SIMULATED TEMPERATURE CALCULATION DEVICE OF EXHAUST SYSTEM PART OF INTERNAL COMBUSTION ENGINE AND ELECTRIC HEATER CONTROL DEVICE OF AIR-FUEL RATIO SENSOR FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To obtain the temperature of exhaust system parts of an internal combustion engine, accurately and simply.;SOLUTION: An oxygen sensor 31 is arranged inside an engine exhaust passage, and a water-temperature sensor 28 for detecting the engine cooling-water temperature is installed on an engine body 1. The initial value of a sensor simulated temperature showing the temperature of the oxygen sensor 31 is set corresponding to the engine cooling-water temperature. The temperature is renewed successively corresponding to the engine operation state from the initial value, to calculate the sensor simulated temperature. By this method, if the sensor simulated temperature is lower than a heater operation temperature, an electric heater 41 of the oxygen sensor 31 is operated, and if the sensor simulated temperature is higher than a heater stopping temperature, the electric heater 41 is stopped.;COPYRIGHT: (C)2001,JPO