A DC motor contains a coil of wire, known as an armature, that is placed within a magnetic field. When an electrical current is passed through the armature, it creates an electromagnetic field that interacts with the magnetic field, causing the armature to rotate. This rotation is what converts electrical energy into mechanical energy.
The commutator is a critical component of a DC motor. Its main function is to reverse the direction of the current flowing through the armature at the appropriate time. This allows for continuous rotation of the motor in a single direction.
The speed of a DC motor is directly proportional to the voltage applied. This means that as the voltage increases, the speed of the motor also increases, and vice versa. This relationship is known as the motor's speed-torque characteristic.
A brushed DC motor uses a physical contact, or brush, to deliver power to the armature, while a brushless DC motor uses electronic commutation. Brushless motors are typically more efficient, have longer lifetimes, and require less maintenance compared to brushed motors.
The number of coils in the armature directly impacts the torque and speed capabilities of a DC motor. Generally, a motor with more coils will have a higher torque output, while a motor with fewer coils will have a higher speed output. However, the design and construction of the motor also play a significant role in its overall performance.