DE102006061296A1 - Switchable drag lever for a valve train of an internal combustion engine u. Method for mounting a switchable rocker arm - Google Patents

Abstract

Switchable drag lever (1) for a valve train of an internal combustion engine, wherein the drag lever (1) consists of an outer lever (3) and between the arms (2) extending inner lever (4). The outer lever (3) is penetrated in its end region (5) by a transverse axis (6) on which the inner lever (4) with its legs (7) is mounted so as to be able to pivot relative to the outer lever (3). The levers (3, 4) are connected to each other via coupling means so that when coupling a large and decoupling a smaller valve lift is transmitted. The transverse axis (6) is at least surrounded by a torsion spring (13) as a lost-motion spring whose one end (14) against a stop (15) of the outer lever (3) and the other end (16) against a stop (17 ) of the inner lever (4) is tensioned. Furthermore, a method for mounting a switchable drag lever (1) is proposed.

Description

The The invention relates to a switchable drag lever for a Valve gear of an internal combustion engine, the drag lever off an outside lever and a running between the arms inner lever. The outside lever is penetrated in its end by a transverse axis, on the relatively pivotable to the outer lever of the inner lever with his thighs is stored. The levers are via coupling means with each other connected, that with coupling a large and with decoupling one transfer smaller or no valve lift becomes. At a bottom of the rocker arm is at a long-tail a facility for a gas exchange valve and at the other longitudinal end of a complementary surface for support against the cylinder head intended. The transverse axis is at least of a torsion leg spring as a lost-motion spring encircling one end against a stop of the outer lever and its other end clamped against a stop of the inner lever is. The invention further relates to a method for assembly a switchable rocker arm.

Background of the invention

Such a drag lever and such a method are out DE 10 2004 046 599 A1 known. There, at least one torsion spring is arranged on a transverse axis as a lost-motion spring. The torsion spring is mounted together with the transverse axis and the levers in an unstressed state, wherein one end of the torsion spring is applied to one of the stops on the outer or inner lever. The tensioning of the other end of the torsion leg spring takes place at the stop of the other lever. In the assembled state, the torsion leg spring bears with its one end on a connecting bracket formed as a stop of the arms of the outer lever. The other end of the torsion leg spring is stretched behind a stop on the inner lever. This stop is based on the end pieces of the inner lever and is designed as an inwardly bent extension.

adversely in this embodiment affects the fact that, to tighten the torsion leg spring at one of the stops on the inside or outside lever the free end of the torsion spring in the vertical and in the transverse direction or in the transverse direction and in the longitudinal direction thus in each case must be bent in two directions to this to bring concern to the respective attack. Hereby are at least two assembly forces are required to tension the torsion leg spring, the one in the vertical or in the longitudinal direction and the other acting in the transverse axis direction on the free end of the torsion leg spring got to. As a result, the assembly process is complicated and expensive, in particular a machine clamping of the torsion leg spring is more difficult.

Farther This can be done on the designed as a stop on the inner lever extension fitting taut end of the torsion leg spring to the inside open end of the extension moved by the axial forces acting in operation in the transverse axis direction or bent. Therefore, in this embodiment, additional activities required to remove the cocked torsion spring against disassembly to secure during operation.

adversely is further in this embodiment, that an additional connecting brackets as a stop on the outer lever must be provided, in addition to the rocker arm the top is enlarged. Of Further leads intended as a stop extension on the end pieces of Inner lever to an extension of the rocker arm in the longitudinal direction.

Summary of the invention

Of the The invention is therefore based on the object, a switchable drag lever in terms of its structure so that it is easier, cost-effective and more reliable to assemble. It is another object of the invention to provide a method for simple, inexpensive and reliable installation of a switchable rocker arm to create.

According to the invention Task solved by that guide means for tensioning the other end of the torsion leg spring on a stop are provided of the inner lever.

alternative this task is solved by that for clamping the other end of the torsion leg spring over a attacking there first force vector and guide means against the stop is stretched on the inner lever.

By the inventive design of Toggle lever in the transverse axis can the torsion leg spring simple, inexpensive and be mounted safely.

Advantageously, according to the invention guide means for clamping the other end of the torsion leg spring are provided on a stop of the inner lever. The guide means allow guiding and tensioning of the torsion leg spring at the same time. As a result, by applying a single mounting force, the free end of the drum spring against a stop on the inner lever can be stretched. As a result, unnecessary further Montageschrit te be avoided for clamping the torsion leg spring. At the same time, the rotary leg be clamped reliable operation in a single assembly step on the guide means according to the invention.

In an inventive embodiment of the Toggle lever is the one end of the torsion spring against a palm a facility for the gas exchange valve on the outer lever curious; excited. By applying the one end of the torsion leg spring to the palm the plant for the gas exchange valve can easily turn the torsion leg spring be pre-assembled in unstressed condition. At the same time additional Stop devices on the outer lever avoided and the drag lever is not unnecessarily increased.

advantageously, are the guides and the stop on the inner lever on the inside of a leg of Inner lever arranged. The formation of the attack on an inside the leg of the inner lever offers the advantage of an unnecessary increase in the Drag levers in the longitudinal direction or on the underside or upper side of the towing lever and so to reduce the required space volume of the finger lever.

In a further advantageous embodiment of the finger lever according to the invention for guiding and simultaneous clamping of the other end of the torsion leg spring is a draft with a lug surface and with a contact surface as a stop on at least one of the inner sides of the legs ( 7 ) of the inner lever is formed. The draft has on its upper side an inwardly inclined oblique approach surface and on its inner side an end face over which the free end of the torsion leg spring can be guided and bent. In this case, the free end of the torsion leg spring is biased by the resulting reaction force on impact of the draft angle both in the vertical and in the axial direction relative to the transverse axis. On its underside, the draft has an at least obliquely formed contact surface, under which the guided over the draft angle during clamping free spring legs can be created by simply snapping. The inventively provided draft serves thus for clamping the free end of the torsion leg spring as a guide and stop at the same time. As a result, the assembly is simplified for tensioning the torsion leg spring, in particular allows a simple and cost-effective mechanical assembly. In a single assembly step, the free end of the torsion leg spring can be tensioned by a attacking there single mounting force on the stop of the inner lever.

advantageously, is in the final assembled according to the invention Condition of the strained torsion spring the other end of the torsion leg spring both against the contact surface as well as stretched against the inside of the leg of the inner lever. in this connection the vertical spring force components bias the end of the torsion leg spring against the contact surface at the draft, while at the same time the axial spring force components the spring leg Press against the inside of the leg of the inner lever and Secure the tensioned torsion spring against disassembly during operation.

Advantageously, the of draft made in one piece with the inner lever

By the method provided according to the invention for mounting the finger lever mounting the same is simplified, more cost effective and more reliable.

advantageously, is provided according to the invention, that the other end of the torsion spring over a there attacking first force vector and over guide means is clamped against the stop on the inner lever. This is the uncovered end the torsion spring by guide means so guided, for example about a draft that by the application of a single assembly force at the free end, for example, by simply bending down the same, this brought to rest against the stop on the inner lever and reliable can be tightened. This will make the use of unnecessary further mounting forces and the implementation further assembly steps to the leadership or alignment of the free end for tensioning the torsion leg spring avoided. Furthermore, the process according to the invention neces sary only mounting force simply applied by machine be, for example by a stamp. This makes it possible to do that Clamping the torsion spring completely automated and inexpensive to perform. Further It is possible to use the guide the Drehschenkelffeder reliable on the stop on the inner lever to tense.

advantageously, In the pre-assembly step, the one end of the torsion leg spring in an untensioned state against an inner surface of a system for the gas exchange valve as a stop on the outer lever created. As a result, the pre-assembly of the sprocket spring in unstressed condition without additional Stop device on the outer lever done in a simple way.

In a further advantageous manner, for tensioning the other end of the torsion leg spring, a first force vector engages inwardly there to the transverse axis inwards in the direction of the underside of the finger lever. In an assembly step so can the free end of the torsion leg spring by a simple He bending down or pressing down on the guide means are clamped to the stop of the inner lever.

Of Another is advantageously provided according to the invention that for clamping the other end of the torsion spring on a stop on a the inner sides of a leg of the inner lever is tensioned. There arranged the stop on the inside of a leg of the inner lever is, the drag lever is not unnecessary longitudinally or vertically Direction enlarged.

In a concretization of the invention is further provided that for tensioning the other end of the torsion spring over one of draft on one of the inner sides of the legs of the inner lever in the direction guided and bent at the bottom of the rocker arm as well as at one contact surface the draft angle is brought to the concern. The inventively provided of draft at the same time as a guide and as a stop when tensioning the free end of the torsion leg spring. With the help of a single Mon day force in the shape of the free end the torsion spring attacking first force vector, for example by a simple bending down or pushing down, the free end of the Turning leg spring over the approach surface the draft angle guided and be bent. Here, the free end of the torsion leg spring due to the resultant at impact on the draft Mounting reaction force in both the vertical and in the axial direction biased relative to the transverse axis. By a simple snap the free leg of the torsion leg spring on the contact surface of the of draft be brought to the concern. This is the end of the torsion leg spring through the vertical spring force component against the contact surface on the of draft and by the axial spring force component against the inside of the leg the inner lever stretched. In this way, the assembly is facilitated and at the same time the axial spring force components secure the stressed one Torsion spring against disassembly during operation.

In an inventive embodiment of the Method, the tensioning of the other end of the torsion leg spring on a take place there attacking another second force vector. In this Variant is in support the assembly next to the first force vector another mounting force applied to the free end of the torsion spring. hereby is it possible, for example, through the attacking further second force vector during the tensioning of the torsion leg spring, especially when bending down the free end by the attacking first force vector to guide this or align. For example, in support of the Assembly of components with large Tolerance play, if necessary, the free spring leg with the help of second attacking force vector positioned over the draft become. It can be advantageously provided that the second force vector at the other end of the torsion leg spring in parallel acting on the transverse axis acting inwards. This way you can the free end of the spring during the tensioning of the torsion leg spring inwards into the drag lever depressed or be bent. This may cause a downward bending or depression of the led free end of the torsion spring in the transverse direction or be aligned.

In can advantageously all Procedural steps to be completed automatically.

in the preferred case of the arrangement of two torsion springs on the Transverse axis, can these are placed so that with respect to this transverse axis the free ends of the torsion springs are axially outward. That's it possible, the free ends by simply pressing down or bending over each one formed on the inner sides of the legs of the inner lever of draft to cock against a stop. So can inside and outside lever be easily clamped together reliable.

Brief description of the drawings

Further Features of the invention will become apparent from the following description and from the drawings, in which an embodiment of the invention is shown simplified. Show it:

1a - 1b Spatial view of a switchable rocker arm in preassembled condition with unstressed torsion springs ( 1a ) and after tensioning the torsion springs ( 1b )

2a - 2 B Top view of a switchable rocker arm in preassembled condition with unstressed torsion springs ( 2a ) and after tensioning the torsion springs ( 2 B )

3a - 3b Section AA of a switchable rocker arm in preassembled condition with unstressed torsion springs ( 3a ) and after tensioning the torsion springs ( 3b )

4a - 4b Spatial view of a switchable rocker arm in preassembled condition with unstressed torsion springs ( 4a ) and after tensioning the torsion springs ( 4b )

5a - 5b Spatial view of a Section BB of a switchable rocker arm in preassembled condition with unstressed torsion springs ( 5a ) and after tensioning the torsion springs ( 5 ).

Detailed description of the drawings

The 1a to 5a show a switchable drag lever 1 for a valve train of an internal combustion engine in preassembled state with unstressed torsion springs 13 , The rocker arm 1 has an outside lever 3 between his arms 2 an inner lever 4 pivots. The outside lever 3 is at an end area 5 from the transverse axis 6 protruding, being on the transverse axis 6 relatively pivotable to the outer lever 3 the inner lever 4 with its thighs 7 is stored. The levers 3 . 4 are connected to each other via coupling means, not shown, that when coupling a large and decoupling a smaller or no valve lift is transmitted.

At a bottom 8th of the rocker arm 1 is at one longitudinal end 9 a plant 10 mounted for a gas exchange valve, not shown. At the other longitudinal end 11 runs an indicated complementary area 12 for a support (for example a hydraulic support element) relative to a cylinder head.

The transverse axis 6 is from two torsion springs 13 as lost-motion springs inside the thighs 7 of the inner lever 4 enclosed. The inner lever 4 and the outside lever 3 be along with the on the transverse axis 6 located torsion springs 13 pre-assembled in their untensioned condition.

This will be the ends 14 the torsion bar springs 13 to the stop 15 of the outer lever 3 Simply put on without the torsion springs 13 be tense. The stop 15 gets through the inner surface 24 the plant 10 formed for the gas exchange valve and extends at the bottom 8th of the rocker arm 1 , As a result, the attachment of additional stop devices at the bottom 19 or top 18 or in the longitudinal direction of the outer lever 3 In addition, pre-assembly is simplified.

In the 1b to 5b is a switchable drag lever 1 after tensioning the torsion bar springs 13 shown.

On the insides 20 the thigh 7 of the inner lever 4 is one each as a stop 17 trained draft 21 attached, which on its upper side an inwardly inclined oblique approach surface 22 and an end face 25 and on its underside an obliquely formed contact surface 23 having. About the approach surface 22 and the frontal area 25 the draft angle 21 can the free ends 16 the torsion bar springs 13 be guided and bent to the bottom of the draft angle 21 under the contact surface 23 to be brought to the concern. For tensioning the torsion bar springs 13 become the free ends 16 about one at each end 16 engaging mounting force F1 vertical to the transverse axis 6 towards the bottom 8th of the rocker arm 1 acting, for example, by simply bending down or pressing down on the draft 21 guided ( 3a and 3b ). By the case when hitting the draft 21 resulting assembly reaction force become the ends 16 the torsion bar springs 13 both in the vertical and in the axial direction with respect to the transverse axis 6 biased. By simply snapping the free spring legs can 16 at the respective contact surface 23 the draft 21 be brought to the concern. Here are the ends 16 the torsion bar springs 13 by the vertical spring force components against the respective contact surface 23 at the draft angle 21 and by the axial spring force components against the insides 20 the thigh 7 of the inner lever 4 pressed. As a result, the assembly is facilitated and at the same time are the strained torsion springs 13 secured against disassembly during operation by the axially acting spring force components.

In the exemplary embodiment according to the invention, it is provided that a second force vector F2 in each case at the free ends 16 the torsion bar springs 13 attacks ( 2a ). In this particular variant of the method according to the invention, the second force vector F2 as an executive supports the tensioning of the torsion spring elements 13 by the first force vector F1. Since the second force vector F2 each at free ends 16 the torsion bar springs 13 parallel to the transverse axis 6 acting on the inside ( 2a ), while tensioning the torsion bar springs 13 the free ends 16 inside the rocker arm 1 be pressed or bent. In this way, can be guided or aligned in the axial direction by the attacking first force vector F1 in the axial direction by the attacking second force vector F2, the downward bending in the vertical direction.

The draft 21 are one-piece with the thighs 7 on their insides 20 the inner lever 4 formed.

1

cam follower

2

poor

3

external lever

4

internal lever

5

end

6

transverse axis

7

leg

8th

bottom

9

long side

10

investment

11

longitudinal end

12

complementary surface

13

Torsion spring

14

The End

15

attack

16

The End

17

attack

18

top

19

bottom

20

inside

21

of draft

22

approach surface

23

contact surface

24

palm

25

face

F1

first force vector

F2

second force vector

Claims (15)

Switchable drag lever ( 1 ) for a valve train of an internal combustion engine, wherein the drag lever ( 1 ) from an outer lever ( 3 ) and one between its arms ( 2 ) extending inner lever ( 4 ), the outer lever ( 3 ) in its end region ( 5 ) from a transverse axis ( 6 ) is penetrated on the relatively pivotable to the outer lever ( 3 ) the inner lever ( 4 ) with his thighs ( 7 ), the levers ( 3 . 4 ) are coupled together via coupling means so that when coupling a large and decoupling a smaller or no valve lift is transmitted and wherein the transverse axis ( 6 ) of at least one torsion spring ( 13 ) is embossed as a lost-motion spring whose one end ( 14 ) against a stop ( 15 ) of the outer lever ( 3 ) and its other end ( 16 ) against a stop ( 17 ) of the inner lever ( 4 ), characterized in that guide means ( 21 ) for tensioning the other end ( 16 ) the torsion leg spring ( 13 ) at the stop ( 17 ) of the inner lever ( 4 ) are provided. Drag lever ( 1 ) according to claim 1, characterized in that the one end ( 14 ) the torsion leg spring ( 13 ) against an inner surface ( 24 ) of a plant ( 10 ) for the gas exchange valve on the outer lever ( 3 ) as a stop ( 15 ) is tense. Drag lever ( 1 ) according to claim 1, characterized in that the guide means ( 21 ) and the stop ( 17 ) on the inside ( 20 ) of a thigh ( 7 ) of the inner lever ( 4 ) are arranged. Drag lever ( 1 ) according to claim 1 or 3, characterized in that for guiding and simultaneously clamping the other end ( 16 ) the torsion leg spring ( 13 ) a draft ( 21 ) with a contact surface ( 22 ) and with a contact surface ( 23 ) as a stop ( 17 ) on at least one of the insides ( 20 ) of the thighs ( 7 ) of the inner lever ( 4 ) is trained. Drag lever ( 1 ) according to one of claims 1 to 4, characterized in that the other end ( 16 ) the torsion leg spring ( 13 ) against both the contact surface ( 23 ) as well as against the inside ( 20 ) of the thigh ( 7 ) of the inner lever ( 4 ) is tense. Drag lever ( 1 ) according to claim 1 or 4, characterized in that the draft angle ( 21 ) in one piece with the inner lever ( 4 ) is executed Method for mounting a switchable drag lever ( 1 ) for a valve train of an internal combustion engine, wherein the drag lever ( 1 ) from an outer lever ( 3 ) and one between its arms ( 2 ) extending inner lever ( 4 ), the outer lever ( 3 ) in its end region ( 5 ) from a transverse axis ( 6 ) is penetrated on the relatively pivotable to the outer lever ( 3 ) the inner lever ( 4 ) with his thighs ( 7 ), the levers ( 3 . 4 ) are coupled together via coupling means so that when coupling a large and decoupling a smaller or no valve lift is transmitted and wherein the transverse axis ( 6 ) of at least one torsion spring ( 13 ) is embossed as a lost-motion spring whose one end ( 14 ) against a stop ( 15 ) of the outer lever ( 3 ) and its other end ( 16 ) against a stop ( 17 ) of the inner lever ( 4 ), and applying the one end ( 14 ) on the transverse axis ( 6 ) and with the levers ( 3 . 4 ) preassembled torsion leg spring ( 13 ) against the attack ( 15 ) of the outer lever ( 3 ) in an untensioned state, characterized in that the other end ( 16 ) the torsion leg spring ( 13 ) via a first force vector (F1) acting there and via guide means ( 21 ) against the attack ( 17 ) on the inner lever ( 4 ) is stretched. Method according to claim 7, characterized in that the one end ( 14 ) the torsion leg spring ( 13 ) in an untensioned state against an inner surface ( 24 ) of a plant ( 10 ) for the gas exchange valve as a stop ( 15 ) on the outer lever ( 3 ) is created. A method according to claim 7, characterized in that for clamping a first force vector (F1) at the other end ( 16 ) the torsion leg spring ( 13 ) perpendicular to the transverse axis ( 6 ) inwards towards the bottom ( 8th ) of the rocker arm ( 1 ) attacks. A method according to claim 7 or 9 characterized characterized in that for clamping the other end ( 16 ) the torsion leg spring ( 13 ) over a draft ( 21 ) on one of the insides ( 20 ) of the thighs ( 7 ) of the inner lever ( 4 ) is guided and bent and at a contact surface ( 23 ) comes to the concern. Method according to claim 7, characterized in that the other end ( 16 ) the torsion leg spring ( 13 ) against both the contact surface ( 23 ) of the draft ( 21 ) as well as against the inside ( 20 ) of the thigh ( 7 ) of the inner lever ( 4 ) is stretched. A method according to claim 7, characterized in that for clamping a further second force vector (F2) at the other end ( 16 ) the torsion leg spring ( 13 ) attacks. A method according to claim 7 or 12, characterized in that for clamping the second force vector (F2) at the other end ( 16 ) the torsion leg spring ( 13 ) parallel to the transverse axis ( 6 ) attacks inside. Method according to one of claims 7 to 13, characterized that all Procedural steps can be automated. Method according to one of claims 7 to 13, characterized in that exactly two torsion springs ( 13 ) on the transverse axis ( 6 ) whose other ends ( 16 ) related to this transverse axis ( 6 ) are axially outside.