| 摘要 |
PURPOSE:To prevent magnetic fluid from scattering by inserting a cylindrical ring provided on the inner periphery with a projecting ring-shaped baffle plate into opposed throttle portions at one end of inner and outer peripheral yokes to fill sealingly magnetic fluid in a gap at the inner peripheral yoke side. CONSTITUTION:Ends of inner and outer peripheral yokes 1a, 1b sandwich a magnet 6 to form a magnetic circuit circumscribed a shaft 2 through a support 7. The other ends of the inner and outer peripheral yokes are formed with opposed throttle portions 1a', 1b' and into a gap between these portions is inserted an end of a cylindrical ring 5 having the other end fixed to a rotor 4 circumscribed a bearing 8 of the shaft 2. Also the cylindrical ring 5 between the magnetic circuit and a bearing 8 of the shaft 2 is provided on the inner peripheral surface with a projecting ring-shaped baffle plate 5b the end of which is opposed to the shaft 2 to form a gap. Magnetic fluid 3 fills and seals a gap between the cylindrical ring 5 and the throttle portion 1a' of the inner peripheral yoke 1a. Thus, the magnetic fluid can be not only prevented and restrained from scattering and vaporization but also provide exothermic reduction. |
