ROTOR FOR INDUCTION SHORT-CIRCUITED ELECTRIC MOTOR Russian patent published in 1997 - IPC

FIELD: electric engineering. SUBSTANCE: device has alternating covered slots which have two types of shapes and areas. First slot is shaped as bottle with necks in upper and lower parts at height h from outer rotor surface. Second slot is shaped as bottle with neck in lower part and funnel in upper part. Ratio of areas at said height for first and second slots varies from 1.0 to 2.5. Slots have upper funnel parts and neck lower parts. These parts are located below height h. Sizes of these parts provide ratio of total slot area from 1.0 to 0.4; height of joint above first slot is greater than that above second one. H is penetration depth of electromagnetic wave for static rotor. EFFECT: improved characteristics for starting and operating modes. 1 dwg