GAS SENSOR

摘要

A gas sensor device is equipped with a pump cell and a sensor cell. The pump cell works to regulate the concentration of oxygen in a measurement gas space. The sensor cell works to measure an oxygen ion current flowing between a sensor electrode and a reference electrode. The gas sensor device is designed to subtract the oxygen ion current value I2, as measured by the sensor cell a given period of time after spraying of fuel into the internal combustion engine is interrupted, from the oxygen ion current value I1, as measured by the sensor cell when the fuel is being sprayed into the internal combustion engine, to derive the concentration of a given gas component based on the corrected oxygen ion current value I. This results in improved accuracy in determining the concentration of the given gas component.

主权项

1. A given gas concentration measuring method of measuring a concentration of a given gas component in exhaust gas flowing in an exhaust pipe of an internal combustion engine using a gas sensor device which is arranged in the exhaust pipe of the internal combustion engine, the gas sensor device comprising:
a solid electrolyte body which has oxygen ion conductivity; a measurement gas space which is formed on one of surfaces of the solid electrolyte body and into which the exhaust gas is introduced as a measurement gas through a diffusion resistor; a reference gas space which is formed on the other surface of the solid electrolyte body and into which a reference gas is introduced; a pump cell which has a pump electrode disposed on a surface of the solid electrolyte body which faces the measurement gas space, the pump cell being designed so that voltage is applied between the pump electrode and a reference electrode disposed on a surface of the solid electrolyte body which faces the reference gas space to regulate a concentration of oxygen in the measurement gas space; and a sensor cell which has a sensor electrode disposed on the surface of the solid electrolyte body which faces the measurement gas space downstream of the pump electrode in a flow direction of the measurement gas, the sensor cell working to measure an oxygen ion current flowing between the sensor electrode and the reference electrode, wherein an oxygen ion current value, as measured by the sensor cell a given period of time after spraying of fuel into the internal combustion engine is interrupted, is subtracted from an oxygen ion current value, as measured by the sensor cell when the fuel is being sprayed into the internal combustion engine to derive the concentration of the given gas component.