Rolling element bearing having at least one rolling element having a hardness greater than the hardness of the other rolling elements

摘要

A rolling element bearing includes an outer ring and an inner ring which enclose a bearing space containing rolling elements. The rings are made of steel. At least one of the rolling elements comprises, at least partially as a zirconium material which is harder and stiffer than the material of the other rolling elements which are comprised of steel. Walls of indentations which are formed in the rings by solid contamination particles between the rings and one of the rolling elements having about the same hardness as the rings, are compressed as soon as the zirconium material rolling element with a substantially higher hardness than the rings overrolls the walls. Thereby, the smooth characteristic of the raceways is restored. Only small holes are left in the rings, which do not have a negative influence on the running properties of the bearing. In these small holes, minute quantities of lubricating oil are collected, which help the lubrication of the rolling elements in case of oil starvation.