Rotor for an induction motor

A rotor adapted for use in an induction motor, the rotor comprising a core having a central hole extending axially therethrough and adapted to receive a shaft;

• a plurality of spaces formed in the core in circumferentially spaced relationship, each space filled with a non-ferrous metal;
• at least one blowhole extending through the non-ferrous metal of each of the spaces, whereby each blowhole is able to conduct cooling air through the core;
• each of the spaces including radially spaced outer and inner sides and a pair of circumferentially spaced sides;
• each of the circumferentially spaced sides interconnecting the outer and inner sides;
• the outer side having a longer circumferential dimension than the inner side;
• each of the spaces having a maximum radial dimension extending between the outer and inner sides thereof;
• the core defining a first distance extending radially from an outer edge of the central hole to an outer periphery of the core, and a second distance extending radially from the outer edge of the central hole to the outer side of each of the spaces;
• the second distance being about one-half of the first distance;
• the maximum radial dimension of each space being about one-half of the first distance.