| 摘要 |
PURPOSE:To enable the air-fuel ratio of high accuracy to be detected even in a case that the detection surface of flame light is stained and the transmitted quantity of light is small, by detecting the emission strength of the radical ingredients of the combustion gas of visible radiation range with both light receiving elements, and calculating the air-fuel ratio by these output signal ratios. CONSTITUTION:Combustion flame light introduced from the detection end 3 of the combustion flame light is conducted to an optical fiber cable 4, and is forked therefrom to be conducted to two light catching sensors 5, 6 which are different each other in the emission strength of the CH radical of combustion gas or a spectral sensitivity characteristic. The light receiving elements 5, 6 are connected to a driving process circuit 7 to carry out photoelectric transferring therein, and the signals are conducted to a controller 8 which consists of a microprocessor. In the controller 8, the signals from the driving process circuit 7 are calculated and processed, and the information of an air-fuel ratio is obtained. When the air-fuel ratio is rich, the combustion light is reddish and its wave length is big, and when the air-fuel ratio is lean, the combustion light becomes bluish and its wave length becomes small. Thereby, which wave length ranges of flame become many can be discriminated by taking the ratio of the output signals, so that the judgement of the air-fuel ratio can be obtained. |
