Fiber optic combustion pressure sensors for engine knock and misfire detection

摘要

PCT No. PCT/US96/04637 Sec. 371 Date Mar. 17, 1999 Sec. 102(e) Date Mar. 17, 1999 PCT Filed Apr. 3, 1996 PCT Pub. No. WO97/31251 PCT Pub. Date Aug. 28, 1997Spark 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.