DE10226822A1 - Motor vehicle internal combustion engine valve rocker has outer arm with relatively pivotable inner arm to adjust valve timing - Google Patents

Abstract

The motor vehicle internal combustion engine rocker has an outer arm (2) formed by a pair of levers (3) and an inner arm (4) between these, which is relatively pivotable to them. The free ends of the outer arms form an abutment (8) for the end of the valve stem. The inner arm is pivoted on an axis (24) offset from the outer arm axis and carrying a cam follower (11,12).

Description

Field of the invention

The invention relates to a drag lever a valve train of an internal combustion engine, the different valve lifts for at least a gas exchange valve is switchable, with an outer lever, between the two arms one to this relatively pivotable Inner lever is positioned, which with the outer lever via one or more coupling means is connectable, the outer lever at a base in the area of its one closed end a facility for the gas exchange valve has, the rocker arm at the bottom in Section of its one end opposite end of a complementary surface for a support element has and wherein at an upper side of the finger lever cam starting means are applied.

Such a switchable drag lever is from the DE-OS 27 53 197 previously known. This also consists of an outer lever which includes a relative to this pivotable inner lever. As a coupling means a pawl is provided, which can be moved over a complex, electromagnetically acted linkage. It is stated that the rocker lever disadvantageously requires too much installation space, in particular in the direction of the cylinder head. Furthermore, the ratchet mechanism relatively far away from the pivot center unnecessarily increases the mass moment of inertia. The drag lever is also comparatively relatively complicated, so that is to be expected here with increased manufacturing costs. In addition, a valve lift friction unnecessarily increasing Gleitabgrift the cam lift is provided.

Task of invention

The object of the invention is therefore to to provide a drag lever of the aforementioned type, in which the cited disadvantages are eliminated.

Summary the invention

According to the invention, this object is achieved solved, that foreign and inner lever forked are designed open, with the inner lever with the dome-shaped indentation trained complementary surface for the support element at the opposite End provided and pivotally movable between the ends of the Poor of the outer lever is attached, wherein above or in the area of the complementary surface separate pipe section is mounted transversely in the inner lever, which on both sides adjacent separate sleeve sections in the outer lever in a rotational position from outside to Inner lever is aligned, wherein in at least one of the sections of the at least one coupling means extends, which is over from supporting through the complementary area and the pipe section conductive hydraulic fluid for coupling or decoupling purpose is relocatable.

Thus, a drag lever is proposed at which eliminates the disadvantages mentioned above with simple means are. Due to the forked shape open design of the external and inner lever has the rocker arm altogether only a relative low weight. In addition, leaves the exterior and Make inner lever relatively easy. Here is in concretization proposed the invention, both elements of a sheet metal material thermoforming technology.

Characterized in that as a coupling agent across displaceable piston or slide are proposed, which expediently in a tube or sleeve section above the dome-shaped Forming run, on the one hand, the moment of inertia due the arranged at the fulcrum coupling agent is not unnecessarily increased. on the other hand let the tube or sleeve section very easily retrofitted in Install the cam follower.

Characterized in that the coupling means according to the proposal with hydraulic means be supplied, which from the support element by the complementary surface in the Tube section is conductive, is to act on the coupling agent no additional Space, for example, lying on the side, needed.

In concretization of the invention Although it is proposed, the coupling means in Entkoppelrichtung hydraulically and in their coupling direction mechanically via the force of compression springs to act on, but also conceivable is a hydraulic displacement the coupling agent in their coupling and a return displacement in their Entkoppelrichtung. Likewise, it is conceivable and intended, the coupling means in their two Apply displacement directions hydraulically or others suitable forms of application such as magnetic, electromagnetic etc. to apply.

According to a particularly preferred Specification of the invention, it is proposed only the Inner lever with cam starting means to provide. Thus lies one Drag lever, which is preferably completely decoupled from the cam lift. However, it is also conceivable, the outer lever with wide ren cam start means to be provided so that at slightly modified drag lever also generates different valve strokes can be.

Characterized in that the axis is made for pivotally mounting the inner lever relative to the outer lever at the same time as an axis for the role as a cam starting means, a separate formation of one of the aforementioned elements is unnecessary. Due to the role as a cam starting means in the inner lever is another contribution towards Mi Nimierung the valve drive work done.

The rocker arm according to the invention can also be referred to as "articulated lever", because in Abschaltfall (decoupling of the coupling agent) in about Centrally arranged in the drag lever role a dipping motion in Direction cylinder head performs, the outer lever in the area of the opposite End also pivoted in the direction of the cylinder head.

Instead of the proposed piston or slider in the pipe section or the sleeve sections can also similar or other coupling means such as rollers, wedges, pins, etc. provided his.

Due to the proposed interference fit for fixing the sleeve sections or the pipe section in the external or inner lever can be on additional security measures be waived. The press fit is easy to make. However, it is also conceivable attachment via screwing, Welding, Caulking etc.

A particularly advantageous embodiment of Invention is the subject of another subclaim. Therefore should the pipe section axially outside flush with side surfaces from arms of the inner lever, with the arms on the Upper side project in the region of the pipe section dachsegmentartig the side surfaces. As a result, an in each case inwardly projecting region of the sleeve sections of the outer lever to strike undersides of the pipe section. Thus, a simple situation assignment of the pipe section to the sleeve sections created, so that in the cam base circle, the sliding movement of the Coupling agent can be easily realized. On the other hand is in Continuous decoupling mode of the finger lever an easy limit the Verschwenkweges the outer lever in its backward movement realized relative to the inner lever at the expiring cam edge.

Furthermore, it is the subject of Invention to arrange a total of two slides in the pipe section, the axially outside act on a respective piston of the respective sleeve section. Thus lies a slide package with a total of four separate components, wherein in the decoupling the paket halves axially away from each other. Of course, also coupling measures conceivable and intended, in which, for example, a package with a total of two or three separate sections is realized, which for the coupling purpose in one and for the Entkoppelzweck shifted in the other direction in total become.

Due to the central admission the slide with hydraulic fluid via an opening arranged in the complementary surface is unnecessary Zuleitmaßnahmen on hydraulic means, such as longitudinally on the finger lever running channels o. Ä.

Finally, it is suggested guide cheeks for the Gas exchange valve in one piece as an extension of the side walls of the outside lever train and then on the underside of the outer lever to bend. This is particularly advantageous if the two Lever parts made of a sheet metal material in a forming process are.

Short description the drawing

• 1 eine räumliche Darstellung des erfindungsgemäßen Schlepphebels;
• 2 eine Schnittansicht quer durch den Schlepphebel im Bereich der Koppelmittel;
• 3 eine räumliche Darstellung des Außenhebels und
• 4 eine räumliche Ansicht auf den Innenhebel mit Rohrabschnitt und Nockenanlaufmittel.

The invention is suitably explained in more detail with reference to the drawing. Show it:

• 1 a spatial representation of the finger lever according to the invention;
• 2 a sectional view transversely through the cam follower in the region of the coupling means;
• 3 a spatial representation of the outer lever and
• 4 a spatial view of the inner lever with pipe section and Nockenanlaufmittel.

Full Description of the drawing

The 1 shows a drag lever 1 , which can also be referred to as "articulated lever" (see also the introduction to the description) 1 consists of a fork-shaped outer lever 2 , between its two parallel arms 3 one of these relatively pivotable inner lever 4 with arms 17 (see also further figures) is arranged.

The outside lever 2 is in the area of its one closed end 7 at a bottom 6 with a facility 8th provided for a gas exchange valve. The attachment 8th is laterally bounded by guide cheeks 25 as an extension of the arms 3 are made and on the bottom 6 were bent. Preferably, the outer and inner levers 2 . 4 made of sheet metal in a deep-drawing process.

The outside lever 2 has in the area of an opposite end 9 two opposite shots 15 , In every shot 15 is a sleeve section 14 pressed. A floor 22 each sleeve section 14 is arranged axially on the outside and has a perforation 23 as air outlet.

In the uncoupling state of the rocker arm 1 is in each sleeve section 14 a piston 5a as a component of coupling agents 5 arranged. These pistons 5a protrude in the aforementioned Entkoppelzustand to a maximum of a separation surface between the outer and inner lever 2 . 4 , Axially inwards are the pistons 5a about the force of a compression spring 21 subjected to axially outward on a floor 22 the corresponding sleeve section 14 supported.

Furthermore, the skilled person 2 see that the sleeve section 14 axially inwardly over a corresponding inner sidewall of the respective arm 3 also available.

The inner lever 4 is like the outside lever 2 fork-shaped open. He walks with his arms 17 inside the arms 3 of the outer lever 2 , He has to one end 7 one as roller bearing produced cam starting means 12 , This is on an axis 24 stored, which through corresponding holes in the arms 17 guided and in the arms 3 of the outer lever 2 is attached. Thus, on the one hand, a pivot center of the inner lever 4 opposite the outside lever 2 manufactured and at the same time has the pivot center still on a top 11 the aforementioned cam starting means 12 ,

Furthermore, it is off 1 a not-to-explain Lost-motion spring 26 recognizable, the on from the outside lever 2 outstanding axle stump is attached and on the one hand against tops of the arms 3 and on the other hand on the inner lever 4 acts in a manner familiar to the person skilled in the art.

In the area of the opposite end 9 is how closer 2 shows a pipe section 13 applied. This one is in opposite shots 16 the poor 17 of the inner lever 4 attached. The pipe section projects beyond this 13 axially outside not outer surfaces of the corresponding arms 17 , In the area of its transverse center plane is the pipe section 13 on the formed as ka lottenförmige indentation complementary surface 10 additionally stored.

Inside the pipe section 13 are in the coupling state of the finger lever shown here 1 two adjoining slides with their insides 5b as another component of the coupling agent 5 arranged. These sliders 5b can be displaced axially outwardly via hydraulic means, which, starting from the drawing not disclosed support member, through an opening in the complementary surface 10 and another opening in the pipe section 13 is conductive in these.

In the area of the top 11 is the pipe section 13 dachsensegment-like of components of the arms 17 towered over (see also 4 ). On bottoms 18 This projecting sections lies or suggests in the coupling or decoupling case in the base circle passage of the cam of the corresponding sleeve portion 14 of the outer lever 2 on. Thus, an excellent positional allocation of the sleeve sections 14 to the pipe section 13 realized and the coupling agent 5 can be relocated easily.

As you can see, the pipe section is 13 immediately above the complementary surface 10 arranged for the support element. This has a particularly positive effect on the mass moment of inertia of the finger lever 1 out.

The separately manufactured pipe section 13 and the separate sleeve sections 14 Manufacturing technology are also very easy to control and guarantee the ease of formability producibility of the outer and inner lever 2 . 4 ,

1

cam follower

2

external lever

3

poor

4

internal lever

5

coupling means

5a

piston

5b

pusher

6

bottom

7

The End

8th

investment

9

The End

10

complementary surface

11

top

12

Cam nose means

13

pipe section

14

sleeve section

15

admission

16

admission

17

poor

18

bottom

19

Area

20

pressure chamber

21

compression spring

22

ground

23

perforation

24

axis

25

guide cheek

26

Lost-motion spring

Claims (10)

Drag lever ( 1 ) of a valve drive of an internal combustion engine, which is switchable to different valve lifts for at least one gas exchange valve, with an outer lever ( 2 ), between its two arms ( 3 ) a to this relatively pivotable inner lever ( 4 ) which is connected to the outer lever ( 2 ) via one or more coupling agents ( 5 ) is connectable, wherein the outer lever ( 2 ) on a lower side ( 6 ) in the region of its one closed end ( 7 ) an annex ( 8th ) for the gas exchange valve, the drag lever ( 1 ) on the bottom ( 6 ) in the section of its one end ( 7 ) opposite end ( 9 ) a complementary surface ( 10 ) has a support element and wherein on an upper side ( 11 ) of the rocker arm ( 1 ) Cam starting means ( 12 Are applied), characterized net gekennzeich that the outer and inner lever ( 2 . 4 ) are designed fork-shaped open, wherein the inner lever ( 4 ) with the formed as a dome-shaped indentation complementary surface ( 10 ) provided for the support element at the opposite end and between the ends ( 7 . 9 ) pivotable on the arms ( 3 ) of the outer lever ( 2 ), wherein above or in the region of the complementary surface ( 10 ) a separate pipe section ( 13 ) across the inner lever ( 4 ), which is adjacent to both sides separate sleeve sections ( 14 ) in the outside lever ( 2 ) in a rotational position from outer to inner lever ( 2 . 4 ) is aligned, wherein in at least one of the sections ( 13 ) the at least one coupling agent ( 5 ), which extends over the supporting surface by the complementary surface ( 10 ) and the tube section ( 13 ) conductive hydraulic fluid for coupling or decoupling purpose is displaced. Cam follower according to claim 1, characterized in that the sections ( 14 . 13 ) in corresponding recordings ( 15 . 16 ) of the outer and inner lever ( 2 . 4 ) fixed in place via a connection such as a press fit. Drag lever according to claim 1, characterized in that the pipe section ( 13 ) axially outboard flush with side surfaces of arms ( 17 ) of the inner lever ( 4 ), the arms ( 17 ) at the top ( 11 ) in the region of the pipe section ( 13 ) dachsensegment like the side surfaces protrude, on whose undersides ( 18 ) an axially inwardly projecting area ( 19 ) of the sleeve sections ( 14 ) experiences a stop. Drag lever according to claim 1, characterized in that in the pipe section ( 13 ) a total of two slides ( 5b ) as coupling agent ( 5 ) run in the coupling state with their inner end faces centered in the pipe section ( 13 ) abut each other, wherein axially on the outside of each slide ( 5b ) a piston ( 5a ) as a further coupling agent ( 5 ), which in the coupling state in each case a separating surface between the outer and inner lever ( 2 . 4 ) and in the uncoupling state over the displaced up to the separating surface slide ( 5b ) in the respective sleeve section ( 14 ) is shifted. Drag lever according to claim 4, characterized in that the slides ( 5b ) and the pistons ( 5a ) axially outwardly in its Entkoppelstellung on the through the complementary surface ( 10 ) in a pressure chamber ( 20 ) in front of the inner end faces of the slides ( 5b ) directly conductive hydraulic means are packet-like displaced, wherein a return displacement in their Kop pelstellung over on the piston ( 5a ) axially inwardly acting compression springs ( 21 ) which can be produced on floors ( 22 ) of the sleeve sections ( 14 ) are axially supported outside. Drag lever according to claim 6, characterized in that the trays ( 22 ) with at least one perforation ( 23 ) are provided. Drag lever according to claim 1, characterized in that the pipe section ( 13 ) on the complementary surface ( 10 ) experiences a support. Drag lever according to claim 1, characterized in that for the pivotable attachment of the inner lever ( 4 ) on the outer lever ( 9 ) an axis ( 24 ) provided at both ends in bores of the arms ( 3 ) of the outer lever ( 2 ) is arranged, wherein only the inner lever ( 4 ) with the cam starting means ( 12 ) and between arms ( 17 ) of the inner lever ( 4 ) a rotatable roller as cam starting means ( 12 ) on the axis ( 24 ) runs. Drag lever according to claim 1 or 9, characterized in that the system ( 8th ) for the gas exchange valve at the bottom ( 6 ) laterally each of a guide cheek ( 25 ), which is a one-piece extension of the corresponding arm ( 3 ) of the outer lever ( 2 ) are formed and on the underside ( 6 ) run bent. Drag lever according to claim 1, characterized in that the outer and inner levers ( 2 . 4 ) are made in one piece from a deep-drawn sheet metal material.