Spark plug for vehicle hydrogen engine, has cylindrical central electrode projecting over earth electrode in axial direction, and air duct formed between earth and central electrodes

摘要

The plug has a cylindrical central electrode (2) arranged in a central insulator (4), and a flange-shaped earth electrode (3). The central electrode projects over the earth electrode in an axial direction. An air duct (5) is formed between the earth electrode and the central electrode. The insulator forms a socket with large diameter than the central electrode. Tip of the central electrode is flattened.