PRESENTED TO- PRESENTED BY- SAURAV KUMAR VINEET KHEWAL SUSHIL PANDEY SAURABH KUMAR NISHAD SAYED HUR ABBAS NAKVI
PRESENTED TO- PRESENTED BY-SAURAV KUMARVINEET KHEWALSUSHIL PANDEYSAURABH KUMAR NISHADSAYED HUR ABBAS NAKVI
INTRODUCTION
TYPES OF SPARK IGNITION SYSTEM
BATTERY IGNTION SYSTEM
IGNITION SYSTEM PART
WORKING
MAGNETO IGNITION SYSTEM
MAGNETO IGNITION PART
WORKING
ADVANTAGES & DISADVANTAGES OF BATTERY SYSTEM
ADVANTAGE & DISADVANTAGE OF MAGNETO SYSTEM
COMPERISION BETWEEN BATTERY & MAGNETO SYSTEM
Ignition system -Turns the engine on and off
-Creates a timed spark and distributes it to the cylinders
The ignition system provides a high voltage spark in the combustion chamber at the proper time.
Distributes high voltage spark to each spark plug in correct sequence
Times the spark so it occurs as piston is nearing top dead center
Varies spark timing with load, speed, and other conditions
Ignition systems are mainly of two types;
I. Spark ignition system-
II. Compression ignition system
An ignition system obeys laws of conservation of energy. Hence it can be treated as a balance of energy between;
i. That provided by an external source
ii. That released by chemical reaction
iii. That dissipated to the surroundings as thermal energy
Two types of spark ignition systems
-Battery
-Magneto
Battery
-Battery systems transforms the battery voltage and fires the spark plug at the correct time.
Magneto
-Magneto systems must produce the current, transform the voltage and time the spark plug.
-Most small engines use the magneto system
Two types of magneto systems:
Breaker point ignition
Solid state (electronic) ignition
In this system, we use battery of 12 or 24 volts & this voltage is raised to an extremely high value of 15000 to 24000 volts for producing a spark.
Battery supplies all the electrical power to the ignition system
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).
SPARK PLUG uses high voltage from ignition coil to produce an arc in the combustion chamber.
IGNITION SYSTEM WIRES connect components.
As the key inserted to the ignition switch primary ignition circuit starts at the battery.
A low voltage is supply to the ignition coil.
The primary coil winding is not electrically to the secondary coil.
Secondary coil have work to increase the voltage supply.
This high voltage around 24000 volts goes to distributer circuit.
The distributer circuit have work to distribute the incoming voltage to the different spark plugs at suitable timing.
After that current jumps the plug gap , igniting the gasoline mixture.
In this system , battery is replaced by a generator or dynamo. This generates electricity of 6 to 12 volts, which is raised to 15000 t0 30000 volts by an ignition coil.
• Magnets
• Points (Breaker point only)
• Trigger coil
• Conductors
• Spark plug
• Condenser (Breaker point only)
• Lamination stack
• Primary winding
• Secondary winding
•As magnets in flywheel rotate past the magneto, the points close.
•The magnetic flux of the magnets the flywheel induces a current in the primary coil.• With current flowing in the
primary circuit, a magnetic field develops around the primary coil.
• This magnetic field also surrounds the secondary coil.
• As the flywheel continues to rotate the breaker points open.
When the breaker points open the magnetic field produced by the current in the primary winding collapses.
The collapsing magnetic field flows across the secondary coil which induces a current in the secondary coil.
Because there is a 60:1 ratio of windings in the two coils, the voltage is transformed to the 10,000 and 15,000 volts needed to fire the spark plug.
ADVANTAGES
•INITIAL COST OF SYSTEM IS LOW
•IT OFFERS BETTER SPARKS AT LOW SPEEDS AND AT THE STARTING OF ENGINE
•DISADVANTAGES
•AT HIGH SPEEDS ,SPARK VOLTAGE DECREASES
•BECAUSE OF BATTERY BULK OF SYSTEM IS HIGH
• ADVANTAGES
•SYSTEM IS RELIABLE AS NO BATTERY IS PRESENT
•SYSTEM IS MORE SUITABLE FOR MEDIUM AND HIGH SPEEDS
•DISADVANTAGES
•AT LOW SPEEDS AND DURING CRANKING THE VOLTAGE IS VERY LOW
•THE POWERFUL SPARKS AT HIGH SPEEDS CAUSE BURNING OF ELECTRODES