SINGLE-PHASE INDUCTION MOTOR, AND ROTOR ASSEMBLY DEVICE

PROBLEM TO BE SOLVED: To suppress the occurrence of electromagnetic sound by equipping this device with a main winding, an auxiliary winding, a plurality of operation capacitors connected to the auxiliary winding, a relay for turning on or turning off the operation capacitor, according to the operation load, and a rotor where the side of vacant space (periphery side) of the slot is open. SOLUTION: This device is equipped with a main winding 2 wound around the stator of a single-induction motor 1, an auxiliary winding 3, a first operation capacitor 4 which has a current always applied during the current application of the single-induction motor 1, a second operation capacitor 6 which has a current applied only at high torque operation and is cut off with a relay 5 at low torque operation, a start capacitor 7, and a PTC thermistor 8 which is a start relay for cutting off the start capacitor 7 immediately after start. Moreover the rotor of open slot is used for the single-phase induction motor 1. As a result, even at high torque operation large in load (relay is on and currents are applied to both the first operation capacitor 4 and the second operation capacitor 6), the occurrence of electromagnetic sound can be suppressed.