초록 ▼

A low noise axial flow fan (10/110) having a plurality of identical blades (13/113) extending from a central hub (11/111). In a preferred embodiment, each blade is highly skewed, having a backward (with respect to fan rotation direction) skew in the root portion (15/115) of the blade nearest the hub

A low noise axial flow fan (10/110) having a plurality of identical blades (13/113) extending from a central hub (11/111). In a preferred embodiment, each blade is highly skewed, having a backward (with respect to fan rotation direction) skew in the root portion (15/115) of the blade nearest the hub, changing to a highly forward skew in the portion (16/116) of the blade near the tip. The fan may be shrouded or unshrouded. In the shrouded embodiment, the fan (110) is used in conjuncton with an inlet orifice structure (131). Each blade of the fan has a chord length (Ch) that increases from root (17/117) to tip (18/118), a pitch angle (G110), both the contour of the inlet portion (126) of the shroud and the contour of the inlet portion (132) of the orifice structure are quarter sections of ellipses.

대표청구항 ▼

An axial flow fan (10) comprising; a central hub (11) and a plurality of blades (13) extending from said hub, each of said blades having a root (17), a tip (18), a root portion (15) within which the mean line (14) of said blade is swept in a first direction with respect to the direction of rotation

An axial flow fan (10) comprising; a central hub (11) and a plurality of blades (13) extending from said hub, each of said blades having a root (17), a tip (18), a root portion (15) within which the mean line (14) of said blade is swept in a first direction with respect to the direction of rotation of said fan, a tip portion (16) within which the mean line of said blade is swept in a second direction opposite to said first direction with respect to the direction of rotation of said fan, a variable pitch (Gq