| 摘要 |
PROBLEM TO BE SOLVED: To reduce a noise of a blower by preventing a dynamic unbalance from occurring in a fan. SOLUTION: A round shaft part 124 having a cross section symmetric with respect to the center of figure G1 and a D part 125 having a D shaped cross section are provided, and a center of gravity G0 of a fan 110 is arranged so as to be located in the round shaft part 124. The D part 125 positions a fan 110 relative to shaft 123 and serves as a guide part when the round shaft part 124 is inserted into a first hole part 113. As forces acting on the shaft 123 and the first hole part 113 serve symmetric, secular changes of the shaft 123 and the first hole 113 are symmetrical with the center of figure G1 . Accordingly, occurrence of dynamic unbalance is hard to be generated on the fan 10, a vibration of the fan 110 can be suppressed and a noise can be reduced. |
