| 摘要 |
PURPOSE:To increase the cooling effect by providing Venturi tube on the exhausting side of a cooling hole of a rotor, and generating a ventilating action with the exhausting side pressure being negative against the intake side pressure. CONSTITUTION:The rotor 6 is arranged with a gap G being provided between said rotor 6 and a stator 5. A ventilating hole 7 for cooling is provided along a shaft. The exhausting side of the ventilating hole 7 is formed by the Venturi tube which is opened in the direction of the periphery. In this constitution, when the rotor 6 is rotated in the direction indicated by the dotted arrow line, the pressure at the exhausting side of the ventilating hole 7, that is the Venturi tube, becomes low based on the Bernoulli's theorem. Therefore, air flows from the intake side to the exhausting side in the ventilating hole as shown by the solid arrow lines, and the rotor 6 is cooled. |
