| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique for calibrating the output from an oxygen sensor easily and accurately even when the oxygen sensor is directly inserted into a furnace.SOLUTION: An oxygen sensor calibration system comprises: an oxygen sensor 1a that is inserted into the inside of a carburizing furnace 10 in which a process using a gas is performed and has a solid electrolyte that generates an electromotive force according to the difference in oxygen concentration between gases contacting both ends of the solid electrolyte; a gas supply unit 13a that is connected to the oxygen sensor 1a, supplies a reference gas (clean air) having an oxygen concentration level as a calibration standard to one end of the solid electrolyte located in such a manner that the solid electrolyte contacts a furnace-in atmosphere gas of the carburizing furnace 10 directly, and supplies a span adjustment gas having an oxygen concentration level lower than the oxygen concentration level of the reference gas to the other end of the solid electrolyte; and a voltage converter (regulator) 20 that is connected to the oxygen sensor 1a, adds the set correction amount to an electromotive force generated by the contact between the reference gas and the span adjustment gas, and thereby determines a calibration value of the electromotive force.SELECTED DRAWING: Figure 1 |
