Spark plug for petrol engine, has insulating body inserted into screwing body and guiding central electrode, which has borehole that interacts with combustion chamber, and fiber optic pressure sensor that is inserted into borehole

摘要

The plug has a screwing body that is screwed into a wall of a combustion chamber, and that supports a mass electrode (12). A ceramic insulating body (14) is inserted into the screwing body and guides a central electrode (16). The central electrode has a borehole (18) that interacts with the combustion chamber. A fiber optic tube-shaped pressure sensor (22) is inserted into the borehole. A part of the bore hole adjacent to the front end of the electrode is provided with a labyrinth channel or is filled with a temperature resistant porous material.