Abstract: An electric machine includes a housing, an end shield, a stator, and a rotor assembly. The end shield can define at least one pin, and the stator can define at least one track. The stator can be positioned on the end shield such that the pin is received within the track. The stator can be captured between the end shield and a stop within the housing. The rotor assembly can include an adaptor sleeve and/or a bearing with a plurality of steel rolling elements. End caps can be coupled to the stator, and power and control electronics can be integrated within the housing.

Abstract: A rotor assembly for an electric machine includes a rotatable shaft, a rotor core coupled to the shaft for common rotation, and an impeller coupled to the shaft for common rotation. A bearing is coupled to the shaft generally between the rotor core and the impeller. The bearing can include an outer race sized smaller than an opening defined by the machine housing. The bearing can include steel rolling elements such as steel balls or generally cylindrical steel rollers. An adaptor sleeve can be disposed generally around the outer race. The adaptor sleeve can be disposed within the opening defined by the housing for securing the adaptor sleeve and the bearing within the opening defined by the housing.