GAS SENSOR

• Main Authors: OKAMOTO TAKU, IKOMA NOBUKAZU, NAKASONE OSAMU
• Format: Patent
• Language: English; Japanese
• Published: 09.01.2020
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

To improve the accuracy of measuring a specific gas component included in a rich atmosphere gas to be measured.SOLUTION: A gas sensor 100 detects the concentration of a specific gas on the basis of a pump current Ip2 flowing when, for the case where the specific gas is an oxide (e.g., NOx), oxygen generated when the specific gas itself is reduced in a third internal space 61 that is a measurement chamber or, for the case where the specific gas is a non-oxide (e.g., ammonia), oxygen generated when a gas is reduced in the third internal space 61 after the specific gas is converted to an oxide is bailed out from the third internal space 61 so that oxygen in the third internal space 61 becomes a prescribed low concentration. When the gas to be measured is a rich atmosphere, the pump current Ip2 or the specific gas concentration is corrected on the basis of the oxygen concentration of the gas to be measured.SELECTED DRAWING: Figure 1 【課題】リッチ雰囲気の被測定ガスに含まれる特定ガス成分の測定精度を向上させる。【解決手段】ガスセンサ１００は、特定ガスが酸化物（例えばＮＯｘ）の場合には特定ガスそのものを測定室である第３内部空所６１で還元したときに発生する酸素を、特定ガスが非酸化物（例えばアンモニア）の場合には特定ガスを酸化物に変換した後のガスを第３内部空所６１で還元したときに発生する酸素を、第３内部空所６１内の酸素が所定の低濃度になるように第３内部空所６１から外へ汲み出したときに流れるポンプ電流Ｉｐ２に基づいて、特定ガスの濃度を検出する。また、被測定ガスがリッチ雰囲気のときに、ポンプ電流Ｉｐ２又は特定ガス濃度を、被測定ガスの酸素濃度に基づいて補正する。【選択図】図１