PROBLEM TO BE SOLVED: To suppress deterioration in gas detection accuracy in a gas sensor having an internal space in which a sensor element is accommodated even when gas to be measured has a specific component of low concentration.SOLUTION: One aspect of the present disclosure is a gas sensor for measuring a concentration of a component contained in gas to be measured, comprising a sensor element and a casing. The sensor element has a square detection surface which is exposed to gas to be measured. The casing has an internal space for accommodating the sensor element. When the internal space is viewed from the direction perpendicular to the detection surface, an existence region of a gas inlet part in the virtual coordinate plane is defined as a first quadrant. Then, a gas outlet part is included in a third quadrant of the virtual coordinate plane. A midpoint between the gas inlet part and the gas outlet part is within the sensing surface. In this gas sensor, when the gas to be measured introduced into the internal space is transferred from the gas inlet part to the gas outlet part, the gas to be measured and the detection surface can be reliably brought into contact with each other, so that the deterioration in the gas detection accuracy can be suppressed.SELECTED DRAWING: Figure 3COPYRIGHT: (C)2020,JPO&INPIT【課題】センサ素子が格納された内部空間を有するガスセンサにおいて、特定成分の濃度が低い被測定ガスが測定対象である場合でもガス検知精度の低下を抑制する。【解決手段】本開示の一態様は、被測定ガスに含まれる成分の濃度を測定するためのガスセンサであって、センサ素子と、ケーシングと、を備える。センサ素子は、被測定ガスに晒される四角形の検知面を有する。ケーシングは、センサ素子を格納する内部空間を有する。検知面に垂直な方向から内部空間を見た場合の仮想座標平面におけるガス入口部の存在領域を第１象限とした場合に、ガス出口部は仮想座標平面の第３象限に含まれる。ガス入口部とガス出口部との中点は検知面に含まれる。このガスセンサは、内部空間に導入された被測定ガスがガス入口部からガス出口部にかけて移動する際に、被測定ガスと検知面とを確実に接触させることができるため、ガス検知精度の低下を抑制できる。【選択図】 図３
