Process for deriving the contact geometry for raceways and rollers of a roller bearing

摘要

The contact geometries, that is profiles and taper, for the raceways and rollers of a tapered roller bearing are designed for specific load cycle and are configured to provide rnniform life along the lines of contact between the raceways and rollers. At the outset, the roller loads along each raceway and the external misalignment between the cup and cone are known for each segment of the load cycle, as is the duration of each segment of that cycle. To derive suitable contact geometry, initial contact geometries are selected somewhat arbitrarily for the cup and cone raceways and for the roller side faces. Using the initial contact geometrics the internal bearing misalignments, that is the misalignment between the cup raceway and the rollers and the misalignment between the cone raceway and the rollers, are computed for each segment of the load cycle. From the internal misalignments so derived, modifications to the selected contact geometries are computed to create altered contact geometries which theoretically produce substantially uniform life along the lines of contact between the raceways and rollers. But these altered contact geometries produce different internal misalignments for the various segments of the load cycle, so new internal misalignments are calculated for the altered contact geometries. The new internal misalignments require further modifications to the raceways to effect uniform life along the lines of contact between the raceways and rollers, and this results in other altered contact geometries which in turn further changes the internal misalignments. The foregoing procedure of determining internal misalignments and modifying contact geometries is repeated over and over again until the iteration substantially converges to a solution. The contact geometries that exist at convergence are ground into the actual bearing.