Gas concentration measuring apparatus designed to establish quick determination of degree of activation of gas sensor

摘要

A gas concentration measuring system for use in air-fuel ratio control of motor vehicle engines is provided which is designed to determine the concentrations of oxygen as a function of an air-fuel ratio of a mixture supplied to the engine through a sensor element. The sensor element is activated by heat produced by an electric heater. The system works to sample the accumulated amount of energy inputted to the sensor element by the heat produced by the heater to determine whether the sensor element has been activated enough to produce an output representing an actual value of the air-fuel ratio correctly or not. Use of the accumulated amount of energy inputted to the sensor element will result in a decreased time required for such a determination as compared with the impedance of the sensor element.