Magnetic fluid sealing device

The invention relates to a magnetic fluid sealing device. The device comprises an outer ring, a magnetic field generation unit and a sealing ring, wherein a rotating shaft can pass through the outer ring; a sealing chamber is formed in the outer ring; the magnetic field generation unit is arranged in the sealing chamber of the outer ring and encircles the rotating shaft; a gap is formed between the magnetic field generation unit and the rotating shaft and used for filling magnetic fluid; the magnetic field generation unit can generate a magnetic field with magnetic force to keep the magnetic fluid in the gap; the sealing ring is arranged in the sealing chamber of the outer ring and contained in radially separated outer periphery and inner periphery; the rotating shaft can pass through theinner periphery of the sealing ring; an arc lip part extends from the end of the inner periphery of the sealing ring, which faces the outer ring; and the lip part can prevent a conveying medium or cooling liquid outside the s