| 摘要 |
PROBLEM TO BE SOLVED: To provide a thin centrifugal fan capable of reducing noises.SOLUTION: A centrifugal fan has such a structure in which an impeller 30 is arranged above a lower casing 21. The impeller 30 comprises: an upper shroud 31; a lower shroud 41 to which a rotor 63 of a motor is fixed; and a vane 51 arranged between the shrouds. The centrifugal fan exhausts air introduced from a suction port 33 of the impeller 30 to a side of the impeller 30 together with rotation of the impeller 30. Both of the rotor 63 and the lower shroud 41 pass through an upper end 35 inside the suction port 33 while a center A2 is positioned on a straight line L parallel to a rotation shaft, and is positioned on an outer side than a circle C2 passing through an outer peripheral end 45 of the lower shroud 41, on a cross section passing through the rotation shaft of the impeller 30. A radius R2 of the circle C2 is 80% of a distance from the upper end 35 to a surface of the lower shroud 41. |
