 1 runs against a fixed, advantageously also adjustable stop 10, so that the gas exchange valve 3 now has to compulsively open a mini-stroke (Y). This process is possible without acoustic or mechanical disadvantages, since in the tip region of the cam 2 ', a gas exchange valve speed assumes values that move in the ramp range of conventional valve trains and also the mini-stroke (Y) is driven only in the lower speed range. In absolute terms, no higher opening and closing speeds of the gas exchange valve 3 are achieved than in a conventional valve train. Particularly preferably, the stop 10 can also be provided with an oil damping.

Um einen Umschaltbereich 11 auf einen Minihub (Y), kleiner 2 mm aufzuzeigen, ist in Fig. 3 die Gaswechselventilgeschwindigkeit über dem Nockenwinkel aufgetragen. Der Gaswechselventilgeschwindigkeitsverlauf entspricht einer Öffnung des Gaswechselventils 3 für einen maximalen Hub (X). Der Öffnungshub des Gaswechselventils 3 beginnt in der Koordinate 0, 0 mit einem Rampenbereich, der durch eine Kontur des Nockens 2' vorgegeben ist, wie sie bei Ventiltrieben ohne hydraulischen Spielausgleich verwendet wird. An den Rampenbereich schließt sich der Bereich der maximalen Gaswechselventilgeschwindigkeit an, entsprechend dem weiteren Gaswechselventilöffnungshub. An der Nockenspitze des Nockens 2' wird die Gaswechselventilgeschwindigkeit 0 m/s erreicht, nach dem Nulldurchgang, der mit Nockenspitze bezeichnet ist, schließt das Gaswechselventil 3 wieder. Im Bereich des Nulldurchgangs der Gaswechselventilgeschwindigkeit liegt der schraffiert dargestellte Umschaltbereich 11, in dem der Ventiltrieb 1 auf den Minihub (Y) umgeschaltet werden kann.In order to show a switching range 11 to a mini-stroke (Y), smaller than 2 mm, in FIG. 3 the gas exchange valve speed is plotted against the cam angle. The gas exchange valve speed curve corresponds to an opening of the gas exchange valve 3 for a maximum lift (X). The opening stroke of the gas exchange valve 3 begins in the coordinate 0, 0 with a ramp region, which is predetermined by a contour of the cam 2 ', as used in valve trains without hydraulic clearance compensation. The region of the maximum gas exchange valve speed adjoins the ramp region in accordance with the further gas exchange valve opening stroke. At the cam tip of the cam 2 ', the gas exchange valve speed is reached 0 m / s, after the zero crossing, which is designated with the cam tip, closes the gas exchange valve 3 again. In the area of the zero crossing of the gas exchange valve speed is the hatching area shown hatched, in which the valve train 1 can be switched to the mini-stroke (Y).

In weiteren besonders bevorzugten Ausführungsbeispielen ist in das Abstützelement 6 ein Spielausgleichselement, vorzugsweise ein hydraulisches Spielausgleichselement integriert.In further particularly preferred embodiments, a clearance compensation element, preferably a hydraulic clearance compensation element is integrated into the support element 6.

Grundsätzlich kann die erfindungsgemäße Lagefixierung auch dann zum Einsatz kommen, wenn der Ventiltrieb kein Zwischenelement aufweist. Ein Beispiel hierfür ist ein Ventiltrieb mit einer Ventiltasse, die unterhalb des Bodens bis zum Ventilschaft ein Element, beispielsweise an Stelle eines hydraulischen Spielausgleichselementes, beinhaltet, das eine entsprechende Rastvorrichtung aufweist. Die Betätigung der Rastvorrichtung ist jedoch etwas schwieriger, die oszillierende Masse etwas erhöht und der Bauraum ieicht vergrößert, in diesem Ausführungsbeispiel wären das Zwischenelement 4 und das Abstützelement 6 gemeinsam durch die Ventiltasse dargestellt.In principle, the position fixing according to the invention can also be used when the valve train has no intermediate element. An example of this is a valve train with a valve cup, which below the bottom to the valve stem an element, for example, instead of a hydraulic clearance compensation element includes, having a corresponding locking device. However, the operation of the locking device is somewhat more difficult, the oscillating mass increases slightly and the space is increased easily, in this embodiment, the intermediate element 4 and the supporting element 6 would be represented together by the valve cup.

BezugszeichenlisteLIST OF REFERENCE NUMBERS

1.1.
Ventiltriebvalve train
2.Second
Nockenwellecamshaft
2'2 '
Nockecam
3.Third
GaswechselventilGas exchange valve
3'3 '
VentilschaftendeValve stem end
4.4th
Zwischenelementintermediate element
4'4 '
Rollerole
5.5th
Ventilfedervalve spring
6.6th
Abstützelementsupporting
7.7th
Federelementspring element
8.8th.
Zylinderkopfcylinder head
9.9th
Fixiervorrichtungfixing
10.10th
Anschlagattack
11.11th
UmschaltbereichSwitching Range

Claims (6)

Ventiltrieb (1) für eine Brennkraftmaschine mit einer Nockenwelle (2) deren Nocke (2') ein Gaswechselventil (3) mittelbar über ein Zwischenelement (4) gegen eine Federkraft einer Ventilfeder (5) betätigt, wobei das Zwischenelement (4) auf einem Ventilschaftende (3') des Gaswechselventils (3) sowie auf einem Abstützelement (6) abgestützt ist, wobei das Abstützelement (6) über eine Federkraft eines Federelementes (7) gegenüber einem Zylinderkopf (8) abgestützt ist und wobei die Federkraft des Federelementes (7) kleiner als die Federkraft der Ventilfeder (5) ist und wobei eine Fixiervorrichtung (9) vorgesehen ist, mit der das Abstützelement (6) in einer ersten Lage, entsprechend einem maximalen Ventilhub (X) des Gaswechselventils (3), lagefixierbar ist,
dadurch gekennzeichnet, dass ein Anschlag (10) für das Abstützelement (6) vorgesehen ist, mit dem das unfixierte Abstützelement (6) in einer zweiten Lage iagefixierbar ist, entsprechend einem Ventilhub (Y) des Gaswechselventils (3) kleiner als 2 mm.Valve train (1) for an internal combustion engine with a camshaft (2) whose cam (2 ') actuates a gas exchange valve (3) indirectly via an intermediate element (4) against a spring force of a valve spring (5), wherein the intermediate element (4) on a valve stem end (3 ') of the gas exchange valve (3) and on a support element (6) is supported, wherein the support element (6) via a spring force of a spring element (7) relative to a cylinder head (8) is supported and wherein the spring force of the spring element (7) is smaller than the spring force of the valve spring (5) and wherein a fixing device (9) is provided with which the support element (6) in a first position, corresponding to a maximum valve lift (X) of the gas exchange valve (3), is fixed in position,
characterized in that a stop (10) for the support element (6) is provided, with which the unfixed support element (6) is fixable in a second position, corresponding to a valve lift (Y) of the gas exchange valve (3) smaller than 2 mm. Spielausgleichselement nach Patentanspruch 1,
dadurch gekennzeichnet, dass die Lage des Anschlags (10) in axialer Richtung des Abstützelementes (6) veränderbar ist.Play compensation element according to claim 1,
characterized in that the position of the stop (10) in the axial direction of the support element (6) is variable. Brennkraftmaschine nach Patentanspruch 1 oder 2,
dadurch gekennzeichnet, dass in das Abstützelement (6) ein Spielausgleichselement integriert ist.Internal combustion engine according to claim 1 or 2,
characterized in that in the support element (6) has a clearance compensation element is integrated. Brennkraftmaschine nach Patentanspruch 1 oder 2,
dadurch gekennzeichnet, dass das Abstützelement (6) als Spielausgleichselement ausgebildet ist.Internal combustion engine according to claim 1 or 2,
characterized in that the support element (6) is designed as a clearance compensation element. Brennkraftmaschine nach Patentanspruch 3 oder 4,
dadurch gekennzeichnet, dass das Spielausgleichselement ein hydraulisches Spielausgleichselement ist.Internal combustion engine according to claim 3 or 4,
characterized in that the clearance compensation element is a hydraulic clearance compensation element. Brennkraftmaschine nach einem der Patentansprüche 1 bis 5,
dadurch gekennzeichnet, dass das Zwischenelement (4) ein Kipp- oder Schlepphebel ist.Internal combustion engine according to one of claims 1 to 5,
characterized in that the intermediate element (4) is a tilting or drag lever.
EP20060005932 2005-05-03 2006-03-23 Valve drive train for an internal combustion engine Active EP1722076B1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE200510020586 DE102005020586A1 (en) 2005-05-03 2005-05-03 Valve drive for internal combustion engine has stopper which is provided for supporting element with that unfixed supporting element is fixed in second position

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EP1722076A1 true EP1722076A1 (en) 2006-11-15
EP1722076B1 EP1722076B1 (en) 2008-05-07

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DE102014201083A1 (en) * 2014-01-22 2015-07-23 Bayerische Motoren Werke Aktiengesellschaft Variably changing a valve opening time of a charge exchange valve

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4134657A1 (en) * 1991-10-19 1992-09-17 Daimler Benz Ag Valve closing motion damper for IC engine - consists of braking cylinder, formed in cylinder head housing, and whose piston acts against valve end of rocker lever
DE4211631A1 (en) * 1992-04-07 1993-04-08 Bayerische Motoren Werke Ag Valve drive with play compensation - has movement path limitation of slide, resulting in valve lift
DE19825308A1 (en) 1998-06-05 1999-12-09 Bayerische Motoren Werke Ag Variable valve train for an internal combustion engine
EP0980965A2 (en) * 1998-08-17 2000-02-23 Dr.Ing. h.c.F. Porsche Aktiengesellschaft Working method for an engine with 2 cylinder groups, and valve drive in an engine with 2 cylinder groups
EP1462623A1 (en) * 2003-03-19 2004-09-29 Eaton Corporation Valve control system permitting dual valve lift and valve deactivation
US20040226524A1 (en) * 2003-05-16 2004-11-18 Hayman Alan W. Direct acting differential two-step valve train

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53123310U (en) * 1977-03-09 1978-09-30
DE4318293A1 (en) * 1992-06-13 1993-12-16 Volkswagen Ag Drag lever for IC engine poppet valve - combines two pistons longitudinally displaceable between lever and working chamber
DE4323555A1 (en) * 1993-07-14 1995-01-19 Bayerische Motoren Werke Ag Device for decommissioning an internal combustion engine lift valve
DE69513165T2 (en) * 1994-05-03 2000-06-15 Lotus Car VALVE DRIVE DEVICE
GB9612178D0 (en) * 1996-06-11 1996-08-14 Ricardo Consulating Engineers Hydraulic tappets
EP1493902A1 (en) * 2003-06-30 2005-01-05 Ford Global Technologies, LLC, A subsidary of Ford Motor Company Device for switching off a valve

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4134657A1 (en) * 1991-10-19 1992-09-17 Daimler Benz Ag Valve closing motion damper for IC engine - consists of braking cylinder, formed in cylinder head housing, and whose piston acts against valve end of rocker lever
DE4211631A1 (en) * 1992-04-07 1993-04-08 Bayerische Motoren Werke Ag Valve drive with play compensation - has movement path limitation of slide, resulting in valve lift
DE19825308A1 (en) 1998-06-05 1999-12-09 Bayerische Motoren Werke Ag Variable valve train for an internal combustion engine
EP0980965A2 (en) * 1998-08-17 2000-02-23 Dr.Ing. h.c.F. Porsche Aktiengesellschaft Working method for an engine with 2 cylinder groups, and valve drive in an engine with 2 cylinder groups
EP1462623A1 (en) * 2003-03-19 2004-09-29 Eaton Corporation Valve control system permitting dual valve lift and valve deactivation
US20040226524A1 (en) * 2003-05-16 2004-11-18 Hayman Alan W. Direct acting differential two-step valve train

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DE102005020586A1 (en) 2006-11-09
DE502006000726D1 (en) 2008-06-19

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