METHOD FOR MACHINING A BEARING RING AND FOR PRODUCING A ROLLING BEARING

Abstract

A method for machining a bearing ring of a rolling bearing includes providing a blank with an annular surface for producing the bearing ring, clamping the blank in a machine tool, and structuring the annular surface by high-feed milling to form a sealing face. The method may include removing material from the blank to produce a track of the bearing ring while the blank is still clamped in the machine tool, with the blank rotating during the steps of structuring the annular surface and removing material from the blank. The method may also include providing a high-feed milling cutter with a face, and performing the high-feed milling with the face.

Claims

1.-11. (canceled)

12. A method for machining a bearing ring of a rolling bearing, comprising: providing a blank with an annular surface for producing the bearing ring; clamping the blank in a machine tool; and structuring the annular surface by high-feed milling to form a sealing face.

13. The method of claim 12, further comprising removing material from the blank to produce a track of the bearing ring while the blank is still clamped in the machine tool, wherein the blank rotates during the steps of structuring the annular surface and removing material from the blank.

14. The method of claim 12, further comprising: providing a high-feed milling cutter with a face; and performing the high-feed milling with the face.

15. The method of claim 14, further comprising guiding the face in an aligned manner at an angle of 0 to 10° with respect to the annular surface.

16. The method of claim 14, wherein the step of structuring the annular surface by high-feed milling comprises displacing the high-feed milling cutter in an axial direction of the blank during the high-feed milling.

17. The method of claim 16, wherein the high-feed milling cutter describes a helical line or a spiral line on the annular surface during the step of structuring the annular surface by high-feed milling.

18. The method of claim 16, wherein the high-feed milling cutter describes a wavy line that intersects itself multiple times on the annular surface during the step of structuring the annular surface by high-feed milling.

19. The method of claim 14, wherein the step of structuring the annular surface by high-feed milling comprises displacing the high-feed milling cutter in a radial direction of the blank during the high-feed milling.

20. The method of claim 19, wherein the high-feed milling cutter describes a helical line or a spiral line on the annular surface during the step of structuring the annular surface by high-feed milling.

21. The method of claim 19, wherein the high-feed milling cutter describes a wavy line that intersects itself multiple times on the annular surface during the step of structuring the annular surface by high-feed milling.

22. A method for producing a rolling bearing, comprising: providing a first bearing ring produced using the method of claim 12; providing a second bearing ring, a plurality of roller bodies, and a seal; installing the plurality of roller bodies between the first bearing ring and the second bearing ring; and installing the seal on the second bearing ring such that the seal contacts the sealing face of the first bearing ring.

23. A rolling bearing, comprising: a first bearing ring comprising a high-feed milled surface; a second bearing ring; a plurality of roller bodies arranged between the first bearing ring and the second bearing ring; and a seal, held on the second bearing ring and contacting the high-feed milled surface.

24. A wheel bearing comprising the rolling bearing of claim 23.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Below, two exemplary embodiments of the disclosure are explained in more detail through a drawing. In the figures:

[0030] FIG. 1 shows a schematic representation of the machining of a surface of a bearing ring through high-feed milling,

[0031] FIG. 2 shows a perspective view of the bearing ring machined with the method according to FIG. 1,

[0032] FIG. 3 shows a rolling bearing designed as a deep groove ball bearing including the bearing ring according to FIG. 2,

[0033] FIG. 4 shows a section of a rolling bearing designed as a wheel bearing with a bearing ring to be machined according to FIG. 1, and

[0034] FIG. 5 shows different surface structurings formed by means of high-feed milling on surfaces made of a metallic material.

DETAILED DESCRIPTION

[0035] Unless otherwise stated, the following explanations relate to all exemplary embodiments. Parts or structures that correspond to each other or have basically the same effect are marked with the same reference symbols in all figures.

[0036] A rolling bearing identified overall with the reference number 1 is designed as a ball bearing and comprises an inner ring 2 and an outer ring 3 (compare FIG. 3). The rolling bearing 1 shown in FIG. 3 is a deep groove ball bearing, while the rolling bearing 1, only partially sketched in FIG. 4, is a two-row angular ball bearing, namely a wheel bearing for a motor vehicle. In this case, a flange of the inner ring 2 is denoted by 4.

[0037] In both cases, balls roll as roller bodies 5 between the bearing rings 2, 3. The roller bodies 5 can be guided in a cage, not shown. A track 6 of the inner ring 2 contacting the roller bodies 5 and a track 7 of the outer ring 3 contacting the roller bodies 5 can be seen.

[0038] A seal 8, which has a sealing lip 9, is held on the outer ring 3. The sealing lip 9 comes into contact with a surface 10 of the inner ring 2 which, in the case of FIG. 3, describes a concentric cylinder which is parallel to the central axis M of the rolling bearing 1. In the case of FIG. 4, on the other hand, the surface 10 lies on a plane which is oriented to be normal to the central axis M. In both cases, the seal 8 is a contact seal. In a manner not shown, the seal 8 can have more than one sealing lip 9.

[0039] The surface 10, which is contacted by the sealing lip 9, is structured by means of high-feed milling which is illustrated in FIG. 1 and provides a surface structuring 11. This method is used in the production of the inner ring 2 of the rolling bearing 1 according to

[0040] FIG. 3 as well as in the production of the inner ring 2 of the rolling bearing 1 according to FIG. 4, A smooth finishing of the surface 10 provided as a sealing face after the high-feed milling does not take place.

[0041] To produce the inner ring 2, a blank, the basic shape of which corresponds to the shape of the later inner ring 2, is clamped into a machine tool, not shown, e.g., a milling machine. During the following processing, the blank, that is to say the later inner ring 2, rotates about the central axis M thereof at a cutting speed v.sub.e. The machining of the blank while it is clamped in the machine tool includes machining of the roller body track 6.

[0042] In the example sketched out in FIGS. 1 to 3, the rolling bearing 1 is only sealed on one side. Accordingly, the rolling bearing 1 has only a single cylindrical surface 10, Which functions as a sealing face within the fully assembled rolling bearing 1 (FIG. 3). The surface structuring 11 of the surface 10 indicated in FIG. 2 is also given in the exemplary embodiment according to FIG. 4. The surface structuring 11 has the form of numerous depressions 12. The roughness depth R.sub.t of the structured surface 10 here is in the range from 3 to 5 μm.

[0043] A tool 13 in the form of a high-feed milling cutter 14 is used to produce the depressions 12. The tool 13 is installed on the machine tool.

[0044] The high-feed milling cutter 14 can be oriented in an XYZ coordinate system (see FIG. 1) in relation to the central axis M in the XY plane and/or in an angled manner, seen in the YZ plane. The high-feed milling cutter 14 is advanced axially in the direction of the Y-axis, that is, material is removed by being advanced in the direction of the axis of rotation M.

[0045] To produce the surface structuring 11 of the inner ring 2 according to FIG. 4, the tool 13 is, for example, moved slowly and evenly radially from the inside to the outside or from the outside to the inside, The depressions 12 thus generated theoretically lie on a spiral line. If, on the other hand, the tool 13 is moved with a comparatively high frequency between a first extreme point, which lies radially inward, and a second extreme point, which represents the radially outer boundary of the surface 10, then those waveforms of the surface structuring 11 arise first which lie in a single plane, namely the plane of the surface 10. In the course of several revolutions of the inner ring 2, these waves overlap several times, in principle comparable to the exemplary embodiment according to FIG. 1, so that also in this case a high uniformity is achieved in the distribution of the depressions 12 within the surface 10.

[0046] FIG. 5 shows in the representations 5 a)-5 e) five different surface structurings 11a to 11e formed by means of high-feed milling on flat surfaces made of metallic material, in particular steel. Different machining parameters during high-feed milling are responsible for the appearance and the respective roughness depths achieved of each surface structuring 11a to 11e. For each surface structuring 11a to 11e, the parameters cutting speed v.sub.e, axial infeed a.sub.c, radial infeed a.sub.p, feed per tooth f.sub.z and setting angle β.sub.f are given below, which were used to form them with identical milling cutters.

[0047] FIG. 5a): [0048] v.sub.c=100 m/min [0049] a.sub.e=1 mm [0050] a.sub.p=100 μm [0051] f.sub.z=0.05 mm [0052] β.sub.f=0.1°

[0053] FIG. 5b): [0054] v.sub.c=100 m/min [0055] a.sub.e=3 mm [0056] a.sub.p=100 μm [0057] f.sub.z=0.3 mm [0058] β.sub.f=5°

[0059] FIG. 5c): [0060] v.sub.c=100 m/min [0061] a.sub.e=1 mm [0062] a.sub.p=100 μm [0063] f.sub.z=0.1 mm [0064] β.sub.f=0.1°

[0065] FIG. 5d): [0066] v.sub.c=100 m/min [0067] a.sub.e=1 mm [0068] a.sub.p=100 μm [0069] f.sub.z=0.15 mm [0070] β.sub.f=0.1°

[0071] FIG. 5e): [0072] v.sub.c=100 m/min [0073] a.sub.e=1 mm [0074] a.sub.p=100 μm [0075] f.sub.z=0.3 mm [0076] β.sub.f=0.5°

[0077] The appearance of a sealing face can be designed in such a way that parallel processing tracks 110 of a high-feed milling cutter 14 are shown in a longitudinal structure that runs in the direction of the feed direction, with arc-shaped or partially circular milling tracks 111 within such a processing track 110 as a transverse structure, which essentially is formed perpendicular to the longitudinal structure, can be seen [compare FIGS. 5a), 5b), and 5e)]. However, more uniform surface structurings that do not show a pronounced longitudinal structure can also be produced [compare FIGS. 5c), 5d)].

[0078] The XYZ coordinate system, which is shown as an example for illustration 5e), is intended to clarify the machining parameters. The cutting speed v.sub.c is given in the cutting direction along the Z-axis, the axial infeed a.sub.e is given in the direction of the Y-axis, the radial infeed a.sub.p is given in the direction of the X-axis, the feed per tooth is f.sub.z indicated in the direction of the Z-axis, and the angle of incidence β.sub.f of the axis of rotation R of the high-feed milling cutter 14 (see FIG. 1) is indicated with respect to the XZ plane.

[0079] Through a few experiments with variation of the machining parameters during high-feed milling, different surfaces that are suitable for use as surface structuring for a sealing face can be generated. It should be noted, however, that different designs of the milling cutter used with regard to the number of cutting edges (or number of teeth) and cutting edge arrangement also have an influence on the surface structure achieved. Using the same processing parameters, but different milling cutter geometries, different surface structures are achieved. However, the average person skilled in the art is easily able to find suitable surface structures for sealing faces of bearing rings with the aid of a few experiments while changing the machining parameters during high-feed milling with a given milling cutter.

REFERENCE NUMERALS

[0080] 1 Rolling bearing

[0081] 2 Inner ring

[0082] 3 Outer ring

[0083] 4 Flange

[0084] 5 Roller body

[0085] 6 Track of the inner ring

[0086] 7 Track of the outer ring

[0087] 8 Seal

[0088] 9 Sealing lip

[0089] 10 Surface

[0090] 11, 11a-e Surface structuring

[0091] 110 Processing track

[0092] 111 Milling track

[0093] 12 Depression

[0094] 13 Tool

[0095] 14 High-feed milling cutter

[0096] M Central axis

[0097] R Axis of rotation

[0098] X X coordinate

[0099] Y Y coordinate

[0100] Z Z coordinate