Ignition

Ignition is a required operation on the combustion stroke of a gasoline engine. The compressed air-fuel mixture drawn into the cylinder is ignited by an spark plug, becomes exhaust gas after combustion (expansion), and is discharged from the cylinder.
This ignition method applies high voltage of several thousand volts or more to a spark plug electrode gap, thus discharging a spark whose spark energy causes the air-fuel mixture sent into the cylinder to ignite and expand.
Ignition systems include magneto ignition method systems that use electromotive force of their own generators as energy sources for generating high voltage ignition electricity, and battery ignition method systems that use battery voltage as ignition energy.
Most small gasoline engines use the magneto ignition method.