| 摘要 |
PURPOSE:To prevent magnetic grains from flowing into a lower chamber so as to prevent magnetic fluid from the degradation of performance by forming an opening at the upper chamber side of an orifice to be directed horizontally or downward from the horizon. CONSTITUTION:A space 20 is defined into a upper stage lower chamber 23 having large volume, an intermediate stage lower chamber 24 having small volume and a lower stage air chamber 25 by a first partition wall member 21 made of a metal member and a second partition wall member 22 made of a flexible elastic member. A coil 44 is connected to a voltage applying device and the intensity of magnetic field of an orifice 42 is regulated by controlled exciting current supplied from the voltage applying device. The upper chamber 23 side end of an annular orifice member 41 is bent and formed such that the opening section 40a of an orifice 40 is directed vertically downward, and the upper chamber 23 side end of each orifice member 43 is bent and formed such that the opening section 42a of the orifice 42 is directed vertically downward. Since sedimented ferrite grains 30a are uniformly dispersed, magnetic fluid 30 can be prevented from the degradation of performance. |
