List the main parts of D.C. motor

1 Answer

Answer :

Main parts of D.C. motor and their functions: 

Part
Functions
Yoke
i) Provides mechanical support for poles. ii) Acts as protecting cover for machine. iii) Carries magnetic flux.
Pole Core & Pole Shoes
i) Provides support for the field winding, which is placed around it. ii) Allows the field winding to produce magnetic flux in it. iii) Pole shoes spread out the magnetic flux over the armature periphery more uniformly. 
Field Winding 
Produces mmf and consequently magnetic flux when carries current. 
Armature
i) It houses the armature conductors. ii) It provides rotation of armature conductors in the magnetic field. 
Armature Winding 
Provides conductors to - induce emf in it (in generator) - produce force on it (in motor) 
Commutator
i) Works as media to collect from or to send current to the armature winding. ii) Helps to maintain unidirectional current in armature winding.
Brush
i) To inject or collect current from rotating armature winding. ii) To facilitate electrical connection of rotating armature winding to external stationary circuit. 
Bearings
i) To support the rotor and reduce friction for smooth rotation of rotor. ii) Maintains rotor in a fixed physical position relative to the stator. 
Shaft
Used to transfer mechanical power 

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