US Patent 9816521 Propeller fan, fluid feeder, and molding die

A blade of a propeller fan includes a blade root portion, a front edge portion, a blade tip end portion, a rear edge portion, a blade rear edge portion, and an outer edge portion. A blade surface of the blade has an inner region including the blade root portion, an outer region including the blade rear end portion, and a coupling portion extending from a front end portion located close to the blade tip end portion to a rear end portion located close to the rear edge portion and coupling the inner region and the outer region to each other such that a side of a positive pressure surface of the blade surface is projecting and a side of a negative pressure surface of the blade surface is recessed.