Starters are also called electric motors. It converts the electrical energy of the battery into mechanical energy and drives the flywheel of the engine to start the engine.
The motor consists of a magnetic field
(stator), armature (rotor) and commutator. In order to increase the
torque, a multi-pole magnetic field is used. There are usually 4
magnetic fields. When current passes through the armature coil, the
entire coil will rotate with torque. Since the DC motor generates a
certain back electromotive force after being energized, it is
proportional to the engine speed and inversely proportional to the
torque, so it can meet the requirements of engine start. The starting
current of the starter is large, so the starting time must be short
during operation.