Patent ID: 8377275
Filing Date: 2013-02-19
Classification: G01N,Y02A

Abstract:
1. A gas sensor control apparatus including a sensor drive circuit which is connected to a gas sensor having at least one cell composed of a solid electrolyte body and a pair of electrodes provided on the solid electrolyte body and which is adapted to supply electricity to the cell in order to drive the gas sensor, the gas sensor control apparatus comprising: a controller programmed to: selectively output a deenergization instruction for setting the sensor drive circuit to a deenergization state for stopping supply of electricity to the cell and an energization instruction for setting the sensor drive circuit to an energization state for supplying electricity to the cell; set the sensor drive circuit to the deenergized state or the energization state in accordance with the selectively output deenergization instruction or energization instruction, respectively; detect a wiring anomaly of the sensor drive circuit or the gas sensor; perform in response to detecting the wiring anomaly, return-from-anomaly checking processing so as to output the deenergization instruction for setting the sensor drive circuit to the deenergization state and then output the energization instruction for setting the sensor drive circuit to the energization state, and perform determination processing so as to determine whether or not the wiring anomaly has disappeared as a result of performance of the return-from-anomaly checking processing; finally determine, on the basis of the result of the determination processing, whether or not the wiring anomaly has occurred; and control a heater provided on the gas sensor so as to heat the cell to an activation temperature or higher, wherein the control comprises energizing the heater at an intermediate voltage which is lower than a maximum voltage, but not lower than a voltage at which the heater can maintain the activation temperature of the cell, during a period between a point in time at which the wiring anomaly is first detected and a point in time at which it is finally determined whether or not the wiring anomaly has occurred.