How Magneto Ignition System works

Ignition system is a group of components which deliver the spark to the spark plug to ignite the air fuel mixture.

Mainly we have three types of ignition system:-

1. Battery Ignition System
2. Magneto Ignition System
3. Electronic Ignition system

2. Magneto Ignition System

Name of the ignition system itself indicate that in this system magnet is used . when magnet is run by the engine it produces current and supplies to the primary winding .system having set of winding namely primary winding and secondary winding.Battery and ignition coil of the battery have been replaced by the compact magneto. low current voltage is converted into high current voltage by disturbing the path of the current which is enough to spark and fire the air fuel mixture.
Components of Magneto Ignition System are- Magneto,breaker points,condenser ,ignition switch, distributor,spark plug

Magneto Ignition system is classified into two types :-

1. Rotating Armature Types

Rotating armature is consist of two coils, one is primary coil,one secondary coil and condenser. primary coil having few hundred winding of wire where as secondary coil having some few thousand turns winding of wire .Contact breaker and condenser is attached to the armature which  rotates between the pole of permanent magnet .

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• when the armature rotates in between the magneto ,magnetic flux in the core reaches zero to maximum.
• As the magnetic flux alternatively increase and decrease, the voltage is induced in the primary coil and secondary coil.
• As we can see in the fig. when the breaker points are closed ,current flow in the primary circuit. breaker points are actuated by the cam which is attached to the rotor of the follower.
• By means of the breaker points ,an increase in the rate of the magnetic flux break down is produced 
• Rapid discharge of the condenser produce an instantaneous break down of the magnetic flux .
• A rapid break down induces very high voltage 10k to 20k volts in the secondary circuit
• This high voltage is distributed by distributor to spark plug according to the firing order of the engine and hence spark plug ignite the mixture in the combustion chamber.
• Engine can be stopped by closing the ignition switch and grounding the primary circuit.

 2.Rotating Magneto Type

working principle of this system same as that of the rotating armature system.Here the magnet itself rotate to produce the require current to produce the spark.

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Also read Ignition System and Battery Ignition System

Need of Lubrication System in Engine and its Function.