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Spark Ignition Engine, Working and Parts

What is Spark Ignition Engine:

Spark Ignition Engine: Spark Ignition Engine is known as SI Engine and it is a type of internal combustion engine where fuel in the combustion chamber is used to burn with the help of spark produced by the spark plug. A high voltage current is used to produce a spark in the plug and this spark plug is used to connect with the top of the combustion chamber to ignite the fuel and develops the heat which is further converted into the mechanical energy.Spark plug engines are the petrol engines, due to the less compression ratio a spark is used to burn the fuel.Spark produced in the plug used to ignite the fuel in the combustion chamber at the time of ignition or power stroke and produce the energy.

Main Parts of spark Ignition Engine:

The Following are the main parts of Spark Ignition Engine
  • Cylinder
  • Piston
  • Piston Rod
  • Connecting Rod
  • Spark Plug
  • Valves
The cylinder is used to run the complete process in it like compression, combustion, exhaustion etc. cylinder head consists of different parts like inlet, outlet valves and spark plug.

This is used to compress the fuel in the combustion  chamber and produce the energy.

Piston rod:
This is used to connect with the crankshaft to slide inside the cylinder.

Connecting rod:
This used to connect the piston rod and crankshaft, which plays an important role in converting the reciprocating motion into circular motion.

Spark plug:
This is used to produce the spark and ignites the fuel in the combustion chamber to produce heat.

Valves are used to allow the fuel into the combustion chamber by the inlet valve and escape the hot gases from the outlet valve.

Working of Spark Ignition Engine:

The fuel from the carburetor used to enter into the combustion chamber at the time of suction stroke by moving the piston downwards by opening the inlet valve and this fuel gets compressed by moving the piston upwards when the piston moves maximum to the top of the cylinder the spark plug produces a spark to ignite the fuel and generates huge power and this power is used to store in the flywheel and reused when it is required and at the time of compression and ignition both the inlet and outlet valves gets closed, after the ignition process the burned fuel develops hot waste gases and this waste gas passes out at the time of exhaust stroke by opening the outlet valve.



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