Patent ID: 11921078
Assignee: NGK INSULATORS, LTD.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 3:
4. The sensor element according to claim 1,
wherein the surface of the element body includes the face on which the gas inlet opens and one or more adjacent faces that each meet the face along a side of the face,
wherein the protective layer includes an adjacent-face protective layer that covers at least a part of the one or more adjacent faces, and
wherein the adjacent-face protective layer has an internal space formed therein, the internal space being directly communicated with the internal space of the inlet protective layer, an arithmetic average roughness Ras of an inner peripheral surface of the internal space of the adjacent-face protective layer satisfying at least one of conditions below: the arithmetic average roughness Ras is 8 μm or more, and the arithmetic average roughness Ras is higher than the arithmetic average roughness Rac.