Ventilation can be provided by:


• Spokes:
These are spokes welded in the bore hole of the commutator. With larger commutators, spokes are provided in the front at the brush track and in the back at the riser,so the middle remains free of load.
• Ventilation holes between the bolts
• Ventilations holes in the bore hole:
Ventilation holes are often drilled in smaller commutators.
• Spoke wheel:
When necessary, an inner wheel is welded on the underside of the spokes.