Masayoshi Matsui

Gas Engine Ignition System for Long-Life Spark Plugs

In high-swirl engines, such as gas engine, multi-spark discharge causes uneven wear of spark plugs because intense swirl breaks the spark discharge path. The ignition system with variable discharge energy solved this problem. Although the reduced discharge energy may weaken the ignitability, the variable discharge energy keeps high ignitability under any engine operating conditions. Gas engines require higher discharge voltage than gasoline engines. The high required voltage has hindered the development of long-life spark plugs. Attaching sub-electrodes strengthened the electric field intensity and succeeded in lowering the required voltage. The combination of the above-mentioned ignition system and spark plug has extended the plug life span.