| 摘要 |
<p>In a variable speed controllable induction motor which has a unitary rotor (2) having a plurality of rotor cores (2A,2B) provided thereon with rotor conductive members (5) short-circuited by resistive members (r), a plurality of stators (25,26) surroundingly facing the respective rotor cores (2A,2B) and a phase shifter (PD) producing phase differences between the voltages induced on separate portions of the conductive members (5), there is provided an air mover (50) which forces in the ambient air into internal air passages formed between the rotor cores (2A,2B) and between the stators (25,26) and the machine frame (20) to radiate heat from and cool the resistive members (r) and forces the warmed air out of the machine frame (20). The air mover (50) is provided with a control device (60) which is operated on the basis of information such as a rotation speed of the rotor (2), phase differences produced by the phase shifter (PD) and temperatures taken within the machine frame (20).</p> |
