Working Principle of an Ignitor (Igniter)

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An ignitor (or igniter) is a device used to initiate combustion by producing a spark or heat. It is commonly used in:

Internal combustion engines (petrol/gas)

Gas stoves and burners

Gas geysers

Jet engines

Industrial furnaces

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⚙️ General Working Principle:

1. Power Supply:

The ignitor receives electrical power from a battery, AC mains, or ignition coil (in engines).

2. Energy Conversion:

The electric energy is either:

Converted into a spark (high voltage arc) — like in spark plugs.

Converted into heat — like in hot surface ignitors or glow plugs.

3. Ignition of Fuel:

The spark or heat ignites the air-fuel mixture (in engines) or gas (in burners/stoves).

This starts the combustion process.

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🔧 Types of Ignitors and Their Working:

Type Working

Spark Ignitor (e.g. spark plug) Generates high-voltage spark (10,000–40,000 volts) across a gap to ignite fuel-air mix.

Hot Surface Ignitor A ceramic element heats up (to ~1,200°C) when current passes, igniting gas. Used in furnaces.

Piezoelectric Ignitor Pressing a button creates mechanical force on a piezo crystal → voltage spark. Common in gas lighters.

Glow Plug (in diesel engines) Heats up using resistance heating to help ignite diesel fuel during cold starts.

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🔁 Cycle in Petrol Engine (Using Spark Ignitor):

1. Ignition coil steps up battery voltage.

2. High voltage goes to spark plug.

3. Spark jumps across plug gap.

4. Air-fuel mixture ignites.

5. Power stroke begins.

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