| 摘要 |
PURPOSE:To obtain stable operation for changing of pressure difference under broad pressure difference condition by providing a magnetic bearing consisting of magnetic plate and an electromagnet attracting the magnetic plate at a high vacuum side of a turning axis, to a multi-staged axial flow turbine consisting of the invented radiation device, and by detecting the pressure difference and controlling electric current supplied to the electromagnet according to the difference. CONSTITUTION:A multi-staged axial flow turbine 6 is provided by a magnetic bearing 15 having a magnetic plate to compensate pressure difference between pressures applied to high and low vacuum sides of a turning axis, and an electromagnet, at a high vacuum side of the turbine. That is, by controlling the electromagnet, reverse electromagnetic force against the pressure applied to the turning axis is given to mitigate load on the turning axis. Controlling of the electromagnet is carried out by measuring the high and low vacuum sides by vacuum meters 17 and 18, by calculating pressure difference by a detection part 16a and by supplying electric current according to the difference, to the electromagnet by the controlling part. By this procedure, the radiation device 1 can be used under broad pressure difference condition and can obtain stable performance under ever changing pressure. |
