Patent ID: 6672839
Filing Date: 2004-01-06
Classification: F04D

Abstract:
A fan wheel comprising:a center section; and blades extending from the center section, each blade comprising a first section proximate a blade tip, a second section, a leading edge along the first and second sections, a trailing edge along the first and second sections, the blade tip being formed at a junction of the leading and trailing edges, wherein the first section is curved at the trailing edge with a first angle relative to a tangent to the first section at the trailing edge of between about 7Â°-13Â°, wherein the second section is curved at the trailing edge with a second angle relative to a tangent to the second section at the trailing edge of between about 33Â°-39Â°, said second section being curved upwardly from the leading edge to the trailing edge, said second section having a substantially inverted cup-like shape.