Wide range oxygen sensor

摘要

A wide range oxygen sensor is provided which operates partially in the diffusion limited current mode to provide an output which is proportional to the oxygen partial pressure in a gas mixture which is sensed, such as the exhaust gas of an automotive internal combustion engine. The wide range oxygen sensor is constructed to have a planar structure with a single solid electrolyte layer that is shared by electrochemical storage, pumping and reference cells and which is deposited using known thermal deposition techniques. As a result, the wide range oxygen sensor of the present invention is characterized as being relatively low cost and readily producible under mass production conditions. Moreover, the wide range oxygen sensor is capable of rapidly and accurately sensing the exhaust gas oxygen partial pressure while the engine is operating in either the fuel-rich or fuel-lean condition to enable the evaluation of the air-to-fuel ratio of the precombustion fuel mixture.