Patent ID: 6287078
Filing Date: 2001-09-11
Classification: F04D,Y10S

Abstract:
An axial flow fan, comprising a hub, a plurality of blades extending radially outwardly from the hub, and an outer band surrounding peripheral ends of the blades, wherein a median sweep angle of each blade increases gradually from 0.degree. along the outward radial direction, a leading sweep angle of each blade starts from an angle of less than 0.degree., increases gradually and terminates at an angle of more than 40.degree., a trailing sweep angle of each blade increases along the outward radial direction after it decreases from an angle of more than 0.degree. along the outward radial direction, a chord length of each blade gradually increases along the outward radial direction, and a pitch angle of each blade gradually decreases along the outward radial direction.