| 摘要 |
PURPOSE:To always read out output current of a sensor corresponding to predetermined gas concentration by constituting a porous electrode on either one surface of an ion conduction plate of a main electrode and an auxiliary electrode. CONSTITUTION:Assuming that voltage to be applied to an auxiliary electrode 5 is within a limiting current region as well as voltage to be applied to a main electrode 4, current flowing to each electrode is proportional in magnitude to an area of each electrode, making the sum of the current a limiting current value corresponding to predetermined gas concentration. If deterioration of an ion conduction plate 1 of a gas concentration proceeds, output current of the electrode 5 decreases. Since pumping function wherein predetermined gas which has been ionized transfers through the conduction plate is determined by a size of a gas diffusion hole 8 of the sensor in this case, even if the current flowing in the electrode 5 decreases, the sum of current does not change with increase in the current of the electrode 4 by the amount of reduction in the total current flowing in the electrode 5. |
