| 摘要 |
PURPOSE:To prevent the damage of an air pad and a static pressure bearing, by a method wherein, when main gas supply is interrupted by service interruption and the like, and at the same time, pump means for gas recovery are interrupted, a gas recovery inlet of the static pressure bearing is opened to the atmospheric air. CONSTITUTION:When main gas supply is interrupted, a switching means 314 connects a static pressure bearing inlet to a backup supplying means 320 side by the output of a main gas supply interrupting means 316, so that gas is continuously supplied to the static pressure bearing by the backup supplying means 320, and the static pressure bearing continues normal operation. In the case of service interruption, the interruption of main gas supply and that of gas recovery are detected, and backup gas supply is performed. Further, by detecting the interruption of gas collection, an opening means 331 is operated, and a static pressure bearing collecting inlet is opened to the atmospheric air. Thereby pumps 333, 335 for air recovery are interrupted, so that the air withdrawal caused by service interruption and the like is prevented, and the damage of an air pad 303 and a transfer guide can be prevented. |
