Axial flow fan

The utility model relates to an axial flow fan which comprises a fan frame, the fan frame is provided with a cylindrical shell, a mounting seat is supported in the shell through spokes, a mounting hole is formed in the mounting seat, the mounting hole is a non-circular hole, the side wall of the mounting hole is matched with a fastener penetrating through the side wall, and the inner extending end of the fastener extends into the mounting hole; one end of the middle pipe is provided with a mounting part, the mounting part is in profile modeling with the mounting hole and is contained in the mounting hole, the inward extending end of the fastener is connected to the side wall of the mounting part, a stator assembly is supported on the middle pipe, a rotatable axial flow fan impeller is supported on the middle pipe, and a rotor assembly corresponding to the stator assembly is arranged on the axial flow fan impeller. The axial flow fan is simple in traditional structure and convenient to machine, the fan frame a