Abstract
Load is an important factor which has an influence to life cycle and performance in rolling bearing. The life cycle becomes shorter, and the sound and vibration intend to increase when a large load is applied. On the other hand, too small load causes a rotational instability and a shortage of rigidity. For a large load, dynamic and static rated loads are regulated, then applicable load is basically set. However, there are no regulations for the minimum load to stabilize the rotation of bearing. Therefore, in this research, the authors considered experimentally the necessary minimum combined (radial and axial) load for small ball bearing, with a parameter of increment in revolving skid of rolling element. As a result, it was clarified that the revolving skid of rolling element did not increase and stable rotation could be persisted when the dynamic equivalent load is almost 1% of the dynamic rated load.
