Sensor control apparatus

An oxygen sensor control apparatus which obtains, when a fuel cut operation is performed so as to stop supply of fuel to an internal combustion engine, a correction coefficient used to calibrate the relation between oxygen concentration and an actual output value of an oxygen sensor attached to an exhaust pipe of the internal combustion engine and which detects the oxygen concentration of exhaust gas flowing through the exhaust pipe by making use of the actual output value and the correction coefficient, the apparatus being characterized by comprising:

• average output value calculation means for excluding, from a plurality of actual output values of the oxygen sensor acquired during a single period of the fuel cut operation or a plurality of concentration corresponding values which represent oxygen concentrations calculated from the actual output values acquired during a single period of the fuel cut operation, those values which fall outside a predetermined first range, and for calculating an average output value by averaging the remaining values;
• inter-fuel-cut average output value calculation means for calculating an inter-fuel-cut average output value by averaging a plurality of average output values calculated for a predetermined number of times of the fuel cut operation;
• and
• correction coefficient calculation means for obtaining a new correction coefficient for correcting the actual output value of the oxygen sensor, on the basis of the inter-fuel-cut average output value and a reference output value set in advance,
• wherein, when the inter-fuel-cut average output value deviates from a predetermined third range a predetermined number of times continuously, the correction coefficient calculation means obtains the correction coefficient by use of at least one of a plurality of the inter-fuel-cut average output values deviating from the third range.