What is the composition and working principle of the ignition system?
1 Answers
Ignition system components: power source (battery or generator), ignition coil, distributor, spark plug, ignition switch, and control circuit. Principle: During engine operation, the breaker contacts continuously open and close. When the breaker contacts are closed, the current from the battery flows from the positive terminal of the battery, through the ignition switch, the primary winding of the ignition coil, etc., and back to the negative terminal of the battery. More details are as follows: 1. The automotive ignition system is designed to provide the spark plugs with a high-energy high-voltage current (approximately 15,000 to 30,000 volts) in the correct firing order for each cylinder, ensuring a strong enough spark to ignite the air-fuel mixture. 2. Working principle: When the ignition switch is turned on, the engine starts running. During operation, the breaker cam continuously rotates, causing the breaker contacts to open and close repeatedly. When the contacts are closed, the battery current flows from the positive terminal, through the ignition switch, the primary winding of the ignition coil, the breaker arm, contacts, and the distributor housing ground, returning to the negative terminal of the battery. 3. When the breaker contacts are pushed open by the cam, the primary circuit is interrupted, causing the current in the primary winding of the ignition coil to drop rapidly to zero. The magnetic field around the coil and within the iron core also decays quickly and disappears, inducing a voltage in the secondary winding of the ignition coil, known as the secondary voltage. The current flowing through this circuit is called the secondary current, and the circuit itself is referred to as the secondary circuit.
