External Cage AC Induction motor
Small AC fans often fall into that category.



It's cast as a bell shaped rotor, but you can see the skewed bars of the "cage", apparently formed by aluminium flowing into slits in the laminations during the casting process. These laminations contain the magnetic field quite well, but I can't put a figure on how close it is to the traditional internal rotor.

The "shaded pole" structure is not so clearly visible in the wound stator, hidden in the green resin (but you can see a longer pole, and a slit by the shorter one)