2. Need of ignition system
Ignition system provides high voltage
spark in the combustion chamber at the
correct time.
Distributed high voltage spark to each
spark plug in correct sequence .
Provides a method of turning a spark
ignition engine on & off
3. Introduction
Ignition system is part of electric system
which carries the electric current to the
spark plug where the spark is necessary
to ignite the air-fuel mixture.
Produces high voltage arcs at the spark
plug electrode.
These high voltage produce by ignition
coil, which is supplied with lower voltage
battery.
4. The combination of all the devices
required to produce an electric spark of
desired intensity and at proper moment is
called spark ignition system
The spark must occurs towards the end of
compression stroke
Automotive engines are usually cranked
by a small electric motor, which is better
known as a starter motor, or simply a
starter. The starter motor for SI and CI
engines operates on the same principle as
a direct current electric motor.
5. Requirements of an ignition
system
It should provide a good spark between
the electrodes of the plugs at the correct
timing
The duration of the spark must be long
enough with sufficient energy to ensure
that ignition of the mixture has a high
chance of occurring
6. The system must distribute this high
voltage to each of the spark plugs at
the exact time in every cycle, i.e., it
must have in it a distributing device
It should function efficiently over the
entire range of engine speed
It should be light, effective and reliable
in service
7. TYPES OF IGNITION SYSTEM
BATTERY IGNITION SYSTEM
MAGNETO IGNITION SYSTEM
ELECTRONIC IGNITION SYSTEM
LASER IGNITION SYSTEM
8. BATTERY IGNITION PARTS
BATTERY provides power for system
IGNITION SWITCH allows driver to turn
ignition on and off
IGNITION COIL changes battery voltage
to 30,000V during
normal operation and has a potential to
produce up to 60,000V
SWITCHING DEVICE mechanical or
electronic switch that operates
Ignition coil(Pick-up coil, Crank sensor, Cam sensor
9. SPARK PLUG uses high voltage from
ignition coil to produce an arc
in the combustion chamber.
IGNITION SYSTEM WIRES connect
components
• Distributor It causes the spark to occur at
each plug earlier in the compression
stroke as engine speed increases, and
vice versa.
10.
11. WORKING
The secondary circuit converts
magnetic induction into high voltage
electricity to jump across the spark
plug gap, firing the mixture at the right
time. The functions of the components
are:
12. Secondary coil
the part of the coil that creates the high
voltage electricity
Coil wire
:a highly insulated wire to take the high
voltage to the distributor cap
Distributor cap
a plastic cap which goes on top of the
distributor, to hold the high tension
wires in the right order
13. Rotor
spins around on the top of the distributor
shaft, and distributes the spark to the right
spark plug
Spark plug leads
another highly insulated wire that takes the
high voltage from the cap to the plugs
Spark plugs
take the electricity from the wires, and give it
an air gap in the combustion chamber to
jump across, to light the mixture
