| 摘要 |
PROBLEM TO BE SOLVED: To resolve the problem in which vibrations of a fan motor in operation are transmitted to a fan and generate acoustic noise that is rather annoying to an ear, particularly at low speeds.SOLUTION: An electric fan 1 has an electric motor 5 driving an axial fan. The fan has a cup-shaped hub 9, and the hub has a front wall 9a, and a side wall 9b from which there extends a plurality of outer blades 10. The motor has an outer rotor including a rotor cap 8 to which the front wall of the hub is attached. From an inner surface 9d of the hub and/or from an outer surface of the rotor cap, there extend protruding portions 20, 21 which, when the fan performs an oscillation of predetermined extent with respect to the rotor, impact the rotor cap and/or the hub, limiting the extent of the oscillation of the fan with respect to the rotor. |
