| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To detect an air-fuel mixture concentration under an operation condition, even in an engine of high rotation type under a high heat load. <P>SOLUTION: When incident optical fibers 35 and emission optical fibers 36 are arranged inside an ignition plug 10, infrared rays emitted from the incident optical fibers 35 are reflected by a mirror 39, the reflected rays are made to get incident into the emission optical fibers 36, and the air-fuel mixture concentration is detected based on intensity of the reflected rays, the number of the emission optical fibers 36 is increased therein more than that of the incident optical fibers 35, and a recovery level of the reflected rays is increase thereby to enhance an S/N ratio. The mirror 39 is made of Si-Cr alloy the same as a plug electrode to enhance heat resistance, and is fixed weldedly to a main body. A ceramic adhesive is used as an adhesive for bundling the optical fibers to be coated, and end faces of the optical fibers are ground together with the adhesive, after cured. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
