Abstract: An air conditioner includes an outdoor unit that includes a compressor configured to compress a refrigerant, a condenser configured to condense the compressed refrigerant, and a blowing fan configured to blow outdoor air into a room, an indoor unit that discharges air heat-exchanged with the refrigerant flowing-in from the outdoor unit to the room, and a connection piping that connects the outdoor unit and the indoor unit. Here, a plurality of protrusions may be formed at least one side of the blowing fan, and a convex portion and a concave portion may be formed on a surface of the blowing fan so that the surface of the blowing fan is indented.

Abstract: Provided is a propeller fan including a hub having an oval shape in an axial direction, a plurality of wings that extend from the hub, and at least one reinforcement rib that extends from the hub and is formed closer to a leading edge of each of the plurality of wings. Through this configuration, the propeller fan has blowing efficiency and stiffness, and the weight and material cost of the propeller fan can be reduced.