FIBER OPTIC COMBUSTION PRESSURE SENSORS FOR ENGINE KNOCK AND MISFIRE DETECTION

摘要

Spark plug (20) integrated fiber optic combustion pressure sensors (30, 36) are configured to decrease heat and fatigue damage to the critical diaphragm (40) and fiber tip (37). A cup-shaped diaphragm (40) having non-uniform thickness reduces stress on the diaphragm and increases the reliability of the sensor. The effects of overpressure on the sensor are reduced by providing an angled portion (42) on the ferrule.