VACUUM MAGNETIC-LIQUID SEAL OF ROTATING SHAFT Russian patent published in 2022 - IPC F16J15/40 

FIELD: sealing equipment.

SUBSTANCE: invention relates to the field of sealing equipment; it can be used in industrial vacuum installations for sealing of rotating shafts. In a case tightly attached to a vacuum chamber, a vacuum magnetic-liquid seal of a shaft rotating on bearings is placed, consisting of a permanent magnet and two assembled pole tips, each of which consists of stationary outer and inner rings made of magnetically conducting material and having cylindrical protrusions in a lower part, inner sides of which with annular grooves applied to them are directed towards each other. At the same time, an inner movable ring rests against protrusions of rings, made of elastic non-compressible magnetically conducting material, having a cylindrical protrusion in a lower part, side surfaces of which form gaps of a constant value of 0.1 mm with vertices of annular grooves of cylindrical protrusions of rings, and on which magnetic liquid is collected. An inner cylindrical surface of the protrusion, in turn, forms a working gap of a variable value with vertices of annular grooves made on the shaft and filled with magnetic liquid. The permanent magnet with parts of pole tips, adjacent to it, and the rotating sealed shaft made of magnetically conducting steel form a closed magnetic circuit. An outer surface of the inner movable ring has a semicircular shape, a vertex of which forms a variable limiting gap with the inner cylindrical surface of the case, equal to 0.4 mm, when assembling the seal. At the same time, the formed variable free cavity in pole tips, through channels in the case, is connected to a sealed vacuum pipeline.

EFFECT: invention is aimed at an increase in the reliability, operational resource, and expansion of operational capabilities of a vacuum magnetic-liquid seal, when operating with different rotational frequencies and circular speeds of rotation of a shaft due to the creation of gradual automated adjustment of a value of a working gap and a friction moment in it.

2 cl, 1 dwg