DE102011079605A1 - Drag lever for the valve train of an internal combustion engine - Google Patents

Abstract

In a drag lever for the valve train of an internal combustion engine, which is produced as a sheet metal part and two side walls (22, 23) with aligned recesses (28), in which a bearing pin (25) for a surrounding rotatable roller (24) used with its end regions is, wherein the roller (24) is provided for the rolling contact of the cam of a camshaft, according to the invention each have a side wall (22, 23) of the finger lever (21) in the axial direction of the bolt (25) outwardly deformed contact region (29, 30 ) for an end face of the bolt (25). As a result, bolt migration out of the drag lever (21) is prevented in a structurally simple manner.

Description

Field of the invention

The invention relates to a drag lever for the valve gear of an internal combustion engine, which is produced as a sheet metal part and has two side walls with aligned recesses in which a bearing pin is used for a surrounding this rotatable roller with its end regions, wherein the role for the rollable plant a Exzenters or a cam is provided.

Background of the invention

A valve train with a cam follower of the type mentioned is from the document DE 42 34 868 A1 known. The drag lever has there as recesses, in which the end portions of the bearing pin are used, a bore in each side wall. About the type of attachment of the bolt in the holes of the side walls of the finger lever this publication details are not removable. In known rocker arms for valve trains with holes for receiving the end portions of a bearing pin for forming the bolt on the side walls of the rocker arm is a forming process, for. B. caulking or riveting the bolt required, or it will require an additional fuse element.

By applying a forming process to the bolt, however, the choice of its material is limited. In addition, an elaborate caulking or riveting machine is required for the forming, through the function of the entire cycle time of the manufacturing process is extended. Design solutions with additional securing elements for fixing the bolt in the respective bore of the side wall have the disadvantage that they require additional components and often require a groove profiling of the bolt.

Summary of the invention

The invention has for its object to provide a drag lever with a bearing pin arranged therein, in which neither a forming process for the bolt nor an additional security component is required.

This object is achieved in that in each case one side wall of the finger lever has an outwardly deformed in the axial direction of the bolt abutment region for an end face of the bolt.

The abutment area for the bolt may extend on the side wall from its upper edge. The upper edge of the side wall is adjacent the contact point on the circumference of the roller on which the cam acts on the roller. The bolt may abut with its upper end face on the plant area of the side wall. As a result, the axial mobility of the bolt is limited and also kept the rigidity of the finger lever with the inserted bolt constant or even increased depending on the space.

The outwardly deformed contact region of the side wall may be formed U-profile-shaped. The recess of the side wall has a circular cylindrical, upwardly open contour whose circumferential angle is either greater than 180 degrees, wherein the circular cylindrical bolt is then firmly snapped with its end into the recess.

Or the circumferential angle of the contour of the recess is equal to or less than 180 degrees, then the bolt is loosely inserted with its end portion in the recess, so not fixed therein. In both cases, however, the bolt is held radially positively in the recess.

The achievable with the rocker arm according to the invention consist in a free choice of material for the bolt, a simplified assembly process, the form fit against a bolt migration in the axial direction and possibly an increased rigidity over known rocker arms.

Short description of the drawing

An embodiment of the invention is illustrated in the drawing and will be described in more detail below in comparison with a finger follower according to the prior art. Show it

1 a drag lever according to the invention in a perspective view;

2 the drag lever in a side view;

3 the drag lever in a vertical longitudinal section;

4 the drag lever in a vertical cross-section;

5 the rocker arm in a bottom view, partly with a section in the storage area;

6 a previously known valve train with a drag lever in longitudinal section.

Detailed description of the drawing

The previously known valve train 1 a reciprocating internal combustion engine according to 6 The drawing is in a partially illustrated cylinder head 2 arranged and consists of the cam 3 a camshaft, not shown, a drag lever 4 with a roll 5 , a support element 6 and a gas exchange valve 7 , The support element 6 is in a receiving hole 8th of the cylinder head 2 arranged and is via a pressure fluid hole 9 supplied with oil. Furthermore, the support element has a spherical end section 10 on which a spherical cap 11 of the rocker arm 4 is supported.

The rocker arm 4 can be made as a sheet metal part, wherein it has a substantially U-shaped cross-section. At his from the spherical calotte 11 opposite end 12 engages the rocker arm 4 on a valve stem 13 of the gas exchange valve 7 at. The gas exchange valve 7 has a valve plate 14 up and over a valve spring 15 that has a spring plate 16 at the valve stem 13 is fixed in the axial direction, biased in the closed position. The role 5 is about a bolt 17 in side walls 18 . 19 of the rocker arm 4 guided. For rotatable storage of the roll 5 on the bolt 17 , which is fixed in the side walls, serves a needle bearing 20 , Upon rotation of the cam 3 the role rolls 5 on the circumference of the cam 3 from.

The drag lever according to the invention 21 has two interconnected parallel side walls 22 and 23 on, in the space between them a role 24 on a bearing bolt 25 is rotatably mounted. For storage, a rolling bearing or a plain bearing is possible. In the exemplary embodiment is a needle bearing 26 provided, whose arrangement in the 3 to 5 the drawing is shown. The needle bearing 26 surrounds the bearing pin 25 and is off the roll 24 surrounded concentrically. About its two axial end portions of the bolt 25 in the side walls 22 and 23 of the rocker arm 21 held. Each end of the bolt 25 is in a recess 27 respectively. 28 used the respective side wall.

As 2 shows, has the recess 28 the side wall 23 a circular cylindrical, upwardly open contour with a circumferential angle a. Likewise, the recess 27 the side wall 22 educated. According to the amount of this peripheral angle is the bolt 25 with its two end portions in the recesses 27 and 28 either firmly snapped or loosely inserted, leaving it there in the side walls 22 and 23 is held radially positively.

For limiting the movement of the bolt 25 in the axial direction, each side wall 22 respectively. 23 an outwardly deformed investment area 29 respectively. 30 on. These investment areas extend in the upper part of the bolt 25 from the upper edges of the side walls 22 and 23 off and end above the circular cylindrical contours of the recesses 27 and 28 , Because the two front sides of the bolt 25 the inner surfaces of the investment areas 29 respectively. 30 the side walls 22 respectively. 23 adjacent, the axial mobility of the bolt is limited by the contact areas.

LIST OF REFERENCE NUMBERS

1

 valve train

2

 cylinder head

3

 cam

4

 cam follower

5

 role

6

 support element

7

 Gas exchange valve

8th

 location hole

9

 Pressure medium bore

10

 end

11

 spherical cap

12

 The End

13

 valve stem

14

 valve disc

15

 valve spring

16

 spring plate

17

 bolt

18

 Side wall

19

 Side wall

20

 needle roller bearings

21

 cam follower

22

 Side wall

23

 Side wall

24

 role

25

 bearing bolt

26

 needle roller bearings

27

 recess

28

 recess

29

 plant area

30

 plant area

a

circumferential angle

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 4234868 A1 [0002]

Claims (6)

Rocker arm for the valve train of an internal combustion engine, which is produced as a sheet metal part and two side walls ( 22 . 23 ) with aligned recesses ( 27 . 28 ), in which a bearing pin ( 25 ) for a surrounding rotatable roller ( 24 ) is used with its end portions, wherein the roll ( 24 ) is provided for the rolling contact of an eccentric or a cam, characterized in that in each case a side wall ( 22 . 23 ) of the rocker arm ( 21 ) one in the axial direction of the bolt ( 25 ) outwardly deformed investment area ( 29 . 30 ) for a front side of the bolt ( 25 ) having. Drag lever according to claim 1, characterized in that the recess ( 27 . 28 ) of the side wall ( 22 . 23 ) has a circular cylindrical, upwardly open contour. Drag lever according to claim 2, characterized in that the circumferential angle (a) of the contour of the recess ( 27 . 28 ) is greater than 180 degrees, with the bolt ( 25 ) with its end portion in the recess ( 27 . 28 ) is snapped firmly. Cam follower according to claim 2, characterized in that the circumferential angle of the contour of the recess is equal to or less than 180 degrees, wherein the bolt ( 25 ) is loosely inserted with its end in the recess. Drag lever according to claim 1, characterized in that the contact area ( 29 . 30 ) for the bolt ( 25 ) on the side wall ( 22 . 23 ) is formed starting from the upper edge, which of the contact point of the roll ( 24 ) is adjacent to the cam. Drag lever according to claim 1, characterized in that the outwardly deformed contact area ( 29 . 30 ) Is U-shaped profile.

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