| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a propeller fan capable of reducing the noise emission from a region where it operates actually and suppressing the drop of the fan efficiency. <P>SOLUTION: The propeller fan is equipped with a hub 2 rotated by a motor and a plurality of vanes 1 extending outward in the radial direction from the hub 2 and sending the wind in the direction of a rotary shaft 3, wherein the leading edge of each vane is inclined to upstream side at a constant, first forward tilting angle greater than 0°in the first region ranging from the hub 2 to the bending point in the middle through the radial direction, and in the second region from the bending point to the periphery of the vane, is inclined to upstream side further from the first forward tilting angle, while the forward tilting angle of the trailing edge of the vane is made approximately identical to a constant, second forward tilting angle of the vane leading edge of the line connecting the hub 2 and the vane periphery. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
