Ngk Spark Plug Company, Limited

Kouji Toida

Ai Igarashi

Shun Sakuma

Hitoshi Furuta

Akinori Kojima

Akihiro Hara

A plate-shaped sensor element () including at least a first layer (), a second layer (), and a third layer () being stacked in a stacking direction. The first layer and the third layer are mainly formed of ceramic. The second layer is disposed between the first layer and the third layer in the stacking direction. The second layer has an air introduction hole () opened at an end surface. In a cross-section perpendicular to a direction of an axis O, a length Lof a shortest line segment Pconnecting an upper end surface () of the sensor element and the centroid Gof the sensor element and a length Lof a shortest line segment Pconnecting the upper end surface of the sensor element and the centroid Gof the air introduction hole, satisfy a relationship of |L&#x2212;L|/L&#x2264;0.05.

Sensor element and gas sensor including the sensor

A method for producing a gas sensor element (), the gas sensor element including a diffusive porous layer () disposed in a measurement chamber () and exposed to the outside and a ceramic insulating layer () forming sidewalls of the measurement chamber. The method includes transferring green diffusive porous layer pieces () cut in advance so as to have prescribed dimensions onto a first ceramic green sheet (); applying an insulating paste which later becomes the ceramic insulating layer to the first ceramic green sheet; laminating the first ceramic green sheet onto a second ceramic green sheet () to form a ceramic laminate (); cutting the ceramic laminate along prescribed cutting lines C to obtain a plurality of gas sensor element pieces; and firing the gas sensor element pieces.

Method for producing gas sensor element

A gas sensor element comprises a solid electrolyte layer; a detection electrode provided on one surface of the solid electrolyte layer; a reference electrode provided on another surface of the solid electrolyte layer; a first layer provided on a side where the other surface of the solid electrolyte layer is present, and having a reference gas flow path; and a heater layer provided on a side opposite to a side where the solid electrolyte layer is provided. In the gas sensor element, an introduction flow path is formed as a flow path for guiding the reference gas from outer surfaces of the gas sensor element to the reference gas flow path. The introduction flow path has an opening provided at an outer surface that is perpendicular to a stacking direction of the gas sensor element and is provided on a side opposite to the heater layer.

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Kani, Japan

Kouji Toida