MAGNETIC-LIQUID SEALING Russian patent published in 2018 - IPC F16J15/43 

FIELD: seals.

SUBSTANCE: invention relates to the sealing equipment, and can be used for the rotational inputs into closed volumes sealing. Magnet and liquid sealing (MLS) comprises housing 1, movable shaft 4, bearings 2, 3 and magnetic system 5. In general case, the latter contains movable magnetic circuits – shaft 6 bushings – and fixed 7 magnetic circuits, made of magnetically conductive (soft magnetic) materials, mechanically connected to the shaft and the housing, respectively. In the case of ferromagnetic shaft execution, the shaft bushing may be absent. In at least one of the magnetic circuits the annular grooves 8 are made, in which permanent magnets 9 in the form of disks or rings, or prisms are arranged. Magnets have the same of magnetization direction in each groove, and the opposite one in adjacent grooves. These grooves divide the magnetic circuits into the pole tips 10 zones and the tightly connecting the pole tips thin bridges 11 zones. Facing each other magnetic circuits surfaces are spaced apart from each other at the working gap distance, in which the magnetic fluid 12 is located. Entering into the working gap magnetic cores surfaces are made smooth and therefore have uniform magnetic conductivity of the facing the gap surface layers, at least on the bridges thickness. Magnetic field in the working gap required heterogeneity is provided by not homogeneous in magnetic conductivity internal structures, for example, grooves 8 of at least one of the magnetic cores. Due to the magnetic field distribution inhomogeneity in the gap, the magnetic fluid forms maintaining the required pressure drop liquid annular plugs.

EFFECT: in the design and manufacturing technology simplification, as well as in the magnetic fluid during the shaft rotation losses reduction.

1 cl, 7 dwg