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Working and construction of DC MOTOR

Today's In Industrial And technical Era, a most useful and important part is MOTOR. Whether it is a normal Drill machine or a complex Robotic Arm, Motor is used in everywhere. We just need to press ON button to start But do you know about how this thing work. Let us understand a complete structure about a DC Motor 

Usually a Electric Motor is of two type

     1) AC Motor
     2) DC Motor

In which DC MOTOR is Popular just because of some Quality like 
        a) Quick response Time
        b) Excellence Speed Controllable system 
        c) Simple Construction
        d) High RPM
        e) Low in Cost

What is Motor

The DC motor is the device which converts the direct current into the mechanical work. It works on the principle of Lorentz Law, which states that “the current-carrying conductor placed in a magnetic and electric field experience a force”. The experienced force is called the Lorentz force.
The Flemming left-hand rule gives the direction of the force.

Usually a Motor Consist of following two Components
       1) A Stator
       2) Rotor

Working and construction

1) Stator :-

As the name indicates that stator is Static in nature or The outer assembly that we see by our naked eye is Stator. Simply says that Stator is for support to Rotor. A Stator's Outer surface is known as Frame. Stator consist magnetic core winding or pole winding.

The core of pole is made up of steel and after winding it with Copper wire, It is tightened to Stator. And When current flowing through the pole winding, a stable magnetic filed is start producing by the core pole winding of Stator. Two sets of Core of different sizes facing toward each other in opposite direction are used in Stator pole.

Big Size Sets of Pole are Called Main Pole whereas smaller one are called Interpole. They are only installed in heavy duty motor where large torque is required, just to produce magnetic field.Other in simple Drone Motor, Magnets are used instead of pole winding.

2) Rotor :-

The armature coil consists the commutators and brushes. The commutators convert the AC induced in the armature into DC and the brushes transfer the current from rotating part of the motor to the stationary external load. The armature is placed between the north and south pole of the permanent or electromagnet.

When DC current flow through the armature coil, a magnetic filed is produced by the current around the coil

By the interaction of the fields (produced by the coil and the magnet), the resultant field develops across the conductor. The field exerts the force at the ends of the conductor, and thus the coil starts rotating.

The actual DC motor consists of a large number of armature coils. The speed of the motor is directly proportional to the number of coils used in the motor. These coils are kept under the impact of the magnetic field.

The one end of the conductors is kept under the influence of the north pole, and the other end is kept under the influence of the south pole. The current enters into the armature coil through the north pole and move outwards through the south pole.

When the coil moves from one brush to another, at the same time the polarity of the coil also changes. Thus, the direction of the force or torque acting on the coil remains the same.

The torque induces in the coil become zero when the armature coil is perpendicular to the main field. The zero torque means the motor stops rotating. For solving this problem, the number of armature coil is used in the rotor. So, if one of their coils is perpendicular to the field, then the other coils induce the torque. And the rotor moves continuously.

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