Oxygen Sensor 0258017025

   The working principle of the oxygen sensor on the car: Under certain conditions, the potential difference is generated by using the oxygen concentration difference between the inside and outside of the zirconia, and the greater the concentration difference, the greater the potential difference. The oxygen content in the atmosphere is 21%. The exhaust gas after the combustion of the rich mixture does not actually contain oxygen. The exhaust gas generated after the combustion of the lean mixture or the exhaust gas caused by the lack of fire contains more oxygen, but it is still higher than that in the atmosphere. Much less oxygen. At high temperature and catalyzed by platinum, negatively charged oxygen ions are adsorbed on the inner and outer surfaces of the zirconia sleeve. Since the oxygen in the atmosphere is more than that in the exhaust gas, the side of the casing connected to the atmosphere adsorbs more negative ions than the exhaust gas side, and the concentration difference of the ions on both sides generates electromotive force.

When the oxygen concentration on the exhaust gas side of the automobile casing is low, a high voltage (0.6~1V) is generated between the electrodes of the oxygen sensor. This voltage signal is sent to the automobile ECU for amplification, and the ECU regards the high voltage signal as a rich mixture. , and the low-voltage signal is regarded as a lean mixture. According to the voltage signal of the oxygen sensor, the computer dilutes or enriches the mixture according to the theoretical optimum air-fuel ratio of 14.7:1 as close as possible. Therefore, the oxygen sensor is the key sensor for electronically controlled fuel metering. Only when the oxygen sensor is at high temperature (the end reaches above 300°C), its characteristics can be fully reflected, and the voltage can be output. It responds fastest to changes in the gas mixture at about 800°C, and this characteristic changes considerably at low temperatures.