EP1716318B1 - Variable stroke valve drive for an internal combustion engine - Google Patents

Variable stroke valve drive for an internal combustion engine Download PDF

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Publication number
EP1716318B1
EP1716318B1 EP05700827A EP05700827A EP1716318B1 EP 1716318 B1 EP1716318 B1 EP 1716318B1 EP 05700827 A EP05700827 A EP 05700827A EP 05700827 A EP05700827 A EP 05700827A EP 1716318 B1 EP1716318 B1 EP 1716318B1
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EP
European Patent Office
Prior art keywords
valve drive
variable
stroke valve
stroke
drive according
Prior art date
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Active
Application number
EP05700827A
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German (de)
French (fr)
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EP1716318A1 (en
Inventor
Michael Schleusener
Ulrich Gutzer
Christian Flenker
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Bayerische Motoren Werke AG
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Bayerische Motoren Werke AG
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Publication of EP1716318A1 publication Critical patent/EP1716318A1/en
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Classifications

    • 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
    • F01L13/0063—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 cam contact point by displacing an intermediate lever or wedge-shaped intermediate element, e.g. Tourtelot
    • 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
    • F01L13/0026—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 by means of an eccentric
    • 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
    • F01L1/02—Valve drive
    • F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
    • F01L1/08—Shape of cams
    • 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
    • F01L13/0005—Deactivating valves
    • 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
    • F01L13/0063—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 cam contact point by displacing an intermediate lever or wedge-shaped intermediate element, e.g. Tourtelot
    • F01L2013/0068—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 cam contact point by displacing an intermediate lever or wedge-shaped intermediate element, e.g. Tourtelot with an oscillating cam acting on the valve of the "BMW-Valvetronic" type
    • 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
    • F01L2303/00—Manufacturing of components used in valve arrangements
    • F01L2303/01—Tools for producing, mounting or adjusting, e.g. some part of the distribution
    • 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
    • F01L2305/00—Valve arrangements comprising rollers
    • 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
    • F01L2800/00—Methods of operation using a variable valve timing mechanism
    • F01L2800/13—Throttleless
    • 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
    • F01L2810/00—Arrangements solving specific problems in relation with valve gears
    • F01L2810/02—Lubrication
    • 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
    • F01L2820/00—Details on specific features characterising valve gear arrangements
    • F01L2820/03—Auxiliary actuators
    • F01L2820/032—Electric motors

Definitions

  • the invention relates to a variable-stroke valve drive for an internal combustion engine with the features of the preamble of claim 1.
  • the mechanical control has a camshaft, with which the intermediate lever is rotated against the spring force of a return spring to a point close to the stage, so that the shares between Nullhubkurve and lift curve, which are in operative connection with the intermediate element moved.
  • the mechanical control has a second adjusting element, an eccentric shaft, which acts on the intermediate lever near the stage. By rotating the eccentric shaft of the intermediate lever is moved in the backdrop parallel to the slide track, whereby the effective proportion between the lift curve and Leerhubkurve is changed. The proportion of the lift curve with respect to the cam lobe can thus be increased or decreased.
  • An increase in the Hubkurvenanteils corresponds to an increase in Gas monventilhubes.
  • a reduction of the Hubkurvenanteils corresponds to a reduction of Gas monventilhubes until, as described above, only the Leerhubkurvenanteil is in operative connection with the intermediate lever.
  • a disadvantage of the described embodiment is the relatively high wear of the intermediate lever on all contact surfaces with corresponding friction partners, such as the return spring, the link and the drag lever.
  • Object of the present invention is to present a generic variable-stroke valve train with minimal wear.
  • the camshaft has a base circle, ie a circumferential area of the cam with a constant radius.
  • the intermediate lever remains at rest, ie it is not rotated.
  • this standstill occurs at the contact surfaces of the intermediate lever with the spring element, the intermediate element and the backdrop at the transition from the cam base circle on the cam lobe on an adhesive sliding transition, which leads to a strong wear of the contact surfaces.
  • the intermediate lever is kept permanently in motion upon rotation of the cam according to the invention. Due to the constant movement of the intermediate lever tangential excitation of the spring element is avoided by tearing and on the other hand, the high acceleration forces that are transmitted through the contact points and where unfavorable lubrication conditions due to a static surface pressure, avoided.
  • the friction losses and component wear are significantly reduced and the life of the variable stroke valve train is significantly extended.
  • the inter-lever spins are significantly reduced by the uninterrupted rotational movement, which allows the gas exchange valves to be opened more quickly, and the gas exchange and mixture preparation can be improved.
  • vibration less susceptible As a result, further, the spring element can be made smaller, which, also in connection with the already described reduced acceleration forces of the intermediate lever, significantly higher speeds can be achieved.
  • variable-stroke valve drive is thus substantially more wear-resistant and mechanically stable, ie. H. There are reduced acceleration and vibration forces, whereby vibration problems are reduced and the speed of the internal combustion engine can be easily increased.
  • the embodiment according to claim 13 reduces the acceleration forces occurring in the variable-stroke valve drive in the transition from the Leerhubkurve on the lift curve.
  • the resulting constant opening and closing accelerations of the intermediate lever allow a higher speed of the internal combustion engine.
  • variable stroke valve drive By using an intermediate element according to claim 14 of the variable stroke valve drive is largely free of play and maintenance.
  • a hydraulic valve clearance compensation element is used.
  • An embodiment according to claim 1 5 allows a compact, as well as rigid construction of the variable stroke valve train.
  • the forces or moments to be applied during an adjustment of the gas exchange valve lift can be achieved without difficulty.
  • the cam can get any technically meaningful contour.
  • the variable-stroke valve drive 1 consists essentially of an intermediate lever 2, which is on the one hand slidingly mounted on a slide track 3a of a link 3, which is arranged stationarily in a cylinder head 16.
  • the intermediate lever 2 has a working curve 4 with a zero-stroke curve 4a and a lift curve 4b, wherein a ramp 4c is formed between the zero-stroke curve 4a and the lift curve 4b.
  • the zero stroke curve 4a is in operative connection with a fourth roller element 15, a roller of an intermediate element 5, a drag lever.
  • the operative connection is a line contact between the roller and in a plane perpendicular to the plane largely flat working curve 4.
  • the intermediate lever 5 is on the one hand on a lash adjuster 18, preferably a hydraulic lash adjuster mounted and on the other hand on a gas exchange valve 6.
  • the gas exchange valve 6 and the lash adjuster 18 are mounted in the cylinder head 16.
  • the slide track 3a has a defined radius.
  • a rotation axis 15a of the fourth roller element 15 is the center of curvature of the slide track 3a when the zero stroke curve 4a and the fourth roller element 15 are in operative connection with each other.
  • the intermediate lever 2 On the crank side, the intermediate lever 2 has a first roller element 12 with a first axis of rotation 12a, which is also perpendicular to the plane of the drawing with the slide track 3a in line contact. Coaxially to the first axis of rotation 12a, a second roller element 13 is arranged, which is in operative connection with a second adjusting device 10.
  • the second adjusting device 10 has in the present embodiment, a cam, with the backdrop-side end of the intermediate lever 2 controlled or controlled parallel to the slide track 3a can be moved.
  • the cam may be an eccentric disc or a cam, but other contours are easily used.
  • the intermediate lever 2 has a third roller element 14.
  • the first adjusting device 7 consists essentially of a cam 11, with a peripheral surface 11a, which rotates about a rotation axis 11b.
  • the cam 11 has a radius continuously changing over the circumferential surface 11a and thus differs from a camshaft by the absence of a base circle, that is, a peripheral surface portion 11a of constant radius.
  • the gas exchange valve 6 is cyclically opened and closed, provided in addition to the zero stroke curve 4a and the lifting cam 4b is in operative connection with the fourth roller element 15.
  • the second adjusting device 10 the absolute stroke of the gas exchange valve 6 is set. If the line contact (contact surface 17a) of the fourth roller element 15 is on the zero stroke curve 4a, then the gas exchange valve lift is zero, the line contact is shifted via the ramp 4c to the working curve 4b, the stroke of the gas exchange valve 6 is increased to a maximum value.
  • its contour is largely formed as a circular section.
  • a spring element 9, a leg spring is provided, which is fixed on the one hand to the cylinder head 16 and with a first contact surface 17a close to the Working curve 4 always presses against the intermediate lever 2.
  • a spring element 9 a leg spring
  • the exemplary section shown here by a preferred embodiment of the variable-stroke valve drive 1 shows a section for a single.
  • Gas exchange valve 6 of the internal combustion engine The gas exchange valve 6 may be both an inlet gas exchange valve and an outlet gas exchange valve.
  • the internal combustion engine may have a plurality of gas exchange valves 6 for the inlet and / or outlet side per cylinder. This means that the variable-stroke valve train can be used on both the inlet and outlet side.
  • the number of cylinders of the internal combustion engine has no direct influence on the function of the variable-stroke valve drive 1.
  • the clearance compensation element 18, which is a hydraulic compensation element in the present embodiment, can also by other embodiments, such. B. be realized mechanical compensation elements.
  • the intermediate member 5 may be, for example, a rocker arm instead of a rocker arm.
  • the intermediate element 5 can either be directly in contact with the working curve 4, then the intermediate element-side surface is formed with a radius, or the contact is made via the fourth roller element 15.
  • the spring element 9, which is a leg spring in the present embodiment, can also be replaced by geometrically differently designed spring elements, such as a leaf spring.
  • the roller elements 12 to 15 are preferably ball or needle bearings, a sliding bearing is possible.
  • the intermediate lever 2 can preferably be formed from sheet metal or produced by a casting process.
  • the gate 3 can be detachably or permanently connected to the cylinder head 16.
  • the cam disk 11 of the first adjusting device 7 is rotated largely phase-locked to a crankshaft about the axis of rotation 11b.
  • a camshaft adjusting unit which changes a relative rotational position of the first actuating device 7 within certain limits to the crankshaft rotational position.
  • the working curve 4 in the Way does not emigrate.
  • the working curve 4 is pushed over the fourth roller element 15 in the second contact surface 17b.
  • the second contact surface 17b is in the region of the zero stroke curve 4a, no gas exchange valve movement takes place.
  • the second adjusting device 10 is adjusted and the first roller element 12 is displaced in the direction of the arrow, the second contact surface 17b moves via the ramp 4c into the region of the lifting curve 4b. In this case, the gas exchange valve 6 is opened, and then closed again.
  • the intermediate lever 2 When using a camshaft for the first adjusting device 7, as described in the prior art, the intermediate lever 2 is stationary when the base circle of the camshaft is in operative connection with the third roller element 14. In this time, due to the static surface pressure lubricant in particular from the contact surfaces 17a, 17b urged. With the elevation of the cam, the intermediate lever 2 is pivoted again and in the first moment of the movement there is a dry or mixed friction in the contact surfaces 17a, 17b. By this initial dry or mixed lubrication, the wear is enormously high, which is avoided with the present invention.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Valve Device For Special Equipments (AREA)
  • Valve-Gear Or Valve Arrangements (AREA)

Abstract

The invention relates to a variable stroke valve drive (1) for an internal combustion engine comprising a intermediate lever (2) which is slidingly arranged on a crank path (3a) of a crank arm (3) and is provided with a working cam (4) consisting of a null lifting cam (4a) and a lifting cam (4b), wherein the working cam (4) is actively connected to a gas exchange valve (6) by means of an intermediate element (5), a first adjustment element (7) rotates the intermediate lever (2) oppositely to the elastic force of a spring element (9) around a point (8) located near the crank, the intermediate lever (2) is displaceable along the crank path (3a) by means of a second adjustment element (10), the first adjustment element (7) is provided with a cam plate (11) whose radius continuously increases or reduces on a circumference (11a) with respect to an axis of rotation (11b). The inventive embodiment of the variable stroke valve drive makes it possible to substentially reduce the wear in a valve drive.

Description

Die Erfindung betrifft einen hubvariablen Ventiltrieb für eine Brennkraftmaschine mit den Merkmalen aus dem Oberbegriff des Patentanspruches 1.The invention relates to a variable-stroke valve drive for an internal combustion engine with the features of the preamble of claim 1.

Sie geht von der deutschen Offenlegungsschrift DE 101 23 186 A1 aus. In dieser ist eine mechanische Regelung zur Hubverstellung eines Gaswechselventils, ein hubvariabler Ventiltrieb eines Verbrennungsmotors, beschrieben. Die mechanische Regelung zeichnet sich dadurch aus, dass die Drehzahl- und Lastregelung der Brennkraftmaschine nicht über eine Drosselklappe erfolgt, sondern über den Ventilhub der Gaswechsel-Einlassventile. Um dies zu erreichen, weist die mechanische Regelung einen Zwischenhebel auf, der einerseits schiebebeweglich auf einer Kulissenbahn einer Kulisse gelagert ist und andererseits eine Arbeitskurve mit einer Nullhubkurve und einer Hubkurve aufweist. Die Arbeitskurve steht hierbei über ein Zwischenelement, einem Schlepphebel, mit einem Gaswechselventil in Wirkverbindung. Ferner weist die mechanische Regelung eine Nockenwelle auf, mit der der Zwischenhebel gegen die Federkraft einer Rückstellfeder um einen kulissennahen Punkt gedreht wird, so dass die Anteile zwischen Nullhubkurve und Hubkurve, die mit dem Zwischenelement in Wirkverbindung stehen verschoben werden. Solange sich der Berührpunkt, bzw. die Berührlinie zwischen dem Zwischenhebel, oder einem an diesen angeordneten Rollenelement und der Nullhubkurve befindet, bleibt trotz drehender Nockenwelle das Gaswechselventil geschlossen. Ferner weist die mechanische Regelung ein zweites Stellelement, eine Exzenterwelle auf, die kulissennah auf den Zwischenhebel einwirkt. Durch das Verdrehen der Exzenterwelle wird der Zwischenhebel in der Kulisse parallel zur Kulissenbahn verschoben, wodurch der wirksame Anteil zwischen Hubkurve und Leerhubkurve verändert wird. Der Anteil der Hubkurve bezüglich der Nockenerhebung kann somit vergrößert oder verkleinert werden. Eine Vergrößerung des Hubkurvenanteils entspricht einer Vergrößerung des Gaswechselventilhubes. Eine Verkleinerung des Hubkurvenanteils entspricht einer Verkleinerung des Gaswechselventilhubes, bis wie oben beschrieben, nur noch der Leerhubkurvenanteil mit dem Zwischenhebel in Wirkverbindung steht.It is based on the German patent application DE 101 23 186 A1. In this is a mechanical control for stroke adjustment of a gas exchange valve, a variable-stroke valve train of an internal combustion engine, described. The mechanical control is characterized by the fact that the speed and load control of the internal combustion engine does not take place via a throttle valve, but via the valve lift of the gas exchange intake valves. To achieve this, the mechanical control has an intermediate lever, which is mounted on the one hand slide-movable on a slide track of a link and on the other hand has a working curve with a zero stroke and a lift curve. The working curve is in this case via an intermediate element, a drag lever, with a gas exchange valve in operative connection. Further, the mechanical control has a camshaft, with which the intermediate lever is rotated against the spring force of a return spring to a point close to the stage, so that the shares between Nullhubkurve and lift curve, which are in operative connection with the intermediate element moved. As long as the touch point, or the touch line between the intermediate lever, or arranged on this roller element and the zero stroke curve, the gas exchange valve remains closed despite rotating camshaft. Furthermore, the mechanical control has a second adjusting element, an eccentric shaft, which acts on the intermediate lever near the stage. By rotating the eccentric shaft of the intermediate lever is moved in the backdrop parallel to the slide track, whereby the effective proportion between the lift curve and Leerhubkurve is changed. The proportion of the lift curve with respect to the cam lobe can thus be increased or decreased. An increase in the Hubkurvenanteils corresponds to an increase in Gaswechselventilhubes. A reduction of the Hubkurvenanteils corresponds to a reduction of Gaswechselventilhubes until, as described above, only the Leerhubkurvenanteil is in operative connection with the intermediate lever.

Nachteilig an der beschriebenen Ausgestaltung ist der relativ hohe Verschleiß des Zwischenhebels an allen Kontaktflächen mit korrespondierenden Reibpartnern, wie der Rückstellfeder, der Kulisse und dem Schlepphebel.A disadvantage of the described embodiment is the relatively high wear of the intermediate lever on all contact surfaces with corresponding friction partners, such as the return spring, the link and the drag lever.

Aufgabe der vorliegenden Erfindung ist es, einen gattungsgemäßen hubvariablen Ventiltrieb mit minimiertem Verschleiß darzustellen.Object of the present invention is to present a generic variable-stroke valve train with minimal wear.

Diese Aufgabe wird durch die Merkmale im kennzeichnenden Teil des Patentanspruches 1 dadurch gelöst, dass anstelle einer Nockenwelle eine Kurvenscheibe verwendet wird, deren Radius über den Umfang bezüglich der Drehachse stetig zu- oder abnimmt.This object is achieved by the features in the characterizing part of claim 1, characterized in that instead of a camshaft, a cam is used whose radius increases or decreases continuously over the circumference with respect to the axis of rotation.

Im Eingangs beschriebenen Stand der Technik weist die Nockenwelle einen Grundkreis auf, d. h. einen Umfangsbereich des Nockens mit konstantem Radius. Solange der Grundkreis der Nockenwelle mit dem Zwischenhebel in Wirkverbindung ist, bleibt der Zwischenhebel in Ruhe stehen, d. h. er wird nicht gedreht. Durch diesen Stillstand tritt an den Kontaktflächen des Zwischenhebels mit dem Federelement, dem Zwischenelement und der Kulisse beim Übergang vom Nockengrundkreis auf die Nockenerhebung ein Haft-Gleitübergang auf, der zu einem starken Verschleiß der Kontaktflächen führt.In the prior art described in the introduction, the camshaft has a base circle, ie a circumferential area of the cam with a constant radius. As long as the base circle of the camshaft is in operative connection with the intermediate lever, the intermediate lever remains at rest, ie it is not rotated. By this standstill occurs at the contact surfaces of the intermediate lever with the spring element, the intermediate element and the backdrop at the transition from the cam base circle on the cam lobe on an adhesive sliding transition, which leads to a strong wear of the contact surfaces.

Bei der vorgeschlagenen Ausgestaltung wird jedoch der Zwischenhebel bei Drehung der erfindungsgemäßen Kurvenscheibe permanent in Bewegung gehalten. Durch die ständige Bewegung des Zwischenhebels ist eine Tangentialanregung des Federelementes durch Losreißen vermieden und andererseits werden die hohen Beschleunigungskräfte, die über die Kontaktstellen übertragen werden und an denen ungünstige Schmierungsverhältnisse aufgrund einer statischen Flächenpressung vorliegen, vermieden. In anderen Worten findet erstens durch die vorgeschlagene ständige Schwingbewegung des Zwischenhebels bei Verwendung einer Kurvenscheibe in vorteilhafter Weise ständig ein Öleintrag zwischen die Kontaktflächen der Kontaktpartner Zwischenhebel, Federelement und Zwischenelement, statt. Somit sind die Reibungsverluste und der Bauteilverschleiß wesentlich verringert und die Lebensdauer des hubvariablen Ventiltriebes ist deutlich verlängert. Zweitens sind die Zwischenhebel-Drehbeschleunigungen durch die ununterbrochene Drehbewegung wesentlich verringert, wodurch die Gaswechselventile schneller geöffnet werden können und der Ladungswechsel, sowie die Gemischaufbereitung verbessert werden. Drittens sind Resonanzeffekte der Rückstellfeder durch konstante wirksame Schenkellängen, wie sie beim Stillstand des Zwischenhebels beim Kontakt mit dem Grundkreis auftreten, ausgeschlossen und der hubvariable Ventiltrieb ist mechanisch stabiler, d. h. unter anderem schwingungstechnisch weniger anfällig. Als Folge hieraus kann ferner das Federelement kleiner dimensioniert werden, wodurch, auch in Verbindung mit den bereits beschriebenen reduzierten Beschleunigungskräften des Zwischenhebels, deutlich höhere Drehzahlen erreichbar sind.In the proposed embodiment, however, the intermediate lever is kept permanently in motion upon rotation of the cam according to the invention. Due to the constant movement of the intermediate lever tangential excitation of the spring element is avoided by tearing and on the other hand, the high acceleration forces that are transmitted through the contact points and where unfavorable lubrication conditions due to a static surface pressure, avoided. In other words, firstly by the proposed constant oscillating movement of the intermediate lever when using a cam in an advantageous manner always an oil entry between the contact surfaces of the contact partner intermediate lever, spring element and intermediate element instead. Thus, the friction losses and component wear are significantly reduced and the life of the variable stroke valve train is significantly extended. Secondly, the inter-lever spins are significantly reduced by the uninterrupted rotational movement, which allows the gas exchange valves to be opened more quickly, and the gas exchange and mixture preparation can be improved. Third, resonance effects of the return spring by constant effective leg lengths, as they occur when the intermediate lever is in contact with the base circle, excluded and the variable-stroke valve train is mechanically stable, d. H. Among other things vibration less susceptible. As a result, further, the spring element can be made smaller, which, also in connection with the already described reduced acceleration forces of the intermediate lever, significantly higher speeds can be achieved.

Durch den erfindungsgemäßen Einsatz der Kurvenscheibe wird der hubvariable Ventiltrieb somit wesentlich verschleißfester und mechanisch stabiler, d. h. es treten verringerte Beschleunigungs- und Schwingungskräfte auf, wodurch schwingungstechnische Probleme reduziert sind und die Drehzahl der Brennkraftmaschine problemlos erhöht werden kann.Due to the use of the cam according to the invention, the variable-stroke valve drive is thus substantially more wear-resistant and mechanically stable, ie. H. There are reduced acceleration and vibration forces, whereby vibration problems are reduced and the speed of the internal combustion engine can be easily increased.

Durch die Ausgestaltung gemäß den Merkmalen in den Patentansprüchen 2 mit 9 wird die innere Reibung im gesamten hubvariablen Ventiltrieb nochmals wesentlich reduziert. Durch die vorgeschlagene Ausgestaltung wird somit nochmals der Verschleiß reduziert, sowie die Lebens-, bzw. Einsatzdauer erhöht. Als weiterer positiver Effekt darf die Kraftstoffersparnis aufgrund der verringerten innere Reibung des hubvariablen Ventiltriebs genannt werden.Due to the configuration according to the features in the claims 2 with 9, the internal friction in the entire variable stroke valve drive is again significantly reduced. The proposed embodiment thus reduces the wear again, and increases the life, or duration of use. Another positive effect is the fuel economy due to the reduced internal friction of the variable-stroke valve train.

Durch die Ausgestaltung gemäß Patentanspruch 10 ist eine rein rotatorische Bewegung des Zwischenhebels bei Betätigung der zweiten Stellvorrichtung möglich. Der Drehpunkt ist hierbei der kulissennahe Punkt, bei Verwendung des ersten Rollenelementes somit die Drehachse des ersten Rollenelementes. Translatorische Bewegungen und somit Gleitbewegungen, die Verschleiß bedeuten, treten nicht auf. Ferner ist ein spontanes, d. h. verzögerungsfreies Öffnen und Schließen des Gaswechselventils möglich.Due to the configuration according to claim 10, a purely rotational movement of the intermediate lever upon actuation of the second actuator is possible. The fulcrum here is the near-stage point, thus using the first roller element, the axis of rotation of the first roller element. Translational movements and thus sliding movements, which mean wear, do not occur. Furthermore, a spontaneous, d. H. Delay-free opening and closing of the gas exchange valve possible.

Mit einer Ausgestaltung gemäß der Patentansprüche 11 und 12 wird der Grundkreis einer Nockenwelle simuliert, wodurch ein geschlossenes Gaswechselventil ermöglicht wird, ohne dass die o. g. Nachteile einer herkömmlich bekannten Nockenwelle entstehen.With an embodiment according to the claims 11 and 12, the base circle of a camshaft is simulated, whereby a closed gas exchange valve is made possible without the o. G. Disadvantages of a conventionally known camshaft arise.

Die Ausgestaltung gemäß Patentanspruch 13 reduziert die auftretenden Beschleunigungskräfte im hubvariablen Ventiltrieb beim Übergang von der Leerhubkurve auf die Hubkurve. Die resultierenden konstanten Öffnungs- und Schließbeschleunigungen des Zwischenhebels erlauben eine höhere Drehzahl der Brennkraftmaschine.The embodiment according to claim 13 reduces the acceleration forces occurring in the variable-stroke valve drive in the transition from the Leerhubkurve on the lift curve. The resulting constant opening and closing accelerations of the intermediate lever allow a higher speed of the internal combustion engine.

Durch die Verwendung eines Zwischenelementes gemäß Patentanspruch 14 ist der hubvariable Ventiltrieb weitgehend spiel- und wartungsfrei. Vorzugsweise wird ein hydraulisches Ventilspielausgleichselement eingesetzt.By using an intermediate element according to claim 14 of the variable stroke valve drive is largely free of play and maintenance. Preferably, a hydraulic valve clearance compensation element is used.

Eine Ausgestaltung gemäß Patentanspruch 1 5 erlaubt einen kompakten, sowie steifen Aufbau des hubvariablen Ventiltriebs.An embodiment according to claim 1 5 allows a compact, as well as rigid construction of the variable stroke valve train.

Unter Verwendung einer zweiten Stellvorrichtung gemäß Patentanspruch 16 sind die bei einer Verstellung des Gaswechselventilhubes aufzubringenden Kräfte bzw. Momente problemlos erreichbar. Selbstverständlich kann die Kurvenscheibe jede technisch sinnvolle Kontur erhalten.Using a second adjusting device according to claim 16, the forces or moments to be applied during an adjustment of the gas exchange valve lift can be achieved without difficulty. Of course, the cam can get any technically meaningful contour.

Im Folgenden ist die Erfindung anhand einer Schnittdarstellung von einem bevorzugten Ausführungsbeispiel in einer einzigen Figur näher erläutert.

Figur 1
zeigt einen Schnitt durch einen erfindungsgemäßen hubvariablen Ventiltrieb.
In the following the invention is explained in more detail with reference to a sectional view of a preferred embodiment in a single figure.
FIG. 1
shows a section through a variable-stroke valve drive according to the invention.

Der hubvariable Ventiltrieb 1 besteht im wesentlichen aus einem Zwischenhebel 2, der einerseits schiebebeweglich auf einer Kulissenbahn 3a einer Kulisse 3 gelagert ist, die ortsfest in einem Zylinderkopf 16 angeordnet ist. Am gegenüberliegenden Ende weist der Zwischenhebel 2 eine Arbeitskurve 4 mit einer Nullhubkurve 4a und einer Hubkurve 4b auf, wobei zwischen der Nullhubkurve 4a und der Hubkurve 4b eine Rampe 4c eingeformt ist. In Figur 1 steht die Nullhubkurve 4a mit einem vierten Rollenelement 15, eine Rolle eines Zwischenelements 5, einem Schlepphebel, in Wirkverbindung. Die Wirkverbindung ist ein Linienkontakt zwischen der Rolle und der in einer Ebene senkrecht zur Zeichnungsebene weitgehend ebenen Arbeitskurve 4. Der Zwischenhebel 5 ist einerseits auf einem Spielausgleichselement 18, vorzugsweise einem hydraulischen Ventilspielausgleichselement gelagert und andererseits auf einem Gaswechselventil 6. Das Gaswechselventil 6 und das Spielausgleichselement 18 sind in dem Zylinderkopf 16 montiert. Die Kulissenbahn 3a weist einen definierten Radius auf. Eine Drehachse 15a des vierten Rollenelementes 15 ist der Krümmungsmittelpunkt der Kulissenbahn 3a, wenn die Nullhubkurve 4a und das vierte Rollenelement 15 miteinander in Wirkverbindung stehen.The variable-stroke valve drive 1 consists essentially of an intermediate lever 2, which is on the one hand slidingly mounted on a slide track 3a of a link 3, which is arranged stationarily in a cylinder head 16. At the opposite end, the intermediate lever 2 has a working curve 4 with a zero-stroke curve 4a and a lift curve 4b, wherein a ramp 4c is formed between the zero-stroke curve 4a and the lift curve 4b. In FIG. 1, the zero stroke curve 4a is in operative connection with a fourth roller element 15, a roller of an intermediate element 5, a drag lever. The operative connection is a line contact between the roller and in a plane perpendicular to the plane largely flat working curve 4. The intermediate lever 5 is on the one hand on a lash adjuster 18, preferably a hydraulic lash adjuster mounted and on the other hand on a gas exchange valve 6. The gas exchange valve 6 and the lash adjuster 18 are mounted in the cylinder head 16. The slide track 3a has a defined radius. A rotation axis 15a of the fourth roller element 15 is the center of curvature of the slide track 3a when the zero stroke curve 4a and the fourth roller element 15 are in operative connection with each other.

Kulissenseitig weist der Zwischenhebel 2 ein erstes Rollenelement 12 mit einer ersten Drehachse 12a auf, welches mit der Kulissenbahn 3a ebenfalls in Linienkontakt senkrecht zur Zeichnungsebene steht. Koaxial zur ersten Drehachse 12a ist ein zweites Rollenelement 13 angeordnet, welches mit einer zweiten Stellvorrichtung 10 in Wirkverbindung steht. Die zweite Stellvorrichtung 10 weist im vorliegenden Ausführungsbeispiel eine Kurvenscheibe auf, mit der das kulissenseitige Ende des Zwischenhebels 2 gesteuert oder geregelt parallel zur Kulissenbahn 3a verschoben werden kann. Beispielsweise kann es sich bei der Kurvenscheibe um eine Exzenterscheibe oder auch einen Nocken handeln, jedoch auch andere Konturen sind problemlos einsetzbar.On the crank side, the intermediate lever 2 has a first roller element 12 with a first axis of rotation 12a, which is also perpendicular to the plane of the drawing with the slide track 3a in line contact. Coaxially to the first axis of rotation 12a, a second roller element 13 is arranged, which is in operative connection with a second adjusting device 10. The second adjusting device 10 has in the present embodiment, a cam, with the backdrop-side end of the intermediate lever 2 controlled or controlled parallel to the slide track 3a can be moved. For example, the cam may be an eccentric disc or a cam, but other contours are easily used.

In etwa mittig zwischen dem ersten und dem zweiten Rollenelement (12, 13), sowie der Arbeitskurve.4, weist der Zwischenhebel 2 ein drittes Rollenelement 14 auf. Auf dieses dritte Rollenelement 14 wirkt eine erste Stellvorrichtung 7. Die erste Stellvorrichtung 7 besteht im wesentlichen aus einer Kurvenscheibe 11, mit einer Umfangsfläche 11a, die um eine Drehachse 11b rotiert. Die Kurvenscheibe 11 weist einen über die Umfangsfläche 11a sich stetig verändernden Radius auf und unterscheidet sich somit von einer Nockenwelle durch das Fehlen eines Grundkreises, das heißt eines Umfangsflächenabschnittes 11a mit konstantem Radius.In approximately the middle between the first and the second roller element (12, 13), as well as the working curve. 4, the intermediate lever 2 has a third roller element 14. On this third roller member 14 acts a first adjusting device 7. The first adjusting device 7 consists essentially of a cam 11, with a peripheral surface 11a, which rotates about a rotation axis 11b. The cam 11 has a radius continuously changing over the circumferential surface 11a and thus differs from a camshaft by the absence of a base circle, that is, a peripheral surface portion 11a of constant radius.

Mit der ersten Stellvorrichtung 7 wird das Gaswechselventils 6 zyklisch geöffnet und geschlossen, sofern neben der Nullhubkurve 4a auch die Hubkurve 4b mit dem vierten Rollenelement 15 in Wirkverbindung steht. Mit der zweiten Stellvorrichtung 10 wird der Absoluthub des Gaswechselventils 6 eingestellt. Befindet sich der Linienkontakt (Kontaktfläche 17a) des vierten Rollenelementes 15 auf der Nullhubkurve 4a, dann ist der Gaswechselventilhub null, wird der Linienkontakt über die Rampe 4c auf die Arbeitskurve 4b verschoben, so wird der Hub des Gaswechselventils 6 bis zu einem maximalen Wert vergrößert. Um den Nullhub mit der Nullhubkurve 4a zu realisieren, ist deren Kontur weitgehend als Kreisabschnitt ausgeformt.With the first adjusting device 7, the gas exchange valve 6 is cyclically opened and closed, provided in addition to the zero stroke curve 4a and the lifting cam 4b is in operative connection with the fourth roller element 15. With the second adjusting device 10, the absolute stroke of the gas exchange valve 6 is set. If the line contact (contact surface 17a) of the fourth roller element 15 is on the zero stroke curve 4a, then the gas exchange valve lift is zero, the line contact is shifted via the ramp 4c to the working curve 4b, the stroke of the gas exchange valve 6 is increased to a maximum value. In order to realize the zero stroke with the zero stroke curve 4a, its contour is largely formed as a circular section.

Damit sicher gestellt ist, dass die erste Stellvorrichtung 7 stets mit dem Zwischenelement 2 über das dritte Rollenelement 14 in Wirkverbindung steht, ist ein Federelement 9, eine Schenkelfeder, vorgesehen, das einerseits ortsfest am Zylinderkopf 16 befestigt ist und mit einer ersten Kontaktfläche 17a nahe der Arbeitskurve 4 stets gegen den Zwischenhebel 2 drückt. Selbstverständlich können auch andere Anlagepunkte am Zwischenelement 2 vorgesehen werden.To ensure that the first adjusting device 7 is always in operative connection with the intermediate element 2 via the third roller element 14, a spring element 9, a leg spring, is provided, which is fixed on the one hand to the cylinder head 16 and with a first contact surface 17a close to the Working curve 4 always presses against the intermediate lever 2. Of course, other investment points on the intermediate element 2 can be provided.

Der hier gezeigte exemplarische Schnitt durch eine bevorzugte Ausgestaltung des hubvariablen Ventiltriebs 1 zeigt einen Schnitt für ein einzelnes. Gaswechselventil 6 der Brennkraftmaschine. Das Gaswechselventil 6 kann sowohl ein Einlass-Gaswechselventil als auch ein Auslass-Gaswechselventil sein. Ferner kann die Brennkraftmaschine mehrere Gaswechselventile 6 für die Einlass- und/oder Auslassseite je Zylinder aufweisen. Das heißt, der hubvariable Ventiltrieb kann sowohl einlass- als auch auslassseitig eingesetzt werden. Die Anzahl der Zylinder der Brennkraftmaschine hat keinen direkten Einfluss auf die Funktion des hubvariablen Ventiltriebs 1. Durch Zusammenfassen mehrerer Stellvorrichtungen 7, 10, beispielsweise durch die Verwendung jeweils einer Welle für mehrere Kurvenscheiben 11, kann für jede Einlass-, bzw. Auslassseite einer Zylinderbank jeweils ein hubvariabler Ventiltrieb 1 vorgesehen werden.The exemplary section shown here by a preferred embodiment of the variable-stroke valve drive 1 shows a section for a single. Gas exchange valve 6 of the internal combustion engine. The gas exchange valve 6 may be both an inlet gas exchange valve and an outlet gas exchange valve. Furthermore, the internal combustion engine may have a plurality of gas exchange valves 6 for the inlet and / or outlet side per cylinder. This means that the variable-stroke valve train can be used on both the inlet and outlet side. The number of cylinders of the internal combustion engine has no direct influence on the function of the variable-stroke valve drive 1. By combining several actuators 7, 10, for example, by using a respective shaft for a plurality of cams 11, for each inlet or outlet side of a cylinder bank respectively a variable-stroke valve drive 1 are provided.

Das Spielausgleichselement 18, welches im vorliegenden Ausführungsbeispiel ein hydraulisches Ausgleichselement ist, kann ebenfalls durch andere Ausführungsvarianten, wie z. B. mechanische Ausgleichselemente realisiert sein. Ferner kann das Zwischenelement 5 anstelle eines Schwinghebels beispielsweise ein Kipphebel sein. Das Zwischenelement 5 kann entweder direkt mit der Arbeitskurve 4 in Kontakt stehen, dann ist die zwischenelementseitige Oberfläche mit einem Radius auszuformen, oder die Berührung erfolgt über das vierte Rollenelement 15. Die zweite Stellvorrichtung 10 kann neben einer Exzenterverstellung auch eine Schubstangenverstellung bzw. eine hydraulische oder elektromechanische Stelleinrichtung sein. Das Federelement 9, welches im vorliegenden Ausführungsbeispiel eine Schenkelfeder ist, kann auch durch geometrisch anders ausgestaltete Federelemente, wie beispielsweise eine Blattfeder, ersetzt werden. Die Rollenelemente 12 bis 15 sind bevorzugt kugel- oder nadelgelagert, auch eine Gleitlagerung ist möglich. Der Zwischenhebel 2 kann ist vorzugsweise aus Blech geformt oder in einem Gießverfahren hergestellt. Die Kulisse 3 kann lösbar oder unlösbar mit dem Zylinderkopf 16 verbunden sein.The clearance compensation element 18, which is a hydraulic compensation element in the present embodiment, can also by other embodiments, such. B. be realized mechanical compensation elements. Further, the intermediate member 5 may be, for example, a rocker arm instead of a rocker arm. The intermediate element 5 can either be directly in contact with the working curve 4, then the intermediate element-side surface is formed with a radius, or the contact is made via the fourth roller element 15. The second adjusting device 10, in addition to a Exzenterverstellung also a push rod adjustment or a hydraulic or be electromechanical adjusting device. The spring element 9, which is a leg spring in the present embodiment, can also be replaced by geometrically differently designed spring elements, such as a leaf spring. The roller elements 12 to 15 are preferably ball or needle bearings, a sliding bearing is possible. The intermediate lever 2 can preferably be formed from sheet metal or produced by a casting process. The gate 3 can be detachably or permanently connected to the cylinder head 16.

Beim Betrieb der Brennkraftmaschine wird die Kurvenscheibe 11 der ersten Stellvorrichtung 7 weitgehend phasenstarr zu einer Kurbelwelle um die Drehachse 11b gedreht. Um die Kraftstoffeinsparung des hubvariablen Ventiltriebs jedoch vollständig ausnutzen zu können, kann beispielsweise eine Nockenwellenverstelleinheit vorgesehen werden, die eine Relativdrehlage der ersten Stellvorrichtung 7 in bestimmten Grenzen zur der Kurbelwellendrehlage verändert. Durch die Drehbewegung der ersten Stellvorrichtung 7 wird der, von dem Federelement 9 gegen die Kurvenscheibe 11 gedrückte Zwischenhebel 2 um den kulissennahen Punkt 8 gedreht. Wird auf das erste Rollenelement 12 verzichtet, dann wandert der kulissennahe Punkt aus. Wird das erste Rollenelement 12 verwendet, dann ist der Drehmittelpunkt (kulissennaher Punkt 8) des Zwischenhebels 2 der Mittelpunkt des ersten Rollenelementes 12, der bei einer Drehung des Zwischenhebels 2 in vorteilhafter Weise nicht auswandert. Hierbei wird die Arbeitskurve 4 in der Weise nicht auswandert. Hierbei wird die Arbeitskurve 4 in der zweiten Kontaktfläche 17b über das vierte Rollenelement 15 geschoben. Solange die zweite Kontaktfläche 17b im Bereich der Nullhubkurve 4a ist, erfolgt keine Gaswechselventilbewegung. Wird die zweite Stellvorrichtung 10 verstellt und das erste Rollenelement 12 in Pfeilrichtung verschoben, so wandert die zweite Kontaktfläche 17b über die Rampe 4c in den Bereich der Hubkurve 4b. In diesem Fall wird das Gaswechselventil 6 geöffnet, und anschließend wieder geschlossen.During operation of the internal combustion engine, the cam disk 11 of the first adjusting device 7 is rotated largely phase-locked to a crankshaft about the axis of rotation 11b. However, in order to fully exploit the fuel economy of the variable-stroke valve drive, it is possible, for example, to provide a camshaft adjusting unit which changes a relative rotational position of the first actuating device 7 within certain limits to the crankshaft rotational position. By the rotational movement of the first adjusting device 7, the, pressed by the spring element 9 against the cam 11 intermediate lever 2 is rotated about the point near the point 8. If the first roller element 12 is dispensed with, then the point close to the stage travels. If the first roller element 12 is used, then the center of rotation (near-point 8) of the intermediate lever 2, the center of the first roller element 12, which does not emigrate at a rotation of the intermediate lever 2 in an advantageous manner. Here, the working curve 4 in the Way does not emigrate. In this case, the working curve 4 is pushed over the fourth roller element 15 in the second contact surface 17b. As long as the second contact surface 17b is in the region of the zero stroke curve 4a, no gas exchange valve movement takes place. If the second adjusting device 10 is adjusted and the first roller element 12 is displaced in the direction of the arrow, the second contact surface 17b moves via the ramp 4c into the region of the lifting curve 4b. In this case, the gas exchange valve 6 is opened, and then closed again.

Bei Verwendung einer Nockenwelle für die erste Stellvorrichtung 7, wie im Stand der Technik beschrieben, steht der Zwischenhebel 2 still, wenn der Grundkreis der Nockenwelle mit dem dritten Rollenelement 14 in Wirkverbindung steht. In dieser Zeit wird aufgrund der statischen Flächenpressung Schmiermittel insbesondere aus den Kontaktflächen 17a, 17b gedrängt. Mit der Erhebung des Nockens wird der Zwischenhebel 2 erneut geschwenkt und im ersten Moment der Bewegung findet eine Trocken- bzw. Mischreibung in den Kontaktflächen 17a, 17b statt. Durch diese anfängliche Trocken- bzw. Mischschmierung ist der Verschleiß enorm hoch, der mit der vorliegenden Erfindung vermieden wird.When using a camshaft for the first adjusting device 7, as described in the prior art, the intermediate lever 2 is stationary when the base circle of the camshaft is in operative connection with the third roller element 14. In this time, due to the static surface pressure lubricant in particular from the contact surfaces 17a, 17b urged. With the elevation of the cam, the intermediate lever 2 is pivoted again and in the first moment of the movement there is a dry or mixed friction in the contact surfaces 17a, 17b. By this initial dry or mixed lubrication, the wear is enormously high, which is avoided with the present invention.

Im Folgenden wird das erfindungswesentliche Merkmal nochmals mit seinen wesentlichen Vorteilen erläutert:

  • Durch die Verwendung der erfindungsgemäßen Kurvenscheibe 11 ist der Zwischenhebel 2 stets in Bewegung, so dass keine statischen Flächenpressungen in den Kontaktflächen 17a,17b auftreten und ständig ausreichende Schmierung der Kontaktflächen 17a, 17b gewährleistet ist. Somit führt die erfindungsgemäße Ausgestaltung zu deutlich weniger Reibung und deutlich weniger Verschleiß. Darüber hinaus sind die Zwischenhebelöffnungs- und Schließbeschleunigungen durch die Verwendung der Kurvenscheibe 11 wesentlich reduziert, wodurch deutlich höhere Drehzahlen der Brennkraftmaschine möglich sind. Als weiterer Vorteil daraus ist die mögliche kleinere Dimensionierung des Federelements 9 anzuführen. Ferner sind Resonanzeffekte in dem Federelement 9 durch die ständige Bewegung des Zwischenhebels 2 vermieden. Durch die Optimierung des Federelementes 9 sind wiederum höhere Drehzahlen erreichbar, bei gleichzeitig minimierter Reibung und minimiertem Verschleiß.
In the following, the feature essential to the invention will be explained again with its essential advantages:
  • By using the cam 11 according to the invention, the intermediate lever 2 is always in motion, so that no static surface pressures in the contact surfaces 17a, 17b occur and constantly adequate lubrication of the contact surfaces 17a, 17b is ensured. Thus, the inventive design leads to significantly less friction and significantly less wear. In addition, the Zwischenhebelöffnungs- and closing accelerations are significantly reduced by the use of the cam 11, which significantly higher engine speeds are possible. Another advantage of this is the possible smaller dimensions to lead the spring element 9. Furthermore, resonance effects in the spring element 9 are avoided by the constant movement of the intermediate lever 2. By optimizing the spring element 9 higher speeds are again achievable, while minimizing friction and minimized wear.

Bezugszeichenliste:LIST OF REFERENCE NUMBERS

1.1.
Hubvariabler VentiltriebHubvariabler valve drive
2.Second
Zwischenhebelintermediate lever
3.Third
Kulissescenery
3a.3a.
Kulissenbahnlink path
4.4th
Arbeitskurveworking curve
4a.4a.
Nullhubkurvezero stroke
4b.4b.
Hubkurvestroke curve
4c.4c.
Ramperamp
5.5th
Zwischenelementintermediate element
6.6th
GaswechselventilGas exchange valve
7.7th
Erste StellvorrichtungFirst adjusting device
8.8th.
Kulissennaher PunktKulissennaher point
9.9th
Federelementspring element
10.10th
Zweite StellvorrichtungSecond actuator
11.11th
Kurvenscheibecam
11a.11a.
Umfangsflächeperipheral surface
11b.11b.
Drehachseaxis of rotation
12.12th
Erstes RollenelementFirst roller element
12a12a
erste Drehachsefirst axis of rotation
13.13th
Zweites RollenelementSecond roller element
14.14th
Drittes RollenelementThird roller element
15.15th
Viertes RollenelementFourth roller element
15a.15a.
zweite Drehachsesecond axis of rotation
16.16th
Zylinderkopfcylinder head
17a.17a.
Erste KontaktflächeFirst contact area
17b.17b.
Zweite KontaktflächeSecond contact surface
18.18th
SpielausgleichselementLash adjuster

Claims (16)

  1. A variable-stroke valve drive (1) for an internal combustion engine, comprising an intermediate lever (2) slidably movable at one end on a slide track (3a) of a slide (3) whereas the other end comprises a working cam (4) with a zero stroke curve (4a) and a stroke curve (4b), wherein
    the working cam (4) is operatively connected to a gas change valve (6) via an intermediate element (5) and wherein
    a first adjusting device (7) is provided for rotating the intermediate lever (2) around a point (8) near the slide and against the force of a spring element (9), wherein
    the intermediate lever (2) is movable by a second adjusting device (10) along the guide track (3a),
    characterised in that the first adjusting device (7) comprises a cam plate (11) having a radius which continuously increases or decreases around a periphery (11a), relative to an axis of rotation (11b).
  2. A variable-stroke valve drive according to claim 1,
    characterised in that the intermediate lever (2) is mounted on the guide track (3a) via a first roller element (12).
  3. A variable-stroke valve drive according to claim 2,
    characterised in that the first roller element (12) is disposed on the intermediate lever (2).
  4. A variable-stroke valve drive according to any of claims 1 to 3,
    characterised in that the first adjusting device (7) is operatively connected to the intermediate lever (2) via a second roller element (13).
  5. A variable-stroke valve drive according to claim 4,
    characterised in that the second roller element (13) is disposed on the intermediate lever (2).
  6. A variable-stroke valve drive according to any of the previously-mentioned claims,
    characterised in that the second adjusting device (10) is operatively connected to the intermediate element (2) via the first roller element (12) or a third roller element (14).
  7. A variable-stroke valve drive according to claim 6,
    characterised in that the third roller element (14) is mounted on the intermediate lever (2).
  8. A variable-stroke valve drive according to any of the previously-mentioned claims,
    characterised in that the intermediate element (5) is operatively connected to the working cam (4) at a second contact surface (17b).
  9. A variable-stroke valve drive according to any of the previously-mentioned claims,
    characterised in that the intermediate element (5) has a fourth roller element (15) operatively connected to the working cam (4) at the surface (17b).
  10. A variable-stroke valve drive according to any of the previously-mentioned claims,
    characterised in that the guide track (3a) is an arc of a circle.
  11. A variable-stroke valve drive according to any of the previously-mentioned claims, wherein the fourth roller element (15) has an axis of rotation (16a),
    characterised in that the axis of rotation (15a) is a centre of a circle of the guide track (3a) when the zero stroke curve (4a) is operatively connected to the fourth roller element (15).
  12. A variable-stroke valve drive according to any of the previously-mentioned claims,
    characterised in that the zero stroke curve (4a) is an arc of a circle.
  13. A variable-stroke valve drive according to any of the preceding claims,
    characterised in that a slope (4c) is formed between the zero stroke curve (4a) and the stroke curve (4b).
  14. A variable-stroke valve drive according to any of the preceding claims,
    characterised in that the intermediate element (5) is a rocking lever or rocker arm.
  15. A variable-stroke valve drive according to any of the previous claims, wherein the internal combustion engine has a cylinder head, characterised in that the guide (3) is disposed in the cylinder head.
  16. A variable-stroke valve drive according to any of the preceding claims,
    characterised in that the second adjusting device (10) comprises a second cam plate.
EP05700827A 2004-02-20 2005-01-12 Variable stroke valve drive for an internal combustion engine Active EP1716318B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102004008389A DE102004008389A1 (en) 2004-02-20 2004-02-20 Valve drive for an I.C. engine comprises a first adjusting device with a cam whose radius increases or decreases over a periphery with respect to a rotating axle
PCT/EP2005/000199 WO2005090757A1 (en) 2004-02-20 2005-01-12 Variable stroke valve drive for an internal combustion engine

Publications (2)

Publication Number Publication Date
EP1716318A1 EP1716318A1 (en) 2006-11-02
EP1716318B1 true EP1716318B1 (en) 2007-05-30

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US (1) US7225773B2 (en)
EP (1) EP1716318B1 (en)
DE (2) DE102004008389A1 (en)
ES (1) ES2285673T3 (en)
WO (1) WO2005090757A1 (en)

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KR100993368B1 (en) * 2008-01-22 2010-11-09 현대자동차주식회사 Continuous variable valve lift apparatus
KR100969074B1 (en) * 2008-04-14 2010-07-09 현대자동차주식회사 Continuous variable valve lift device
DE102008064377B4 (en) 2008-12-22 2016-09-08 Bayerische Motoren Werke Aktiengesellschaft Mounting device and method for a torsion spring and an intermediate lever of a variable-stroke valve drive
US8408172B2 (en) 2009-09-14 2013-04-02 Delphi Technologies, Inc. High efficiency lift profiler for an internal combustion engine
DE102010048708A1 (en) * 2010-10-19 2012-04-19 Kolbenschmidt Pierburg Innovations Gmbh Mechanically controllable valve train
DE102012109538A1 (en) * 2012-10-08 2014-04-10 Kolbenschmidt Pierburg Innovations Gmbh Mechanically controllable valve drive for a reciprocating engine
FR3022414B1 (en) * 2014-06-12 2016-07-01 Mmt Sa MECATRONIC ASSEMBLY FOR DRIVING AN EXTERNAL BODY USING A BRUSHLESS MOTOR AND A SINGLE ASSEMBLY OF ELECTRONIC COMPONENTS.
DE102015210671A1 (en) * 2015-06-11 2016-12-15 Robert Bosch Gmbh Battery cell with a disposed within a second terminal first terminal
DE102018130428A1 (en) * 2018-11-30 2020-06-04 Bayerische Motoren Werke Aktiengesellschaft Variable valve train with at least two working positions

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE818274C (en) * 1947-02-24 1951-10-25 Austin Motor Co Ltd Cams for controlling the valves of internal combustion engines
FR2519375B1 (en) * 1981-12-31 1986-07-11 Baguena Michel VARIABLE VALVE FOR FOUR-STROKE ENGINE
WO1993008377A1 (en) * 1991-10-25 1993-04-29 Peter Kuhn Device for actuating the valves in an internal-combustion engine by means of rotating cams
US6955146B2 (en) * 2000-12-11 2005-10-18 Iav Gmbh Ingenieurgesellschaft Auto Und Verkehr System for variably actuating valves in internal combustion engines
DE50103100D1 (en) * 2001-05-03 2004-09-09 Sts System Technology Services Mechanical regulation of the stroke adjustment of the intake valve of an internal combustion engine
DE10123186A1 (en) * 2001-05-12 2002-11-14 Bayerische Motoren Werke Ag Valve gear device for variable lift adjustment is for gas exchange valve of internal combustion engine and has valve vai intermediary of transmission component effectively connected to roller movable around rotary axis
DE10235401A1 (en) * 2002-08-02 2004-02-12 Bayerische Motoren Werke Ag Lift stroke-variable valve gear for cylinder head of internal combustion engine has second pivoting lever installed stationary on first lever to form one-piece and material uniform double lever arrangement
DE10235400A1 (en) * 2002-08-02 2004-02-19 Bayerische Motoren Werke Ag Cylinder head for an internal combustion engine with a variable stroke valve train
DE10235403A1 (en) * 2002-08-02 2004-02-12 Bayerische Motoren Werke Ag Swivel lever for a variable stroke valve train

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DE502005000790D1 (en) 2007-07-12
US20070012269A1 (en) 2007-01-18
US7225773B2 (en) 2007-06-05
EP1716318A1 (en) 2006-11-02
DE102004008389A1 (en) 2005-09-08
ES2285673T3 (en) 2007-11-16

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