INDUCTION MOTOR Russian patent published in 2001 - IPC

FIELD: electrical engineering; motors for domestic and industrial drives including pump drives. SUBSTANCE: motor has wound stator press-fitted into frame with its winding assembled of separate coils, core mounted on steel shaft of rotor with slots to receive rotor winding, front and rear endshields, shaft-mounted fan with shroud, terminal box for terminal unit in the form of terminal strip for connecting motor winding to supply mains. Novelty is that drive end of shaft has central variable-section hollow to receive pump drive stepwise increasing towards hollow end distant from shaft end which is blind and has conical surface; in this way drive end of shaft does not protrude beyond motor frame; central hollow length from shaft end to origin of its conical section is 0.16-0.20 of total length of shaft; diameter of narrow portion of central hollow is 0.55-0.65 of shaft diameter and that of its wide section is 0.6-0.67 of shaft diameter. In vicinity of mentioned hollow shaft has internal longitudinal blind keyway running from shaft end, its length being 0.49-0.71 of hollow length from shaft end to origin of its conical section; keyway depth is 0.2-0.24 of shaft wall thickness in vicinity of narrow part of hollow. Through hole is provided in shaft wall perpendicular to blind longitudinal keyway that communicates with the latter, its diameter being at least by 1.2 times greater than width of longitudinal blind keyway. Through bore diameter in front endshield on drive end of shaft where there is no bearing is greater by at least two times than diameter D_r.es (diameter of through bore in rear endshield); outer surface of front endshield has annular seat with holes for securing pump flange. EFFECT: simplified design due to dispensing with front bearing; reduced metal input due to shortening of shaft length. 12 cl, 9 dwg