Patent ID: 7504755

Claim:
A rotor of a synchronous induction motor comprising: a rotor iron core formed by laminating a plurality of electromagnetic steel sheets; at least one pair of slits provided at each of the plurality of electromagnetic steel sheets to form a magnetic pole projection so as to obtain a d axis that is a direction in which magnetic flux easily flows and a q axis that is a direction in which magnetic flux hardly flows; a plurality of slots connected to the slits and provided adjacent to an outer circumference of the electromagnetic steel sheets to generate an induction torque; conductive material filled in at least the slots among the slits and the slots; and a shaft which is an axis of rotation provided at a center part of the rotor iron core; and a gas vent hole on the d axis, wherein a slit next to the shaft has a shape which is projected along a circumference of the shaft and a circumference of the gas vent hole so as to maintain passability of magnetic flux in a direction of the d axis and increase unpassability of magnetic flux in a direction of the q axis.