Spark plug for IC engine

摘要

A spark-plug for an IC engine has a cylindrical metal tube containing a rod-like central electrode inside an insulator. The metal tube has at least two earth electrodes bent towards the central electrode to form separate spark paths. The first earth electrode has its end bent so that the outer surface lies flush with the upper edge of the insulator. The bent end of the second earth electrode lies opposite the central electrode surface. The distance from the earth electrode to the central electrode approximately corresponds to the spark path, the sparks gliding over the insulator surface and jumping across to the earthed electrode at the spot with the shortest distance.