| 摘要 |
PURPOSE:To make the supply of magnetic fluid automatically and promptly operable, even without operating a process to lower the gas pressure with a running ceased of the rotary machine. CONSTITUTION:Two ring-shape ball blocks 2, that surround a rotary shaft 1, are supported to inner circumferential face of a fixed casing 4, and a magnetic unit cylinder 6, facing to inner circumferential face of the above described block 2, is engaged to be installed to the rotary shaft 1, and in the portion of a ring-shape fine protrusion 7 of this cylinder 6, is intermediately placed a magnetic fluid 15 to perform the sealing operation. In this case, with a seal of the portion of the magnetic fluid 15 damagd by any reason and the pressure of a space 11, 13 equalized to transmit an elimination of pressure difference between pressure detectors 22, 23 to a comparator circuit 21, a pluse is transmitted from a pulse transmitter 20, and fed to a pulse motor 18 through an amplifier 19. In this way, an injection device 16 is actuated till a pressure sensor 24 detects a sealing pressure reaching the prescribed value, and the magnetic fluid is fed from a feed path 14. |
