Commutator

Technology / Motors / Commutator: A cylindrical device mounted on the armature shaft and consisting of a number of wedge-shaped copper segments arranged around the shaft (insulated from it and each other. The motor brushes ride on the periphery of the commutator and electrically connect and switch the armature coils to the power source.
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Brush

Technology / Motors / Brush: A piece of current conducting material (usually carbon or graphite) which rides directly on the commutator of a commutated motor and conducts current from the power supply to the armature windings. MORE

Front End Of A Motor

Technology / Motors / Front End Of A Motor: The front end of a normal motor is the end opposite the coupling or driving pulley. (NEMA) This is sometimes called the opposite pulley end (O.P.E.) or commutator end (C.E.). MORE