Spark plug

Bougie3

Spark-plug01

Spark_plug_gauge

Spark_plug_heat

A spark plug is a device for delivering electric current from an ignition system to the combustion chamber of a spark-ignition engine to ignite the compressed fuel-air mixture by an electric spark, while containing combustion pressure within the engine. Spark plugs have an insulated central electrode connected by a heavily insulated wire to an ignition coil or magneto outside the engine, and form a spark gap inside the cylinder.

History

The invention of the spark plug is credited to Étienne Lenoir, who developed the first internal combustion engine in the 1860s. The modern spark plug was later refined by various inventors, including Robert Bosch and Gottlob Honold.

Construction

A typical spark plug consists of a central electrode, an insulator, and a metal shell. The central electrode is usually made of a nickel alloy, while the insulator is typically made of ceramic materials. The metal shell is threaded to allow the spark plug to be screwed into the engine's cylinder head.

Operation

When the ignition system generates a high voltage, it travels through the spark plug's central electrode and jumps across the spark gap to the ground electrode. This spark ignites the fuel-air mixture in the combustion chamber, causing an explosion that drives the engine's pistons.

Types of Spark Plugs

There are several types of spark plugs, including:

• Copper spark plugs: Known for their good conductivity and low cost.
• Platinum spark plugs: Offer longer life and better performance.
• Iridium spark plugs: Provide superior performance and longevity.

Maintenance

Spark plugs require regular maintenance and replacement to ensure optimal engine performance. Signs of worn spark plugs include engine misfires, poor fuel economy, and difficulty starting the engine.

Applications

Spark plugs are used in various types of internal combustion engines, including those found in automobiles, motorcycles, lawn mowers, and small engines.

Related Pages

• Ignition system
• Internal combustion engine
• Fuel-air mixture
• Combustion chamber
• Ignition coil
• Magneto
• Piston