WE CLAIM:
[Claim 1]
A propeller fan comprising:
a shaft disposed on a rotation axis; and
a blade disposed adjacent to an outer circumferential surface of the shaft, the blade having a leading edge and a trailing edge,
wherein at least one of the leading edge and the trailing edge has a notch,
wherein the notch includes a pair of side edge-parts forming an acute included angle and bottom edge-part located between the pair of side edge-parts, and
wherein the bottom edge-part includes at least one first protrusion having an obtuse included angle. [Claim 2]
The propeller fan of claim 1, wherein the first protrusion is located in middle part of the notch in a radial direction of the blade. [Claim 3]
The propeller fan of claim 1 or 2, wherein the first protrusion includes one or more arcs. [Claim 4]
The propeller fan of any one of claims 1 to 3,
wherein the notch includes two recesses arranged on opposite sides of the first protrusion, and
wherein at least one of the two recesses has an obtuse included angle. [Claim 5]
The propeller fan of any one of claims 1 to 4, wherein the at least one first protrusion of the bottom edge-part comprises a plurality of first protrusions. [Claim 6]
The propeller fan of any one of claims 1 to 5, wherein one of the pair of side edge-parts is located adjacent to an outer circumference of the propeller fan and includes a second protrusion.