Coreless DC Motor Technology

Coreless DC motors differ from traditional DC motors in significant ways. The most obvious and important difference is the rotor winding.

Instead of coils wound around a stack of iron laminations, the coil is formed as a thin hollow cylinder (item 1 above).
The stator with its permanent magnets (item 2) supplies the magnetic field flux and fits in the hollow center of the winding. It’s rigidly affixed to the outside motor housing (item 6), which completes the magnetic circuit. The rotor is

supported by bearings (items 5) and rotates around the magnetic core.

Coreless DC motors are usually small in size, ranging from 6 mm (0.24") to less than 75 mm (3") in diameter.Continuous power is normally limited to 250 Watts or less.

They are a preferred choice for many medical devices, small pumps, and document handling/dispensing equipment.