抄録
The hydrostatic gas bearing can achieve high accuracy and high rotation speed. However, the load capacity of the hydrostatic gas bearing is generally much smaller than that of mechanical rolling contact bearings. Therefore, if the static imbalance of the rotor is large, the rotor easily vibrates although the rotating speed is low. This is serious problem because contact between the rotor and the bearing may cause fatal damage to them. In order to solve this problem, the hydrostatic gas bearing with asymmetrically arranged gas supply holes has been proposed and developed. By this bearing mechanism, the load capacity increased, and the unbalanced rotor was operated at higher rotation frequency than supported by conventional bearing. Also the rotation frequency could be increased by increasing the gas supply pressure. That was demonstrated by numerical calculations and experiments. From this result, we thought that this bearing can theoretically reduce rotor vibration during rotation frequency modulation by controlled gas supply pressure. That was verified by the rotation experiment. As the result, the proposed bearing is possible to safely rotate the unbalance rotor during rotation frequency modulation. Also, this bearing were able to reduce rotor vibration at higher and wider rotation frequency range by arranged more gas supply hole to loaded side of the unbalance rotor. From above process, the effectiveness of this bearing mechanism was demonstrated.
