| 摘要 |
PURPOSE:To enhance measuring accuracy by compensating the output of a sensor corresponding to the pressure of the gas to be measured at the place exposed to the main body of a sensor. CONSTITUTION:A pair of wide range air/fuel ratio sensors 1, 2 of types sensitive and nonsensitive to nitrogen oxide in gas to be measured are provided. The concn. of the respective gas components in the gas to be measured is converted into O2-concn. by the sensor 1 and the output proportional thereto is issued. The concn. of the gas components from which NO is removed in the same gas to be measured is converted into O2-concn. by the sensor 2 of the type nonsensitive to NO and the output proportional thereto is issued. Subsequently, the outputs of the sensors are compensated corresponding to the pressure of the gas to be measured at the places exposed to the respective sensors by pressure compensation means 4, 5. By this method, the outputs of the sensors to reference pressure are always obtained even when the pressure of the gas to be measured varies. |
