| 摘要 |
PURPOSE:To measure an oxygen partial pressure in a measuring gas from a voltage at an output terminal, by amplifying an electromotive force between electrodes respectively on the reference and measuring gas sides of an oxygen ion conducting solid electrolyte with a differential amplifier. CONSTITUTION:A bag tube-shaped solid electrolyte 2 is mounted on a path 1 where a measuring gas flows. The electrolyte 2 has a measuring gas side electrode 3 and a reference gas side electrode 4 both made of platinum on both sides thereof. The electrode 3 is grounded while the electrode 4 is connected to a positive input terminal 6 of a differential amplifier 5. An output terminal 7 of the amplifier 5 is connected to a microprocessor 10 through an A/D comparator 9. On the other hand, a negative input terminal 8 of the amplifier 5 is connected to the microprocessor 10 through a D/A comparator 11. A voltage at the negative input terminal 8 is adjusted according to temperature near the solid electrolyte to measure an oxygen partial pressure in the measuring gas with the microprocessor 10 from the current voltage at an output terminal 7 of the differential amplifier 5. |
