DE20320299U1 - Laser structuring of metal surfaces is used to achieve a specific surface roughness and is used in engine components - Google Patents

Abstract

An item such as a connecting rod used in an engine has bearing shells (18) clamped between the main rod (2) and a cap (6) secured by screws (12). To prevent slippage the surface of the cap and rod contact surface (20,22) is roughened using a laser. The surface pattern produced can be raised cross hatching, parallel lines or a matrix of dots. This provides an average roughness of Ra equal to 0.8 and 2.5.

Description

The invention relates to a component according to claim 1 and an apparatus for processing such Component according to claim 7.

The purpose of such structures is a frictional Connection between the warehouse and one in this warehouse produce recorded bearing shell, so that a relative movement during operation between the bearing holder and the bearing shell and thus an eating of Bearing shell in the bearing seat is prevented.

Known solutions provide the inner peripheral surface of the Machining the bearing bore mechanically by honing. A honing stone is introduced into the bearing receptacle and preferably in this in a translationally and rotationally superimposed movement along the inner peripheral surface guided. This results in a cross section, due to its diagonal and intersecting depressions a slipping of the bearing shell counteract.

The disadvantage of these solutions is that the honing stone is subject to mechanical wear, so that the Indentations created during honing have irregular geometries and therefore no optimal friction between the bearing shell and the bearing seat can be reached.

Another disadvantage is that that too machining workpiece in the known mechanical processes with an additional Force is applied, the unfavorable Can cause stress in the finished component.

A further disadvantage is that with the Honing only a very limited number of different structures is feasible so that on individual requirements can usually not be responded to.

Object of the present invention is to a component and a device for its processing create in which the aforementioned disadvantages are eliminated and a consistently high quality of contact surfaces allows is.

This task is solved by a component with the features of claim 1 and by a Device with the features according to claim 7.

The invention provides for education of surface structures in the form of preferably line-like depressions in contact surfaces of two force fit connected body, bring the wells into the contact surface to be treated using a laser beam. The Wells may be formed in sections or over the entire investment area extend.

The one body or the one workpiece a connecting rod or a universal joint fork and the contact surface to be treated Inner circumferential surface a warehouse inventory. The second body is accordingly one Bearing shell, which is included in the bearing holder. Through the lasered structure, the inner peripheral surface is roughened, so that this in the joined State compared to the adjacent outer peripheral surface of the Bearing shell has a braking effect and therefore no relative movement between the bearing holder and the bearing shell of the bearing shell.

There is an advantage of the solution according to the invention in that by the structures of reproducible quality can be produced by lasering, so that at a Mass production of the body to be processed or workpiece a consistently high quality and thus e.g. in the case of connecting rods, high guidance accuracy on one Crankshaft can be reached.

They are also about one appropriate control of the laser practically any geometry producible, e.g. a cross structure, a parallel structure or a dot matrix. Preferably, the cross structure have the Parallel structure and the dot matrix ejections so that in the Cross section of a sawtooth Structure results. The structure is preferably chosen so that the Joining yourself, i.e. the structure when inserting the bearing shell into the bearing seat does not have a negative effect, i.e. there is no ticking of the touching contact surfaces or moving the bearing shell used.

Another advantage is that the Laser beam is not subject to wear and thus maintenance intervals are significantly extended. Furthermore Most of the particles released from the contact surface by the laser beam evaporate so that to one creates less dirt and the other on structuring the contact surface downstream work step for cleaning the treated contact surface can be omitted.

The contact surface is preferably in front of the Structuring with a defined cutting edge turned so fine that a center roughness value Ra = 0.8 µm up to 2.5μm and an average roughness depth Rz = 5μm to 20μm is achieved.

The laser is outside of the invention Stock picking arranged. The laser beam can pass through a centrally above swivel mirror device positioned in the bearing seat with a swivel mirror on the inner circumferential surface be redirected. By turning and tilting the Swiveling mirror, the entire inner circumferential surface is the same accessible in a rotationally symmetrical manner.

The connecting rod is mainly on one Support table clamped with a suction channel. The suction channel ends in a suction device so that when the pattern is introduced evaporated particles are sucked off or blown off immediately.

To health and safety regulations such as laser protection class 1 , enough and in order not to negatively influence the laser beam due to environmental influences, a protective hood is at least around the La geraufnahme the clamped workpiece placed, which rests on the support device and the swivel mirror device, so that a separate interior from the environment is created.

The device according to the invention sees one Laser for generating a laser beam, a swivel mirror device with a 3D swivel mirror to deflect the laser beam onto one to be machined of a body or workpiece, in particular an inner peripheral surface a bearing of a connecting rod or a universal joint fork, one Support device for clamping the workpiece, preferably with a Suction channel to remove dirt, and a protective hood to create a separate working space for the connecting rod in front.

Because of the low required Performance to bring the structures are simple, on the market available Marking laser, preferably Nd: YAG laser can be used.

Alternatively, to create the Work area either the protective hood can be lowered or the support device be designed with a lifting device.

In a preferred embodiment the support device is designed as a rotatable rotary table its outer circumference at least one swivel mirror device is provided.

In another preferred embodiment is at least one swivel mirror device on a turntable on the Rotary table stored.

Other advantageous embodiments are Subject of further subclaims.

The following is a detailed one explanation preferred embodiments the invention based on schematic representations. Show it

1 2 shows a perspective partial view of a connecting rod with a bearing seat and a bearing shell received in the bearing seat,

2 3 shows a plan view of a first exemplary surface structure,

3 a plan view of a second surface structure,

4 a plan view of a third surface structure,

5 a cross section through 4 .

6 2 shows a front view of a preferred device for surface structuring,

7 3 shows a top view of a connecting rod with recess structures in sections,

8th a plan view of a first arrangement of the device 6 .

9 a plan view of a second arrangement of the device 6 .

10 a plan view of a third arrangement of the device 6 ,

1 shows a view of a large eye 2 of a finished connecting rod 4 , The big eye 2 is a two-part bearing with a bearing cap 6 and a warehouse floor 8th trained to form a warehouse inventory 10 via screws (not shown} in bores 12 are joined together. In the warehouse 10 is a bearing shell 14 with two semi-circular bearing shell arches 16 . 18 added. The outer diameter d1 corresponds to the bearing shell 14 approximately the inside diameter d2 of the bearing holder 10 so that by joining the big eye 2 by means of the screws a frictional connection between the inner peripheral surface 20 the inventory 10 and the area around the aun 22 the bearing shell 14 results. According to the invention, at least the inner peripheral surface is used to reinforce the frictional engagement 20 the inventory 10 provided with a roughening structure. Possible structures for strengthening the frictional engagement are exemplified in the 2 . 3 and 4 shown.

In the 2 surface structure shown is a cross structure 24 , in the 3 shown a parallel structure 26 and the in 4 surface structure shown a dot matrix 62 , The sample 24 . 26 . 62 consist of a variety of in the inner peripheral surface 20 wells made with a laser beam 28 together.

Preferably the cross structure 24 and / or the parallel structure 26 formed with ejections (not shown) as a line-like sawtooth structure, so that the coefficient of friction and the adhesion of the bearing shell 14 in the warehouse 10 is further improved. Ejection is understood to mean a material comb made of melted material, which is located at least on one side next to and in sections along the recess 28 on the inner circumferential surface 20 formed.

The dot matrix 62 has a plurality of craters spaced apart and arranged in lines 64 on. The craters 64 can, however, be arranged with respect to one another. For example, a star-like or freely chosen relative arrangement is also the crater 4 conceivable to each other. The craters 64 are punctually in the inner circumferential surface 20 introduced and have a ring-like ejection 66 made of melted material to increase the coefficient of friction ( 5 ). Particularly advantageous on the dot matrix 62 is that the beam time for introducing the wells 28 and the effects of heat on the inner peripheral surface 20 compared to the cross or parallel structure 24 . 26 is significantly reduced.

Basically, any pattern 24 . 26 . 62 or recess structures that can be combined and implemented with the laser, not only in their flat course, but also in their geometry such as depth and width of the recesses 28 differ.

To reduce the heat input into the inner circumferential surface 20 and to increase the cycle time, it is conceivable to use the recesses 28 only in sections, for example on two or four diametrical ones Inner circumferential sections 76 . 78 . 80 . 82 , ( 7 ) to bring. Furthermore, it is conceivable to steer the laser beam in such a way that wave-like depressions (not shown) are formed, as a result of which compared to straight-line depressions 28 created a much larger effective area and thus a much greater braking effect of the two contacting surfaces 20 . 22 can be achieved via the frictional connection.

All patterns 24 . 26 . 62 are ideally designed such that there is an effective frictional connection between the joined bodies in the assembled state 4 . 14 sets, but when assembling the body 4 . 14 no hooking of the spaced contact surfaces 20 . 22 occurs. This enables simple assembly, and at the same time prevents the formed depressions from being removed during insertion and the desired frictional engagement being adversely affected.

The inner circumferential surface is preferably 20 before making the wells 28 finely turned with a defined cutting edge in such a way that it has an average roughness value Ra = 0.8 μm to 2.5 μm and an average roughness depth Rz = 5 μm to 20 μm.

6 shows a preferred device 30 for inserting the wells 28 in an investment area. In the embodiment described here, the depressions 28 in inner peripheral surfaces 20 a connecting rod 4 brought in. The device 30 essentially has a support device in the illustrated embodiment 32 and a swivel mirror device 34 ,

The support device 32 acts as a connecting rod holder and is preferably a rotary table ( 8th . 9 . 10 ) and / or as a lifting table for variable height adjustment.

To remove dirt from the machined inner circumferential surface 20 has the support device 32 preferably a suction channel 36 that is from the top 38 the support device 32 to the bottom 40 extends and opens into a suction device (not shown).

The connecting rod 4 is so on the support device 32 positioned it with its inventory 10 the suction channel 36 encloses on the top. The inner diameter of the suction channel d3 corresponds approximately to the inner diameter d1 of the bearing holder 10 ,

Due to the advantageous arrangement of the connecting rod 4 in relation to the suction channel 36 can when inserting the wells 28 through a laser beam 42 particles that have not evaporated can be removed effectively and easily. In addition, vapors that have developed are removed by the suction device.

The swivel mirror device 34 serves to deflect the laser beam emitted by a laser (not shown) 42 towards the inner peripheral surface 20 the inventory 10 ,

The swivel mirror device 34 is above the warehouse 10 positioned and has a 3D swivel mirror 44 on. The 3D swivel mirror 44 can execute a 360 ° circumferential movement around a rotation axis R, as well as a tilting movement about a tilt axis K, which runs orthogonally to the rotation axis and is carried along according to a rotation of the 3D swivel mirror about the rotation axis R. The 3D swivel mirror is preferred 44 positioned with its axis of rotation R aligned with the bearing receiving axis L and can be aligned with the connecting rod using appropriate software 4 Getting corrected. With a 360 ° rotation and a corresponding tilting of the 3D swivel mirror 44 can the laser beam 42 any position on the inner circumferential surface 20 control so that the inventory 10 can be machined in the axial and circumferential directions.

In addition to the rotating and tilting movement of the 3D swivel mirror 44 is this or the swivel mirror device 32 preferably vertically and horizontally displaceable and correctable via software in its vertical and horizontal orientation, so that, for example, indentations 28 in the vertical direction not only via a tilting movement of the 3D swivel mirror, but also via a vertical displacement of the swivel mirror device 32 can be formed, due to the constant distance of the 3D swivel mirror 44 to the inner peripheral surface 20 Laser parameters to achieve similar depressions 28 do not need to be changed.

To health and safety regulations, especially laser protection class 1 to suffice and around the laser beam 42 A protective hood is not to be negatively influenced by environmental influences 46 provided between the swivel mirror device 34 and the support device 32 one from the outside 48 completed interior 50 forms in which the connecting rod 4 at least with his inventory 10 is included. The protective hood is preferred 46 on the swivel mirror device 34 attached and is by a vertical lowering movement of the swivel mirror device 34 around the inventory 10 placed until she with her sealing lip 60 on the support device 32 is applied.

In a method according to the invention for surface structuring, in particular for introducing line-like depressions 28 in the inner peripheral surface 20 a warehouse inventory 10 a connecting rod, becomes the inner circumferential surface 20 finished in such a way, for example by fine turning, that it has a mean roughness value Ra = 0.8 μm to 2.5 μm and an average roughness depth of Rz = 5 μm to 20 μm. Then the connecting rod 4 with his inventory 10 according to the above statements with reference to the suction channel 36 and the 3D swivel mirror on the support device 32 clamped, and the protective hood 46 to form an interior or work space 50 lowered. The laser parameters are set and the 3D Sweep mirror 44 controlled so that the desired structure in the inner peripheral surface 20 looming. In parallel to the laser process, the suction device sucks dirt from the interior 50 or from the inner peripheral surface 20 , After the surface structuring is finished, the protective hood lifts 46 and the connecting rod 4 is transported clocked.

The 8th and 9 show arrangements of the swivel mirror devices 34 on the outer circumference 68 a support device designed as a rotatable rotary table 32 for synchronous processing of inner peripheral surfaces 20 of inventory 10 several connecting rods 4 , The feeding and removal of the connecting rods 4 takes place via an angle arm 70 ,

Such arrangements are particularly advantageous for increasing the output. Furthermore, the arrangements according to the 8th and 9 advantageous that either a rotation of a mirror 44 of the swivel mirror devices 34 around its axis of rotation R can be omitted, since this rotation is caused by a section or stepwise rotation of the rotary table 32 can be taken over.

The number of pivoting mirror devices preferably corresponds to at least half the number of those in the contact surfaces 20 deepening structures to be introduced. In the case of an odd number of recess structures, such as three or five, the number of swivel mirror devices can be chosen freely.

According to 8th are at the rotary table 32 two swivel mirror devices 34 intended. The angular distance of the swivel mirror devices 34 from the angle arm 70 and to avoid idling, each other is selected so that when the rotary table rotates 32 always a connecting rod 4 the next station 34 . 70 is fed. With an angle arm 70 and two swivel mirror devices 34 the angular distance is therefore 120 °. In every swivel mirror device 34 can be a side facing her 72 . 74 the inner peripheral surface 20 the inventory 10 the connecting rod 4 are processed so that by passing through both swivel mirror devices 34 their entire inner peripheral surface 20 can be frayed.

The round table 32 is with connecting rods 4 equipped, whereby by the rotation of the rotary table 32 the connecting rods 4 successively the swivel mirror devices 34 fed and processed there in sections. The cycle time for feeding and removing a connecting rod 4 corresponds approximately to the machining time of a connecting rod 4 in a swivel mirror device 34 , Overall, the round table 32 with three connecting rods 4 equipped, two of the swivel mirror devices 34 for lasering and one for the angle arm 70 is assigned for feeding or discharging.

According to 9 it is also conceivable at the rotary table 32 four swivel mirror devices 34 to be provided to avoid idle timing with the angle arm 70 are arranged at an angle of 80 ° to each other. So the rotary table 32 with five connecting rods 4 be equipped, four of which are the swivel mirror devices 34 and one the angle arm 70 assigned.

The relative orientation of the swivel mirror devices 34 to each other is chosen so that each has an inner peripheral portion 76 . 78 . 80 . 82 the side 72, 74 facing her can access, so that after going through all the pivoting mirror devices 34 the inner peripheral surface 20 in sections or completely with recesses 28 is provided.

10 shows a further preferred arrangement of a swivel mirror device 34 for making recesses 28 in an inner peripheral surface 20 a warehouse inventory 10 one on a round table 32 open connecting rods 4 , In this embodiment, the swivel mirror device 34 diametrical to the angle arm 70 over a turntable 84 on the outer circumference 68 of the rotary table 32 arranged so that the swivel mirror device 34 their relative position to the connecting rod 4 by rotating the turntable 84 can change. Thus, the swivel mirror device 34 the entire inner circumferential surface over a 360 ° rotation 20 the inventory 10 of the connecting rod 4 processed.

One method and one is disclosed Surface structuring device of contact surfaces two frictionally interconnected bodies using a laser.

2

big eye

4

pleuel

6

bearing cap

8th_

bearing housing

10

bearing seat

12

drilling

14

bearing shell

16

Bearing shell bow

18

Bearing shell bow

20

Inner circumferential surface

22

Outer circumferential surface

24

cross structure

26

parallel structure

28

deepening

30

contraption

32

support device

34

Swivel mirror device

36

suction

38

top

40

bottom

42

laser beam

44

swivel mirror

46

guard

48

external environment

50

inner space

60

sealing lip

62

dot matrix

64

crater

66

ejection

68

outer periphery

70

angle arm

72

page

74

page

76

Inner peripheral portion

78

Inner peripheral portion

80

Inner peripheral portion

82

Inner peripheral portion

84

turntable

Claims (12)

Component, especially connecting rod or universal joint fork, with a bearing mount ( 10 ) into which a bearing shell ( 14 ) is used, with inventory ( 10 ) and bearing shell ( 14 ) along a contact surface ( 20 ) rest against each other in the recesses ( 28 ) are introduced, characterized in that the depressions ( 28 ) are introduced by radiation treatment using a laser. Component according to claim 1, wherein the bearing holder ( 10 ) before inserting the wells ( 28 ) finished, preferably finely turned with a mean roughness Ra = 0.8μm to 2.5μm and an average roughness depth of Rz = 5μm to 20μm. Component according to claim 1 or 2, wherein the depressions ( 28 ) a parallel structure ( 24 ) form. Component according to claim 1 or 2, wherein the depressions ( 28 ) a cross structure ( 26 ) form. Component according to claim 1 or 2, wherein the depressions ( 28 ) a dot matrix ( 62 ) form. Component according to one of the claims 3 . 4 or 5 , where the structures ( 24 . 26 ) or the dot matrix ( 28 ) Expectorations ( 66 ) have, so that sawtooth-like structures result. Device for processing a component according to one of the preceding claims, with - a laser for generating a laser beam ( 42 ), - a swivel mirror device ( 32 ) with a swivel mirror ( 44 ) to deflect the laser beam ( 42 ) on a contact surface of a body to be machined, in particular the inner peripheral surface ( 20 ) a warehouse ( 10 ) a connecting rod ( 4 ) or a universal joint fork, - a support device ( 32 ) for clamping the body, preferably with a suction channel ( 36 ) to remove dirt, - a protective hood ( 46 ) to create one from the outside environment ( 48 ) separate interior ( 50 ) in which the body, at least with its bearing ( 10 ) is arranged and - a control for actuating the swiveling mirror device on that in the contact surface ( 20 ) Wells can be introduced. The device of claim 7, wherein the laser is a Marking laser, preferably an Nd: YAG laser. Apparatus according to claim 7 or 8, wherein the protective hood ( 46 ) on the swivel mirror device ( 34 ) is arranged and via this on the support device ( 32 ) can be lowered. Apparatus according to claim 7, 8 or 9, wherein the support device ( 32 ) is designed as a lifting table. Device according to one of claims 7 to 10, wherein the support device ( 32 ) is designed as a rotary table and at least one swivel mirror device ( 34 ) on the side outside of the rotary table ( 32 ) is stored. Apparatus according to claim 11, wherein at least one swivel mirror device ( 34 ) via a rotary table ( 84 ) is stored.