Abstract: A shield assembly for protecting a sensing element of a gas sensor, the shield assembly includes an outer shield comprising an elongated outer wall and an inner shield comprising an inner elongated wall. The elongated outer wall includes a first end, a second end, and a tip portion disposed across the second end of the outer wall. The tip portion includes at least one elongated aperture extending therethrough and the elongated outer wall is configured to not have any openings between the first end and the second end. The inner elongated wall is disposed within the elongated outer wall. The inner elongated wall includes a first open end, a second open end, and a flange portion extending from a periphery of the first open end of the inner elongated wall.

Abstract: This invention provides a solid electrolyte, electrochemical-type oxygen sensing device which is suitable for detecting oxygen partial pressures of exhaust gases emitted from an internal combustion engine. The oxygen sensing device of this invention has a novel self-aligning fixturing means for rigidly securing, sealing, and electrically contacting the solid electrolyte body within the sensor assembly. The electrically conductive fixturing means also electrically communicates the galvanic output signal generated between the reference and measuring electrodes provided on the solid electrolyte body to an external electrical connector. The fixturing means is a substantially tubular body having an outwardly flared region which is contiguous with an inwardly tapered end. The inwardly tapered end is matched to the inner diameter of the open end of the solid electrolyte body.

Abstract: An air-fuel ratio control system for an internal combustion engine supplies a very small sample of the air-fuel mixture being inducted to an air-fuel ratio sensor. A heater heats the sensor and also heats and ignites the air-fuel mixture sample at the sensor. A fuel system control controlled by the sensor then adjusts the air-fuel ratio of the mixture being inducted into the engine to the stoichiometric value.