Rotor cooling device for motor for electric vehicle

摘要

PPROBLEM TO BE SOLVED: To provide a device for cooling a rotor of a motor for an electric vehicle that properly controls the liquid surface height of a liquid coolant pooled in a casing according to the number of revolutions of the motor. PSOLUTION: The liquid coolant is made to flow in a driving shaft of the motor and a rotor shaft connected to the driving shaft. To the rotor, provided are first and second opening and closing members and. The first opening and closing member is open when the rotor is in a stop state and closed until the number of revolutions of the rotor reaches the first predetermined number of revolutions after the rotor starts rotating, so that the liquid coolant is held in the rotor shaft. Conversely, the second opening and closing member in a closed state is opened until the rotor reaches the second predetermined number of revolutions larger than the first number of revolutions to release the liquid coolant in the rotor shaft into the casing. PCOPYRIGHT: (C)2006,JPO&NCIPI