To obtain an axial flow fan that reduces a blade passing frequency sound while keeping a ventilation performance and securing the strength of the blades.
In the axial flow fan 80 including a boss 2 attached to a rotary shaft of a motor and a plurality of blades 10 that are radially disposed on the outer periphery of the boss 2 and send air in the axial direction, when, on a projected figure of the axial flow fan 80 on a plane orthogonal to the rotary shaft, a position of the rotation shaft is denoted by O, a boss-outer-periphery blade-chord-line midpoint of each of the blades 10 is denoted by Pb and a blade-outer-edge blade-chord-line midpoint of the each of the blades 10 is denoted by Pt, the boss-outer-periphery blade-chord-line midpoints Pb of the respective blades 10 are arranged at substantially equal intervals in the peripheral direction on the boss outer periphery, and an angle δθt formed by a straight line O-Pb and a straight line O-Pt at least in a part of the blades 10 is different from an angle δθt formed by a straight line O-Pb and a straight line O-Pt in the other blades 10.
ARAI TOSHIKATSU
MORI ATSUSHI
| JPS5711299U | 1982-01-20 | |||
| JPH07269460A | 1995-10-17 | |||
| JPH05223093A | 1993-08-31 |