| 摘要 |
PURPOSE:To detect a degree of dirt in a flame light detector, by detecting discharge spark light and combustion flame light in a selective manner, while setting a discharge spark at the latter half period of an exhaust stroke down to the reference light. CONSTITUTION:A light signal being detected by a flame light detector 19 is led into a light brancher 22 and branched off in two parts by an optical fiber 21. And, the branched light signal is converted into an electric signal by photoelectric transducers 23 and 24 and lead into an overall control circuit 25. In addition, a crank angle signal out of a crank angle sensor 26 and various parameter signals out of an engine parameter detector 27 are led into the control circuit 25, and on the basis of this determination, spark discharge at a spark plug 20 is carried out by an electronic ignition device 28. Here, each spectral- response characteristic of these photoelectric transducers 23 and 24 is altered. With this constitution, a signal for only combustion flame light and only a signal for discharge spark light at the latter half period of an exhaust stroke are detectable each. And, making the said discharge spark a criterion, compensation takes place for the detected signal of combustion flame light, making it turn to the signal level that corrected a degree of dirt on a detection surface. |
