Exhaust gas sensor seal and protection tube arrangement

摘要

An improved oxygen sensor of the type adapted for installation in the exhaust conduit of an internal combustion engine. The improved sensor uses a metal oxide element to sense the partial pressure of oxygen in the exhaust gases to which the sensor is exposed. The sensor has a steel body and a ceramic member which extends into the exhaust gases to permit the exhaust gases to produce variations in an electrical characteristic of one of the sensor components. The improved sensor has a perforated protection tube that has a radially extending flange. The flange is located between the steel body and the ceramic member, which forms a seal preventing exhaust gases from inside the engine's exhaust conduit from leaking beyond the sensor to the atmosphere.