PURPOSE: To reduce a noise generated when a disk plate is rotated and to improve a life and reliability of the disk plate by a method wherein a drain water dispersion vane is arranged only at one side surface of the disk plate.
CONSTITUTION: A disk plate 10 fixed to an electric motor 6 is provided with a drain water dispersion vane 10b only at the side of the electric motor. The other surface of the disk plate is not provided with a vane and is formed as a flat shape. When a thickness of the disk plate and a depth of the vane are set as the same values as those of the prior art, that is, the relation of X1=X2 and Z1=Z2 is defined, a thickness of the vane is made thick. That is, it results in a relation of Y2>Y1. The disk plate used in the drain water during cooling operation, so that as apparent from a relation of Y2>Y1 and a thickness of the wall is thick and the reliability of the disk plate is improved. Further, since the disk plate 10 is provided with the vane 10b only at one side thereof, a resistance when the drain water is scraped up is decreased lower than that of the disk plate 7, so that a noise is reduced.
TOGAMURA TOMIYASU
IIDA KENJI