BATTERY/COIL IGNITION SYSTEM: PARTS AND WORKING PRINCIPLE.

This is a type of ignition system where the battery is the source of electrical energy.

Parts of the coil Ignition System

1. Battery

2. Ammeter

3. Ignition switch

4. Ignition Coil ( primary winding, secondary winding & soft iron core.)

5. Distributor

6. Distributor cap

7. Metallic electrodes

8. Rotor

9. Contact breaker points ( movable point & fixed point.)

10. Condenser/ Capacitor

11. Cam

12. Heel

13. Fork

14. High tension leads

15. Spark plugs ( center electrode & earth electrodes.)

OPERATION

When the ignition key is turned on, a low voltage current (12 volts)flows through the primary winding ,which has fewer turns.A secondary winding is wounded inside the primary winding and has several turns. one end of secondary winding is connected to the primary winding and the other end is connected to high tension cable to the distributor. A primary winding cable is further connected from the coil to the contact breaker points where the primary current flows through the contact breaker then to earth to complete the circuit. The cam which is being driven by the engine through a cam shaft,operates the opening and closing of the conduct breaker points.If the contact breaker points are in contact, both the fixed and movable contact , the current flows through then back to earth on the chassis of the vehicle and the primary circuit is completed.this action will build up a magnetic field around the soft iron core. If the two contact breaker points are opened by the action of the cam's rotation ,the magnetic field created in the primary winding collapse and the lines of magnetic field cuts through the secondary winding inducing a high voltage of 1800v up to around 20,000V. This high voltage is then carried to the distributor cap by high tension leads and then distributed to the spark plugs by the rotor. As the rotor rotates, it touches the metallic electrodes(distributor segments)one at a time. The metallic electrode has high-tension leads that transfer the high voltage to the spark plugs according to the firing order hence inducing sparks.