DE102007033821A1 - Actuating unit for variable or fully variable valve gear device of internal combustion engine, has output bearing surface movable around axial point, and formed as adjustable work curve, where curve is formed taperedly and sectionally - Google Patents

Abstract

The unit (1a) has an output bearing surface movable around an axial point, and formed as an adjustable work curve, where the work curve is formed taperedly and sectionally. The output bearing surface includes a flat, broad layer, where a narrow layer is attached at the arched layer. The layers fix a longitudinal direction of the work curve. The work curve is provided at sides which are detachable from the axial point such that position shift of the curve is enabled in the longitudinal direction by deviation of the unit.

Description

The The present invention relates to an actuating means in particular intermediate, swivel, towing, oscillating or tilting lever, for a valve train of an internal combustion engine, in particular for the indirect actuation of at least one gas exchange valve, with a driven tread, in particular pivotally can be displaced by one axis point. Furthermore, the invention relates to a variable or fully variable valve drive device which is an inventive Actuating means comprises.

State of the art

variable and fully variable valve trains are characterized by the fact that they the stroke, the opening time, the opening width or all these technical parameters at the same time or in specific ones Sequence of a gas exchange valve can adjust. For multi-valve loading and a Mehrventilauslass a combustion chamber of an internal combustion engine the individual gas exchange valves of an inlet or an outlet frequently controlled synchronously. It is also possible the individual gas exchange valves of the same type delayed to each other. Are several gas exchange valves of the same Type per cylinder, a lever is often a double or multi-lever, each of which all gas exchange valves of a type per combustion chamber or even per cylinder bank influenced or operated.

From A company of the Schunk Group, Germany, is a lever known to see the representative of the applicant, in the well-known in the automotive industry system "Valvetronic" BMW AG can be used. The lever stands out in sections, sidecutouts and extensions or rejuvenations out.

Ideally is a variable valve train, in particular a fully variable valve train to create, with the prevailing in the valve train accelerations can handle. For this purpose it should be avoided if possible, in particular in a double lever system, single imbalances in the moving To allow parts of the valve train.

From the DE 102 61 304 A1 a valve lifting device for variable valve control of the gas exchange valves of an internal combustion engine with an intermediate lever and a rocker arm is known, which is particularly suitable for high speeds. The resulting at high valve accelerations and high speeds by the movement of the gear members of the valve lift high mass forces and moments acting on the valve gear and the corresponding valve mechanism are reduced by the fact that in the known embodiment, the pivot point of the rocker between the roller and the guide roller, is provided in particular centrally and the pivot point of the rocker arm is thus between the two rollers, the masses are balanced and the rocker arm act only low mass forces and low holding and adjusting forces, since the axis of rotation of the rocker arm and the standing axis of the rocker arm arranged on a vertical axis are. This also leads to the fact that the moving masses, which act on the valve lift, are very low and thus high speeds can be achieved.

This principle of mass balance is, for example, from the DE 60 30 59 81 T2 known.

The mass balance as described above per se is not the only desired design criterion in the design of valve train components, in particular of actuators for gas exchange valves. Although the mass balance, among other things, has a favorable effect on the noise and vibration behavior of the valve train, in principle, in the case of valve train components, which are known to undergo alternating and strong rotational accelerations during operation, additional attention must be paid to low mass inertia. This problem of a valve train, which - to put it simply - should be made of light components, is for a cam follower in the DE 102 18 026 A1 addressed. This prior art describes, in particular with regard to the four- or five-valve technology, an optimization of a cam follower, at least in the region of its valve stem support, in order to solve the existing installation space problems. The cam follower is narrower at one end than over its remaining extent. At the narrower end, the side walls have a lower average wall thickness than over their further length. Due to the narrow design of the cam follower at one end in conjunction with the thinned trained guide cheeks, the mass moment of inertia of the cam follower is further reduced. This has a favorable effect on the installation size, at least in the area of the valve stem support, but it is virtually useless to use. Thus, a problem seems to have been discussed here, to which then no practical solution can be offered.

The teaching of this prior art is thus space saving and reduction of the moment of inertia by narrow formation of at least the valve stem support and thinning of the guide cheeks of the sheet follower made from sheet metal or by forming or casting technology. The axle point of the cam follower is stationary. The contact surface with a cam follower is as a swivel joint consider. There is no longitudinal movement.

The basic function of variable valve lift is, for example, the WO 2004 088 094 A2 or the DE 10 2004 003 327 A1 or the one already mentioned DE 102 61 304 A1 refer to.

Out For better clarity the scope of revelation of the writings of the above cited Prior art by the above references in relation to the also components used here in full in the present patent application included, to the general construction variants of a fully variable Valve drive represent.

invention description

The Professional world has a need for valve drives that are high and highest speeds of the internal combustion engine suitable are and especially at these high speeds noisy and run with low vibration and as little power as possible Consuming spin changes. After another Aspect, it is helpful when the cost of materials for individual Parts of a variable valve train can be kept low.

The improved satisfaction of this need succeeds by an actuating means with the features of claim 1 and by embodiments thereof as stated in the dependent claims are. A particularly suitable lever is specified in claim 16. An inventive fully variable valve train is specified in claim 17.

investigations have shown that in part accelerations of more than 1000 g on the moving parts of an inventive variable valve train can act. The metal manufactured levers, d. H. the actuating means, shows at the partially occurring accelerations unwanted flow behavior. According to another aspect, the intermediate lever is possible unbalance-free design. In a double intermediate lever or a Fork levers should therefore be as similar as possible to the two partial levers to shape each other. Through the reduction or through the Omitting lever parts that are not for the valvetrain are necessary, the total mass of the lever is considerable reduced. Manufacturing inaccuracies between two levers, which experience shows despite largest manufacturing care can occur keep themselves within limits by reducing the total mass per lever. Advantageously, the shaping portions of the lever are tapered so that the volume in the back, d. H. in the second narrower Section, the lever only on a third previously known masses is reduced. Through the recesses or perforations on both sides of the web of the working curve and this if necessary opposite also reduces the possible relative deviation between two individual levers, which is actually possible should be identical. An inventive actuating means or lever that weighs only 30 g according to one embodiment, has even with a 10 percent relative weight gain (exemplary Production test limit in the intermediate production test) only an absolute weight gain of 3 g while so far known actuating means or lever with a typical Weight of 100 g already a deviation of 10 g in the same manufacturing tolerance band have.

The The present invention is equally applicable to single levers as applied to multiple or double lever, especially intermediate lever with working curves.

According to the invention designed the output tread as an adjustable working curve. This allows the actuating means advantageously in used variable or fully variable valve train devices become. The output tread, you could Also refer to as a working surface, has a surface contour on. The individual areas of the surface contour along The working surface has different distances from a central axis point. About this are by means of the working surface the opening behavior and the opening width of a gas exchange valve to be connected affected. The work surface is profiled so. You can also say that the working surface is height-variable or wavy. The corrugation of the working surface is bent. It switches between concave and convex.

The Output tread is at least partially tapered educated. In one aspect of the present invention the taper of the driven tread as special technical feature because they are the general inventive Idea of mass reduction accommodates. Preferably, the Rejuvenation so realized that the driven tread a wider, especially arched, first section includes, to which a second, narrower section followed. By the rejuvenation or the sections narrower design of the driven tread succeeds it, the inertia and in particular the moment of inertia of the actuating means to the running through the axle point To reduce pivot axis advantageous.

The first wider and the second narrower sections determine the longitudinal orientation of the working curve of the actuating means. The working curve is located at the lowest, from the axle point farthest side, preferably by a pivoting of the actuating means a change in position of the working curve in the longitudinal direction is made possible. As a result, an additional output lever to be accumulated, such as a tilting or pivoting lever, comes in contact at another point on the working curve, in particular in line contact. The line contact allows a broader power transmission. Due to the change in position, the adjustability of the technical valve train parameters mentioned above is made possible, ie the valve drive can be designed to be variable or fully variable. The described design of the driven tread and the described course of the working curve, the actuating means is particularly well suited for high and high speeds of the internal combustion engine.

The Actuating means can be designed in particular as an intermediate lever be, on the output side a pan or rocker arm attachable is, via which a gas exchange valve operable is. However, the actuating means can also be used as a swivel or Rocker be formed, which at least one gas exchange valve directly operated. These two variants can can also be combined, resulting in a particularly advantageous mass reduction contributes to the overall system. The smoothness of the valve train is of this combination of the invention favorably influenced.

Prefers the actuating means has at least one recess. Advantageously, this can further reduce the mass of the Actuating means can be achieved. Even the imbalance can favorably influenced by suitable positioning of the recess become. The at least one recess serves to reduce the Mass inertia, in particular for reducing the moment of inertia around the pivot axis passing through the axle point. Advantageous are in cross-section drop-shaped or oval configurations the at least one recess. A particularly favorable mass reduction or distribution can by means of the actuating means through recesses in the form of perforations or Cavities are reached. These perforations or cavities advantageously along their longitudinal extent a changing, especially rejuvenating Cross-section on. Due to the changing perforation or cavity cross sections succeeds, the strength and Stiffness of the structure of the actuating means to the Use case, while the desired mass reduction is reached. In the sense of a double-T-carrier can be Lay cuts through the core of the lever. The lever, similar to the double T-beam is designed, especially in its central area learns through its wraparound walls around the central recess a special rigidity. These are force-conducting or -aufnehmende Lever areas stronger or more massive dimensioned d. H. in such areas, the cavity becomes less bulky executed.

With in other words, where the force is required, leave more material to a functional strength or To ensure rigidity while in places the less to the power line or support contribute, material left out and the lever thus slimmer and is easier to train.

The Exit window of the at least one recess or perforation or cavity from the actuator body becomes on the surface of the actuator body limited by surface margins. These surface edges Run at least partially predominantly parallel to those closest to the surface edge portions, Outer edge contour sections of the actuating means. The hollowing out of the actuating means with a along the wall thickness determined by the stability from outer edge contours of the same leads to a particularly effective mass reduction. At the same time can by appropriate Dimensioning the distance between a surface edge section and the nearest outer contour that can be assigned to it the strength and rigidity of the structure of the actuator favorably influenced and adapted to the application.

Especially It is advantageous and preferred if several by the actuating means passing through, in particular, each other inside the actuating means intersecting or cutting recesses in the actuator are incorporated, which in the interior of the actuating means one or more contiguous recess vaults form. The vaulted recesses or cavities In addition to the invention Rejuvenation of the output surface reducing to the inertia. It is particularly advantageous if the vault structures of the cavities so in the actuator are incorporated, that despite massive weight reduction, for example to one third of the weight of those known in the art Lever or even lower, the strength or stiffness comparatively is only slightly reduced.

Advantageously, the driven tread is formed on a web-like, converging in the longitudinal direction of the first broader, in particular lobe-shaped section towards the narrower section towards the extension, which at least in the second narrower section horn-like away from the camber surface of the wider section and ascending from her is trained. The descent and ascent from and out of the camber surface is helpful to the proper functioning of the lever. Because the opposing forces exerted by the output lever on the actuating means in the second narrower section are smaller than in the first broader section, the second section can be tapered, wherein the lever remains sufficiently resistant to the forces and accelerations occurring in this area. Taking into account that the second narrower portion is the part of the actuating means farthest from the pivot axis, a mass reduction in this range has a particularly advantageous effect on the moment of inertia about the pivot axis passing through the axis point.

Especially it is preferred if the extension a particular rounded Pointed and averted on his from the first broader section Side, beyond the second narrower section and beyond the top comprises a third section, in one in the direction of its base widening base goes over and by means of the base on an outer surface the actuating means is supported, wherein the base in particular in one piece with the outer surface is trained. The third to the actuator body returning section supports the extension, in particular the second narrower section, wherein the support effect by the diverging pedestal is reinforced. This training makes it possible below the second and third sections a recess to work into the extension, which in turn further mass saving is possible. Since this mass saving in second-widest away from the pivot axis, it acts very favorable to the moment of inertia reduction out. The one-piece design of the base with the outer surface of the actuating means on which it is supported results a robust lever that due to the mass reduction due to the Nevertheless, training is easy.

The Vaulting of the first wider section is along the Formed longitudinally of the working curve. Especially can the driven tread in the area of the wider section normal to the working curve at least in the working curve immediately be formed just adjacent areas. This is the bearing surface for the line contact of the output lever in Compared to the second section bigger and it can thus larger in the first broader section Forces transferred operationally become.

Around especially in the first section one in comparison with the plane Training greater contribution to the desired Mass reduction, it is advantageous if the shape of the Surface of the driven tread in terms of on your longitudinal extension of the shape of the surface a rail, like a railroad track, at least similar is. Due to the fact that the vaulting is also in Transversal direction is formed, on the one hand continue to save mass, on the other hand is similar by a profile which is the cross section of a railroad track at its top has created a structure that is particularly large Force supports can endure without affecting the function of the lever becomes. The surface may be additional in this area be hardened to enhance this effect yet.

The Output tread can be in the longitudinal direction of the working curve between the first wider section and the second narrower section Section a particular just as wide Nullhubabschnitt as the have wider section in which the working curve related on the zero stroke section each limiting transition areas is concave to the sections. The concave zero stroke section but may alternatively be narrower than the first wide section be formed to save even more mass. This is possible in particular, since in operation in the zero-stroke range in usually lower forces than in the first broader section act on the output surface. A zero-stroke range is required for correct operation of the valve train. If it is designed and dimensioned as described, it can simply in the inventive overall technical concept be integrated into the lever.

The Working curve points in the area between the wider section and the narrower section, especially in the transition area the Nullhubabschnittes to the narrower section a turning point on, in particular, the steepness of the working curve in comparison to their steepness in the transition region of Nullhubabschnittes is formed larger to the wider section. This training integrates one for full variability the valve gear and its correct function implemented design in the mass reduction concept of the invention.

The Extension of the second narrower section normal to Working curve measures in proportion to the extension of the first wider section normal to the working curve half or less than half, more preferably a third or less than a third. The mass reduction and in particular the inertia torque reduction succeeds all the more effectively the smaller the width ratio for a given width of the first section is.

The invention is preferably as a double fork lever, in particular as a double intermediate lever, designed for a valve train of an internal combustion engine. It comprises in this embodiment, a first and a second actuating means according to the invention, wherein the two actuating means sit on a common axis equipped with lateral abutment fasteners, so that each of the actuating means about the same pivot axis, but the first actuating means at a first axis point and the second actuating means at a second, from the first axis axially spaced axle point, is pivotable. In the embodiment as a double fork intermediate lever advantageously two gas exchange valves can be operated simultaneously or synchronously, with the already described benefits of inertia and inertia reduction for each of the actuating means ie beat for both partial lever and thus for the fork lever as a whole favorably book.

Preferably becomes the actuating means according to the invention or the double fork lever according to the invention in a variable or fully variable valve drive device used. It is particularly preferred if both intermediate and output lever are designed according to the invention. By the invention Training succeeds in producing a light, low-noise and low-vibration to design a revving valve train.

figure description

Further advantageous properties and embodiments of the invention are described with reference to the drawings explained below. In these drawings, without the invention being limited to the present invention To limit embodiments,

1 : Oblique side view of a valve lifting device of a variable valve drive according to the invention with a first embodiment of an actuating means according to the invention as a double intermediate lever;

2 : Detail oblique view of the double intermediate lever of the valve lifting device according to the invention 1 ; the output running surfaces of the two partial levers, characterized by the suffixes a and b, with their working curves facing away from the viewer;

3 : Detail oblique view of one of the partial levers of the double intermediate lever according to the invention of the valve lifting device 1 ; the driven tread of the partial lever with its working curve facing the viewer;

4 : Side view of a known valve lift device for variable valve control, which can be upgraded by retrofitting with the actuating means according to the invention in a second and third embodiment of a valve gear according to the invention.

In the different embodiments are similar acting, similarly designed and similar Objects have been provided with the same reference numerals, although they may differ in detail from each other.

A first embodiment of a valve lift of a variable valve drive device 8th which is a first embodiment of an actuating means according to the invention 1a . 1b is in 1 shown. The valve drive device 8th uses the invention in the form of a double fork lever 111 ( 2 ) as a double intermediate lever or as a fork intermediate lever, which a first and a second actuating means or intermediate lever 1a and 1b includes.

The present invention can be implemented with variable and fully variable valve trains known manner. The valve drive device 8th serves here for the variable valve lift adjustment of two gas exchange valves 7a and 7b For example, two intake valves of a cylinder. It has a rotatable camshaft as usual 9 and a likewise rotatable eccentric shaft 10 on, which cause the desired rotational or rotational oscillations of the individual valve train components. The eccentric shaft 10 has a first eccentric 11a and a second eccentric 11b on, which can rotate independently. Each of the eccentrics 11a . 11b causes the operation of an intermediate lever 1a respectively. 1b , where the intermediate lever 1a and 1b on a common axis 223 sit equipped with lateral stop fasteners. The axis 223 is about its longitudinal axis or pivot axis 222 rotatably mounted. The intermediate lever 1a is about a first axis point 2a , the intermediate lever 1b around a second axle point 2 B pivotable, with the first intermediate lever 1a a first output lever 6a and the second intermediate lever 1b a second output lever 6b actuated. The output lever 6a actuates a first gas exchange valve 7a , The second output lever 6b actuates a second gas exchange valve 7b , Because the following is true for both the first intermediate lever 1a as well as for the second intermediate lever 1b applies, the suffixes a and b, which should facilitate the separation of the parts of the individual lever, where confusion is not to be feared, omitted in the sequence.

The intermediate lever 1 is pivotable about an axis point 2 displaced. He has at its lower an output lever 6 facing side a driven tread 3 on which the output lever 6 during operation of the valve train 8th actuated.

The lever is formed in the first embodiment as a double fork lever or as a double intermediate lever, which is particularly in 2 can be clearly seen.

Accordingly, here are also two partial pivoting lever 1a and 1b of the double fork lever 1 available.

The actuating means 1a and 1b are each designed as a pivot lever. Each of these pivot levers 1a . 1b actuates the gas exchange valve assigned to it as an intermediate lever indirectly via an output lever assigned to it.

The swivel levers 1a . 1b of the fork intermediate lever 111 each have recesses 23 for reducing the mass inertia, in particular for reducing the moment of inertia by that through the axle point 2 extending pivot axis 222 of a lever. The recesses may be formed in the form of perforations. They can also be in the form of hollows 25 be educated. Here are located on each opposite the driven tread back of a partial lever two oval recesses 23 incorporated ( 2 ).

In the 2 not completely visible) output treads 3a and 3b are each on a web-like, in the field of working curves 18a and 18b formed in the longitudinal direction converging projection. One of the partial pivot levers is in 3 so shown that its output tread 3 facing the viewer and thus clearly visible. The working curve 18 is shown by dashed lines. In 3 and in the further description, the suffix a or b differentiating between the partial levers is omitted for the sake of simplicity. The further description therefore applies, unless expressly stated otherwise, for each of the two partial levers or also for embodiments which are equipped with individual levers.

According to the invention is the driven tread 3 as adjustable working curve 18 designed. It is at least partially rejuvenated ( 3 ).

Two (in 1 and 2 not visible) sections 4 . 5 of which one is a wider, in particular curved section 4 is, to which a narrower section 5 connects, determine the longitudinal orientation of the working curve 18 located at the bottom, from the axis point 2 located furthest away ( 3 ). Preferably, by pivoting the actuating means 1 a change in the position of the working curve 18 allows in the longitudinal direction. This is the attached output lever 6 , here in the form of a rocker arm, at another point on the working curve 18 in contact, especially in line contact. The transition of the first section 4 to the second section 5 is shaped laterally rounded in the transition area.

The actuating means 1 is thus formed in the first embodiment as an intermediate lever, on the output side of the rocker arm 6 (Acc. 1 ) is attachable, via which a gas exchange valve 7 is operable. Furthermore, the lever is designed as a double lever.

The actuating means 1 is based on its pivot axis 222 designed as balanced as possible with regard to its mass distribution. This is considered individually for each partial lever and also considered as a double lever as a whole for the execution.

The actuating means 1 has at least one recess 23 on. Under recess is in this context in particular a perforation 24 or a cavity 25 to understand. The cross section of the recess 23 . 24 . 25 may be drop-shaped or oval, for example. He could also be circular. In particular, it is advantageous if a perforation 24 or a cavity 25 by the actuating means 1 is formed extending therethrough. It may be convenient, a the cross section of the cavity channel 24 . 25 along the longitudinal extension of the channel with changing, in particular tapered, that is to say shrinking, cross-sectional area. The first embodiment of the actuating means 1 has three different shapes of recesses. in particular, the recesses 23 and the perforations 24 here oval in cross-section. The caves 25 are here drop-shaped in cross section.

The perforations 24 and the caves 25 each run through the actuating means 1 therethrough. Looking at that in 3 visible from a perforation 24 and a cavity 25 formed recess vault closer, so is clearly along the longitudinal extent of the cavity channel changing, in particular of the cavity 25 for piercing 24 Tapered cross section tangible.

The recesses 23 . 24 . 25 serve to reduce the mass inertia, in particular to reduce the moment of inertia by the point of the axle 2 extending pivot axis 222 ,

The at least one recess 23 or perforation 24 or cavity 25 limiting surface edge portions 54 extend at least partially predominantly parallel to the surface edge portions 54 lie closest the outer edge contour sections 55 of the actuating means 1 , A lever designed in this way 1 has low weight and thus reduced inertia.

If in this context of surface edges is mentioned, so are those particular self-contained and thus forming a window curves or surface areas to understand the exit or entry of a recess 23 or a perforation 24 or a cavity 25 from or into the actuator body 224 line. Surface edges can obviously be divided into sections along their course.

If in this context of outer edge contours the speech is, so are the contours of edges of the actuator to understand, based on the actuator body outboard are and along the two surface portions of the actuator body in the form of a kink or a particular chamfered rounding merge. Outside edge contours can obviously also be divided into sections.

How out 3 As can be seen, there is necessarily always exactly one outer edge contour section 55 that a certain surface edge section 54 a certain recess 23 . 24 . 25 is closest.

Particularly preferred is the design of the first embodiment of the actuating means 1 in which several by the actuating means 1 passing through each other inside the actuating means 1 intersecting or cutting perforations 24 or cavity channels 25 in the actuator 1 are incorporated. The first embodiment of the actuating means 1 has two contiguous recess vault. Each of these recess part vault is of a perforation 24 and a cavity 25 , which merge into each other, formed. You are here by a the strength and rigidity of the actuator body 224 supporting center wall 56 separated from each other. It is conceivable and possible the middle wall 56 also to provide, for example, with a perforation, to further save weight. However, it should be noted that the cavity of the actuator body 224 are limited by the required strength and rigidity of the actuating means. The design of the middle part of the lever as a double-T-carrier is particularly encouraging. Becomes a section of the outer wall contour section 55 over the middle wall 56 , behind or below the cavity 25 lies, until in the opposite outer surface 52 placed, then results in a double-T-beam in the side profile. The lever is in relation to the middle wall 56 symmetrically constructed. The person skilled in the art is immediately understandable that he dimensionally sufficient material to the actuating means, ie, must interpret the recesses accordingly, so that the above-mentioned accelerations do not lead to dysfunctional deformation, be they elastic or even plastic nature.

The driven tread 3 is in the first embodiment on a web-like, in the working curve 18 in the longitudinal direction of the wider, here lobe-shaped section 4 to the narrower section 5 formed towards converging extension. The extension is in the narrower section 5 Horny from the vaulting surface of the wider section 4 striving away and trained from her ascending.

The extension has a rounded tip 53 on. He covers on his from the wider section 4 turned aside, beyond the narrower section 5 and beyond the top 53 a third section 50 , The third section 50 goes into a pedestal widening towards its base 51 over and supports itself by means of the pedestal 51 on an outer surface 52 of the actuating means 1 from. The web-like extension runs over the third section 50 expanded in the central body 224 of the actuating means 1 into it. Here is the pedestal 51 integral with the outer surface 52 educated. One can see the entire extension in the area of the second and third section 5 . 50 designate nose or nose-shaped. This design results in a particularly light, yet solid and rigid structure.

Along the longitudinal direction of the working curve 18 is a vault of the wider section 4 educated. This is for the correct function of the lever 1 required. Here is the output tread 3 in the area of the wider section 4 normal to the working curve 18 across the entire width of the first section 4 Moreover, just trained. The curvature serves the variable or fully variable adjustability of the valve train 8th ,

However, it is also conceivable and possible, the shape of the surface of the driven tread 3 with regard to its longitudinal extent, so that it is at least similar to the shape of the surface of a rail, such as a railroad track. As a result, even more mass reduction can be achieved. In another aspect, by reducing the line-contacting friction due to the additional transversal curvature of the rail surface, power consumption and vibration excitation by the valvetrain can be reduced.

The driven tread 3 points in longitudinal direction the working curve 18 between the wider section 4 and the narrower section 5 a zero lift section 49 on, which is as wide as the wider section 4 , In the zero-stroke section 49 is the working curve 18 related to the zero stroke section 49 each limiting transition areas to the sections 4 . 5 concave.

The working curve 18 points in the area between the wider section 4 and the narrower section 5 , in the transitional area of the zero-lift section 49 to the narrower section 5 a turning point. The steepness of the working curve 18 is in the inflection point compared to its steepness in the transition region of the zero lift section 49 to the wider section 4 formed larger.

The extension of the narrower section 5 normal to the working curve 18 In other words, the width of the section - measures in proportion to the extension of the wider section 4 normal to the working curve 18 half or less than half. The width ratio is preferably only one third or less.

The variable valve drive device according to the invention 8th has the actuating means according to the invention 1 or the double fork intermediate lever according to the invention 111 on.

The second embodiment is based on a known valve lift device for variable valve control ( 4 ). One from a camshaft 9 actuatable intermediate lever 14 is as a roller lever with a roller 15 and a backdrop role 16 formed, wherein the guide roller in operation on the driven tread 3 along the work curve 18 an output lever 6 rolls. To set a variable valve lift, the axle point becomes 2 of the intermediate lever 14 in a housing-fixed backdrop 21 shifted by an actuator (not shown). The position of the axle point 2 in the housing-strong backdrop 21 detected by a (also not shown) sensor. The feather 22 serves to return the intermediate lever 14 , By replacing the known role intermediate lever 14 by an inventive actuating means 1 is an inventive valve train 8th receive. The output lever 6 pivots about the pivot axis 222 ,

It is also conceivable and possible in contrast to the two previous embodiments, the output lever 6 - And not or not only the intermediate lever - according to the invention form as described above.

In such a third embodiment, two actuating means according to the invention are paired and their output surfaces cooperate in mutual line contact. The one actuating means actuates a gas exchange valve as a pan or rocker arm 7 directly, the other actuator operates as an intermediate lever the gas exchange valve 7 indirectly.

The formation of the output surface 3 can be as a pan-shaped or at least in the front first section 4 be described as a flap-like. The rear second section 5 serves the regular lifting operation.

It is conceivable and possible the recesses 23 . 24 . 25 using variable geometries to design complex recess vaults. In particular, geometries with honeycomb-shaped or honeycomb recessing, excavating or lattice structures, for example with in particular symmetrical hexagonal honeycombs, similar to honeycombs, are conceivable and possible. Furthermore, it is conceivable and possible to manufacture the entire actuating means or at least parts thereof from nano-honeycomb structures, such as, for example, carbon nanotubes. Due to the 135 times better ratio of tensile strength to density than for steel, carbon nanotubes have superior mechanical properties that can be used to advantage in the general inventive concept described herein. By means of an inventive, in particular honeycomb-shaped hollowing out of an actuating means produced from a molecular nanotube material, such as carbon nanotubes, the mass reduction and the reduction of the mass moment of inertia, as well as the mass balance, can be advanced extremely advantageously.

To One aspect becomes an intermediate lever of a fully variable valve train particularly light, but sufficiently strong mechanically. According to another aspect, the invention is characterized that a mass balance and mass reduction in the areas the lever has been created for the functioning of the lever thinner, weak, delicate or graceful can be interpreted. The adapted in the material volume Lever of a fully variable valve train is so fluid designed that it can also be produced by a sintering process.

1

actuating means

1a

first actuating means

2a

second actuating means

3a

axis point

4a

first axis point

5a

second axis point

6a

Output tread

7a

first Output tread

8a

second Output tread

9a

first wider section

10a

second narrower section

11a

output lever

12a

first output lever

13a

second output lever

14a

Gas exchange valve

15a

first Gas exchange valve

16a

second Gas exchange valve

17a

Valve drive device

18a

camshaft

19a

eccentric shaft

20a

eccentric

21a

eccentric

22a

Role intermediate lever

23a

role

24a

setting role

25a

working curve

26a

first working curve

27a

second working curve

28a

Solid housing scenery

29a

feather

30a

recess

31a

perforation

32a

cavity

33a

Nullhubabschnitt

34a

third section

35a

base

36a

outer surface

37a

top

38a

Surface edge section

39a

Outer edges of contour section

40a

center wall

41a

Fork intermediate lever

42a

swivel axis

43a

axis

44a

Actuator body

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 10261304 A1 [0005, 0009]
• - DE 60305981 T2 [0006]
• - DE 10218026 A1 [0007]
• - WO 2004088094 A2 [0009]
• - DE 102004003327 A1 [0009]

Claims (17)

Actuating means ( 1 ), in particular intermediate, pivoting, towing, oscillating or rocker arms, preferably in the form of a double lever, for a valve train of an internal combustion engine, in particular for the indirect actuation of at least one gas exchange valve ( 7 ), with a driven tread ( 3 ), in particular pivotable about an axis point ( 2 ) is displaceable, characterized in that the output tread ( 3 ) as an adjustable working curve ( 18 ) is configured, which is formed at least partially tapered. Actuating means ( 1 ) according to claim 1, characterized in that the driven tread ( 3 ) a wider, in particular arched, first section ( 4 ), to which a second, narrower section ( 5 ). Actuating means ( 1 ) according to claim 2, characterized in that the two sections ( 4 . 5 ) the longitudinal orientation of the working curve ( 18 ), which are located at the lowest, from the 2 ) farthest side, preferably by pivoting the actuating means ( 1 ) a change in position of the working curve ( 18 ) is made possible in the longitudinal direction, whereby a to be mounted further output lever ( 6 ), such as tilting or pivoting levers, at another point on the working curve ( 18 ) comes into contact, especially in line contact comes. Actuating means ( 1 ) according to one of the preceding claims, characterized in that the actuating means ( 1 ) is designed as an intermediate lever, on the output side, a pivoting or rocker arm ( 6 ) can be attached, via which a gas exchange valve ( 7 ) is operable. Actuating means ( 1 ) according to one of the preceding claims, characterized in that the actuating means ( 1 ) is designed as a pan or rocker arm, which at least one gas exchange valve ( 7 ) directly operated. Actuating means ( 1 ) according to one of the preceding claims, characterized in that the actuating means ( 1 ) at least one recess ( 23 ) for reducing the mass inertia, in particular for reducing the moment of inertia about that by the axis point ( 2 ) running pivot axis ( 222 ), having. Actuating means ( 1 ) according to claim 6, characterized in that the at least one recess ( 23 ) limiting surface edge portions ( 54 ) at least partially predominantly parallel to, the surface edge portions ( 54 ), the outer edge contour sections ( 55 ) of the actuating means ( 1 ). Actuating means ( 1 ) according to claim 6 or 7, characterized in that several by the actuating means ( 1 ) extending therethrough, in particular in the interior of the actuating means ( 1 ) intersecting or cutting recesses ( 23 ) in the actuating means ( 1 ) are incorporated, which in the interior of the actuating means ( 1 ) form one or more contiguous recess vault. Actuating means ( 1 ) according to one of the preceding claims, characterized in that the driven tread ( 3 ) on a web-like, in the working curve ( 18 ) in the longitudinal direction of the wider, in particular lobe-shaped, section ( 4 ) to the narrower section ( 5 ) converging towards extension, which at least in the narrower section ( 5 ) Horn-shaped from the vault surface of the wider section ( 4 ) wegstrebend and formed from her ascending. Actuating means ( 1 ) according to claim 9, characterized in that the extension a particular rounded tip ( 53 ) and on its from the broader section ( 4 ) away from the narrower section ( 5 ) and beyond the top ( 53 ) a third section ( 50 ), which in a towards its base widening base ( 51 ) and by means of the base ( 51 ) on an outer surface ( 52 ) of the actuating means ( 1 ), the base ( 51 ) in particular in one piece with the outer surface ( 52 ) is trained. Actuating means ( 1 ) according to one of the preceding claims, characterized in that the curvature of the wider section ( 4 ) along the longitudinal direction of the working curve ( 18 ) is formed and in particular the driven tread ( 3 ) in the area of the broader section ( 4 ) normal to the working curve ( 18 ) at least in the working curve ( 18 ) immediately formed areas is formed. Actuating means ( 1 ) according to one of the preceding claims, characterized in that the shape of the surface of the driven tread ( 3 ) is at least similar in shape to the surface of a rail, such as railroad track, with respect to its longitudinal extent. Actuating means ( 1 ) according to one of the preceding claims, characterized in that the driven tread ( 3 ) in the longitudinal direction of the working curve ( 18 ) between the wider section ( 4 ) and the narrower section ( 5 ) a particularly equally wide zero stroke section ( 49 ) like the wider section ( 4 ), in which the Ar working curve ( 18 ) relative to the zero lift section ( 49 ) each limiting transition areas to the sections ( 4 . 5 ) is concave. Actuating means ( 1 ) according to one of the preceding claims 2 to 13, characterized in that the working curve ( 18 ) in the area between the wider section ( 4 ) and the narrower section ( 5 ), in particular in the transition region of the zero lift section ( 49 ) to the narrower section ( 5 ) has a turning point, in particular the steepness of the working curve ( 18 ) in comparison to its steepness in the transition region of the zero-stroke section ( 49 ) to the broader section ( 4 ) is larger. Actuating means ( 1 ) according to one of the preceding claims 2 to 14, characterized in that the extension of the narrower section ( 5 ) normal to the working curve ( 18 ) in proportion to the extension of the broader section ( 4 ) normal to the working curve ( 18 ) up to half, preferably up to a third. Double fork lever ( 111 ), in particular as a double intermediate lever, for a valve drive of an internal combustion engine comprising a first and a second actuating means ( 1a . 1b ) according to one of the preceding claims, characterized in that the two actuating means ( 1a . 1b ) on a common axis ( 223 ) are equipped with lateral stop fasteners, so that each of the actuating means ( 1a . 1b ) about the same pivot axis ( 222 ), but the first actuating means ( 1a ) at a first axis point ( 2a ) and the second actuating means ( 1b ) at a second, from the first axis point ( 2a ) axially spaced axis point ( 2 B ), is pivotable. Variable or fully variable valve train device ( 8th ) with at least one actuating means ( 1 ), in particular with a double fork lever ( 111 ) according to claim 16, characterized in that the actuating means ( 1 ) is designed according to one of the preceding claims.