EXPLOSION-TIGHT SEAL FOR ELECTRIC MOTOR BEARING UNIT Russian patent published in 2004 - IPC

FIELD: electromechanical engineering; electrical machines using explosion-tight enclosure.

SUBSTANCE: explosion-tight seal of motor bearing unit has set of separate flat sealing rings made of nonferrous metal and installed in annular drilling of seal base made of nonmagnetic material on electrical machine shaft, slit joints being formed between these rings and between each ring and mentioned components of bearing unit; it also has butt-end lid with annual axial projection and bolts fastening butt-end lid to seal base; pairs of radially magnetized permanent magnets facing each other with their like-polarity poles are installed on external cylindrical surface or in annular drilling of seal base, each ring being flush mounted with the latter; these pole pairs are spaced apart through distance not to exceed magnet width as measured over arc of seal base bore; magnets of adjacent rings are facing gap by their unlike-polarity poles.

EFFECT: enhanced reliability of electric motor.

1 cl, 2 dwg