Ignition system 3&4.pdf for the mechanical engineering

Ignition system

1. IGNITION SYSTEM

2. DEFINITION :
•THIS SYSTEM IS A PART OF THE ELECTRICAL SYSTEM
WHICH CARRIES THE ELECTRIC CURRENT TO THE SPARK
PLUG WHERE THE SPARK NECESSARY TO IGNITE THE FLUE
AIR MIXTURE IN THE COMBUSTION CHAMBER IS PRODUCED.
•THIS SYSTEM SUPPLIES HIGH VOLTAGE OF CURRENT (AS
MUCH AS 20000VOLTS) TO PRODUCE SPARK AT THE SPARK
PLUG.

3. TYPES OFIGNITIONSYSTEM:
•ELECTRONIC IGNITION SYSTEM ,
•TRANSISTORISED IGNITION SYSTEM,
•MAGNETO IGNITION SYSTEM, AND
•BATTERY IGNITION SYSTEM.

4. •ELECTRONIC IGNITIONSYSTEM:
•AN ELECTRONIC IGNITION SYSTEM IS A TYPE OF
IGNITION SYSTEM IN INTERNAL COMBUSTION ENGINES
THAT USES ELECTRONIC COMPONENTS,TO GENERATE
AND CONTROL THE TIMING OF THE SPARK NEEDED TO
IGNITE THE AIR-FUEL MIXTURE IN THE ENGINE
CYLINDERS. THIS SYSTEM IMPROVES ENGINE
PERFORMANCE, AND FUEL EFFICIENCY, COMPARED TO
TRADITIONAL MECHANICAL IGNITION SYSTEMS.

5. COMPONENTS :
1.IGNITION SWITCH ,
2.BATTERY,
3.ELECTRONIC CONTROL UNIT,
4.IGNITION COIL ,
5.CRANKSHAFT POSITION SENSOR,
6.IGNITION MODULE,
7.SPARK PLUGS,
8.DISTRIBUTOR .

6. DIAGRAM:

7. CONSTRUCTION AND WORKING PRINCIPLE’S:
•SENSOR MANUFACTURING: THIS INVOLVES PRECISE MANUFACTURING
TECHNIQUES DEPENDING ON THE SENSOR TYPE (E.G., WINDING COILS
FOR MAGNETIC PICKUPS, SEMICONDUCTOR FABRICATION FOR HALL
EFFECT SENSORS).
•ECU/PCM MANUFACTURING: THIS IS A COMPLEX PROCESS INVOLVING
THE FABRICATION OF MICROPROCESSORS, MEMORY CHIPS, AND OTHER
ELECTRONIC COMPONENTS, FOLLOWED BY ASSEMBLY ONTO PRINTED
CIRCUIT BOARDS AND ENCAPSULATION FOR PROTECTION.
•SPARK PLUG MANUFACTURING: THIS INVOLVES FORMING THE METAL
SHELL, INSULATOR (TYPICALLY CERAMIC), AND ELECTRODES, AND THEN
PRECISELY SETTING THE SPARK PLUG GAP.

9. •IGNITION COIL MANUFACTURING: THIS INVOLVES WINDING COILS OF
WIRE AROUND A MAGNETIC CORE, INSULATING THE WINDINGS, AND
ENCLOSING THE ASSEMBLY IN A DURABLE HOUSING. FOR COP
SYSTEMS, THE DESIGN INTEGRATES THE COIL DIRECTLY WITH A
BOOT THAT FITS OVER THE SPARK PLUG.
•WIRING HARNESS ASSEMBLY: THIS INVOLVES CUTTING WIRES TO
SPECIFIC LENGTHS, CRIMPING TERMINALS ONTO THE ENDS, AND
ASSEMBLING THEM INTO A HARNESS WITH PROTECTIVE SHEATHING
AND CONNECTORS.
•IN SYSTEMS WITH A DISTRIBUTOR, THE DISTRIBUTOR ROTOR,
CONTROLLED BY THE ENGINE’S CAMSHAFT, PHYSICALLY ROUTES
THE HIGH-VOLTAGE PULSE TO THE CORRECT SPARK PLUG WIRE AT
THE RIGHT TIME IN THE ENGINE’S FIRING ORDER.

10. ADVANTAGE’S :
1.REDUCED MAINTENANCE,
2.INCREASED RELIABILITY,
3.IMPROVE SPARK TIMING ACCURACY,
4.POWERFUL SPARK,
5.LOWER EMISSION.

11. DISADVANTAGE’S :
1.HIGHER INITIAL COST ,
2.COMPLEXITY ,
3.SENSITIVE TO VOLTAGE FLUCTUATION ,
4.DIFFICULT TO REPAIR ,
5.DEPENDENCE ON ELECTRONIC SENSOR.

12. TRANSISTORISED IGNITION SYSTEM:(TIS)
•A TRANSISTORISED IGNITION SYSTEM IS AN IGNITION SYSTEM IN
WHICH A TRANSISTOR IS USED AS A SWITCH TO CONTROL THE
PRIMARY CURRENT IN THE IGNITION COIL, RESULTING IN MORE
ACCURATE SPARK TIMING, REDUCED WEAR, AND IMPROVED ENGINE
PERFORMANCE.
•A TRANSISTORISED IGNITION SYSTEM (TIS) IS AN ADVANCED TYPE
OF ELECTRONIC IGNITION SYSTEM USED IN MODERN VEHICLES TO
GENERATE THE HIGH -VOLTAGE SPARK NEEDED TO IGNITE THE FUEL -
AIR MIXTURE IN THE ENGINE’S CYLINDERS.

13. COMPONENTS :
1.BATTERY
2.IGNITION SWITCH
3.IGNITION COIL
4.PULSE GENERATOR/TRIGGERING DEVICE,
5.CONTROL UNIT (ELECTRONIC CONTROL MODULE -ECM),
6.TRANSISTOR,
7.SPARK PLUG,
8.DISTRIBUTOR

14. DIAGRAM:

15. CONSTRUCTION :
1.BATTERY: PROVIDES POWER (TYPICALLY 12V DC) TO THE SYSTEM.
2. IGNITION SWITCH :TURNS THE IGNITION SYSTEM ON OR OFF.
3. PULSE GENERATOR (PICKUP COIL) : A MAGNETIC OR HALL -EFFECT
SENSOR THAT DETECTS THE ENGINE’S POSITION AND SPEED BY
SENSING THE ROTATION OF THE DISTRIBUTOR OR CRANKSHAFT.
4. ELECTRONIC CONTROL UNIT (ECU) / IGNITION CONTROL MODULE
(ICM):
CONTAINS TRANSISTORS AND OTHER CIRCUITRY TO PROCESS
SIGNALS FROM THE PULSE GENERATOR.

16. 5. POWER TRANSISTOR (IN THE ECU/ICM) : ACTS AS A FAST
ELECTRONIC SWITCH. CONTROLS THE PRIMARY CURRENT FLOW IN
THE IGNITION COIL.
6. IGNITION COIL :STEPS UP THE 12V BATTERY VOLTAGE TO HIGH
VOLTAGE (20,000V –40,000V) NEEDED TO FIRE THE SPARK PLUGS. HAS
PRIMARY AND SECONDARY WINDINGS.
7. DISTRIBUTOR (IN OLDER SYSTEMS) :DIRECTS HIGH VOLTAGE TO THE
CORRECT SPARK PLUG. MODERN SYSTEMS MAY USE COIL -ON-PLUG
SYSTEMS, ELIMINATING THE DISTRIBUTOR.
8. SPARK PLUGS : IGNITE THE AIR -FUEL MIXTURE IN THE COMBUSTION
CHAMBER.

17. WORKING PRINCIPLE:
•WHEN THE ENGINE TURNS, THE PULSE GENERATOR SENDS SIGNALS
TO THE ECU/ICM.
•THE ECU USES A POWER TRANSISTOR TO SWITCH THE IGNITION COIL
ON AND OFF RAPIDLY.
•WHEN THE COIL’S MAGNETIC FIELD COLLAPSES, A HIGH -VOLTAGE
PULSE IS SENT TO THE SPARK PLUG.
•THIS CAUSES A SPARK THAT IGNITES THE FUEL -AIR MIXTURE IN THE
ENGINE.

18. ADVANTAGE’S :
•IMPROVE SPARK TIMING ACCURACY.
•HIGHER VOLTAGE AND STRONGER SPARK.
•REDUCED REAR AND MAINTENANCE.
•BETTER FUEL EFFICIENCY.
•RELIABLE COLD STARTING.

19. DISADVANTAGE’S :
•HIGHER INITIAL COST.
•COMPLEX ELECTRONIC COMPONENTS.
•ELECTRONIC MODULES CAN FAIL TO EXCESSIVE HEAT AND
WATER.
•DIFFICULTY TO REPAIR.
•DEPENDENCE ON BATTERY VOLTAGE.

20. APPLICATION OF IGNITION SYSTEM:
1.AUTO MOBILE (CAR, BUS )
2.COMMERCIAL VEHICLE’S.
3.MARINE ENGINES .
4.SMALL ENGINES.
5.AIRCRAFT PISTON ENGINES .
6.AGRICULTURAL PURPOSES .