AXIAL FLOW FAN

摘要

PURPOSE: An axial flow fan is provided to elevate blowing efficiency and to buffer noise by maintaining mutual complementary relation of respective design elements of an axial flow fan such as sweeping angle of a fan, curvature of a leading edge and a trailing edge and setting angle of a chord. CONSTITUTION: A high efficiency and low noise axial flow fan is composed of a hub(1), many blades(2) extended in radial on the circumference of the hub and a circular band(3) connecting outer ends of the blades. The sweeping angle of the median line(6) of the blades gradually increased from zero in the rotational direction of the blades as going to the outer end(OM) from the inner end(IM). The sweeping angle of the leading edge line(4) of the blades gradually increases from the angular degree below zero as going to the outer end(OL) from the inner end(IL) after slightly decreasing and has at least 40 degrees of angular degree at the outer end. The sweeping angle of the trailing edge line(5) of the blades gradually increases as going to the outer end(OT) from the inner end(IT) by starting from plus angular degrees after decreasing The radial width of the blades increases as going to the outer end. The setting angle is gradually decreases as coming to the outer end.