Patent ID: 8741118
Filing Date: 2014-06-03
Classification: F02D,G01N

Abstract:
1. A sensor control apparatus comprising: a gas sensor for installation in an exhaust pipe of an internal combustion engine, the gas sensor including an oxygen concentration detection cell comprising a first solid electrolyte body, a reference electrode and a detection electrode, the reference electrode and the detection electrode being formed on the first solid electrolyte body and the oxygen concentration cell generating a voltage between the detection electrode and the reference electrode depending on an oxygen concentration of a measurement target gas; a heater that heats the gas sensor; an electric current supply unit that supplies electric current to the oxygen concentration detection cell so as to pump oxygen from the detection electrode to the reference electrode through the first solid electrolyte body; an activation determination unit that determines whether or not a temperature of the gas sensor is equal to or higher than an activation determination temperature; and a heater control unit programmed to control electric current supplied to the heater by setting a first target temperature equal to or higher than the activation determination temperature as a target temperature of the heater when the activation determination unit determines that the temperature of the gas sensor is equal to or higher than the activation determination temperature, wherein the sensor control apparatus further includes: wherein the heater control unit is programmed to control electric current supplied to the heater by switching a target resistance value to a first target resistance value corresponding to the first target temperature when the activation determination unit determines that the temperature of the gas sensor is equal to or higher than the activation determination temperature, and wherein the first temperature switching unit is programmed to control electric current supplied to the heater by switching the target resistance value to a second target resistance value corresponding to the second target temperature when the automatic stop detection unit detects the automatic stop of the internal combustion engine.