Patent ID: 6755615
Filing Date: 2004-06-29
Classification: F04D,F05D

Abstract:
A centrifugal impeller mounted to rotate on an axis, the impeller comprising a plurality of blades, each having a leading edge and a trailing edge, an impeller hub, and a top shroud; the blades defining an impeller diameter, a cylindrical area ratio, a minimum chord length, a blade meanline length and a blade solidity; and the top shroud forming an inlet to the impeller having an impeller inlet radius; said impeller characterized in that:a) it is injection molded in one piece; b) the impeller hub extends outwardly to a radius less than that of the impeller inlet radius; c) the blades extend outwardly from a radius less than the impeller hub radius; d) the top shroud has curvature in a plane that contains the impeller axis; e) the cylindrical area ratio is between 1.0 and 2.0; and f) said minimum chord length is at least 15% of the impeller diameter.