Abstract: Fans according to some embodiments of the present invention include a spider, a central hub coupled to the spider, and two or more fan blades. One or more fan design features can be employed (alone or in combination) in the fans of the present invention, including the use of spider arms and/or fan blades having twisted shapes, spider lobes having cupped shapes, spiders and/or fan blades having thinner dimensions than conventional spider and fan blades in similarly-sized fans, fan blades having narrower widths, larger camber-to-chord ratios and/or tapering camber-to-chord ratios, and embossments located on the spider or the fan blades of the fan. In addition, pre-balanced spider assemblies can be employed as an alternative to balancing a fan after assembly.

Abstract: The present invention employs improved fan blade shapes to improve fan blade performance in one or more manners (i.e., increased fan efficiency, lower fan noise, greater fluid moving capability, and the like). In some embodiments, the fan blade has a front side, a rear side, an inner attachment portion, an outer edge, a curved leading edge and a curved trailing edge. The outer edge can define an arc between a forward position and a rearward position of the fan blade. In some embodiments, the leading edge extends outward and intercepts the arc of the outer edge at the forward position, and the trailing edge extends outward to the rearward position. Various angles, lengths, and other dimensions of the blade can have selected values to produce superior fan performance.