| 摘要 |
PROBLEM TO BE SOLVED: To provide a propeller fan having high efficiency and making only a small noise. SOLUTION: This propeller fan has a curved surface determined by an r coordinate value, aθcoordinate value and a z coordinate value where coordinates in circular cylindrical coordinates of which a rotational axis of the propeller fan is z axis are (r,θ, z) to be a base shape of blade surface of the propeller fan and has the blade surface of the propeller fan formed by a curved surface obtained by enlarging or reducing the base shape in at least one of r,θand z directions. This die for forming propeller fan has a surface of a part forming the blade surface of the propeller in the die formed by a curved surface obtained by enlarging or reducing the base shape in at least one of r,θand z directions.
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