WO2010094324A1

WO2010094324A1 - Method and device for introducing surface structures, in particular surface roughnesses, into the contact surface of a component

Info

Publication number: WO2010094324A1
Application number: PCT/EP2009/051906
Authority: WO
Inventors: Horst Wisniewski
Original assignee: Alfing Kessler Sondermaschinen Gmbh
Priority date: 2009-02-18
Filing date: 2009-02-18
Publication date: 2010-08-26

Abstract

The invention relates to a method for introducing surface structures, in particular surface roughnesses (70), in the contact surface (20) of a component (2), in particular a connecting rod or a universal joint yoke, having a friction fit with a further part (26), in particular a bearing shell, wherein the surface structures are introduced into the contact surface of the component for increasing the friction, wherein the contact surface is impinged at least in segments by a shot carrying an impulse for producing the surface structures.

Description

Method and device for introducing

Surface structures, in particular surface roughness, in the contact surface of a component

Technical area

The present application relates to a method and a device for introducing surface structures, in particular surface roughnesses, in a contact surface of a component, in particular a connecting rod or a universal joint fork, which is frictionally connected to a further part, in particular a bearing shell.

Background of the invention

In the eyes of connecting rods or in the corresponding holes of universal joint forks for the purpose of friction reduction and to prevent seizure bearing shells are inserted, the running side is typically made of Bundmetalllegierungen, and the back of a firmer substrate, preferably steel.

These bearings must be secured against axial displacement and the other against rotation to ensure their proper functioning.

In some known embodiments, the bearing shells are secured in the respective eye by retaining lugs on the circumference of the bearing shells, which engage in corresponding grooves in the eye, against axial displacement. For this purpose, wedge-shaped retaining lugs are typically used in conjunction with corresponding wedge-shaped grooves, which are attached for example to the bearing shells and on the cover side and the shaft side of the respective connecting rod. These wedge-shaped lugs and grooves are very well suited as a safeguard against axial displacement of the bearing shells. As rotation, however, they are not optimal, since any rotation of the bearings due to the resulting wedge effect can lead to a reduction in diameter of the bearing shells, which in turn can increase the friction on the crankshaft or the universal joint axis and thus ultimately for clamping or seizing the connecting rod or the Can lead to universal joints.

Accordingly, the roughness of the bearing eyes is specifically increased, so that the carrier material of the bearing shells can frictionally connect with the roughness and / or dig into the roughness, so that a rotation of the bearing shells is achieved.

Since the requirements for the quality of the holes or eyes in the connecting rod are very high, usually dimensional accuracies of 0.008 mm of the cylindrical shape are required, the connecting rod bore is typically honed after fine boring. The resulting honing structure is applied by a honing stone, which moves translationally and rotationally in the connecting rod bore, so that there is a cross-grinding, which increases the friction between the bearing shells and the connecting rod eye due to its diagonal and intersecting recesses to improve the security against rotation. However, these honing structures can typically not be designed as structures raised in relation to the abutment surface, so that a limit is placed on the production of high coefficients of friction.

DE 103 25 910 A1 discloses a further method for surface structuring of the corresponding contact surfaces, for example in a connecting rod eye or the eye of a universal joint fork, recesses being introduced into the contact surface to be treated by machining by means of a laser beam. The use of the laser and the associated temperature input into the connecting rod or the universal joint fork can lead to a structural change of the material and in particular to a martensite formation, which can influence the structural integrity of the component.

description

Starting from the known methods for

Surface structuring, it is the object of the present invention to propose an alternative method which greatly reduces the disadvantages described above.

Another object of the present method is to further reduce or prevent both an axial displacement and a rotation of the bearing shell relative to the connecting rod eye or the bearing shell relative to the bearing bore of the universal joint fork.

Such a method for introducing surface structures is proposed in claim 1. In particular, the surface roughness in the contact surface of a component, in particular a connecting rod or a universal joint fork, which is frictionally connected to a further part, in particular a bearing shell to increase the friction on the bearing surface of the component introduced. These surface structures are produced according to claim 1 by applying the contact surface at least in sections to a blasting material carrying an impulse.

The impingement of the contact surface with an abrasive material carrying an impulse causes roughness peaks in the abutment surface to be thrown up by the blasting material. These roughness peaks represent a surface structure in the contact surface of the component and thus increase their Surface roughness, in particular for increasing the friction on the Aniageflache.

The application of the contact surface with the blasting material corresponds at first sight substantially to the fundamental principle of sandblasting the contact surface. When sandblasting, however, typically only a removal of Oberf surface coatings or

Surface contamination or a smoothing of the surface tracked within certain parameters.

In the present method, however, the parameters of the application, in particular the momentum of the blasting material and its angle of incidence, adjusted so that a targeted surface structure is introduced into the contact surface and introduced in particular elevations, which occur beyond the plane of the contact surface, in the contact surface. This can be achieved, in particular, by the parameters energy, that is to say, in particular, the fluid pressure and fluid velocity, the type of blasting material, and the quantity of blasting material being correspondingly coordinated with one another. In particular, the impulse is applied substantially perpendicularly, or at least at a staggered angle, to the contact surface, so that the corresponding surface structures and elevations arise.

In a preferred variant of the method, the pulse is applied to the blasting material by means of a fluid, in particular by means of compressed air, and applied to the contact surface with a blasting material fluid mixture. The pulse can also be applied mechanically to the blasting material, for example by mechanical ejection of the blasting material.

In a preferred embodiment, the application of the contact surface with the blasting material takes place only in surface sections of the contact surface. In particular, can the blasting material in surface points or surface spots are applied to the contact surface, so that in particular a matrix of surface structures is produced on the contact surface. The term "area point" is not understood here to mean applying in the sense of a mathematically defined point, but rather to a point in the sense of an extended spot, which is nevertheless relatively small in relation to the entire contact surface, and which, statistically speaking, is essentially rotationally symmetrical (ie "point-shaped"). ).

Due to the typically statistically distributed impact of the blasting material on the contact surface, a sharply demarcated and unambiguous form of the surface structures produced can not be expected here. Measurements have shown, however, that the application of the contact surface in the region of application of the blasting material forms similar structures at different points of application, and in particular shows a similar density of roughness peaks rising beyond the abutment surface.

In a preferred embodiment of the method, the application of the blasting material takes place in surface sections of the contact surface, in particular in surface points or surface spots, and in particular a matrix of surface structures is produced on the contact surface. By producing a matrix, the friction parameters can be set uniformly over the entire contact surface.

In order to achieve the corresponding effect of the production of the warping and their characteristics, wherein caused by the impingement of the contact surface with the blasting cavities in the form of roughness peaks, in particular the height, the size and the number of Aufwerfungen on the amount of blasting, the Type of Blasting, the particle size of the blasting material, the fluid pressure, the contact time and / or the contact surface set. In this way, the desired parameters and characteristics can be achieved very flexibly.

A preferred embodiment of the method provides that the blasting material-fluid mixture is pulsed applied to the contact surface, or is applied in a single impact of, for example one second on the contact surface.

The loading of the contact surface with the blasting material can advantageously be carried out by means of a nozzle outlet positioned opposite it, the nozzle outlet being pivoted, rotated and / or moved axially in particular relative to the contact surface. As a result, very different patterns of surface structures can be introduced very flexibly and, in addition to the matrix arrangements of the surface structures, also elongate, in particular line-shaped, surface structures can be introduced into the contact surface.

In a further advantageous method step, the contact surface before, during and / or after the application of the blasting material at least partially measured, in particular by means of a mechanical scanner or a laser scanner, wherein the determined surface structures are compared with predetermined surface structure values, and the component based on the determined values either the blasting material is applied once again, the component is transported to the next workstation, or the blasting material is exchanged. In other words, a quality control takes place, on the basis of which it can be determined whether the component is in order and can be forwarded to the next processing station, or whether the surface structuring was insufficient and the component again with the blasting material must be acted upon. Furthermore, it can be determined indirectly in this way, whether the life of the blasting material is exceeded and it must be replaced.

The object is further achieved by a device for introducing surface structures, in particular surface roughness, in the contact surface of a component, in particular a connecting rod or a universal joint fork, which is frictionally connectable with another part, in particular a bearing shell, wherein the surface structures to increase the friction serve on the contact surface of the component. According to claim 7, the device comprises a nozzle outlet positionable with respect to the contact surface to be machined, a jet material reservoir in communication with the nozzle exit, a device for applying a pulse to at least part of the jet material located in the jet material reservoir, and a controller with which the application is applied the contact surface with the blasting material can be controlled.

Preferably, a positioning device for positioning the jet nozzle is provided, by means of which the jet nozzle is pivotable, rotatable or axially movable with respect to the contact surface.

Preferably, the device for applying a pulse to the blasting material on a pressurized fluid, in particular compressed air, for applying the pulse and / or a mechanical device for ejecting the blasting material on.

In a further preferred embodiment, the controller makes it possible to control the amount of blasting material, the momentum, in particular the fluid pressure, the action time and / or the action surface of the blasting material on the abutment surface and, in particular, enables pulsed impingement of the abutment surface with the blasting material. Preferably, at least one nozzle outlet is present in a nozzle body, wherein the nozzle body comprises a blasting material reservoir.

Preferably, the nozzle body is rotatable relative to the contact surface of the component, pivotable and / or axially movable.

In another preferred embodiment, the controller coordinates jet feed, positioning, and fluid delivery.

The object is further achieved in a component, in particular connecting rod or universal joint, wherein the component comprises a contact surface, which is frictionally connected with another part, in particular a bearing shell, wherein to increase the friction between the contact surface of the component and the frictionally This connectable further part at least one surface structure by means of the method described above and / or by means of the device described above is introduced.

Brief description of the drawings

In the following, exemplary devices for introducing surface structures, in particular surface roughness, into a component will be described with reference to the attached drawings.

Showing:

Figure 1 is a schematic cross-sectional view of a structure of a device for introducing surface structures;

Figure 2 is a schematic cross-sectional view through a nozzle body; Figure 3 is a schematic plan view of a with the

Nozzle body according to Figure 2 treated component;

Figure 4 is a schematic cross-sectional view of another device for introducing surface structures in the contact surface of a component;

Figure 5 is a diagrammatic representation of

Surface structures of a contact surface made with a first set of parameters;

Figure 6 is a diagrammatic representation of

Surface structures of a contact surface made with a second set of parameters; and

Figure 7 is a schematic plan view of the big eye of a Bruchpleuels with inserted cups.

Detailed description of the embodiments

In the following, a device for introducing surface structures, in particular of

Surface roughness, shown in the contact surface of a component in several examples. Here, the same reference numerals designate the same or similar elements in the respective figures,

FIG. 1 schematically shows a cross section through a device 1 for introducing surface structures, in particular surface roughnesses, into the contact surface 20 of a component 2. In FIG. 1, a connecting rod 2 is shown as a component, which has a large eye 22 and a small eye 24 , wherein the big eye with the corresponding crankshaft, such as an internal combustion engine or a compressor, whereas the respective piston is connected to the small eye 24.

In the large eye 22 usually not shown in this figure bearing shell is introduced. FIG. 7 shows how the bearing shells 26 are typically introduced into the large eye 22 of the connecting rod 2.

In FIG. 1, a nozzle body 30 is introduced into the large eye 22 of the connecting rod 2, which nozzle nozzle 32 comprises nozzle nozzles 32 which are arranged essentially opposite the contact surface 20 of the connecting rod 2. From the nozzle outlets 32, a blasting material provided with an impulse can emerge and act on the abutment surface 20 of the connecting rod 2.

In the variant shown, a pressurized blasting material / fluid mixture emerges from the nozzle outlets 32, which acts on the contact surface 20 with the impulse applied to the blasting material due to the pressure drop.

The nozzle body 30 is connected to a support structure 34, which comprises a Strahlgutzuführabschnitt 36 and a Fluidzuführabschnitt 38.

The Fluidzuführabschnitt 38 is connected by means of a fluid supply line 40 via a controllable valve 42 with a fluid reservoir 44. In the fluid reservoir, a fluid is provided under pressure, for example compressed air, which can be introduced via the controllable valve 42 and the fluid supply line 40 into the fluid supply section 38 of the support structure 34.

The Strahlgutzuführabschnitt 36 of the support structure 34 is connected via a Strahlgutzuführleitung 50 and a controllable valve 52 with a Strahlgutreservoir 54. The blasting material reservoir 54 in turn is over a Strahlgutrückführung 56 connected to a below the nozzle body 30 arranged Strahlgutsammelbehälter 58.

The ejected from the nozzle exits 32 on the contact surface 20 of the connecting rod 2 Strahlgut falls after energy release or momentum transfer to the contact surface 20, gravitationally in the Strahlgutsammelbehälter 58. From the Strahlgutsammelbehälter 58 it can be promoted on the Strahlgutzufuhr 56 in the Strahlgutreservoir 54, for example by means of a fluid delivery or mechanically by means of a conveyor belt. From the blasting material reservoir 54, the blasting material can be introduced via the valve 52 and the blasting material feed 50 into the blasting material supply section 36 of the holding device 34.

The blasting material 60 itself is present in the embodiment of the device 1 shown in FIG. 1 in the blasting material supply section 36 of the support structure 34 as well as in the bottom region of the nozzle body 30. The nozzle body 30 therefore also serves as a blasting material reservoir. From the jet material supply region 36, the blasting material can be brought into the bottom region of the nozzle body 30 accordingly.

Upon exposure of the nozzle body 30 with a fluid, for example with compressed air, the blasting material 60, which is located at the bottom of the nozzle body 30, swirled up and ejected through the nozzle outlets 32 together with the fluid jet. Accordingly, the contact surface 20 of the connecting rod 2 in the area in front of the nozzle exits 32 with the fluid blasting mixture 62 is acted upon.

By this impingement of the contact surface 20 with the blasting material-fluid mixture, a surface structure in the contact surface 20 of the connecting rod 2 is introduced by the momentum transfer of the blasting material to the contact surface 20. The fluid, for example compressed air, which is introduced from the fluid reservoir 44 via the valve 42 and the fluid supply line 40 into the fluid supply region 38 of the support structure 34, is introduced into the nozzle body 30, for example at a pressure of 8 to 10 bar. Accordingly, the blasting fluid jet, which emerges from the nozzle exits 32 and the contact surface 20 of the connecting rod 2 applied, energetic and the Strahlgutpartikel which impinge on the contact surface 20 of the connecting rod 2, cause protrusions, which remain as roughness peaks in the contact surface.

After the blasting material-fluid mixture has hit 62 on the contact surface 20 and the blasting material has given its energy to the support surface 20, the blasting material falls into the blasting material 58 and can be conveyed back from there into the blasting material 54 by means of Strahlgutfördervorrichtung 56 described above ,

For positioning the individual surface structures on the abutment surface, the blasting material body 30 is preferably movable in the axial direction X and can be positioned within the large connecting rod eye 22 in different axial positions. Preferably, the nozzle body 30 is also rotatable about its longitudinal axis, so that the nozzle exits 32 can be positioned at different locations, both in the axial direction and in the circumferential direction relative to the contact surface 20, so that surface structures can be introduced at different positions of the contact surface 20.

By means of the valve 42, the time during which the fluid flow enters the Düεenkörper 30 can be controlled. Depending on the opening diameter of the nozzle outlets 32, the nature of the blasting material and the pressure of the fluid, so by means of different long exposure times of the Blasting material different surface structures in the contact surface 20 are introduced.

FIG. 2 shows an alternative nozzle body 30 ', which shows nozzle outlets 32' in superimposed configuration. The nozzle outlets 32 'shown here are each provided with inserts 320, which are provided, for example, in the form of ceramic inserts or Harttnetalleinsätzen to reduce increased wear of the nozzle outlets 32' by the Strahlgut "fluid mixture.

This nozzle body 30 'can be introduced into the large eye 22 of the connecting rod 2 in the shape shown in FIG. 1; by arranging the nozzle outlets 32', a faster machining of the respective workpiece can be achieved here.

Of course, the inserts shown in this figure can also be used in the nozzle outlets of the embodiment shown in FIG.

In order to achieve the desired Aufwerfungen in the contact surface is used as blasting a steel gravel, in particular a chill-Strahltnittel. The particle sizes used in each case are, inter alia, the cause of the surface structures arising in the contact surface. If a finer steel gravel is used, for example a chilled cast blasting abrasive having a grain diameter of 0.4 mm, finer surface structures are introduced in the contact surface than when using a coarser steel grit, for example a chilled cast blasting abrasive having a 0.8 mm grain diameter.

Figure 3 shows schematically a contact surface 20 of a component 2 shown as a portion, wherein in the contact surface 20 Aufwerfungen 70 are present, which were generated by the application of the contact surface 20 with a momentum carrying blasting material. It can be seen, inter alia, that the elevations 70 are present in a quasi point-like (or point-cloud-shaped) shape, that is to say in particular not over the entire surface of the contact surface 20, but only in delimited areas. Of course, it would also be possible to introduce elevations 70 uniformly over the contact surface 20 - for this purpose, the nozzle body 30 in FIG. 1 would have to be moved along the contact surface 20 only correspondingly uniformly when the contact surface 20 is subjected to the blasting material-fluid mixture.

Furthermore, it would also be conceivable to provide elevations 70 in the contact surface 20, which are provided substantially annular in the contact surface 20 of the connecting rod 2, for example by rotating the nozzle body 30 about its longitudinal axis during the impact of Anlagefläσhe with blasting.

A punctiform is to be understood here as meaning a structure in which the elevations 70 pile up around a center of gravity, and in particular form an extended spot. In particular, punctiform is here not to be understood as a mathematical point which has no spatial extent.

FIG. 4 shows yet another embodiment of a device for introducing surface structures into a component 2, in particular into a connecting rod 2.

Here, a StrahlgutZuleitung 80 is introduced into the large eye 22 of the connecting rod 2, which is bent at its outlet end 82 so that it directly opposite the contact surface 20. The Strahlgutzuleitung 80 can be positioned anywhere within the large eye 22 and can accordingly apply a blasting fluid mixture on the contact surface 20. In particular, it should be noted here that the embodiments of the device 1 shown in FIGS. 1 and 2 which comprise the nozzle body 30 or 30 'represent only one possible concept.

Rather, it is also conceivable to provide a blasting material fluid stream instead of the blasting material lying on the bottom of the nozzle body 30 in combination with the supply of a pressurized fluid, and then to direct this blasting material fluid flow onto the respective contact surface 20 to be machined.

Here, different embodiments of the respective device to be used are conceivable. It is essential here only that the contact surface for introducing surface structures, and in particular surface roughnesses, is specifically exposed to a blasting material carrying an impulse, in order to introduce the surface structures.

Figure 5 shows diagrammatically the surface structures as a result of mechanical scanning of the abutment surface after machining the abutment surface of a connecting rod with the device shown in Figure 1. The nozzle outlets 32 had a diameter of 3 mm, the pressure applied to the nozzle body 30 was 9 bar, the blasting material had a grain size of 0.8 mm and within a second 50 grams of blasting material were applied to the contact surface of the connecting rod blown by compressed air. As blasting material while a chill-abrasive was used.

The diagram of Figure 5 shows that a significant roughening of the surface has taken place in the region of the impact of the blasting material-fluid mixture.

FIG. 6 shows another diagram, but with different test parameters than in FIG. 5. In FIG Nozzle outlets with a diameter of 5 mm were used, so that at the pressure of 9 bar and a particle size of 0.8 mm of the blasting material, about 70 grams of blasting material were blown onto the contact surface within one second. As blasting material again a chill-blasting abrasive was used.

There is a much broader spread of surface roughening, but less high warps. In the present constellation, this is due to the fact that, due to the larger diameter of the nozzle outlets than in FIG. 5, the jet velocity of the blasting material / fluid mixture, and thus the momentum of the blasting medium impinging on the contact surface, was lower than in FIG. 5.

FIG. 7 once more schematically shows a Crackpleuel, in which the connecting rod 2 has a large eye 22 which is enclosed by the cap of the connecting rod and the shaft end of the connecting rod, and in which bearing shells 26 are introduced.

The measurement of the introduced surface structure, and in particular the introduced surface roughness, can also be used in the performance of the method, inter alia, to find out whether the introduced surface roughness corresponds to a certain standard value. In this way, the structuring carried out with the method can be checked in a simple manner, in particular by means of an easily available laser scanner. On the one hand, process reliability is increased because only components with a given minimum surface roughness leave production. On the other hand, the service life of the blasting material used in each case can be tracked and the time for renewing the blasting material can be determined if the surface roughness achieved within the process is no longer sufficient. It is advantageous, inter alia, that in the method presented here, a structural change and in particular no martensite formation takes place, since the surface, and in particular the contact surface, is not, or at least not significantly, heated.

Claims

claims

1. A method for introducing surface structures, in particular surface roughness (70), in the contact surface (20) of a component (2), in particular a connecting rod or a universal joint fork, which with a further part (26), in particular a bearing shell, frictionally connected , wherein the surface structures are introduced to increase the friction in the contact surface of the component, characterized in that the contact surface for the production of

Surface structures is at least partially acted upon with a momentum carrying a blasting material.

2. The method according to claim 1, wherein the pulse is applied to the blasting material by means of a fluid, in particular compressed air, and the contact surface is subjected to a blasting material - fluid mixture, or the pulse is mechanically applied to the blasting material.

3. The method according to claim 1 or 2, wherein the loading in surface portions of the contact surface, in particular in surface points or surface spots, takes place, and in particular a matrix of surface structures is produced on the contact surface.

4. The method according to any one of the preceding claims, wherein by the application of the contact surface with the blasting cavities are generated in the form of roughness peaks and the characteristics of the surface structure, in particular the height, the size and the number of Aufwerfungen, on the amount of blasting, the Type of grit, the particle size of the grit, the fluid pressure, the exposure time, the contact surface, and the pulse is set.

5. The method according to any one of the preceding claims, wherein the contact surface is acted upon by means of a jet outlet positioned opposite it (32) with the blasting material, and the nozzle outlet in particular pivoted relative to the contact surface, rotated and / or moved axially.

6. The method according to any one of the preceding claims, wherein the contact surface before, at and / or after the application of the blasting material is at least partially measured, in particular by means of a mechanical scanner or a laser scanner, the determined surface structures are compared with predetermined surface structure values, and the component On the basis of the determined values, the blasting material is once again applied to the blasting material, the component is transported to the next workstation, or the blasting material is exchanged.

7. Device (1) for introducing surface structures, in particular surface roughness

(70), in the contact surface (20) of a component (2), in particular a connecting rod or a universal joint fork, which with a further part (26), in particular a bearing shell, frictionally connected, wherein the surface structures to increase the friction in the contact surface of the component, the apparatus comprising: a nozzle outlet (32) which can be positioned opposite the contact surface to be machined, a blasting material reservoir (54) in communication with the nozzle outlet, a device for applying a pulse to at least one part of the latter

Strahlgutreservoirs located blasting, and a controller, with which the application of the

Contact surface can be controlled with the blasting material.

8. Apparatus according to claim 7, wherein a positioning device is provided, by means of which the nozzle outlet is positionable relative to the contact surface.

9. Apparatus according to claim 7 or 8, wherein the device for applying a pulse to the blasting material has a pressurized fluid, in particular compressed air, for applying the pulse and / or a mechanical device for ejecting the blasting material.

10. Device according to one of claims 7 to 9, wherein the controller controls the amount of blasting material, the pulse, in particular the fluid pressure, the contact time and / or the effective surface of the blasting material on the contact surface and in particular a pulsed impingement of the contact surface with the blasting material allows.

11. The device according to one of claims 7 to 10, wherein at least one nozzle outlet (32) in a nozzle body (30) is present, wherein the nozzle body (30) comprises a Strahlgutreservoir.

12. The device according to claim 11, wherein the nozzle body is rotatable relative to the contact surface of the component, pivotable and / or axially movable.

13. The apparatus of claim 12, wherein the controller coordinates jet feed, positioning, and fluid delivery.

14. component, in particular connecting rod or universal joint fork, with a contact surface (20) which is frictionally connectable with a further part (26), in particular a bearing shell, wherein to increase the friction between the contact surface of the component and the frictionally connectable with this further Part at least one surface structure by means of of the method defined in claims 1 to 6 is introduced.

15. component, in particular connecting rod or universal joint fork, with a contact surface (20), which with a further part (26), in particular a bearing shell, frictionally connected, wherein to increase the friction between the contact surface of the component and the frictionally connectable with this further Part at least one surface structure by means of a device according to claims 7 to 13 is introduced.