Air-cooled rotor for electric motor

In combination with a rotor having:

• a ferrous core extending along and centered on an axis and formed with axial slots;
• a winding extending along the slots of the core and having opposite axial ends extending axially beyond the core;
• and
• means for circulating air axially over the core and winding;
• the improvement comprising:
• a plurality of ribs fixed to the rotor and winding and each extending at least generally axially and radially over at least one of the ends of the winding so as to project generally axially from the one end, the ribs being spaced apart on the one end such that the winding is exposed between the ribs, wherein the ribs are part of a cage having an inner ring and an outer ring and the ribs extend between the rings and wherein the ribs are spaced angularly irregularly and define with the rings openings of different sizes through which the one winding ends is exposed.

In an electric motor comprising:

• a ferrous core extending along, rotatable about, and centered on an axis, the core being formed with axial slots and having opposite end edges centered on the axis;
• a winding extending along the slots of the core and having opposite axial ends extending axially beyond the core;
• fan means for circulating air axially over the core and winding;
• respective cages on the winding ends and each including
• an inner ring,
• an outer ring fitted over the respective end edge of the core, and
• a plurality of ribs extending axially and radially between the rings and projecting generally axially from the respective winding end, the ribs being spaced apart on the respective winding end such that the winding is exposed between the ribs, whereby on rotation of the rotor particles blown by the fan means are deflected by the ribs before they engage the winding ends.