Abstract: In a dynamoelectric machine, a fan diffuser and collector combination is part of the cooling system of the machine. The fan diffuser and collector is located in the annular chamber defined by the inner and outer end plate shields at one end of the machine. The fan diffuser includes a disk disposed in the radially inner portion of the annular chamber. An inboard surface of the disk is parallel to the adjacent surface of one of the shields. Both surfaces define a diffuser channel which receives substantially all of the gas flow expelled by a fan radially coextensive with the annular chamber. The disk is mounted on the other shield but has an outboard surface spaced away from that latter shield. The disk is foreshortened with respect to a frame wrapper which surrounds the stator and rotor of the dynamoelectric machine thereby forming a collector.