| 摘要 |
<p>2065445 9104419 PCTABS00003 A clutch fan (20) has a new and unique blade design that results in quieter and more efficient operation. The blade design involves the leading edge (30) having inner (34), intermediate (36), and outer regions (38) such that the intermediate region (36) is of increasing skew in the direction of rotation and the outer region (38) is of decreasing skew. The pitch ratio increases as a function of increasing blade radius. Along the outer region (38), the blade (22) increases in pitch on a defined curvature as a function of blade radius and angle to form a tip curl.</p> |
