The working principle of the starter mainly includes the following steps:
1、 Start signal input
When the driver turns the key to the start position or presses the start button, the car's electrical system will receive a start signal. This signal will trigger a series of circuit actions to prepare for the operation of the starter motor.
2、 Electromagnetic switch action
The electromagnetic switch of the starter motor generates a magnetic field by energizing the coil after receiving the start signal. This magnetic field attracts the iron core to move, thereby driving the fork action.
The fork pushes the driving gear of the starter to mesh with the ring gear on the engine flywheel. This step ensures that the starter can transmit power to the engine.
3、 Motor starting rotation
When the driving gear fully meshes with the flywheel ring gear, the main contact of the electromagnetic switch closes, and the electrical energy from the battery is directly transmitted to the motor part of the starter.
The starter motor is usually a DC motor, and after being powered on, the armature begins to rotate under the action of electromagnetic force in the magnetic field.
The rotation of the armature is transmitted to the driving gear through a transmission mechanism (such as a one-way clutch), and the driving gear drives the engine flywheel to rotate.
4、 Engine start
The engine flywheel gradually increases in speed under the drive of the starter. When the engine speed reaches a certain level, the combustion cycle of the engine itself begins to work and can independently maintain operation.
At this point, the driver releases the key or start button, the start signal stops, the starter electromagnetic switch coil loses power, and the iron core returns under the action of the spring.
The shift fork will drive the gear back to its original position from the flywheel ring gear, and the starter will stop working.
5、 The function of one-way clutch
During the operation of the starter motor, the one-way clutch plays an important role. It allows the starter to transmit power to the flywheel when starting the engine, and when the engine speed is higher than the starter after starting, the one-way clutch can automatically slip, preventing the engine's power from being transmitted in reverse to the starter, thereby protecting the starter from damage.
