The present invention relates to a method of machin¬ ing a component of a bearing.

In the state of the art it is known to improve the performance of a bearing comprising bearing rings by using bearing rings with machined raceways. This machining usually comprises the step of honing. It is also known to machine rollers for roller bearings.

The object of the present invention is to further improve the performance of a component of a bearing, said com- ponent being a bearing ring and/or a roller.

To this end the method according to the invention is characterized in that a texture is formed on the component.

The component may be the raceway of a bearing ring, and in case of roller bearings, the raceway and/or rollers. It has been found that a surface texture can influ¬ ence the lubrication of raceways, in which way it is possible to control the lubrication and thus improve properties like life-span.

According to a preferred embodiment the texture is formed by electrochemical machining.

Electrochemical machining offers a versatile way to form textures on a component of a bearing.

The invention also relates to an electrode for elec¬ trochemically machining said component in accordance with the invention. Such an electrode is characterized in that the electrode has a cylindrical shape, the cylindrically shaped surface of said electrode being covered with electrically con¬ ducting spots forming a texture pattern.

Moreover, the invention relates to a method of manu- facturing an electrode.

According to one embodiment, the method is character¬ ized in that an electrically conducting brush with radially extending, conducting bristles is treated with non-conducting material such that the bristles are covered over their length with non-conducting material, whereas the radially extending

end faces of the bristles are free of non-conducting material and the end faces determine a cylindrically shaped electrode.

According to another embodiment the method is charac¬ terized in that an electrically conducting cylinder is coated with a non-conducting film, leaving spots on the surface of the conducting cylinder uncoated to provide a texture pattern.

A further method of manufacturing an electrode accor¬ ding to the invention is characterized by coating an electri¬ cally conducting cylinder with a non-conducting film, and removing non-conducting film locally to create uncoated spots on the surface of the conducting cylinder to provide a texture pattern.

Moreover, a method of manufacturing an electrode according to the invention is characterized in that an elec- trically conducting cylinder is provided with spots of etching resistant material, the cylinder is etched and subsequently provided with a non-conducting film after which the spots of etching-resistant material are removed, exposing the electri¬ cally conducting cylinder. The invention will now be elucidated with the aid of the drawing, illustrating the invention by way of example.

Fig. 1 is a perspective view of an electrode with a texture pattern.

Fig. 2 is a side view of another embodiment of the electrode.

Fig. 3 is a schematic view of the electrochemical machining of a raceway of a bearing ring.

Fig. 1 shows an electrode 1 with a pattern on its surface consisting of electrically conducting spots 2. With spot is meant any local element, whether circular, linear or cross-hatched etc., in or protruding from the surface of the electrode 1. The electrode 1 may be an electrically conducting cylinder, which cylinder is covered over its surface with an electrically non-conducting layer, leaving spots 2 of the electrically conducting body exposed.

Fig. 2 shows the electrode 1 shown in Fig. 1 provided over the circumference of the cylinder with ribs 3, 3' to form, together with the component 4 here a raceway 4, and the cylindrically shaped surface of the electrode 1, a narrow gap 6 for passing electrolyte during electrochemical machining.

Thus it is possible to maintain a constant gap width and obtain consistent results.

Fig. 3 shows schematically a method of electrochemi- cally machining the raceway 4 of a bearing ring 5. The bearing ring 5 may be a bearing ring 5 for any type of bearing. The bearing ring 5 and the electrode 1 together form a gap 6 through which electrolyte A is passed, delivered by a nozzle 7. As shown by the arrows, the electrode 1 and the bearing ring 5 are rotated in relation to each other. The relative speed is preferably such that the speed in metres per second is equal there where the distance between the spot 2 on the electrode 1 and the raceway 4 is at a minimum. With the embodiment of the electrode shown in Fig. 2 it is simple to synchronize the motion if the ribs 3, 3' are adjacent to the raceway 4 of the bearing ring 5 and the height of the ribs 3, 3' is small compared with the radius of the electrode 1.

By way of example an electrode 1 can be manufactured starting with an electrically conducting brush, for example a metal brush, with radially extending, conducting bristles. The brush is embedded in a non-conducting resin and subsequently honed to a cylinder, with the end faces of the bristles exposed.