摘要 |
<p>An optical pressure sensor assembly integrated with a spark plug (16) and spark plug boot (12). The pressure sensor comprises an optical fiber (34) with a pressure diaphragm (36) at the tip to sense pressure and pressure changes within the combustion chamber (32) of a spark ignition engine. A channel (30) is provided in the spark plug to hold the sensor. The diaphragm (36) of the sensor is located closer to the spark electrode than to the electric conductor which is encased by the boot (12). The optical fiber (34) is contained within a shaft that is routed through the boot (12) and into the channel (30). The optical fiber (34) is operatively and electrically connected to the vehicle's engine controller. The opto-electric connection to the vehicle's engine controller is made adjacent a coil (72) in the boot (12) or removed from the coil (72). The fiber (34) is surrounded by a non-metallic shaft (22) outside the engine. Inside the spark plug (16), the shaft is metallic.</p> |