Patent ID: 9347913
Filing Date: 2016-05-24
CPC Classification: G01N

Claim Text:
1. A gas sensor control apparatus for controlling a gas sensor for sensing a concentration of a specified gas, the gas sensor including a cell including a solid electrolyte member and a pair of electrodes formed on the solid electrolyte member, the gas sensor control apparatus comprising: an electronic controller comprising: a heater regulating section to control a supply of electricity to a heater included in the gas sensor; a sensor control circuit to sense an impedance of the cell of the gas sensor, from an output of the cell; an impedance condition examining section to examine whether the impedance sensed by the sensor control circuit is greater than or equal to a predetermined abnormality judging threshold; a voltage condition examining section to examine whether a maximum effective voltage is applied to the heater, when the impedance is judged to be greater than or equal to the predetermined abnormality judging threshold; a duration measuring section to examine whether an application time duration of application of the maximum effective voltage to the heater becomes equal to or longer than a predetermined heater overheat preventing time; and a voltage decreasing section to command the heater regulating section to apply, to the heater, a lower effective voltage which is lower than the maximum effective voltage and which is so set as to hold the temperature of the cell higher than or equal to 500° C. when the application time duration becomes equal to or longer than the predetermined heater overheat preventing time.