Dual-face cooling fan for a dynamoelectric machine

Claim 1

A dynamoelectric machine comprising: (a) a housing having ventilated first and second end frames, wherein the second end frame includes a cylindrical portion having a plurality of circumferential vents; (b) fastener means for removably connecting the first and second end frames; (c) a stator assembly and a rotor assembly mounted in a chamber formed by the first end frame, the rotor assembly including a rotatable shaft extending into a chamber formed by the second end frame; (d) heat-generating means mounted in the chamber formed by the second end frame; (e) a dual-face cooling fan assembly having a sleeve portion mounted on the shaft in the chamber formed by the second end frame so that the fan assembly is mounted between the stator and rotor assemblies and the heat-generating means and adjacent the cylindrical portion of the second end frame, the fan assembly including (i) a divider disk mounted on the sleeve portion having a diameter slightly less than the inner diameter of the cylindrical portion, and (ii) a plurality of blades provided on each surface of the disk wherein the blades extend to a diameter slightly less than the inner diameter of the cylindrical portion; whereby as the fan assembly rotates with the shaft, a plurality of separate air currents are drawn axially through the housing from opposite end frames into the divider disk and then radially expelled from the housing through the circumferential vents without substantial mixing of the air currents.