Gas sensor, gas sensor installation structure, and method for installing gas sensor

摘要

A gas sensor includes a sensor element having a specific function, and a housing containing the sensor element therein and including a thread section, and a sealing surface which forms a sealing section together with an installation section at a position deeper than the thread section in a direction in which the sensor element is inserted. When the housing is screwed into the installation section, the release torque of the housing at 850° C. (1123 K) is 9 N.m or more, and an estimated value of a gap formed between the sealing surface and the installation section at 850° C. (1123 K) that is calculated according to a specific equation is 31 mum or less.